172RMM15 172 SERIES (1996 & ON) Cessna_172R_1996on_MM_C172RMM Cessna 172R 1996on MM C172RMM

User Manual: Cessna_172R_1996on_MM_C172RMM

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Maintenance Manual

172

MOE

196 & ON~~~

OV

Member of GAMA

COPYRIGHT © 1996
CESSNA AIRCRAFT COMPANY
WICHITA, KANSAS, USA
172RMM15

2 DECEMBER 1996
172RMM15
~~REVISION

15

1JUY20
1 JULY 2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
PAGE

CHAPTER-SECTION-SUBJECT

DATE

00-Title
00-List of Effective Pages
00-Record of Revisions
00-Record of Temporary Revisions
00-Table of Contents
LIST OF MANUFACTURERS' TECHNICAL
PUBLICATIONS

Pages 1-6

Jul 3/2006

SERVICE BULLETIN LIST

Pages 1-6

INTRODUCTION
LIST OF REVISIONS

Pages 1-6

Jul 1/2007
Jun 7/2004

Page 1

Jul 1/2007

LIST OF CHAPTERS

Page 1

Jul 1/2007

00
©Cessna Aircraft Company

-

LIST OF EFFECTIVE PAGES

Page 1 of 1
Jul 1/2007

Revision
Number

Date
Inserted

Date
Removed

Page
Number

Revision
Number

Date
Inserted

Date
Removed

Page
Number

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS..............Page
List of Manufacturers' Technical Publications ..................
SERVICE BULLETIN LIST .............................
Service Bulletins ...............................
INTRODUCTION .................................
General ...................................
Cross-Reference Listing of Popular Name Versus Model Numbers and Serials ..
Coverage and Format...............
Temporary Revisions .............................
Serialization .................................
Material Presentation .............................
Service Bulletins ...............................
Using the Maintenance Manual.........................Page
Effectivity Pages
Revision Filing Instructions...........................Page
Identifying Revised Material ..........................
Warnings, Cautions and Notes.........................Page
Propeller Aircraft Customer Care Supplies and Publications Catalog . ......
Customer Comments on Manual........................Page
LIST OF REVISIONS................................Page
Revisions ..................................
LIST OF CHAPTERS................................Page

Page 1
Page 1
Page 1
Page
Page
Page
Page

2
2
2
2
3
5
5
Page 6
6
Page 6
6
1
Page 1
1

00 -CONTENTS
© Cessna Aircraft Company

1
Page 1
Page 1
Page 1

Pagel1of 1
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
1.

List of Manufacturers' Technical Publications
A.

Outlined below is a list of manufacturers' publications.

CHAPTER 22 - AUTOFLIGHT
Item

Cessna Part
Number

Autopilot

ManufacturersO Part Number

Publication Part
Number

Publication
Title

Manufacturer

KAP140

006-00991-0002

KAP 140
Installation
Manual

Allied Signal
101 N. Industrial
Pkwy
New Century,
KS 66031

Manufacturers'
Part Number

Publication Part
Number

Publication
Title

Manufacturer

KX155A

006-10542-0000

Nav/Com
Installation
Manual

Allied Signal

G1000 Line
Maintenance
Manual

Garmin USA
1200 East 151st
Street
Olathe, KS
66062

CHAPTER 23 - COMMUNICATIONS
Item
Nav-Com

Cessna Part
Number

GIA 63
Integrated
Avionics
Unit

LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
CHAPTER 24 - ELECTRICAL POWER
Item

Cessna Part
Number

Manufacturers
Part Number

Publication Part
Number

Publication
Title

Manufacturer

24 Volt
Battery
Charger

TSC-01V

Teledyne
Battery Products
TSC-01V 24 Volt
Battery Charger

Teledyne
Continental
Motors Battery
Products
840
W.
Brockton
Avenue
Redlands, CA
92374
Phone: 1-800456-0070

Standby
Battery

AVT-200413

Cyclon Selection
Guide (Third
Edition) (NOTE

AVT Inc.

1)

DBA Electritek -

AVT
400
East
Mineral Avenue
Littleton, CO
80122-2604
Hawker
617
North
Ridgeview Drive
Warrensburg,
MO 64093-9301

NOTE 1: The power cells inside the Standby Battery are manufactured by Hawker and the manufacturer
publication that is shown above is from Hawker. AVT is the supplier of-the Standby Battery pack that
is installed in the airplane. The data shown in the Hawker manual is informational only. Maintenance
procedures for the Standby Battery given in Chapter 24, Standby Battery - Maintenance Practices
must be followed.
CHAPTER 25 - EQUIPMENT FURNISHING

Item
Air Bag
Assembly

Cessna Part
Number

Manufacturers
Part Number

Publication Part
Number

Publication
Title

Manufacturer

7035-1-011-

E508804

Supplemental
Maintenance
Manual

AmSafe
Aviation
E.
5456
McDowell Rd.
Mesa,
AZ 85215
www.amsafe.com

8105 (Co-Pilot's
Seat)
7035-1-0218105 (Pilot's
Seat)
7035-2-0118105 (LH Rear
Seat)
7035-2-0218105 (RH Rear
Seat)

LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
© Cessna Aircraft Company

Page 2
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
CHAPTER 25 - EQUIPMENT FURNISHING
Item

Cessna Part
Number

Inflation
Assembly

Manufacturers
Part Number

Publication Part
Number

Publication
Title

Manufacturer

508792-401
(Co-Pilot's
Seat)

E508804

Supplemental
Maintenance
Manual

AmSafe
Aviation

508794-401
(Pilot's Seat)
Electronics Module
Assembly

508358-409

E508804

Supplemental
Maintenance
Manual

AmSafe
Aviation

ThreePoint Air
Bag Belt

70352030118105
(Co-Pilot's
Seat)

E508804

Supplemental
Maintenance
Manual

AmSafe
Aviation

E508804

Supplemental
Maintenance
Manual

AmSafe
Aviation

Publication Part
Number

Publication
Title

Manufacturer

Component
Maintenance
Manual

Cleveland
Wheels
and
Brakes/Parker
Aerospace
Parker Hannifin
Corporation
1160
Center
Road
Avon, OH 44011

70352040218105
(Pilot's Seat)
70352050218105
(LH Rear Seat)
70352060218105
(RH Rear Seat)
V23
System
Diagnostic
Tool

508668-201

CHAPTER 32 - LANDING GEAR
Item
Cleveland
Wheels
and
Brakes

Cessna Part
Number

Manufacturers
Part Number
None

LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
O Cessna Aircraft Company

Page 3
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CHAPTER 34 - NAVIGATION
Manufacturers
Part Number

Publication Part
Number

Publication
Title

Manufacturer

Blind
Encoder

SSD120-20

M881000D

Altitude Encoder/
Digitizer Owner/
Installation
Manual

Trans-Cal
Industries, Inc.
16141
Cohasset St.
Van Nuys, CA
91406

Automatic
Direction
Finder

KR87

006-00184-0005

Installation
Manual

Allied Signal

Global Positioning
System

KLN89/89B

006-10522-0001

Installation
Manual

Allied Signal

Autopilot

KAP 140

006-00991-0000

Installation
Manual

Allied Signal

Nav
Indicators

K1208/209

006-0140-0003

Installation
Manual

Allied Signal

Nav
Indicators

K1209A

006-10543-0000

Installation
Manual

Allied Signal

GDC 74
Air Data
Unit

G1000 Line
Maintenance
Manual

Garmin USA
1200 East 151st
Street
Olathe, KS
66062

GIA 63

G1000 Line
Maintenance
Manual

Garmin USA

G1000 Line
Maintenance
Manual

Garmin USA

G1000 Line
Maintenance
Manual

Garmin USA

G1000 Line
Maintenance
Manual

Garmin USA

G1000 Line
Maintenance
Manual

Garmin USA

Item

Cessna Part
Number

Integrated
Avionics
Unit

GMU 44
Magnetometer
GRS 77

AHRS
GTX 33
Transponder

GDU 1040
(PFD/
MFD)

LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
C Cessna Aircraft Company

Page 4
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CHAPTER 71 - POWERPLANT
Manufacturers
Part Number

Publication Part
Number

Publication
Title

Manufacturer

Engine

10360-L2A

60297-12

Operator's
Manual
Textron
Lycoming Aircraft
Engines

Textron
Lycoming
652
Oliver Street
Williamsport,
PA 17701

Engine

10360-L2A

PC-306-12

Parts Catalog

Textron
Lycoming

Engine

10360-L2A

60294-7

Direct Drive
Engine Overhaul
Manual

Textron
Lycoming

Item

Cessna Part
Number

CHAPTER 73 - ENGINE FUEL AND CONTROL
Item

Cessna Part
Number

Manufacturers
Part Number

Publication Part
Number

Publication
Title

Manufacturer

Fuel
Injection
System

RSA-5

15-338D

RSA-5 & RSA10 Fuel Injection
Systems
Operation &
Service Manual

Precision
Airmotive
3220 100th St
S.W.#E
Everett, WA
98204

Fuel
Injection
System

RSA-5

15-810B

Troubleshooting
Techniques for
the Precision
Airmotive RSA
Fuel Metering
System

Precision
Airmotive

CHAPTER 74 - IGNITION
Item

Magneto

Cessna
Part
Number

Manufacturers Part
Number

Publication Part
Number

Publication Title

Manufacturer

6351/6361

L-1363C

4300/6300
Series Magneto
Maintenance and
Overhaul Manual

Slick
Aircraft
Products
530 Blackhawk Park
Ave.
Rockford, IL 61104

LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
© Cessna Aircraft Company

Page 5
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CHAPTER 77 - ENGINE INDICATING
Item

Cessna Part
Number

Manufacturers
Part Number

Publication Part
Number

GEA 71
Engine/
Airframe
Unit

Publication
Title

Manufacturer

G1000 Line
Maintenance
Manual

Garmin USA
1200 East 151st
Street
Olathe, KS
66062

Publication
Title

Manufacturer

G1000 Line
Maintenance
Manual

Garmin USA
1200 East 151 st
Street
Olathe, KS
66062

CHAPTER 79 - OIL
Item

Cessna Part
Number

Manufacturers
Part Number

Publication Part
Number

GDU 1040

LIST OF MANUFACTURERS' TECHNICAL PUBLICATIONS
© Cessna Aircraft Company

Page 6
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
SERVICE BULLETIN LIST

1.

Service Bulletins

Service
Bulletin
Number

Title

Service
Bulletin Date

Manual
Incorporation

SB97-1 1-01

Pilot's Operating Handbook and Checklist Revision

May 12/97

May 3/99

SB97-1 1-04

Aft Baggage Placard Inspection/Replacement

Nov 3/97

May 3/99

SB97-1 1-05

Altimeter Certification Logbook Entry Verification

Dec 15/97

May 3/99

SB97-22-01

Bendix/King Autopilot Flight Computer Modification

Oct 6/97

May 3/99

SB97-24-01

Electrical Wire Bundle Inspection

Dec 15/97

May 3/99

SB97-25-01

Aft Bench Seat Back Modification

Aug 11/97

May 3/99

SB97-26-01

Fire Extinguisher Mounting Bracket Inspection

Dec 22/97

May 3/99

SB97-27-01
Rl

Inspection of Elevator and Elevator Trim Control
Cable Pulleys

Dec 14/98

May 3/99

SB97-28-01

Inspection of Fuel Strainer Drain and Engine Muffler
Tailpipe

Jun 6/97

May 3/99

SB97-33-01
Rl

Light Dimming Module Resistor Installation Inspection

Dec 14/98

May 3/99

SB97-34-01

KLN 89B GPS Navigation System Approach
Restrictions

Jul 2/97

May 3/99

SB97-34-02
Rl

Alternate Static Source Valve Inspection

Dec 6/97

May 3/99

SB97-53-01

Inspection of Fuselage Station 205.812 Tailcone
Bulkhead

Jul 1/97

May 3/99

SB97-53-02
Rl
SB97 71 -01
Rl

Lower Forward Doorpost Fastener Installation

Sep 15/97

May 3/99

Alternate Air Door Hinge Assembly Replacement

Jul 27/98

May 3/99

SB97-71 -02

Engine Induction Drain Line Inspection

Dec 22/97

May 3/99

SB98-1 1-01

Voltage Polarity Placard Installation

Mar 23/98

May 3/99

SB98-1 1-02

Pilot's Operating Handbook and Checklist Revisions

Mar 30/97

May 3/99

SB98-1 1-05

German Pilot's Operating Handbook and Checklist
Revisions

Sep 21/98

May 3/99

SB98-1 1-06

Brazilian Pilot's Operating Handbook Revision

Oct 12/98

May 3/99

SB98-20-01
Rl

Firewall Sealant Replacement

Dec 31/98

May 3/99

SB98-24-01

Alternator Replacement

Mar 30/98

Jan 15/01

SB98-25-01

Pilot and Copilot Seat Back Pivot Fitting Inspection

Jun 1/98

May 3/99

SB98-25-02

Pilot and Copilot Seat Roller Inspection

Sep 14/98

May 3/99

SB98-27-01

Flap Follow Up System Cable Clamp Inspection

Mar 30/98

May 3/99

SERVICE BULLETIN LIST
©Cessna Aircraft Company

Pagel1
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
Service
Bulletin Date

Manual
Incorporation

Aileron Control Cable Routing Inspection

Dec 31/98

May 3/99

SB98-27-03

Aileron Primary Control Cable-to-Drum Lock Clamp
Inspection

Jun 1/98

May 3/99

SB98-27-05
R2

Right Wing Aileron Control Cable Routing Inspection

Dec 31/98

May 3/99

SB98-27-06

Flight Control Cables and Travel Inspection

Jun 15/98

May 3/99

SB98-27-07

Control Yoke Attach Bushing Installation

Sep 21/98

May 3/99

SB98-28-01

Engine Fuel Pressure Transducer Inspection and
Replacement

Mar 2/98

May 3/99

SB98-28-02
R1

Wing to Fuselage Fuel Hose Clamp Inspection

Feb 1/99

Aug 1/00

SB98-28-03

Fuel Shutoff Valve Cable Clamp Inspection

May 4/98

May 3/99

SB98-34-01
R1

KLN 89B GPS Navigation System IFR Non-Precision
Approach Limitation

Aug 3/98

May 3/99

SB98-37-01
R1

Airborne Vacuum Pump Inspection

Nov 2/98

Aug 1/00

SB98-52-01

Baggage Door Seal Replacement

Feb 23/98

May 3/99

SB98-53-01
R1

Firewall Rivet Inspection

Dec 14/98

May 3/99

SB98-53-02
R2

Firewall Inspection and Cowl Mount Alignment

Dec 26/00

Aug 18/01

SB98-55-01

Elevator Stop Bolt Bracket Nutplate and Horizontal
Stabilizer Installation Inspection

Jul 6/98

May 3/99

SB98-55-02

Horizontal Stabilizer Inboard Skin Rivet Inspection

Jul 27/98

May 3/99

SB98-57-01

Wing Strut Attach Bolts Nut Torque Inspection

Jun 1/98

May 3/99

SB98-71 -01

Forward Engine Baffle and Heat Shroud Modification

Jul 27/98

May 3/99

SB98-71 -02

Engine Air Filter Replacement

Jul 27/98

May 3/99

SB98-78-01

Engine Exhaust Muffler Inspection and Replacement

Jan 10/98

May 3/99

SB99-1 1-01

Pilot's Operating Handbook Revision

Sep 27/99

Jan 15/01

SB99-21 -01

Fresh Air Vent Replacement

Mar 15/99

Jan 15/01

SB99-24-01

Electrical Power System Modification

Mar 15/99

Aug 1/00

SB99-24-02

Circuit Panel Assembly Cover Installation

Dec 27/99

Aug 1/00

SB99-25-01
R1

Emergency Locator Transmitter (ELT) Operational
Test

Dec 27/99

Jan 15/01

SB99-27-01

Control Yoke Pivot Bolt Inspection/Replacement

Jul 12/99

Aug 1/00

SB99-28-01

Wing Fuel Tank Vent Check Valve Inspection

Apr 26/99

Aug 1/00

SB99-34-01
R1

KLN 89B GPS Navigation System Modification

Apr 24/00

Jan 15/01

Service
Bulletin
Number

Title

SB98-27-02
R1

SERVICE BULLETIN LIST
©Cessna Aircraft Company

Page 2
Jul 1/2007

0

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

Service
Bulletin
Number

Title

Service
Bulletin Date

Manual
Incorporation

SB99-37-01

Vacuum Hose Modification

Dec 27/99

Aug 1/00

SB99-53-03

Elevator Control Yoke Roller Engagement
Inspection/Modification

Dec 6/99

Aug 1/00

SB99-55-01

Vertical Fin Aft Spar Inspection

Mar 29/99

May 3/99

SB99-71 -01
R2

Engine Piston Pin Plug Wear Inspection

Jul 12/99

Aug 1/00

SB99-71 -02

Engine Oil Filler Tube to Engine Mount Clearance

Aug 12/99

Aug 1/00

SB99-71 -05

Engine Valve Seat Inspection

Oct 25/99

Aug 1/00

SB99-73-01

Engine Fuel Manifold Spring Replacement

Jan 8/99

Aug 1/00

SB99-73-02

Engine Fuel Injector Unit Inspection

Feb 1/99

Aug 1/00

SB00-1 1-01

German Pilot's Operating Handbook Revision

Mar 13/00

Aug 1/00

5800-1 1-03

Pilot's Operating Handbook and Pilot's Checklist
Revisions
Pilot's Operating Handbook and Pilot's Checklist
Revisions
KAP-1 40 Autopilot Servo Inspection/Modification

May 22/00

Jan 15/01

Aug 14/00

No Effect

Feb 14/00

Aug 1/00

SBOO-24-01

Main Power Junction Box Circuit Breaker Retrofit Kit
Installation

Mar 13/00

Aug 1/00

SBOO-24-02

Electrical Panel Wiring Modifications

Jun 5/00

Jan 15/01

SBOO-34-01

Pitot Tube Heater Assembly Insulation Installation

Apr 10/00

Jan 15/01

SBOO-37-01

Vacuum System Air Filter Element Inspection!
Replacement

Aug 14/00

Jan 15/01

SBOO-55-01

Rudder Attach Bolt Torque Inspection

Apr 10/00

Jan 15/01

SBOO-57-01
R1

Flap Track and Wing Inboard Trailing Edge Inspection

Apr 28/03

No Eff ect

SBOO-61 -02

Propeller Hub Inspection
Engine Fuel Injection Lines and Support Clamps
Inspection

Aug 14/00

Jan 15/01

Dec 24/01

No Effect

Engine Low Oil Pressure Switch Replacement

Feb 21/00

Jan 15/01

SBOO-34-01

Pitot Tube Heater Insulation Installation

Apr 10/00

Feb 15/02

5801 -11-01

Pilot's Operating Handbook Revisions

Feb 5/01

No Eff ect

SBO1 -11-02

Mar 5/01

No Eff ect

Feb 19/01

No Eff ect

SBO1l-28-03

Pilot's Operating Handbook and Pilot's Checklist
Revisions
Elevator Trim Tab Control Cable Stop Block
Inspection
Fuel Shutoff Valve Control Cable Inspection

Jul 23/01

Feb 15/02

SBO1l-71-01

Engine Fuel Flow Divider Installation Modification

Jan 22/01

No Eff ect

SB00-11-04
SBOO-22-01

SBOO-73-01
R2
SBOO-79-01
Ril

SBO1 -27-01
R1

SERVICE BULLETIN LIST Page 3
©Cessna Aircraft Company

Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
Service
Bulletin Date

Manual
Incorporation

Ignition Switch Center Ground Terminal Inspection

Jun 25/01

No Effect

S1BO1 -53-01

Battery Box Support Inspection Modification

Feb 05/01

Apr 7/03

SB01l-55-0 1

Apr 2/01

No Effect

SBOl-71-02

Elevator Balance Weight Attach Screw
Inspection/Installation
Engine Crankshaft Inspection

Apr 2/01

No Eff ect

SBO01 -27-02

Control Yoke Assembly Inspection

May 28/01

No Effect

SBO1 -28-02

Fuel Selector Shaft Assembly Inspection/
Replacement

May 28/01

Apr 7/03

SBO1 -73-01
R2

Engine Driven Fuel Pump Inspection

Oct 17/05

No Eff ect

SB02-22-01

Honeywell KAP 140 Autopilot System Modification

Nov 25/02

No Effect

SB02-52-01

Cabin Door Handle Replacement

Jan 21/002

No Eff ect

SB02-37-02

Dry Vacuum Pump and Coupling Replacement
Requirements

Feb 18/02

No Eff ect

SB02-37-03

Vacuum System Reducer Fitting

Feb 18/02

Apr 7/03

SB02-25-01

Pilot and Copilot Shoulder Harness Removal

Apr 28/02

Apr 7/03

SB02-37-04

Airborne Air and Fuel Products Check Valve Manifold
Inspection

Oct 28/02

Apr 7/03

SB02-53-02

Firewall Sealant Installation

Dec 16/02

No Effect

SB02-61 -01

Propeller Spinner and Bulkhead Inspection

Jan 21/02

Feb 15/02

SB02-61 -02

Propeller Blade Inspection

Dec 16/02

No Effect

SB03-1 1-02

Pilot's Operating Handbook and Pilot's Checklist
Revisions

Apr 14/03

No Effect

SB03-1 1-04

Pilot's Operating Handbook and Pilot's Checklist
Revision

Oct 27/03

No Effect

SB03-23-01

Honeywell KMA 26 Audio Panel Modification

Jul 28/03

No Eff ect

SB03-24-01

Alternator Replacement

Jul 28/03

No Eff ect

S B03-24-02

MC01-3A Main Electrical Power Junction Box
Modification

Oct 13/03

No Eff ect

SB03-25-01

Armrest Shield Installation

Feb 3/03

No Eff ect

SB03-27-02

Flap Control Bracket Attach Bolts Replacement

Dec 22/03

No Eff ect

SB03-28-01

Fuel Cap Lanyard Removal

Oct 27/03

Jan 2/06

SB03-32-01

Nose Landing Gear Wheel Fairing Modification

Sep 29/03

No Effect

SB03-34-01

Honeywell KS270C, KS271 C, and KS272C Servo
Friction Inspection

Oct 27/03

No Eff ect

SB03-34-02
R1

Altimeter Inspection

Feb 16/04

No Effect

SB03-37-01

Vacuum Manifold Inspection/Replacement

Nov 10/03

Apr 7/03

Service
Bulletin
Number

Title

SB01l-74-0 1

SERVICE BULLETIN LIST
©Cessna Aircraft Company

Page 4
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
Service
Bulletin
Number

Title

SB03-71 -01

Engine Fuel Supply System Modification

May 26/03

SB03-71 -02

Fuel Injection Servo Inspection

May 26/03

No Eff ect

SB03-73-01

Throttle Arm Retention Inspection

Nov .4/03

No Eff ect

SB04-1 1-02

Pilot's Operating Handbook Revision

Aug 30/04

No Eff ect

SB04-24-01

Alternator Control Unit Inspection/Replacement

Mar 1/04

No Eff ect

SB04-25-01
R4
SB04-25-02
R1

Crew Seat Recline Modification

Dec 26/06

No Eff ect

Crew Seat Back Cylinder Lock Inspection and Crank
Arm Modification

Oct 17/05

No Effect

SB04-25-03

Passenger Bench Seat Bolt Installation

Jul 19/04

No Effect

SB04-25-04

Crew Seat Back Cylinder Lock Control
Inspection/Adjustment

Oct 11/04

No Eff ect

SB04-27-02
R1

Elevator Trim Tab Control Cable Inspection

Oct 11/04

No Eff ect

SB04-28-01
R1

Fuel Hose Inspection

Mar 15/04

No Eff ect

SB04-28-03

Engine Fuel Return System Installation

Aug 30/04

No Eff ect

SB04-32-01

Landing Gear Shock Strut Metering Pin Replacement
Nose

Feb 2/04

No Eff ect

SB04-52-01
SB04-55-01
R1

Security Lock Installation

Jun 28/04

No Eff ect

Horizontal Stabilizer Attach Bolt Holes Inspection

Jun 20/05

No Eff ect

SB04-71 -02

Nov 8/04

No Eff ect

SB04-73-01

Engine Starter Inspection/Replacement
Engine Fuel Injection Lines and Support Clamps
Inspection

Aug 30/04

Jan 2/06

SB04-73-02

Engine Fuel Manifold Spring Replacement

Oct 11/04

No Eff ect

SB05-1 1-02

Pilot's Operating Handbook Revisions

Jul 29/05

No Eff ect

SB05-1 1-03

Pilot's Operating Handbook Temporary Revision 2

Aug 29/05

No Eff ect

SB05-22-01

Trim Servo Cable Chain Inspection

Dec 5/05

No Eff ect

SB05-24-01

Jan 31/05

No Effect

SB05-25-01

MC01 -3A Main Electrical Power Junction Box Circuit
Breakers Inspection
Inflatable Seat Belt Restraint Installation Inspection

Mar 7/05

No Eff ect

SB05-25-02

Inflatable Seat Restraints Installation

Apr 25/05

No Effect

SB05-28-01

Fuel Strainer Gasket Inspection

Jan 17/05

No Effect

SB05-33-01

High Intensity Discharge (HID) Landing and Taxi Light
Installation

May 9/05

Jul 1/05

SB05-34-07

Garmin G1000 Obstacle and Terrain Avoidance
System Database Update

Sep 26/05

No Eff ect

Service
Bulletin Date

Manual
Incorporation

SERVICE BULLETIN LIST
©Cessna Aircraft Company

Page 5
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Service
Bulletin
Number

Title

Service
Bulletin Date

Manual
Incorporation

SB05-34-08

Garmin G1000 System Software Upgrade

Sep 26/2005

No Effect

SB05-34-09

Sep 26/05

No Eff ect

Nov 21/05

No Eff ect

Dec 5/05

No Eff ect

SB05-37-01

Garmin G1 000 GDL-69A Weather And Digital Audio
Entertainment Interface Installation
Garmin Gia 63 Integrated Avionics Unit Outside
Cover Replacement
Garmin G1 000 Display Unit (GDU) 1040 Cover Glass
Delamination
Vacuum Pump Inspection/Replacement

Nov 7/05

No Eff ect

SB05-53-03

Floorboard Bulkhead Rivet Inspection

Dec 19/05

No Eff ect

SBOS-57-01

Wing Trailing Edge Rib Inspection

Oct 10/05

No Effect

SB05-73-01

Engine Driven Fuel Pump Inspection

Mar 7/05

No Eff ect

SB06-111-01

Pilot's Operating Handbook Revisions

Mar 27/06

No Eff ect

SB06-11-02

Pilot's Operating Handbook Revisions

Nov 6/06

No Effect

SB06-1 1-03

Pilot's Operating Handbook and Pilot's Checklist
Revisions

Dec 18/06

No Eff ect

SB06-22-01

Honeywell KS270C Pitch Servo and KS271C Roll
Servo Tach Generator Modification

Apr 24/06

No Effect

SB06-24-01

Electrical Ground Strap Inspection

May 8/06

No Eff ect

S B06-24 -02
R1

60 Ampere Alternator Rotor Replacement

Dec 26/06

No Eff ect

SB06-24-03

60 Ampere Alternator Brush Replacement

Dec 18/06

No Eff ect

S B06-24 -04

Circuit Breaker Inspection

Dec 26/06

No Eff ect

SB06-24-05

Circuit Breaker Panel Assembly Inspection

Dec 26/06

No Eff ect

SB06-27-01

Flap Aft Roller Bearing Installation Modification

Apr 10/06

No Eff ect

SB06-32-01

Brake Master Cylinder Covers Inspection

Sep 25/06

No Eff ect

SB06-34-01

Honeywell KT 73 MODE S Transponder Installation

Feb 27/06

No Eff ect

SB06-34-02
R1
SB06-34-03

Garmin G1000 System Software Upgrade

Nov 6/06

No Eff ect

Enablemnent of Garmin G 1000 Terrain Awareness
Warning System CLASS-B3 (TAWS-B)

May 22/06

No Eff ect

SB06-34-04

Automatic Direction Finder (ADF) and Distance
Measuring Equipment (DME) Installation

Oct 23/06

No Eff ect

SB06-52-01

Cabin Door Modification

Mar 27/06

No Eff ect

SB06-57-01

Upper Wing Skin Modification

Nov 6/06

No Effect

SB06-71 -02

Engine Compartment Fuel Hoses Security Inspection

Jun 19/06

No Effect

SB05-34-1 1
SB05-34-1 2

SERVICE BULLETIN LIST
C Cessna Aircraft Company

Page 6
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
INTRODUCTION
1.

General

WARNING: All Inspection Intervals, replacement time limits, overhaul time
limits, the method of Inspection, life limits, cycle limits, etc.,
recommended by Cessna are solely based on the use of new,
remanufactured, or overhauled Cessna approved parts.
If parts
are designed, manufactured, remanufactured, overhauled, and/or
approved by entitles other than Cessna, then the data In Cessna's

maintenance/service manuals and parts catalogs are no longer
applicable and the purchaser Is warned not to rely on such data
for non-Cessna parts. All Inspection Intervals, replacement time
limits, overhaul time limits, the method of Inspection, life limits, cycle
limits, etc., for such non-Cessna parts must be obtained from the
manufacturer and/or seller of such non-Cessna parts.
A.

The information in this publication is based on data available at the time of publication and is updated,
supplemented, and automatically amended by all information issued in Service Newsletters, Service
Bulletins, Supplier Service Notices, Publication Changes, Revisions, Reissues and Temporary
Revisions. All such amendments become part of and are specifically incorporated within this
publication. Users are urged to keep abreast of the latest amendments to this publication through
information available at Cessna Authorized Service Stations or through the Cessna Propeller Aircraft
Product Support subscription services. Cessna Service Stations have also been supplied with a
group of supplier publications which provide disassembly, overhaul, and parts breakdowns for some
of the various supplier equipment items. Suppliers publications are updated, supplemented, and
specifically amended by supplier issued revisions and service information which may be reissued by
Cessna thereby automatically amending this publication and are communicated to the field through
Cessna's Authorized Service Stations and/or through Cessna's subscription services.

B.

Inspection, maintenance and parts requirements for STC installations are not included in this manual.
When an STC installation is incorporated on the airplane, those portions of the airplane affected by
the installation must be inspected in accordance with the inspection program published by the owner
of the STC. Since STC installations may change systems interface, operating characteristics and
component loads or stresses on adjacent structures. Cessna provided inspection criteria may not be
valid for airplanes with STC installations.

C.

REVISIONS, REISSUES and TEMPORARY REVISIONS can be purchased from a Cessna Service
Station or directly from Cessna Parts Distribution, Department 701, CPD 2, Cessna Aircraft Company,
5800 East Pawnee Road, Wichita, Kansas 67218-5590.
Information in this Maintenance Manual is applicable to all U.S. and Foreign-Certified Model 172
airplanes beginning at Serial 17280001 and On, and 172S8001 and On. Information unique to a
particular country is identified in the chapter(s) affected.

D.

E.

2.

All supplemental service information concerning this manual is supplied to all appropriate Cessna
Service Stations so that they have the latest authoritative recommendations for servicing these
Cessna airplanes. Therefore, it is recommended that Cessna owners utilize the knowledge and
experience of the Cessna Service Organization.

Cross-Reference Listing of Popular Name Versus Model Numbers and Serials
A.

All airplanes, regardless of manufacturer, are certified under model number designations. However,
popular names are often used for marketing purposes. To provide a consistent method of referring
to these airplanes, the model number will be used in this publication unless the popular name is
necessary to differentiate between versions of the same basic model. The following table provides a
listing of popular names, model numbers and serial numbers.

INTRODUCTION
© Cessna Aircraft Company

Page 1
Jun 7/2004

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
NAME

MODEL

SERIALS
BEGINNING

Skyhawk

172R

17280001

Skyhawk SP

172S

172S8001

3.

Coverage and Format
A.

The Cessna Model 172 1996 And On Maintenance Manual has been prepared to assist maintenance
personnel in servicing and maintaining Model 172 airplanes (beginning at Serial 17280001 and
172S8001). This manual provides the necessary information required to enable the mechanic to
service, inspect, troubleshoot, remove and replace components or repair systems.
NOTE:

4.

B.

This manual has been prepared in accordance with the Air Transport Association (ATA) Specification
Number 100 for Manufacturer's Technical Data.

C.

Information beyond the scope of this manual may be found in the applicable Model 172 Wiring Diagram
Manual, Model 172 Illustrated Parts Catalog and the Single Engine Models 172, 182, T182, 206 and
T206, 1996 And On, Structural Repair Manual.

D.

Technical Publications are also available for the various components and systems which are not
covered in this manual. These manuals must be utilized as required for maintenance of those
components and systems, and may be purchased from the manufacturer.

Temporary Revisions
A.

5.

All Model 172 airplanes are issued a serial number. This number is assigned as construction begins
and remains with the airplane throughout its service life. This serial number appears on the airplane
ID plate, located below the horizontal stabilizer, and on a trim plate located on the pilot side doorpost.
This serial number is used to identify changes within the text or within an illustration. The absence of
a serial number in text or illustration indicates the material is applicable to all airplanes.

Material Presentation
A.

7.

Additional information which becomes available may be provided by temporary revision. This service
is used to provide, without delay, new information which will assist in maintaining safe flight/ground
operations. Temporary revisions are numbered consecutively within the ATA chapter assignment.
Page numbering utilizes the three-element number which matches the maintenance manual.
Temporary revisions are normally incorporated into the maintenance manual at the next regularly
scheduled revision.

Serialization
A.

6.

This manual is not intended to cover Model 172 airplanes produced prior to 1996. For
manuals related to these airplanes, please refer to applicable listings in the Cessna
Propeller Aircraft Care Customer Supplies and Publications Catalog.

This Maintenance Manual is available on paper, aerofiche or Compact Disc (CD/ROM). The CD/ROM
contains the Maintenance Manual, Illustrated Parts Catalog Manual, Wiring Diagram Manual and
Structural Repair Manual on a single disc.

Service Bulletins
A.

Service Bulletins have special inspections and approved modifications to the airplane and/or systems.
As service bulletins are issued, they will be included in subsequent scheduled manual revisions and
recorded in the Service Bulletin List, which is before the Introduction of the manual. The list includes:
(1) Service Bulletin Number - This Service Bulletin number column identifies the bulletin by number.
Service Bulletins are numbered to agree with ATA chapter assignment.
(2) Service Bulletin Date - The service bulletin date column gives the date the bulletin became active.
(3) Title - The title column gives the service bulletin by name. It is the same title shown on page one
of the service bulletin.
© Cessna Aircraft Company

INTRODUCTION
Page 2
Jun 7/2004

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
(4)

I
8.

Manual Incorporation - The manual incorporation column shows the date of incorporation of the
service bulletin in the maintenance manual, if applicable. If incorporation of the service bulletin
is not necessary, this column shows "No Effect" or dashed lines if the service bulletin has not
been worked.

Using the Maintenance Manual
A.

Division of Subject Matter.
(1) The Maintenance Manual is divided into four major sections. The major sections are in turn
separated into chapters, with each chapter having its own effectivity page and table of contents.
The manual divisions are as follows:
(a) Major Section 1 - Airplane General
Chapter

Title

5

Time Limits/Maintenance Checks

6

Dimensions and Areas

7

Lifting and Shoring

8

Leveling and Weighing

9

Towing and Taxiing

10

Parking, Mooring, Storage and Return to Service

11

Placards and Markings

12

Servicing

(b)

(c)

Major Section 2 - Airframe Systems
Chapter

Title

20

Standard Practices - Airframe

21

Air Conditioning

22

Auto Flight

23

Communications

24

Electrical Power

25

Equipment/Furnishings

26

Fire Protection

27

Flight Controls

28

Fuel

31

Indicating/Recording Systems

32

Landing Gear

33

Lights

34

Navigation

37

Vacuum

Major Section 3 - Structures

INTRODUCTION
© Cessna Aircraft Company

Page 3
Jun 7/2004

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Chapter

Title

51

Standard Practices and Structures - General

52

Doors

55

Stabilizers

56

Windows

57

Wings
Major Section 4 - Power Plant

(d)

B.

Chapter

Title

61

Propeller

71

Power Plant

73

Engine Fuel and Control

74

Ignition

76

Engine Controls

77

Engine Indicating

78

Exhaust

79

Oil

80

Starting

Page Numbering System.
(1) The page numbering system used in the Maintenance Manual consists of three-element
numbers separated by dashes. Refer to the example below for an illustration of typical
numbering layout as used in the ATA format.

Chapter/System
(Auto Flight)

22-10-00

Subject/Unit
(Auto Pilot)

Section/Subsystem
(Auto Pilot)

(2)
(3)
(4)
(5)

When the chapter/system element number is followed with zeros in the section/subsystem and
subject/unit element number (22-00-00), the information is applicable to the entire system.
When the section/subsystem element number is followed with zeros in the subject/unit element
number (22-10-00), the information is applicable to the subsystem within the system.
The subject/unit element number is used to identify information applicable to units within the
subsystems. The subject/unit element number progresses sequentially from the number -01 in
accordance with the number of subsystem units requiring maintenance information.
All system/subsystem/unit (chapter/section/subject) maintenance data is separated into specific
types of information: description and operation, troubleshooting, maintenance practices. Blocks
of sequential page numbers are used to identify the type of information:
Page 1 through 99 - Description and Operation

INTRODUCTION
© Cessna Aircraft Company

Page 4
Jun 7/2004

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
Page
Page
Page
Page
Page
Page
Page
Page
NOTE:

(6)

101
201
301
401
501
601
701
801

through
through
through
through
through
through
through
through

199
299
399
499
599
699
799
899

- Troubleshooting
- Maintenance Practices
- Servicing
- Removal/Installation
- Adjustment/Test
- Inspection/Check
- Cleaning/Painting
- Approved Repairs

In most cases, the individual topics have been combined into a 200-series document
(Maintenance Practices). When specific topics require lengthy explanation, they will
utilize the page blocks mentioned above.

A typical page number:

22-1 0-00 Page 202
Nov 3/97

Auto Flight

Auto Pilot

Second Page of
Auto Pilot

Date of Page Issue

Auto Pilot

(7)

9.

Effectivity Pages
A.

10.

Illustrations are also tied into the page block numbering system. For example, all illustrations
within a Maintenance Practices section will begin with the number 2 (i.e. Figure 201, Figure 202,
etc.). Conversely, all illustrations within an Approved Repair section will begin with the number
8 (i.e. Figure 801, Figure 802, etc.).

A list of effective pages is provided at the beginning of each maintenance manual chapter. All pages
in the specific chapter are listed in numerical sequence on the Effectivity Page(s) with the date of
issue for each page.

Revision Filing Instructions
A.

Regular Revision.
(1) Pages to be removed or inserted in the maintenance manual are determined by the effectivity
page. Pages are listed in sequence by the three-element number (chapter/section/subject) and
then by page number. When two pages display the same three-element number and page
number, the page with the most recent Date of Page Issue shall be inserted in the maintenance
manual. The date column on the corresponding chapter effectivity page shall verify the active
page.

B.

Temporary Revision.
(1) File temporary revisions in the applicable chapter in accordance with filing instructions appearing
on the first page of the temporary revision.
(2) The rescission of a temporary revision is accomplished by incorporation into the maintenance
manual or by a superseding temporary revision. A Record of Temporary Revisions is furnished
in the Temporary Revision List located previous to the Introduction. A Manual Incorporation Date
column on the Temporary Revision List page will indicate the date the temporary revision was
incorporated, thus authorizing the rescission of the temporary revision.

INTRODUCTION
© Cessna Aircraft Company

Page 5
Jun 7/2004

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

11.

Identifying Revised Material
A.

Additions or revisions to text in an existing section will be identified by a revision bar in the left margin
of the page and adjacent to the change.

B.

When technical changes cause unchanged text to appear on a different page(s), a revision bar will be
placed in the left margin opposite the chapter/section/subject, page number and date of all affected
pages, providing no other revision bar appears on the page. These pages will display the current
revision date in the Date of Page Issue location.

C.

Chapter 5 may contain revision bars to indicate revised text. Inspection items in section 5-10-01 are
also noted as revised, added or deleted by the date of changed item code. A revision date is indicated
below the page number.

D.

When extensive technical changes are made to text in an existing section that requires extensive
revision, revision bars will appear the full length of text.

E.

Revised and new illustrations will be indicated by either a revision bar along the side of the page or a
hand indicator directing attention to the area.

12. Warnings, Cautions and Notes
A.

Throughout the text in this manual, warnings, cautions and notes pertaining to the procedures being
accomplished are utilized. These adjuncts to the text are used to highlight or emphasize important
points. Warnings and Cautions precede the text they pertain to, and Notes follow the text they pertain
to.
(1) WARNING - Calls attention to use of materials, processes, methods, procedures or limits which
must be followed precisely to avoid injury or death to persons.
(2) CAUTION - Calls attention to methods and procedures which must be followed to avoid damage
to equipment.
(3) NOTE - Calls attention to methods which will make the job easier.

13. Propeller Aircraft Customer Care Supplies and Publications Catalog
A.

A Cessna Propeller Aircraft Customer Care Supplies and Publications Catalog is available from a
Cessna Service Station or directly from Cessna Propeller Product Support Dept.751, Cessna Aircraft
Company, P.O. Box 7706, Wichita, Kansas 67277-7706. This catalog lists all publications and
Customer Care Supplies available from Cessna for prior year models as well as new products. To
maintain this catalog in a current status, it is revised yearly and issued in paper and aerofiche form.

14. Customer Comments on Manual
A.

Cessna Aircraft Company has endeavored to furnish you with an accurate, useful and up-to-date
manual. This manual can be improved with your help. Please use the return card, provided with
your manual, to report any errors, discrepancies, and omissions in this manual as well as any general
comments you wish to make.

INTRODUCTION
© Cessna Aircraft Company

Page 6
Jun 7/2004

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
LIST OF REVISIONS
1. Revisions
A. This Maintenance Manual includes the original issue and the revisions listed in Table 1. To make
sure information in this manual is current and the latest maintenance and inspections procedures are
available, the revisions must be incorporated in the manual as they are issued.
Table 1. Basic Manual
Rei wisiofl
Number

I

-

Original Issue - 2 December 1996

Date

Writer

Revision
Number

Date

Writer

1

16 May 1997

2

6 April 1998

3

3 May 1999

4

1 August 2000

5

15 January 2001

6

18 August 2001

jgb

7

lS February 2002

jgb

8

7 April 2003

jgb

9

7 June 2004

rdg

10

3 January 2005

rdg/dll

11

1 July 2005

dll

12

2 January 2006

bjo

13

3 July 2006

bjo

14

1 January 2007

jcn

15

1 July 2007

jcn

LIST OF REVISIONS
©Cessna Aircraft Company

Page 1
Jul 1/2007

CESSNA AIRCRAIFT COMPANY

MODEL 172

MAINTENANCE MANUAL
LIST OF CHAPTERS
5
6
7
8
9
10
11

CHAPTER
Time Limits/Maintenance Checks
Dimensions and Areas
Lifting and Shoring
Leveling and Weighing
Towing and Taxiing
Parking and Mooring
Placards and Markings

12
20
21
22
23
24
25
26
27
28
31
32
33
34
37
51
52
55
56
57
61
71
73
74
76
77
78
79
80

Servicing
Standard Practices - Airframe
Air Conditioning
Auto Flight
Communications
Electrical Power
Equipment/Furnishings
Fire Protection
Flight Controls
Fuel
Indicating/Recording Systems
Landing Gear
Lights
Navigation
Vacuum
Standard Practices -Structures
Doors
Stabilizers
Windows
Wings
Propellers
Powerplant
Engine Fuel and Control
Ignition
Engine Controls
Engine Indicating
Exhaust
Oil
Starting

EFFECTIVE DATE*
Jul 1/2007
Jul 1/2007
Jan 3/2005
Jan 3/2005
Jan 3/2005
Jan 3/2005
Jan 3/2005

FICHE/FRAME
1
B2
1
E6
1
F5
1
F13
1
G2
1
G9
1
H2

Jan 1/2007
Jan 1/2007
Jan 2/2006
Jan 3/2005
Jan 1/2007
Jul 3/2006
Jan 1/2007
Jan 3/2005
Jul 1/2007
Jul 1/2007
Jan 2/2006
Jan 1/2007
Jan 2/2006
Jul 1/2007
Jan 2/2006
Jan 3/2005
Jul 3/2006
Jan 3/2005
Jan 2/2006
Jan 3/2005
Jul 1/2007
Jan 1/2007
Jan 1/2007
Jan 3/2005
Jan 2/2006
Jul 1/2007
Jan 3/2005
Jan 2/2006
Jul 1/2007

H8
A2
C12
D6
E2
E2 1
G21
Ji13
Ji19
A2
C9
D2
F2
G12
Ji13
KS
K15
L10
A2
A16
B2
B10
Cl16
D10
E2
El13
F5
F13
G5

NOTE 1: *Represents date of page one of each chapter's List of Effective Pages which is applicable to Manual
revision date.

LIST OF CHAPTERS
Q Cessna Aircrafl Company

Page 1
Jul 1/2007

CHAPTER

TIME LIMITS/
MAINTENANCE
CHECKS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INTERVAL OPERATION

REVISION
STATUS

ITEM CODE
NUMBER

TASK

Revised
Jul 1/05

246101

Essential and Crossfeed Bus Diodes - 5
Complete a check for proper operation.
Complete the Essential and Crossfeed
Bus Diode Inspection.
Refer to
Chapter 24, Essential and Crossfeed
Bus Diodes - Maintenance Practices.

20

224

Revised
Jul 3/06

251001

Seats - Examine the seats to make B
sure they are serviceable and installed
correctly. Make sure the seat stops
and adjustment mechanism operate
correctly. Examine the seat recline
control and attaching hardware to
make sure the hardware and lock
are not damaged and are correctly
installed.
Lubricate the threads of
the Seat Crank Handle Assembly
with MlIL-PRF-81 322 general purpose
grease.

1, 3

211

251002

Seat Tracks and Stops - Inspect seat B
tracks for condition and security of
installation. Check seat track stops for
damage and correct location. Inspect
seat rails for cracks.

2, 4

230

251101

Restraint System, front and rear - B
Check belts for thinning, fraying,
cutting, broken stitches, or ultra-violet
deterioration. Check system hardware
for security of installation.

1,3

211

251102

AMSAFE Aviation Inflatable Restraint 5
(AAIR) - Examine the restraint for dirt,
frayed edges, unserviceable stitching,
loose connections, and other wear.

20

211

252201

Upholstery,
Carpeting
security.

5

211

Revised
Jul 1/05

Revised
Jan 2/06

Added
May 3/99

-

Headliner, Trim,
Check condition

and
and

D

ZONE

256001

Emergency Locator Transmitter - B
Inspect for security of attachment and
check operation by verifying transmitter
output. Check cumulative time and
useful life of batteries in accordance
with 14 CFR Part 91 .207.

1, 3

310

262001

Portable Hand Fire Extinguisher - B
Inspect for proper operating pressure,
condition, security of installation, and
servicing date.

1, 3

230

262002

Cockpit Mounted Halon Type Fire P
Extinguisher - Weigh bottle. Bottle
must be reserviced by qualified
individual if more than 2 ounces is
lost.

17

211

5-10-01
0 Cessna Aircraft Company

Page 3
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

05-Title
05-List of Effective Pages
05-Record of Temporary Revisions
05-Table of Contents
5-00-00

Pages 1-2

Jul 1/2007

5-00-10

Page 1

Jan 3/2005

5-1 0-00

Pages 1-2

Jul 3/2006

5-1 0-01

Pages 1-14

Jan 3/2005

5-11 -00

Pages 1-2

Jul 1/2007

5-1 2-00

Pages 1-2

Jul 1/2007

5-1 2-01

Pages 1-6

Jul 3/2006

5-1 2-02

Pages 1-5

Jul 3/2006

5-1 2-03

Pages 1-6

Jul 3/2006

5-12-04

Pages 1-5

Jul 3/2006

5-1 2-05

Page 1

Jul 3/2006

5-1 2-07

Page 1

Jul 3/2006

5-1 2-09

Page 1

Jul 3/2006

5-12-10

Page 1

Jul 3/2006

5-12-11

Page 1

5-12-12

Page 1

Jul 3/2006
Jul 3/2006

5-12-13

Page 1

Jul 3/2006

5-12-14

Page 1

Jul 3/2006

5-12-15

Page 1

Jul 3/2006

5-12-16

Page 1

Jul 3/2006

5-12-17

Page 1

Jul 3/2006

5-12-18

Jul 3/2006

5-12-19

Page 1
Page 1

5-1 2-20

Page 1

Jul 3/2006

5-12-2 1

Page 1

Jul 3/2006

5-1 2-22

Page 1

Jul 3/2006

5-1 2-23

Page 1

Jul 3/2006

5-1 2-24

Page 1

Jul 3/2006

5-1 2-25

Page 1

Jul 3/2006

5-50-00

Pages 1-5

Jan 2/2006

Jul 3/2006

05 - LIST OF EFFECTIVE PAGES
©Cessna Aircraft Company

Page 1 of 1
Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
TIME LIMITS/MAINTENANCE CHECKS ......................
Scope....................................
Inspection Requirements...........................
Inspection Program Selection.........................
Description .................................
General Inspection Terms and Guidelines....................
AIRWORTHINESS LIMITATIONS - FAA APPROVED DATA..............
Scope....................................
Airworthiness Limitations...........................
INSPECTION TIME INTERVALS..........................
General...................................
Procedure..................................
Inspection Terms and Guidelines .......................
Chart Legend ................................

5-00-00
5-00-00
5-00-00
5-00-00
5-00-00
5-00-00

5-1 0-00
5-10-00
5-10-00
5-10-00
5-10-00

Page
Page
Page
Page
Page

1
1

INSPECTION TIME LIMITS ............................
Inspection Items...............................
COMPONENT TIME LIMITS............................
General...................................
Cessna-Supplied Replacement Time Limits ..................
Supplier-Supplied Replacement Time Limits ..................

5-10-01
5-10-01
5-11 -00
5-1 1-00
5-1 1-00
5-1 1-00

Page
Page
Page
Page
Page
Page

1
1
1
1
1
2

PROGRESSIVE CARE PROGRAM ........................
General...................................
Procedure..................................
Inspection Terms and Guidelines .......................

5-12-00
5-12-00
5-12-00
5-12-00
5-12-01
5-12-01
5-12-01

Page
Page
Page
Page
Page
Page
Page

1
1
2
2
1
1
1

5-12-02
5-12-02
5-12-02
5-12-03
5-12-03
5-12-03

Page
Page
Page
Page
Page
Page

1
1
1
1
1
1

INSPECTION OPERATION 1...........................
Description .................................
General Inspection Criteria ..........................
INSPECTION OPERATION 2 ...........................
Description .................................
General Inspection Criteria ..........................
INSPECTION OPERATION 3 ...........................
Description .................................
General Inspection Criteria ..........................

Page
Page
Page
Page
Page
Page

1
1
1
1
1
2

5-00-10 Page 1
5-00-10 Page 1
5-00-10 Page 1

1

1
1

INSPECTION OPERATION 4 ...........................
Description .................................
General Inspection Criteria ..........................

5-12-04 Page 1
5-12-04 Page 1
5-12-04 Page 1

INSPECTION OPERATION 5 ...........................
Description .................................
General Inspection Criteria ..........................
INSPECTION OPERATION 7...........................
Description .................................
General Inspection Criteria ..........................

5-12-05
5-12-05
5-12-05
5-12-07
5 12 07
5-12-07

INSPECTION OPERATION 9 ...........................
Description .................................
General Inspection Criteria ..........................

5-12-09 Page 1
5-12-09 Page 1
5-12-09 Page 1

INSPECTION OPERATION 10...........................
Description .................................
General Inspection Criteria ..........................

S-1 2-1 0 Page 1
5-12-1 0 Page 1
5-12-1 0 Page 1

05 - CONTENTS
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

INSPECTION OPERATION 12...........................
Description .................................
General Inspection Criteria ..........................

5-12-11
5-12-11
5-12-11
5-12-12
5-12-12
5-12-12

INSPECTION OPERATION 13...........................
Description .................................
General Inspection Criteria ..........................

5-12-13 Page 1
5-12-13 Page 1
5-12-13 Page 1

INSPECTION OPERATION 14...........................
Description .................................
General Inspection Criteria ..........................

5-12-14 Page 1
5-12-14 Page 1
5-12-14 Page 1

INSPECTION OPERATION 15...........................
Description .................................
General Inspection Criteria ..........................

5-12-15 Page 1
5-12-15 Page 1
5-12-15 Page 1

INSPECTION OPERATION 16...........................
Description .................................
General Inspection Criteria ..........................

5-12-16 Page 1
5-12-16 Page 1
5-12-16 Page 1

INSPECTION OPERATION 17...........................
Description .................................
General Inspection Criteria ..........................

5-12-17 Page 1
5-12-17 Page 1
5-12-17 Page 1

INSPECTION OPERATION 18...........................
Description .................................
General Inspection Criteria ..........................

5-12-18 Page 1
5-12-18 Page 1
5-12-18 Page 1

INSPECTION OPERATION 19...........................
Description .................................
General Inspection Criteria ..........................

5-12-19 Page 1
5-12-19 Page 1
5-12-19 Page 1

INSPECTION OPERATION 20...........................
Description .................................
General Inspection Criteria ..........................
INSPECTION OPERATION 21...........................
Description .................................
General Inspection Criteria ..........................

5-12-20 Page 1
5-12-20 Page 1
5-12-20 Page 1

INSPECTION OPERATION 22...........................
Description .................................
General Inspection Criteria ..........................

5-12-22 Page 1
5-12-22 Page 1
5-12-22 Page 1

INSPECTION OPERATION 23...........................
Description .................................
General Inspection Criteria ..........................

5-12-23 Page 1
5-12-23 Page 1
5-12-23 Page 1

INSPECTION OPERATION 24...........................
Description .................................
General Inspection Criteria ..........................

5-12-24 Page 1
5-12-24 Page 1
5-12-24 Page 1

INSPECTION OPERATION 25...........................
Description .................................
General Inspection Criteria ..........................

5-12-25 Page 1
5-12-25 Page 1
5-12-25 Page 1

UNSCHEDULED MAINTENANCE CHECKS ....................
General...................................
Unscheduled Maintenance Checks Defined and Areas of Inspection .......

5-50-00 Page 1
5-50-00 Page 1
5-50-00 Page 1

INSPECTION OPERATION 11...........................
Description .................................
General Inspection Criteria ..........................

1
1
1
1
1
1

5-12-21 Page 1
5-12-21 Page 1
5-12-21 Page 1

05 - CONTENTS
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
TIME LIMITS/MAINTENANCE CHECKS
1.Scope
A. This chapter provides the time limits and maintenance checks for the Model 172 airplanes. It is divided
into several sections, each with a specific purpose toward providing information necessary to establish
inspection criteria.
2.

Inspection Requirements
A. As required by U.S. Federal Aviation Regulations, all civil aircraft of U.S. registry must undergo
a complete inspection (annual) each twelve calendar months. In addition to the required annual
inspection, aircraft operated commercially (for hire) must have a complete inspection every 100
hours of operation.
B.

3.

Inspection Program Selection
A.

4.

Compliance with the regulations is accomplished using one of three methods:
(1) Traditional (Annual/1OU Hour) inspection program which utilizes 14 CFR 43, Appendix D
(scope and detail) to inspect the airplane. In addition, Cessna recommends certain components
or items be inspected at 50 hour intervals. These inspection items are listed in Inspection Time
Intervals, Section 5-10-01.
(2) Progressive Care inspection program which allows the work load to be divided into smaller
operations that can be accomplished in a shorter time period. This method is detailed in
Progressive Care Program, Section 5-12-00.
(3) PhaseCard inspection program which is geared toward high-utilization flight operations
(approximately 600 or more flight hours per year). This system utilizes 50-hour intervals
(Phase 1 and Phase 2) to inspect high-usage systems and components. At 12 months or 600
flight hours, whichever occurs first, the airplane undergoes a complete (Phase 3) inspection.
PhaseCard Inspection programs can be ordered through Propeller Aircraft Product Support,
P.O. Box 7706, Wichita, KS 67277-7706, Phone (316) 517-5800, Fax (316) 517-7271.

The selection of an inspection program (Annual, Progressive Care or PhaseCard) is primarily based
on owner/operator preferences, whether an airplane is flown for hire, and numbers of hours flown
during the year.

Description
A.

B.

Listed below is a brief description and intended purpose of each section of this chapter. For detailed
information related to each particular inspection program, refer to the specific section within this
chapter.
Section 5-00-00, Time Limits/Maintenance Checks - General. This section provides a general
overview of inspection requirements.

C.

Section 5-1 0-01, Inspection Time Intervals. The primary purpose of this section is to provide a central
location for inspection time intervals. This section may also be utilized in conjunction with 14 CFR
Part 43 to provide greater detail on inspection criteria when performing Annual/i 00-Hour inspections.

D.

Section 5-11-00, Component Time Limits. This section provides a list of components which are lifeor time-limited. Although these components are not listed in any of Cessna's inspection programs,
they must be considered and included in whatever inspection program is used.

E.

Section 5-12-00, Progressive Care Program. This section outlines the progressive inspection
program. The program is divided into four primary operations which cover all inspection requirements
up through the 200-hour interval inspection items. The remaining operations cover inspections which
are at intervals other than what the four primary operations cover. Refer to the Progressive Care
Program section for a more detailed description of the Progressive Care Program.

© Cessna Aircraft Company

5-00-00

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

5.

General Inspection Terms and Guidelines
When inspections criteria is required, this criteria is spelled out in the text. If more detailed
instructions are required for an inspection, these instructions will be referenced out to appropriate
locations (supplier publications and/or the maintenance manual).

NOTE:

A.

Definitions of terms used through the inspection programs are as follows:
(1) ON CONDITION is defined as the necessary inspections and/or checks to determine that a
malfunction or failure of the component will not occur prior to the next scheduled inspection.
(2) CONDITION is defined as inspection for (but not limited to) cleanliness, cracks, deformation,
corrosion, wear, and loose or missing fasteners.
(3) SECURITY: Inspect for looseness of fasteners and fastener securing devices such as safety
wire, coffer pins and self-locking nuts.

B.

During Inspections, use the following general guidelines:
(1) MOVABLE PARTS: Inspect for lubrication, servicing, security of attachment, binding, excessive
wear, safetying, proper operation, proper adjustment, correct travel, cracked fittings, security of
hinges, defective bearings, cleanliness, corrosion, deformation, sealing, and tension.
(2) FLUID LINES AND HOSES: Inspect for leaks, cracks, bulging, collapsed, twisted, dents, kinks,
chafing, proper radius, security, discoloration, bleaching, deterioration, and proper routing;
rubber hoses for hardness or flexibility and metal lines for corrosion.
(3) METAL PARTS: Inspect for security of attachment, cracks, metal distortion, loose or broken
terminals, heat deterioration, and corroded terminals.
(4) WIRING: Inspect for security, chafing, burning, arcing, defective insulation, loose or broken
terminals, heat deterioration, and corroded terminals.
(5) STRUCTURAL FASTENERS: Inspect for correct torque in accordance with applicable torque
values. Refer to Chapter 20, Torque Data - Maintenance Practices, during installation or when
visual inspection indicates the need for a torque check.

CAUTION: Torque values listed in this manual are not to be used for checking
tightness of installed parts during service.
FILTERS, SCREENS, AND FLUIDS: Inspect for cleanliness and the need for replacement at
specified intervals.
(7) A system check (operation or function) that requires electrical power, must be performed using
28.5 Volts, +0.25 or -1.00 Volts, bus voltage. This will make sure that all components are
(6)

I

~
C.

~~~operating
at their operational voltage.

Airplane file.
(1) Miscellaneous data, information, and licenses are a part of the airplane file. Check that the
following documents are up-to-date and in accordance with current Federal Aviation Regulations.
Most of the items listed are required by the Federal Aviation Regulations. Since the regulations
of other nations may require other documents and data, owners of airplanes operated outside
the United States should check with their own aviation officials to determine their individual
requirements.
(a) To be displayed in the airplane at all times:
1
Standard Airworthiness Certificate (FAA Form 81 00-2).
2
Aircraft Registration Certificate (FAA Form 8050-3).
3
Aircraft Radio Station License (Federal Communication Commission Form 556 if
transmitter is installed).
(b) To be carried in the airplane at all times:
.1 Weight and Balance Data Sheets and associated papers (all copies of the Repair and
Alteration Form, FAA Form 337, are applicable).
2
Equipment List.
3
Pilot's Operating Handbook and FAA Approved Airplane Flight Manual.
(c) To be made available upon request:

1

Airplane, Engine and Propeller Logbooks.

5-00-00
©Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
AIRWORTHINESS LIMITATIONS - FAA APPROVED DATA
1.

Scope
A.

2.

The Airworthiness Limitations section is FAA-approved and specifies maintenance required under
Parts 43.16 and 91.403 of Title 14 of the Code of Federal Regulations unless an alternative program
has been FAA-approved.

Airworthiness Limitations
A.

There are no airworthiness limitations associated with this airplane.

5-00-10
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION TIME INTERVALS
1.

General
A.

The primary function of this section is to give inspection time intervals. Section 5-10-01 is an index
of the inspections that you can use with 14 CFR, Part 43 inspection scope and detail. It is not
recommended, however, that you use Section 5-10-01 as the primary checklist for inspection of the
airplane.
NOTE:

2.

3.

Procedure
A.

A complete airplane inspection includes all inspection items as required by 14 CFR 43, Appendix D,
Scope and Detail of annual/100 hour inspections. Use the chart in this section as an augmentation
for the inspection.

B.

Examine the Component Time Limits section (5-11-00) with this inspection to make sure the correct
overhaul and replacement requirements are completed at the specified times.

C.

The intervals shown are recommended intervals at which items are to be examined for normal use
under average environmental conditions. Airplanes operated in extremely humid areas (tropics), or
in unusually cold, damp climates, etc., can need more frequent inspections for wear, corrosion, and
lubrication. Under these adverse conditions, complete periodic inspections related to this chart at
more frequent intervals until operator field experience is used to set individual inspection intervals.
(1) The 14 CFR Part 91 operator's inspection intervals must obey the inspection time limits shown
in this manual except as given below: (Refer to 14 CFR 91.409.)
(a) The airplane can operate only ten hours more than its inspection point, if the airplane is
enroute to a facility to have the inspection completed.
(b) If any operation is scheduled after its inspection point, the next operation in sequence keeps
the required date from the time that the late operation was originally scheduled (schedule
again if late).
(c) If any scheduled operation is completed early, and is 10 hours or less ahead of schedule,
the next scheduled phase can keep its original date.
(d) If any scheduled operation is obeyed early, and it is more than 10 hours ahead of schedule,
the next phase must be rescheduled from the time the operation was completed.

Inspection Terms and Guidelines
A.

4.

The inspection information in this section is not made to be all-inclusive. No chart can
replace the good judgment of certified Airframe and Powerplant mechanics. The owner
or operator must make sure of the airplane's airworthiness and must use only qualified
personnel to do maintenance on the airplane.

For inspection terms and guidelines, refer to Time Limits/Maintenance Checks - General.

Chart Legend
A.

Each page of the inspection given in Inspection Time Limits, Section 5-10-01, contains the five
columns that follow:
(1) REVISION STATUS - This column supplies the date that a given item was added, deleted or
revised. A blank entry in this column is an indication there have been no changes since the
original issue of this manual.
(2) INSPECTION ITEM CODE NUMBER - This column gives a six-digit number permanently
assigned to a scheduled maintenance item. A given inspection item code number will never
change and will not be used again if the scheduled maintenance item is deleted.
(3) REQUIREMENTS - This column supplies a short description of the inspection and/or servicing
procedures. Where more detailed procedure information is required, a reference will be made to
either another section in the maintenance manual or a specific reference to a supplier publication.
(4) INTERVAL - This column gives the frequency of the inspection in an alphabetic coded form. The
legend for the alpha code is shown below.

5-10-00
© Cessna Aircraft Company

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MODEL 172

MAINTENANCE MANUAL
(5)
(6)

OPERATION - The Progressive Care inspection program lets the work load to be divided into
smaller operations, that can be completed in a shorter time period. This program is supplied in
section 5-12-00, which is the Progressive Care Program.
ZONE - This column gives the locations for the components within a specific zone. For a
breakdown of how the airplane is zoned, refer to Chapter 6, Airplane Zoning - Description and
Operation.

INTERVAL
LETTER

OPERATION

A.

1, 2, 3, 4

Every 50 hours.

B.

1, 2, 3, 4

Every 100 hours.

C.

1, 2, 3, 4

Every 200 hours.

D.

5

Every 400 hours or 1 year, whichever occurs first.
(Not used. NOTE) First 100 hours and each 500 hours thereafter.

E.
F.

INTERVAL

7

Every 600 hours or 1 year, whichever occurs first.
(Not used. NOTE) Every 1000 hours or 3 years, whichever occurs first.

G.
H.

9

Every 500 hours.

I.

10

Every 1000 hours.

J.

11

Every 2 years.

K.

12

Beginning five years from the date of the manufacture, you must make
sure of the serviceability of the components every twelve months. Refer
to Airborne Air and Fuel Products Service Letter Number 39A or latest
revision.

L.

13

Every 50 hours or four months, whichever occurs first.

M.

14

Every 2 years, or anytime components are added or removed which
have the potential to affect the magnetic accuracy and/or variation of
the compass calibration, or anytime the accuracy of the compass is in
question.

N.

15

Every 2000 hours.

O.

16

Every 1000 hours or 1 year, whichever occurs first.

P.

17

Every 12 calendar months.

Q.

18

Every 6 years.

R.

19

Every 12 years.

S.

20

Every 1 year.

T.

21

Every 6 years, or every 1000 hours, whichever occurs first.

U.

22

Every 100 hours or every one year, whichever occurs first.

V.

23

Every 100 hours, every annual inspection, every overhaul, and any time
fuel lines or clamps are serviced, removed or replaced.

W.

24

First 600 hours and as defined by the manufacturer thereafter.

X.

25

Every 1000 hours or 3 years, whichever occurs first.

NOTE:

This interval is not currently used but is given to supply information only.

5-10-00
© Cessna Aircraft Company

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Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
INSPECTION TIME LIMITS
1.

Inspection Items

REVISION
STATUS

ITEM CODE
NUMBER

TASK

Revised
Jul 3/06

110000

Interior Placards, Exterior Placards, S
Decals, Markings and Identification
Plates - Examine for correct installation
and legibility. Refer to Chapter 11
Placards and Markings - Inspection/
Check.

20

All

Deleted
Jul 1/05

112101

Deleted
Jul 1/05

113101
212001

Ventilation System - Inspect clamps,
hoses, and valves for condition and
security.

D

5

211

212002

Primary Flight Display (PFD) Fan and
Multi-Function Display (MFD) Fan,
Deck Skin Fan, and Remote Avionics

U

22

220, 225

Added
Jul 1/05

Cooling

INTERVAL OPERATION

Fan - Operational

ZONE

Check.

Refer to Chapter 21, Avionics Cooling
- Maintenance Practices.

Revised
May 16/97

214001

Cold and Hot Air Hoses - Check
condition, routing, and security.

B

2, 4

120

214002

Heater Components, Inlets, and
Outlets - Inspect all lines, ducts,
clamps, seals, and gaskets for
condition, restriction, and security.

B

1, 3

211

214003

Cabin Heat and Ventilation Controls - C
Check freedom of movement through
full travel. Check friction locks for
proper operation.

1

211

221001

Autopilot Rigging - Refer to Autopilot -

F

7

610

O

16

610

O

16

610

C

3

210

Maintenance Practices.
Added
May 3/99

221002

Autopilot Servo Capstan Assemblies.
Check slip-clutch torque settings.
Refer to

Autopilot

- Maintenance

Practices.
Added
May 3/99

221003

Autopilot Servo Actuators. Inspect for
evidence of corrosion and or buildup
of dirt or other particulate matter which
may interfere with servo operation.
Refer to

Autopilot

-

Maintenance

Practices.
231001

Communication Antennas and Cables
- Inspect for security of attachment,
connection, and condition.

5-10-01
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

235001

Microphones, Headsets, and Jacks - C
Inspect for cleanliness, security, and
evidence of damage.

1

211

235002

Microphone
Push-To-Talk
Switch B
- Clean the pilot's and copilot's
microphone switches.
Refer to
Chapter 23, NAV/COM - Maintenance
Practices.

1, 3

222, 223

242001

Alternator, Mounting Bracket, and A
Electrical Connections - Check
condition and security.
Check
alternator belts for condition and proper
adjustment. Check belt tension.

1, 2, 3, 4

120

Revised
Jul 1/05

243001

Main Battery - Examine the general B
condition and security. Complete a
check of the level of electrolyte. Refer
to Chapter 12, Battery - Servicing.

2, 4

120

Revised
Jul 1/05

243002 - .

Main Battery Box and Cables - Clean
and remove any corrosion. Examine
the cables for routing, support, and
security of the connections.

2, 4

120

243003

General Airplane and System Wiring C
- Inspect for proper routing, chafing,
broken or loose terminals, general
condition, broken or inadequate
clamps, and sharp bends in wiring.

1

210

243004

External Power Receptacle and Power
Cables - Inspect for condition and
security.

2

120

243005

Standby Battery - Complete the S
Standby Battery Capacity Test. Refer
to Chapter 24, Standby Battery Maintenance Practices.

20

220

246001

Switch and Circuit Breaker Panel,
Terminal Blocks, and Junction Boxes
- Inspect wiring and terminals for
condition and security.

C

1

222

Revised
Aug 1/00

246002

Power Junction Box - Check operation
and condition. Check availability and
condition of spare fuse (if applicable).

B

1, 3

222

Added
Jul 3/06

246003

Alternator Control Unit - Complete the J
Over-voltage Protection Circuit Test.
Refer to Chapter 24, Alternator Control
Unit.

11

222

Added
Jun 7/04

Revised
Jul 1/05

INTERVAL OPERATION

B

C

ZONE

5-10-01
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

Revised
Jul 1/05

246101

Essential and Crossfeed Bus Diodes Complete a check for proper operation.
Complete the Essential and Crossfeed
Bus Diode Inspection.
Refer to
Chapter 24, Essential and Crossfeed
Bus Diodes - Maintenance Practices.

S

20

224

Revised
Jul 3/06

251001

Seats - Examine the seats to make
sure they are serviceable and installed
correctly. Make sure the seat stops
and adjustment mechanism operate
correctly. Examine the seat recline
control and attaching hardware to
make sure the hardware and lock
are not damaged and are correctly
installed.
Lubricate the threads of
the Seat Crank Handle Assembly
with MIL-PRF-81322 general purpose
grease.

B

1,3

211

251002

Seat Tracks and Stops - Inspect seat
tracks for condition and security of
installation. Check seat track stops for
damage and correct location. Inspect
seat rails for cracks.

B

2, 4

230

251101

Restraint System, front and rear - B
Check belts for thinning, fraying,
cutting, broken stitches, or ultra-violet
deterioration. Check system hardware
for security of installation.

1, 3

211

251102

AMSAFE Aviation Inflatable Restraint
(AAIR) - Examine the restraint for dirt,
frayed edges, unserviceable stitching,
loose connections, and other wear.

S

20

211

252201

Upholstery, Headliner, Trim,
Carpeting - Check condition
security.

D

5

211

256001

Emergency Locator Transmitter - B
Inspect for security of attachment and
check operation by verifying transmitter
output. Check cumulative time and
useful life of batteries in accordance
with 14 CFR Part 91.207.

1, 3

310

262001

Portable Hand Fire Extinguisher Inspect for proper operating pressure,
condition, security of installation, and
servicing date.

1, 3

230

262002

Cockpit Mounted Halon Type Fire P
Extinguisher - Weigh bottle.
Bottle
must be reserviced by qualified
individual if more than 2 ounces is
lost.

17

211

Revised
Jul 1/05

Revised
Jan 2/06

Added
May 3/99

and
and

B

5-10-01
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

Added
May 3/99

262003

Cockpit Mounted Halon Type Fire R
Extinguishers - Perform hydrostatic
test. The hydrostatic test shall be at
twelve-year intervals based on initial
servicing or date of last hydrostatic
test.

19

211

Added
May 3/99

262004

Cockpit Mounted Halon Type Fire
Extinguishers - Empty, inspect for
damage, and recharge.

Q

18

211

Revised
May 3/99

271001

Aileron Controls - Check freedom
of movement and proper operation
through full travel.

B

1, 3

120, 520,
620

271002

Ailerons and Cables - Check operation C
and security of stops. Check cables for
tension, routing, fraying, corrosion, and
turnbuckle safety. Check travel if cable
tension requires adjustment or if stops
are damaged. Check fairleads and rub
strips for condition.

3

120, 520,
620

271003

Aileron Structure, Control Rods,
Hinges, Balance Weights, Bellcranks,
Linkage, Bolts, Pulleys, and Pulley
Brackets - Check condition, operation,
and security of attachment.

B

1, 3

520, 620

271004

Ailerons and Hinges - Check condition,
security, and operation.

B

1, 3

520, 620

271005

Control Wheel Lock - Check general C
condition and operation.

1

222

271006

Control Yoke - Inspect pulleys, cables, C
bearings, and turnbuckles for condition
and security.

1

222, 223

272001

Rudder - Check internal surfaces for C
corrosion, condition of fasteners, and
balance weight attachment.

3

340

Revised
Aug 1/00

272002

Rudder - Inspect the rudder skins for B
cracks and loose rivets, rudder hinges
for condition, cracks and security;
hinge bolts, nuts, hinge bearings, hinge
attach fittings, and bonding jumper
for evidence of damage and wear,
failed fasteners, and security. Inspect
balance weight for looseness and the
supporting structure for damage.

1, 3

340

Revised
Aug 1/00

272003

Rudder, Tips, Hinges, Stops, Clips and B
Cable Attachment - Check condition,
security, and operation.

1, 3

340

Revised
May 16/97

INTERVAL OPERATION

ZONE

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MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

272004

Rudder Pedals and Linkage - Check C
for general condition, proper rigging,
and operation. Check for security of
attachment.

1

230

Added
Aug 1/00

272005

Rudder Control - Check freedom
of movement and proper operation
through full travel. Check rudder stops
for damage and security.

B

1, 3

340

Revised
Aug 1/00

273001

Elevator Control - Check freedom
of movement and proper operation
through full travel.

B

1, 3

222, 223

Revised
May 3/99

273002

Elevator Control System - Inspect B
pulleys, cables, sprockets, bearings,
chains, and turnbuckles for condition,
security, and operation. Check cables
for tension, routing, fraying, corrosion,
and turnbuckle safety.

1, 3

222,223

Revised
Aug 1/00

273003

Elevator, Hinges, Stops, and Cable B
Attachment - Check condition, security,
and operation.

1, 3

320, 330

273101

Elevator Trim System - Check cables,
push-pull rods, bellcranks, pulleys,
turnbuckles, fairleads, rub strips, etc.
for proper routing, condition, and
security.

1, 3

224, 240,
310

273102

Elevator Trim Control and Indicator C
- Check freedom of movement and
proper operation through full travel.
Check pulleys, cables, sprockets,
bearings, chains, and turnbuckles for
condition and security. Check cables
for tension, routing, fraying, corrosion,
and turnbuckle safety.

1

224, 240,
310

273103

Elevator Trim Tab and Hinges - Check
condition, security, and operation.

B

1, 3

224

Revised
Jul 3/06

273104

Elevator Trim Tab Actuator - Examine B
the free play limits.
Refer to
Chapter 27, Elevator Trim Control Maintenance Practices, Trim Tab Free
Play Inspection. If the free play is more
than the permitted limits, lubricate the
actuator and examine the free play
limits again. If the free play is still more
than the permitted limits, replace the
actuator.

1, 3

320

Deleted
Dec 1/98

273105
Elevator Trim Tab Stop Blocks - Inspect C
for damage and security.

1

240

Revised
May 3/99

273106

INTERVAL OPERATION

B

ZONE

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

Added
Jul 3/06

273107

Elevator Trim Tab Actuator - Remove, X
clean, examine, and lubricate the
actuator. Refer to Chapter 27, Elevator
Trim Control - Maintenance Practices.

25

320

Revised
Aug 1/00

275001

Flaps - Check tracks, rollers, and B
control rods for security of attachment.
Check rod end bearings for corrosion.
Check operation.

1, 3

510,610

275002

Wing Flap Control - Check operation
through full travel and observe Flap
Position indicator for proper indication.

C

1

221

275003

Flap Structure, Linkage, Bellcranks,
Pulleys, and Pulley Brackets - Check
for condition, operation and security.

C

3

510, 610

275004

Flaps and Cables - Check cables C
for proper tension, routing, fraying,
corrosion, and tumbuckle safety.
Check travel if cable tension requires
adjustment.

3

510, 610

- - - ---

INTERVAL OPERATION

ZONE

Revised
May 16/97

275005

Flap Motor, Actuator, and Limit C
Switches - Check wiring and terminals
for condition and security. Check
actuator for condition and security.

3

610

Revised
Feb 15/02

275006

Flap Actuator Threads - Clean and B
lubricate. Refer to Chapter 12, Flight
Controls - Servicing.

1, 3

610

282001

Fuel System - Inspect plumbing and B
components for mounting and security.
Fuel Tank Vent Lines and Vent Valves B
- Check vents for obstruction and
proper positioning. Check valves for
operation.

1, 3

510, 610

1, 3

510, 610

282003

Fuel Selector Valve - Check controls
for detent in each position, security of
attachment, and for proper placarding.

B

1, 3

224

282004

Integral Fuel Bays - Check for evidence
of leakage and condition of fuel caps,
adapters, and placards. Using quick
drains, ensure no contamination exists.
Check quick drains for proper shut off.

B

1, 3

510, 610

282005

Fuel Reservoir - Using quick drain,
ensure no contamination exists.

B

1, 3

510, 610

282006

Fuel Selector - Using quick drain,
ensure no contamination exists.

B

1, 3

224

Revised
Aug 1/00

Revised
Aug 1/00

282002

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

282007

Fuel Strainer, Drain Valve, and
of
- Check freedom
Controls
movement,
security,
and proper
operation. Disassemble, flush, and
clean screen and bowl.

B

1,3

510, 610

Revised
Jul 1/05

282008

Fuel Quantity Indicators - Examine for
damage and security of installation.
Complete a fuel quantity calibration
check.
Refer to Chapter 28, Fuel
Storage and Distribution - Maintenance
Practices.

F

7

220

Revised
Jul 1/05

282009

Integral Fuel Bays - Drain the fuel
(Refer to Chapter 12, Fuel - Servicing)
and purge tanks (Refer to the Single
Engine Structural Repair Manual, 1996
and On). Complete an inspection of
the tank interior and outlet screens
and remove any foreign object
debris.
Complete an inspection of
the tank interior surfaces for sealant
deterioration and corrosion (especially
in the sump areas).

I

10

510, 610

Added
Aug 1/00

282010

Auxiliary (Electric) Fuel Pump Check pump and fittings for condition,
operation, security.

B

2, 4

120

311001

Instruments - Check general condition
and markings for legibility.

B

1, 3

220

311003

Instrument Lines, Fittings, Ducting, and
Instrument Panel Wiring - Check for
proper routing, support, and security of
attachment.

C

1

220

321001

Main Landing Gear Wheel Fairings,
Strut Fairings, and Cuffs - Check for
cracks, dents, and condition of paint.

B

2, 4

721,722

321002

Main Gear Spring Assemblies Examine for cracks, dents, corrosion,
condition of paint or other damage.
Examine for chips, scratches, or other
damage that lets corrosion get to the
steel spring. Examine the axles for
condition and security.

B

2, 4

721, 722

321003

Main
Landing Gear Attachment
Structure - Check for damage, cracks,
loose rivets, bolts and nuts and security
of attachment.

B

2, 4

721,722

Deleted
Jul 1/05

Revised
Jul 1/05

311002

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© Cessna Aircraft Company

Page 7
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

Revised
Feb 15/02

ITEM CODE
NUMBER

TASK

322001

Nose Gear - Inspect torque links, B
steering rods, and boots for condition
and security of attachment. Check
strut for evidence of leakage and
proper extension.
Check strut
barrel for corrosion, pitting, and
cleanliness. Check shimmy damper
and/or bungees for operation, leakage,
and attach points for wear and security.

2, 4

720

322002

Nose Landing Gear Wheel Fairings - B
Check for cracks, dents, and condition
of paint.

2, 4

720

322003

Nose Gear Fork - Inspect for cracks, C
general condition, and security of
attachment.

4

720

322004

Nose Gear Attachment Structure - B
Inspect for cracks, corrosion, or other
damage and security of attachment.

2, 4

720

324001

Brakes - Test toe brakes and parking
brake for proper operation.

B

2, 4

230

324002

Brakes, Master Cylinders, and Parking B
Brake - Check master cylinders and
parking brake mechanism for condition
and security. Check fluid level and
test operation of toe and parking brake.
Refer to Chapter 12, Hydraulic Brakes

2, 4

224, 230

INTERVAL OPERATION

ZONE

- Servicing.

324003

Brake Lines, Wheel Cylinders, Hoses, D
Clamps, and Fittings - Check for leaks,
condition, and security and hoses for
bulges and deterioration. Check brake
lines and hoses for proper routing and
support.

5

721,722

324004

Tires - Check tread wear and general
condition. Check for proper inflation.

B

2, 4

720, 721,
722

324005

Wheels, Brake Discs, and Linings

B

2, 4

721,722

- Inspect for wear, cracks, warps,

dents, or other damage. Check wheel
through-bolts and nuts for looseness.
Revised
May 16/97

324006

Wheel Bearings - Clean, inspect and B
lube.

4

720, 721,
722

325001

Nose Gear Steering Mechanism - C
Check for wear, security, and proper
rigging.

4

720

331001

Instrument and Cabin Lights - Check B
operation, condition of lens, and
security of attachment.

1, 3

220, 211,
221

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©Cessna Aircraft Company

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Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

334001

Navigation, Beacon, Strobe, and
Landing Lights - Check operation,
condition of lens, and security of
attachment.

B

1, 3

340, 520,
620

341101

Static System - Inspect for security of C
installation, cleanliness, and evidence
of damage.

3

210

341102

Pitot and Static System - Inspect in
accordance with 14 CFR Part 91.411.

11

220

341103

Pitot Tube and Stall Warning Vane - A
Check for condition and obstructions
and verify operation of anti-ice heat.

1, 2, 3, 4

510

342101

Magnetic Compass - Inspect for
security of installation, cleanliness,
and evidence of damage.

C

1

225

Revised
May 16/97

342102

Magnetic Compass - Calibrate.

M

14

220

Revised
Aug 1/00

345001

Instrument Panel Mounted Avionics
Units (Including Audio Panel, VHF
Nav/Com(s), ADF, GPS, Transponder,
and Compass System) - Inspect for
deterioration, cracks, and security of
instrument panel mounts.
Inspect
for security of electrical connections,
condition, and security of wire routing.

C

1

225

345002

Avionics Operating Controls - Inspect
for security and proper operation of
controls and switches and ensure
that all digital segments will illuminate
properly.

C

1

225

345003

Navigation Indicators, Controls, and
Components - Inspect for condition
and security.

C

1

220, 225

345004

Navigation Antennas and Cables Inspect for security of attachment,
connection, and condition.

C

1

310

371001

Vacuum System - Inspect for condition
and security.

B

2, 4

120

371002

Vacuum Pumps - Check for condition
and security.
Check vacuum
system breather line for obstructions,
condition, and security.

B

2, 4

120

371003

Vacuum System Hoses - Inspect for
hardness, deterioration, looseness, or
collapsed hoses.

B

2, 4

120

Revised
Jan 2/06

J

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Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

Revised
May 16/97

371004

Gyro Filter - Inspect for damage,
deterioration and contamination. Clean
or replace if required.

B

2, 4

120

Deleted
Apr 7/03

371005

Revised
Jul 1/05

371006

Vacuum Manifold Check Valve - T
Complete a check for proper operation.
(Only airplanes with dual vacuum
pumps and Airborne manifolds. Refer
to the Airborne Air & Fuel Products
Service Letter Number 39A or latest
revision, and in accordance with
SB02-37-04.)
Refer to Chapter
37, Vacuum System - Maintenance
Practices for the removal and
installation of the check valve.

12

120

Added
Jan 2/06

371007
. -- --

Do an inspection of the wear indicator W
ports on the vacuum pump described in
the Tempest Service Letter 004.

24

521001

Doors - Inspect general condition. B
Check latches, hinges, and seals for
condition, operation, and security of
attachment.

1, 3

210

531001

Fuselage Surface - Inspect for skin B
damage, loose rivets, condition of
paint, and check pitot-static ports and
drain holes for obstruction. Inspect
covers and fairings for security.

1, 3

210

531002

Firewall Structure- Inspect for wrinkles, C
damage, cracks, sheared rivets, etc.
Check cowl shock mounts for condition
and security.

2

120

531003

Internal Fuselage Structure - Inspect C
bulkheads,
doorposts,
stringers,
doublers, and skins for corrosion,
cracks, buckles, and loose rivets, bolts
and nuts.

1

211

551001

Horizontal Stabilizer and Tailcone B
structure - Inspect bulkheads, spars,
ribs, and skins, for cracks, wrinkles,
loose rivets, corrosion, or other
damage. Inspect horizontal stabilizer
attach bolts for looseness. Retorque
Check security of
as necessary.
inspection covers, fairings, and tips.

1, 3

320, 330

551002

Horizontal Stabilizer and Tips - Inspect B
externally for skin damage and
condition of paint.

1, 3

320, 330

120
-

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© Cessna Aircraft Company

Page 10
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

Revised
Aug 1/00

553001

Vertical Stabilizer Fin - Inspect
bulkheads, spars, ribs, and skins
for cracks, wrinkles, loose rivets,
corrosion, or other damage. Inspect
vertical stabilizer attach bolts for
looseness. Retorque as necessary.
Check security of inspection covers,
fairings, and tip.

B

1, 3

340

Revised
Aug 1/00

553002

Vertical Stabilizer Fin and Tailcone - B
Inspect externally for skin damage and
condition of paint.

1, 3

340

561001

Windows and Windshield - Inspect
general condition.
Check latches,
hinges, and seals for condition,
operation, and security of attachment.

B

1, 3

210

571001

Wing Surfaces and Tips - Inspect
for skin damage, loose rivets, and
condition of paint.

B

1,3

510, 520,
610,620

571002

Wing Struts and Strut Fairings - Check
for dents, cracks, loose screws and
rivets, and condition of paint.

B

1,3

510,610

571003

Wing Access Plates - Check for
damage and security of installation.

C

3

510, 520,
610, 620

571004

Wing Spar and Wing Strut Fittings Check for evidence of wear. Check
attach bolts for indications of looseness
and retorque as required.

C

3

510, 520,
610,620

571005

Wing Structure - Inspect spars,
ribs, skins, and stringers for cracks,
wrinkles, loose rivets, corrosion, or
other damage.

C

3

510, 520,
610,620

611001

Spinner - Check general condition and
attachment.

A

1,2, 3, 4

110

611002

Spinner and Spinner Bulkhead Remove spinner, wash, and inspect
for cracks and fractures.

B

2, 4

110

611003

Propeller Blades - Inspect for cracks,
dents, nicks, scratches, erosion,
corrosion, or other damage.

A

1, 2, 3, 4

110

611004

Propeller
condition.

general

C

2

110

611005

Propeller Mounting - Check for security
of installation.

A

1, 2, 3, 4

110

611006

Propeller Mounting Bolts - Inspect
mounting bolts and safety wire for signs
of looseness. Retorque mounting bolts
as required.

C

2

110

Hub

-

Check

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© Cessna Aircraft Company

Page 11
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

Revised
Jul 3/06

611007

1A170E/JHA7660 propellers installed T
on Model 172R airplanes incorporating
SB02-61-02 and all Model 172S
airplanes (for airplanes operated by
pilot schools under Title 14 of the
Code of Federal Regulations, Part
141, and airplanes with more than
2000 takeoff cycles for each 1000 flight
hours) - Complete a liquid penetrant
inspection. (Refer to the latest revision
of McCauley Service Bulletin 240.)

21

110

Revised
Aug 1/00

711001

Cowling and Cowl Flaps - Inspect A
for cracks, dents, other damage and
security of cowl fasteners. Check
cowl flaps for condition, security, and
operation. Check cowl flap controls
for freedom of movement through full
travel.

1, 2, 3, 4

120

Engine Shock Mounts, Engine Mount C
Structure, and Ground Straps - Check
condition, security, and alignment.

2

120

712002

Do a check of the engine mount and A
the oil filter tube for evidence of contact.
Refer to SB99-71-02.

1, 2, 3, 4

120

716001

Alternate Induction Air System - A
Check for obstructions, operation, and
security.

1, 2, 3, 4

120

716002

Induction System - Check security of A
clamps, tubes, and ducting. Inspect for
evidence of leakage.

1, 2, 3, 4

120

Revised
Aug 1/00

716003

Induction Airbox, Valves, Doors, and A
Controls - Remove air filter and inspect
hinges, doors, seals, and attaching
parts for wear and security. Check
operation.

1, 2, 3, 4

120

Revised
May 3/99

716004

Induction Air Filter-Remove and clean. A
Inspect for damage and service.

1,2,3,4

120

Added
Jan 2/06

720000

Fuel line (Stainless steel tube V
assembly)
and support
clamp
inspection and installation. Refer to
Lycoming Service Bulletin Number
342E or later version.

23

120

722001

Engine - Inspect for evidence of oil and A
fuel leaks. Wash engine and check for
security of accessories.

1, 2, 3, 4

120

--712001

Added
Jun 7/04

--

INTERVAL OPERATION

ZONE

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©Cessna Aircraft Company

Page 12
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

REVISION
STATUS

Revised
Jul 1/05

Added
Jun 1/01

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

722002

Crankcase, Oil Sump, and Accessory
Section - Inspect for cracks and
evidence of oil leakage. Check bolts
and nuts for looseness and retorque as
necessary. Check crankcase breather
lines for obstructions, security, and
general condition.

B

2, 4

120

722003

Hoses, Metal Lines, and Fittings - A
Inspect for signs of oil and fuel leaks.
Check for abrasions, chafing, security,
proper routing and support and for
evidence of deterioration.

1, 2, 3, 4

120

723001

Engine Cylinders, Rocker Box Covers,
and Pushrod Housings - Check for fin
damage, cracks, oil leakage, security
of attachment, and general condition.

B

2, 4

120

723002

Engine Metal Lines, Hoses, Clamps,
and Fittings - Check for leaks,
condition, and security. Check for
proper routing and support.

C

2

120

723003

Engine Baffles and Seals - Check
condition and security of attachment.

A

1, 2, 3, 4

120

723004

Cylinder Compression - Complete a
differential compression test. If there
is weak cylinder compression, refer to
Chapter 71, Engine - Troubleshooting,
for further procedures.

B

2, 4

120

730001

Engine-Driven Fuel Pump - Check
for evidence of leakage, security of
attachment, and general condition.

B

2, 4

120

730002

Fuel Injection System - Check system
for security and condition. Clean fuel
inlet screen, check and clean injection
nozzles and screens (if evidence of
contamination is found), and lubricate
air throttle shaft.

B

2, 4

120

730003

Idle and Mixture - Run the airplane B
engine to determine satisfactory
performance. If required, adjust the
idle rpm and fuel mixture. Refer to
Chapter 73, Fuel Injection Systems Maintenance Practices.

2, 4

120

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Page 13
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

ZONE

Revised
Jul 1/05

741001

Magnetos - Examine the external B
condition and for correct installation
and condition of the electrical leads.
Complete a check of the engine
timing (external timing). You must
set the internal timing if the total of
all external adjustments are more
than 0.125 inch (3.17 mm) from the
original factory position, or between
each of the internal timing adjustments.
Refer to Chapter 74, Ignition System Maintenance Practices.

2, 4

120

Revised
Jul 3/06

741002

Magnetos - Clean, examine, and H
adjust as necessary. Do the 500-hour
inspection in accordance with the
Slick 4300/6300 Series Magneto
Maintenance and Overhaul Manual.

9

120

742001

Ignition Harness and Insulators-Check
for- proper routing, deterioration, and
condition of terminals.

B

2, 4

120

742002

Spark Plugs - Remove, clean, analyze, B
test, gap, and rotate top plugs to bottom
and bottom plugs to top.

2, 4

120

743001

Ignition Switch and Electrical Harness B
- Inspect for damage, condition, and
security.
Inspect and lubricate ACS brand N
ignition switch.
Refer to Chapter
74, Ignition System - Maintenance
Practices.

2, 4

120

15

224

Revised
Aug 1/00

743002

Revised
Jul 1/05

761001

Engine Controls and Linkage - A
Examine the general condition and
freedom of movement through the full
range. Complete a check for the proper
travel, security of attachment, and for
evidence of wear. Complete a check of
the friction lock and vernier adjustment
for proper operation. Complete a check
to make sure the throttle, fuel mixture,
and propeller governor arms operate
through their full arc of travel. The
maximum linear freeplay is 0.050 inch.

1, 2, 3, 4

120, 225

Revised
Aug 1/00

781001

Exhaust System - Inspect for cracks A
and security. Special check in area
of heat exchanger. Refer to Chapter
78, Exhaust system - Maintenance
Practices.

1, 2, 3, 4

120

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Page 14
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

REVISION
STATUS

ITEM CODE
NUMBER

TASK

INTERVAL OPERATION

Revised
Apr 7/03

791001

Engine Oil - Drain oil sump and oil
cooler. Check for metal particles or
foreign material in filter, on sump
drain plug, and on engine suction
screen. Replace filter, and refill with
recommended grade aviation oil.

L

13

120

792001

Oil Cooler - Check for obstructions,
leaks, and security of attachment.

A

1, 2,3, 4

120

Revised
May 3/99

801001

Starter and Electrical Connections - B
Check security and condition of starter,
electrical connection, and cable.

2, 4

120

Added
Feb 15/02

801002

Bendix Drive Starter Assembly - Clean
and lubricate starter drive assembly.

1,2,3,4

120

A

ZONE

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Page 15
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
COMPONENT TIME LIMITS
General
A. Most components given in Chapter 5 are examined as shown elsewhere in this chapter and repaired,
overhauled, or replaced as necessary. Some components have a time or life limit and must be
overhauled or replaced on or before the specified limit.
B. The terms overhaul and replacement as used in this section are defined as follows:
(1) Overhaul - Overhaul the item as given in 14 CFR 43.2 or replace it.
(2) Replacement - Replace the item with a new item or a serviceable item that is in its service life
and time limits or has been rebuilt as given in 14 CER 43.2.
C.

2.

This section (5-11 -00) gives a list of items which must be overhauled or replaced at specific time limits.
The Cessna-Supplied Replacement Time Limits section shows those items which Cessna has found
necessary to overhaul or replace at specific time limits. The Supplier-Supplied Replacement Time
Limits section shows component time limits which have been given by an outside supplier for their
products. In addition to these time limits, the components shown in this section are also examined at
regular time intervals given in the Inspection Time Intervals section. If necessary, based on service
use and inspection results, these components can be overhauled or replaced before their time limit is
reached.

Cessna-Supplied Replacement Time Limits
A.

Equipment/Furnishings (Chapter 25).
(1) 504516-401 -XXXX Restraint System, Pilot's Left Hand or Right Hand Auto Adjust every 10 years.
(2) 504851-401 -XXXX Restraint System, Pilot's Left Hand or Right Hand Manual Adjust every 10 years.
(3) 50451 6-403-XXXX Restraint System, Aft Bench Left Hand or Right Hand Auto Adjust every 10 years.
(4) 504851 -403-XXXX Restraint System, Aft Bench Left Hand or Right Hand Manual
Replace every 10 years.
(5) 2000031 -09-201 Restraint Assembly, Pilot's Seat - Replace every 10 years.
(6) 2000031-10-201 Restraint Assembly, Copilot's Seat - Replace every 10 years.
(7) 2000031-11-201 Restraint Assembly, Right Rear Seat - Replace every 10 years.
(8) 2000031-12-201 Restraint Assembly, Left Rear Seat - Replace every 10 years.

Replace
Replace
Replace
Adjust

-

B.

Flight Controls (Chapter 27).
(1) 1260074-1 Trim Tab Actuator - Replace the trim tab actuators when the free play cannot be kept
in limits by the adjustment or replacement of the rod ends, rod end bolts, screw assembly, and
the lubrication of the trim tab actuator.

C.

Vacuum (Chapter 37).
(1) 0294502-0201 Gyro Filter - Replace at 600 hours.

D.

Powerplant (Chapter 71).
(1) Engine Compartment Flexible Fluid-Carrying Teflon Hoses (Cessna-Installed), Except Drain
Hoses - Replace every 10 years or at the engine overhaul, whichever occurs first.
NOTE:

(2)
(3)

This life limit is intended not to let flexible, fluid-carrying Teflon hoses in a deteriorated
or damaged condition stay in service. Replace the flexible, fluid-carrying Teflon hoses
in the engine compartment (Cessna-installed only) every 10 years or at the engine
overhaul, whichever occurs first. This does not include drain hoses. Serviceable
hoses which are beyond these limits must be put on order immediately and replaced
within 30 days after the new hose is received from Cessna.

Engine Compartment Drain Hoses - Replace on condition.
Engine Flexible Hoses (Textron Lycoming Installed) - Refer to latest Textron Lycoming Engine
Service Bulletins.

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(4) P1 98281 Air Filter - Replace every 500 hours or if the condition of the part shows the need for
replacement.
(5) CA3559 Air Filter - Replace every 100 hours or if the condition of the part shows the need for
()replacement.
6)Mixture and.Throttle Cables - Replace at every engine TBO or any time freeplay is more than
0.05 inch.
(7) 31 B22207 Engine Starter - Replace at every engine TBO.
E.

Chapter 79 (Oil).
(1) 83278 Oil Pressure Switch - Replace every 3000 hours.
NOTE:

3.

If the 83278 Oil Pressure Switch has more than 3000 hours and is in serviceable
condition, you must submit an order for a new switch immediately and replace the
switch within 60 days after you receive it from Cessna.

Supplier-Supplied Replacement Time Limits
A.

Chapter 25 (Equipment/Furnishings).
(1) 2020-0 Pointer ELT Battery - Refer to 14 CFR 91 .207 for battery replacement time limits.
(2) 508358-409 and 508358-421 AMSAFE Aviation Inflatable Restraint (AAIR) Forward and Aft
Electronics Module Assemblies (EMA) - Remove and return the forward and aft EMA's to
AMSAFE Aviation after seven years from the manufacture date.-The expiration of the service
life, that is the total sum of storage life and installation life, must not be more than seven years
from the manufacture date. Only the manufacturer can renew the EMA's.
(3) 508792-401 and 508794-401 Pilot's, Copilot's, Left Passenger's, and Right Passenger's
AMSAFE Aviation Inflatable Restraint (AAIR) Inflator Assemblies - Remove and return the
pilot's, copilot's, left passeanger's, and right passenger's inflator assemblies to AMSAFE Aviation
after seven years from the manufacture date. The expiration of the service life, that is the
total sum of storage life and installation life, must not be more than seven years from the
manufacture date. The expiration date is found on the gas cylinder. Only the manufacturer can
renew the inflator assemblies.
(4) 452-201 -[X] CO Guardian Remote Mounted CO Detector - Replace 7 years.

B.

Chapter 28 (Fuel).
(1) Electric Fuel Pump - Replace at 10 Years if not overhauled.
Chapter 37 (Vacuum).
(1) 1H-5-25 Vacuum Manifold - Refer to the Airborne Air & Fuel Product Reference Memo No. 39 or
the latest revision for replacement time limits.
(2) B33-5-1 or ARB33-5-1 Regulator Valve Filter - Replace at 100 hours.
(3) Dry Vacuum Pump - Replace the engine-driven vacuum pump, if it does not have a wear
indicator, every 500 hours of operation, or replace the pump at the vacuum pump manufacturer's
recommended inspection and replacement interval, whichever occurs first. For vacuum pumps
with a wear indicator, replace the pump at the manufacturer's recommended inspection and
replacement interval for that vacuum pump.
(4) Airborne 350 Vacuum Pump Coupling - Replace every 6 years.

C.

D.

Chapter 61 (Propeller).
(1) 1lC235/LFA7570 orl1Al 70E/JHA7660 Propeller -Refer to the latest revision of McCauley Service
Bulletin 137 for the overhaul time limits.

E.

Chapter 71 (Powerplant).
(1) 10-360-L2A Engine - Refer to Textron/Lycoming Service Instruction S.l. 100O9AJ or latest revision
for time limits.
(2) CH48110 Engine Oil Filter - Refer to Textron/Lycoming Service Instructions S.I. 1492B, S.1.
1267C, and Service Bulletin SB.480C, or latest revisions.

F.

Chapter 74 (Ignition).
(1) 4371 Slick Magnetos
limits.

-

Refer to the Slick Service Bulletin S1B2-80C, or latest revision, for time

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MAINTENANCE MANUAL
PROGRESSIVE CARE PROGRAM
General
NOTE:

A.

B.

The inspection charts contained within the Progressive Care Program are not intended to be all
inclusive, for no such charts can replace the good judgment of a certified airframe and powerplant
mechanic in performance of his duties. As the one primarily responsible for the airworthiness
of the airplane, the owner or operator should select only qualified personnel to maintain the
airplane.
The program is divided into four primary operations (operations 1 through 4) which cover all 50hour, 100-hour and 200-hour inspection requirements. The remaining operations include all of the
inspection requirements due at other intervals.
The inspection program is divided into operations to enable the progressive inspection to be
accomplished.
OPERATION
NUMBER

INTERVAL

Operation 1

Consists of all 50-hour interval inspections items and those 100- or 200-hour
interval inspections items contained in the fuselage area.

Operation 2

Consists of all 50-hour interval inspections items and those 100- or 200-hou r
interval inspections items contained in the engine compartment area.

Operation 3

Consists of all 50-hour interval inspections items and those 100- or 200-hour
interval inspections items contained in the wing.
Consists of all 50-hour interval inspections items and those 100- or 200-hour
interval inspections items contained in the landing gear.

Operation 4
Operation 5

Every 400 hours or 1 year, whichever occurs first.

Operation 6

(Not used. NOTE) First 100 hours and each 500 hours thereafter.

Operation 7

Every 600 hours or 1 year, whichever occurs first.

Operation 8

(Not used. NOTE) Every 1000 hours or 3 years, whichever occurs first.

Operation 9

Every 500 hours.

Operation 10

Every 1000 hours.

Operation 11

Every 2 years.

Operation 12

Beginning 5 years from the date of the manufacture, you must make sure of the
serviceability of the components every twelve months. Refer to Airborne Air and
Fuel Products Service Letter Number 39A or latest revision.

Operation 13

Every 50 hours or four months, whichever occurs first.

Operation 14

Every 2 years, or anytime components are added or removed which have
the potential to affect the magnetic accuracy and/or variation of the compass
calibration, or anytime the accuracy of the compass is in question.

Operation 15

Every 2000 hours.

Operation 16

Every 1000 hours or 1 year, whichever occurs first.

Operation 17

Every 12 calendar months.

Operation 18

Every 6 years.

Operation 19

Every 12 years.

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I

OPERATION
NUMBER

INTERVAL

Operation 20

Every 1 year.

Operation 21

Every 6 years, or every 1000 hours, whichever occurs first.

Operation 22

Every 100 hours or every one year, whichever occurs first.

Operation 23
Operation 24

Every 100 hours, every annual inspection, every overhaul, and any time fuel
lines or clamps are serviced, removed or replaced.
First 600 hours and as defined by the manufacturer thereafter.

Operation 25

Every 1000 h~ours or 3 years, whichever occurs first.

NOTE:
2.

3.

This operation and interval is not currently used but is listed to provide information only.

Procedure
A.

A COMPLETE AIRPLANE INSPECTION includes all 50-, 100- and 200-hour items plus those
inspection items contained in other operations which are due at the specified time.

B.

The Component Time Limits Section (5-11 -00) should be checked at each inspection interval to ensure
proper overhaul and replacement requirements are accomplished at the specified times.

C.

The Inspection Operations have been developed based on normal usage under average
environmental conditions. Airplanes operated in extremely humid areas (tropics), or in exceptionally
cold, damp climates, etc., may need more frequent inspections for wear, corrosion, and lubrication.
Under these adverse conditions, do the periodic inspections in compliance with the Inspection
Operations at more frequent intervals until the operator can set his own inspection periods based on
field experience. The operator's inspection intervals must not deviate from the inspection time limits
shown in this manual except as given below:
(1) Each inspection interval can be exceeded by 10 hours (if time-controlled), or by 30 days (if datecontrolled), or can be performed early at any time prior to the regular interval as provided below:
(a) Inthe event of late compliance of any operation scheduled, the next operation in sequence
retains a due point from the time the late operation was originally scheduled.
(b) In the event of early compliance of any operation scheduled, that occurs 10 hours or less
ahead of schedule, the next phase due point may remain where originally set.
(c) In the event of early compliance of any operation scheduled, that occurs more than 10
hours ahead of schedule, the next operation due point must be rescheduled to establish a
new due point from the time of early accomplishment.

Inspection Terms and Guidelines
For inspection terms and guidelines, refer to Time Limits/Maintenance Checks - General.
A.

0
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MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 1
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 1 gives a list of item(s), which has all 50-hour interval inspection items and those 100- or
200-hour interval inspection items contained in the fuselage area. Items from other areas are included
to meet their required time interval.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

611001

Spinner - Check general condition and attachment.

110

611003

Propeller Blades - Inspect for cracks, dents, nicks,
scratches, erosion, corrosion, or other damage.

110

611005

Propeller Mounting
installation.

of

110

242001

Alternator,
Mounting Bracket, and Electrical
Connections - Check condition and security. Check
alternator belts for condition and proper adjustment.
Check belt tension.

120

711001

Cowling and Cowl Flaps - Inspect for cracks, dents,
other damage and security of cowl fasteners. Check
cowl flaps for condition, security, and operation.
Check cowl flap controls for freedom of movement
through full travel.

120

712002

Do a check of the engine mount and the oil filter tube
for evidence of contact. Refer to SB99-71-02.

120

-

Check

for

security

MECH INSP

REMARKS

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ITEM CODE
NUMBER

TASK

716001

Alternate Induction Air System - Check for 120
obstructions, operation, and security.

716002

Induction System - Check security of clamps, tubes,
and ducting. Inspect for evidence of leakage.

716003

Induction Airbox, Valves, Doors, and Controls - 120
Remove air filter and inspect hinges, doors, seals,
and attaching parts for wear and security. Check
operation.

716004

Induction Air Filter - Remove and clean. Inspect for 120
damage and service.

722001

Engine - Inspect for evidence of oil and fuel leaks.
Wash engine and check for security of accessories.

722003

Hoses, Metal Lines, and Fittings - Inspect for signs 120
of oil and fuel leaks. Check for abrasions, chafing,
security, proper routing and support and for evidence
of deterioration.

723003

Engine Baffles and Seals - Check condition and 120
security of attachment.

781001

Exhaust System - Inspect for cracks and security. 120
Special check in area of heat exchanger. Refer
to Chapter 78, Exhaust system - Maintenance
Practices.

792001

Oil Cooler - Check for obstructions, leaks, and 120
security of attachment.

801002

Bendix Drive Starter Assembly - Clean and lubricate
starter drive assembly.

761001

Engine Controls and Linkage - Examine the general 120, 225
condition and freedom of movement through the
full range. Complete a check for the proper travel,
security of attachment, and for evidence of wear.
Complete a check of the friction lock and vernier
adjustment for proper operation. Complete a check
to make sure the throttle, fuel mixture, and propeller
governor arms operate through their full arc of travel.
The maximum linear freeplay is 0.050 inch.

271001

Aileron Controls - Check freedom of movement and 120, 520,
proper operation through full travel.
620

243003

General Airplane and System Wiring - Inspect for 210
proper routing, chafing, broken or loose terminals,
general condition, broken or inadequate clamps, and
sharp bends in wiring.

521001

Doors - Inspect general condition. Check latches, 210
hinges, and seals for condition, operation, and
security of attachment.

ZONE

MECH INSP

REMARKS

120

120

120

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ITEM CODE
NUMBER

TASK

ZONE

531001

Fuselage Surface - Inspect for skin damage, loose
rivets, condition of paint, and check pitot-static ports
and drain holes for obstruction. Inspect covers and
fairings for security.

210

561001

Windows and Windshield - Inspect general
condition. Check latches, hinges, and seals for
condition, operation, and security of attachment.

210

214002

Heater Components, Inlets, and Outlets - Inspect
all lines, ducts, clamps, seals, and gaskets for
condition, restriction, and security.

211

214003

Cabin Heat and Ventilation Controls - Check
freedom of movement through full travel. Check
friction locks for proper operation.

211

235001

Microphones, Headsets, and Jacks - Inspect for
cleanliness, security, and evidence of damage.

211

251001

Seats - Examine the seats to make sure they are
serviceable and installed correctly. Make sure the
seat stops and adjustment mechanism operate
correctly. Examine the seat recline control and
attaching hardware to make sure the hardware and
lock are not damaged and are correctly installed.
Lubricate the threads of the Seat Crank Handle
Assembly with MIL-PRF-81322 general purpose
grease.

211

251101

Restraint System, front and rear - Check belts
for thinning, fraying, cutting, broken stitches, or
ultra-violet deterioration. Check system hardware
for security of installation.

211

531003

Internal Fuselage Structure - Inspect bulkheads,
doorposts, stringers, doublers, and skins for
corrosion, cracks, buckles, and loose rivets, bolts
and nuts.

211

311001

Instruments - Check general condition and markings
for legibility.

220

311003

Instrument Lines, Fittings, Ducting, and Instrument
Panel Wiring - Check for proper routing, support, and
security of attachment.

220

331001

Instrument and Cabin Lights - Check operation,
condition of lens, and security of attachment.

220, 211,
221

345003

Navigation Indicators, Controls, and Components - 220, 225
Inspect for condition and security.

275002

Wing Flap Control - Check operation through full
travel and observe Flap Position indicator for proper
indication.

221

246001

Switch and Circuit Breaker Panel, Terminal Blocks,
and Junction Boxes - Inspect wiring and terminals for
condition and security.

222

MECH INSP

REMARKS

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MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

246002

Power Junction Box - Check operation and 222
condition. Check availability and condition of spare
fuse (if applicable).

271005

Control Wheel Lock - Check general condition and 222
operation.

235002

Microphone Push-To-Talk Switch - Clean the pilot's 222, 223
and copilot's microphone switches. Refer to Chapter
23, NAV/COM - Maintenance Practices.

271006

Control Yoke - Inspect pulleys, cables, bearings, and 222, 223
turnbuckles for condition and security.

273001

Elevator Control - Check freedom of movement and 222, 223
proper operation through full travel.

273002

Elevator Control System - Inspect pulleys, cables, 222, 223
sprockets, bearings, chains, and turnbuckles for
condition, security, and operation. Check cables for
tension, routing, fraying, corrosion, and turnbuckle
- safety.

.- .

ZONE

273103

Elevator Trim Tab and Hinges - Check condition,
security, and operation.

282003

Fuel Selector Valve - Check controls for detent in 224
each position, security of attachment, and for proper
placarding.

282006

Fuel Selector - Using quick drain, ensure no 224
contamination exists.

273101

Elevator Trim System - Check cables, push-pull
rods, bellcranks, pulleys, turnbuckles, fairleads,
rub strips, etc. for proper routing, condition, and
security.

273102

Elevator Trim Control and Indicator - Check freedom 224, 240,
of movement and proper operation through full 310
travel. Check pulleys, cables, sprockets, bearings,
chains, and turnbuckles for condition and security.
Check cables for tension, routing, fraying, corrosion,
and turnbuckle safety.

342101

Magnetic Compass - Inspect for security of 225
installation, cleanliness, and evidence of damage.

345001

Instrument Panel Mounted Avionics Units (Including 225
Audio Panel, VHF Nav/Com(s), ADF, GPS,
Transponder, and Compass System) - Inspect
for deterioration, cracks, and security of instrument
panel mounts. Inspect for security of electrical
connections, condition, and security of wire routing.

345002

Avionics Operating Controls - Inspect for security 225
and proper operation of controls and switches
and ensure that all digital segments will illuminate
properly.

MECH INSP

REMARKS

224

224, 240,
310

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MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

262001

Portable Hand Fire Extinguisher - Inspect for
proper operating pressure, condition, security of
installation, and servicing date.

230

272004

Rudder Pedals and Linkage - Check for general
condition, proper rigging, and operation. Check for
security of attachment.

230

273106

Elevator Trim Tab Stop Blocks - Inspect for damage
and security.

240

256001

Emergency Locator Transmitter - Inspect for security
of attachment and check operation by verifying
transmitter output.
Check cumulative time and
useful life of batteries in accordance with 14 CFR
Part 91.207.

310

345004

Navigation Antennas and Cables - Inspect for
security of attachment, connection, and condition.

310

273104

Elevator Trim Tab Actuator - Examine the free
play limits. Refer to Chapter 27, Elevator Trim
Control - Maintenance Practices, Trim Tab Free
Play Inspection. If the free play is more than the
permitted limits, lubricate the actuator and examine
the free play limits again. If the free play is still more
than the permitted limits, replace the actuator.

320

273003

Elevator, Hinges, Stops, and Cable Attachment - 320, 330
Check condition, security, and operation.

551001

Horizontal Stabilizer and Tailcone structure - 320,330
Inspect bulkheads, spars, ribs, and skins, for
cracks, wrinkles, loose rivets, corrosion, or other
damage. Inspect horizontal stabilizer attach bolts for
looseness. Retorque as necessary. Check security
of inspection covers, fairings, and tips.

551002

Horizontal Stabilizer and Tips - Inspect externally for
skin damage and condition of paint.

320, 330

272002

Rudder - Inspect the rudder skins for cracks and
loose rivets, rudder hinges for condition, cracks and
security; hinge bolts, nuts, hinge bearings, hinge
attach fittings, and bonding jumper for evidence of
damage and wear, failed fasteners, and security.
Inspect balance weight for looseness and the
supporting structure for damage.

340

272003

Rudder, Tips, Hinges, Stops, Clips and Cable
Attachment - Check condition, security, and
operation.

340

272005

Rudder Control - Check freedom of movement and
proper operation through full travel. Check rudder
stops for damage and security.

340

MECH INSP

REMARKS

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MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

553001

Vertical Stabilizer Fin - Inspect bulkheads, spars,
ribs, and skins for cracks, wrinkles, loose rivets,
corrosion, or other damage.
Inspect vertical
stabilizer attach bolts for looseness. Retorque
as necessary. Check security of inspection covers,
fairings, and tip.

340

553002

Vertical Stabilizer Fin and Tailcone - Inspect
externally for skin damage and condition of paint.

340

334001

Navigation, Beacon, Strobe, and Landing Lights - 340, 520,
Check operation, condition of lens, and security of 620
attachment.

341103

Pitot Tube and Stall Warning Vane - Check for 510
condition and obstructions and verify operation of
anti-ice heat.

571001

Wing Surfaces and Tips - Inspect for skin damage,
loose rivets, and condition of paint.

275001

Flaps - Check tracks, rollers, and control rods for 510, 610
security of attachment. Check rod end bearings for
corrosion. Check operation.

282001

Fuel System - Inspect plumbing and components for 510, 610
mounting and security.

282002

Fuel Tank Vent Lines and Vent Valves - Check vents 510, 610
for obstruction and proper positioning. Check valves
for operation.

282004

Integral Fuel Bays - Check for evidence of leakage 510, 610
and condition of fuel caps, adapters, and placards.
Using quick drains, ensure no contamination exists.
Check quick drains for proper shut off.

282005

Fuel Reservoir - Using quick drain, ensure no 510, 610
contamination exists.

282007

Fuel Strainer, Drain Valve, and Controls - Check
freedom of movement, security, and proper
operation. Disassemble, flush, and clean screen
and bowl.

571002

Wing Struts and Strut Fairings - Check for dents, 510, 610
cracks, loose screws and rivets, and condition of
paint.

271003

Aileron Structure, Control Rods, Hinges, Balance
Weights, Bellcranks, Linkage, Bolts, Pulleys, and
Pulley Brackets - Check condition, operation, and
security of attachment.

271004

Ailerons and Hinges - Check condition, security, and 520, 620
operation.

275006

Flap Actuator Threads - Clean and lubricate. Refer
to Chapter 12, Flight Controls - Servicing.

MECH INSP

REMARKS

510, 520,
610, 620

510, 610

520, 620

610

***End of Operation 1 Inspection Items ***
5-12-01
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 2
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 2 gives a list of item(s), which has all 50-hour interval inspection items and those 100- or
200-hour interval inspection items contained in the engine compartment. Items from other areas are
included to meet their required time interval.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

611001

Spinner - Check general condition and attachment.

110

611002

Spinner and Spinner Bulkhead - Remove spinner,
wash, and inspect for cracks and fractures.

110

611003

Propeller Blades - Inspect for cracks, dents, nicks,
scratches, erosion, corrosion, or other damage.

110

611004

Propeller Hub - Check general condition.

110

611005

Propeller Mounting
installation.

of

110

611006

Propeller Mounting Bolts - Inspect mounting bolts
and safety wire for signs of looseness. Retorque
mounting bolts as required.

110

214001

Cold and Hot Air Hoses - Check condition, routing,
and security.

120

- Check

for

security

MECH

INSP

REMARKS

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MODEL 172

MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

242001

Alternator, Mounting Bracket, and Electrical
Connections - Check condition and security. Check
alternator belts for condition and proper adjustment.
Check belt tension.

120

243001

Main Battery - Examine the general condition and 120
security. Complete a check of the level of electrolyte.
Refer to Chapter 12, Battery - Servicing.

243002

Main Battery Box and Cables - Clean and remove
any corrosion. Examine the cables for routing,
support, and security of the connections.

120

243004

External Power Receptacle and Power Cables Inspect for condition and security.

120

282010

Auxiliary (Electric) Fuel Pump - Check pump and 120
fittings for condition, operation, security.

371001

Vacuum System - Inspect for condition and security.

120

371002

Vacuum Pumps - Check for condition and security.
Check vacuum system breather line for obstructions,
condition, and security.

120

371003

Vacuum System Hoses - Inspect for hardness,
deterioration, looseness, or collapsed hoses.

120

371004

Gyro Filter - Inspect for damage, deterioration and
contamination. Clean or replace if required.

120

531002

Firewall Structure - Inspect for wrinkles, damage,
cracks, sheared rivets, etc. Check cowl shock
mounts for condition and security.

120

711001

Cowling and Cowl Flaps - Inspect for cracks, dents,
other damage and security of cowl fasteners. Check
cowl flaps for condition, security, and operation.
Check cowl flap controls for freedom of movement
through full travel.

120

712001

Engine Shock Mounts, Engine Mount Structure,
and Ground Straps - Check condition, security, and
alignment.

120

712002

Do a check of the engine mount and the oil filter tube
for evidence of contact. Refer to SB99-71-02.

120

716001

Alternate Induction Air System - Check for
obstructions, operation, and security.

120

716002

Induction System - Check security of clamps, tubes,
and ducting. Inspect for evidence of leakage.

120

716003

Induction Airbox, Valves, Doors, and Controls - 120
Remove air filter and inspect hinges, doors, seals,
and attaching parts for wear and security. Check
operation.

716004

Induction Air Filter - Remove and clean. Inspect for
damage and service.

MECH INSP

REMARKS

120

5-12-02
© Cessna Aircraft Company

Page 2
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

722001

Engine - Inspect for evidence of oil and fuel leaks.
Wash engine and check for security of accessories.

120

722002

Crankcase, Oil Sump, and Accessory Section Inspect for cracks and evidence of oil leakage.
Check bolts and nuts for looseness and retorque
as necessary. Check crankcase breather lines for
obstructions, security, and general condition.

120

722003

Hoses, Metal Lines, and Fittings - Inspect for signs
of oil and fuel leaks. Check for abrasions, chafing,
security, proper routing and support and for evidence
of deterioration.

120

723001

Engine Cylinders, Rocker Box Covers, and Pushrod
Housings - Check for fin damage, cracks, oil
leakage, security of attachment, and general
condition.

120

723002

Engine Metal Lines, Hoses, Clamps, and Fittings Check for leaks, condition, and security. Check for
proper routing and support.

120

723003

Engine Baffles and Seals - Check condition and
security of attachment.

120

723004

Cylinder Compression - Complete a differential
compression test.
If there is weak cylinder
compression, refer to Chapter 71, Engine Troubleshooting, for further procedures.

120

730001

Engine-Driven Fuel Pump - Check for evidence
of leakage, security of attachment, and general
condition.

120

730002

Fuel Injection System - Check system for security
and condition. Clean fuel inlet screen, check and
clean injection nozzles and screens (if evidence of
contamination is found), and lubricate air throttle
shaft.

120

730003

Idle and Mixture - Run the airplane engine to
determine satisfactory performance. If required,
adjust the idle rpm and fuel mixture.
Refer to
Chapter 73, Fuel Injection Systems - Maintenance
Practices.

120

741001

Magnetos - Examine the external condition and for
correct installation and condition of the electrical
leads. Complete a check of the engine timing
(external timing). You must set the internal timing
if the total of all external adjustments are more
than 0.125 inch (3.17 mm) from the original factory
position, or between each of the internal timing
adjustments. Refer to Chapter 74, Ignition System
- Maintenance Practices.

120

742001

Ignition Harness and Insulators - Check for proper
routing, deterioration, and condition of terminals.

120

MECH INSP

REMARKS

5-12-02
© Cessna Aircraft Company

Page 3
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

742002

Spark Plugs - Remove, clean, analyze, test, gap,
and rotate top plugs to bottom and bottom plugs to
top.

120

743001

Ignition Switch and Electrical Harness - Inspect for
damage, condition, and security.

120

781001

Exhaust System - Inspect for cracks and security.
Special check in area of heat exchanger. Refer
to Chapter 78, Exhaust system - Maintenance
Practices.

120

792001

Oil Cooler - Check for obstructions, leaks, and
security of attachment.

120

801001

Starter and Electrical Connections - Check security
and condition of starter, electrical connection, and
cable.

120

801002

Bendix Drive Starter Assembly - Clean and lubricate
starter drive assembly.

120

761001

Engine Controls and Linkage - Examine the general
condition and freedom of movement through the
full range. Complete a check for the proper travel,
security of attachment, and for evidence of wear.
Complete a check of the friction lock and vernier
adjustment for proper operation. Complete a check
to make sure the throttle, fuel mixture, and propeller
governor arms operate through their full arc of travel.
The maximum linear freeplay is 0.050 inch.

120, 225

324002

Brakes, Master Cylinders, and Parking Brake
- Check master cylinders and parking brake
mechanism for condition and security. Check fluid
level and test operation of toe and parking brake.
Refer to Chapter 12, Hydraulic Brakes - Servicing.

224, 230

251002

Seat Tracks and Stops - Inspect seat tracks for
condition and security of installation. Check seat
track stops for damage and correct location. Inspect
seat rails for cracks.

230

324001

Brakes - Test toe brakes and parking brake for proper
operation.

230

341103

Pitot Tube and Stall Warning Vane - Check for
condition and obstructions and verify operation of
anti-ice heat.

510

322001

Nose Gear - Inspect torque links, steering rods,
and boots for condition and security of attachment.
Check strut for evidence of leakage and proper
extension. Check strut barrel for corrosion, pitting,
and cleanliness. Check shimmy damper and/or
bungees for operation, leakage, and attach points
for wear and security.

720

322002

Nose Landing Gear Wheel Fairings - Check for
cracks, dents, and condition of paint.

720

MECH INSP

REMARKS

5-12-02
© Cessna Aircraft Company

Page 4
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

ITEM CODE
NUMBER

TASK

ZONE

322004

Nose Gear Attachment Structure - Inspect for
cracks, corrosion, or other damage and security of
attachment.

720

324004

Tires - Check tread wear and general condition.
Check for proper inflation.

720, 721,
722

321002

Main Gear Spring Assemblies - Examine for cracks,
dents, corrosion, condition of paint or other damage.
Examine for chips, scratches, or other damage that
lets corrosion get to the steel spring. Examine the
axles for condition and security.

721,722

321003

Main Landing Gear Attachment Structure - Check
for damage, cracks, loose rivets, bolts and nuts and
security of attachment.

721,722

324005

Wheels, Brake Discs, and Linings - Inspect for wear,
cracks, warps, dents, or other damage. Check wheel
through-bolts and nuts for looseness.

721,722

321001

Main Landing Gear Wheel Fairings, Strut Fairings,
and Cuffs - Check for cracks, dents, and condition of
paint.

721,722

MECH

INSP

REMARKS

***End of Operation 2 Inspection Items ***

5-12-02
© Cessna Aircraft Company

Page 5
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 3
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 3 gives a list of item(s), which has all 50-hour interval inspection items and those 100- or
200-hour interval inspection items contained in the wing. Items from other areas are included to meet
their required time interval.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Numberfor cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

611001

Spinner - Check general condition and attachment.

110

611003

Propeller Blades - Inspect for cracks, dents, nicks,
scratches, erosion, corrosion, or other damage.

110

611005

Propeller Mounting
installation.

of

110

242001

Alternator,
Mounting Bracket,
and Electrical
Connections - Check condition and security. Check
alternator belts for condition and proper adjustment.
Check belt tension.

120

711001

Cowling and Cowl Flaps - Inspect for cracks, dents,
other damage and security of cowl fasteners. Check
cowl flaps for condition, security, and operation.
Check cowl flap controls for freedom of movement
through full travel.

120

712002

Do a check of the engine mount and the oil filter tube
for evidence of contact. Refer to SB99-71-02.

120

- Check

for

security

MECH INSP

REMARKS

5-12-03
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

716001

Alternate Induction Air System - Check for
obstructions, operation, and security.

120

716002

Induction System - Check security of clamps, tubes,
and ducting. Inspect for evidence of leakage.

120

716003

Induction Airbox, Valves, Doors, and Controls - 120
Remove air filter and inspect hinges, doors, seals,
and attaching parts for wear and security. Check
operation.

716004

Induction Air Filter - Remove and clean. Inspect for
damage and service.

722001

Engine - Inspect for evidence of oil and fuel leaks. 120
Wash engine and check for security of accessories.

722003

Hoses, Metal Lines, and Fittings - Inspect for signs
of oil and fuel leaks. Check for abrasions, chafing,
security, proper routing and support and for evidence
of deterioration.

120

723003

Engine Baffles and Seals - Check condition and
security of attachment.

120

781001

Exhaust System - Inspect for cracks and security. 120
Special check in area of heat exchanger. Refer
to Chapter 78, Exhaust system - Maintenance
Practices.

792001

Oil Cooler - Check for obstructions, leaks, and
security of attachment.

120

801002

Bendix Drive Starter Assembly - Clean and lubricate
starter drive assembly.

120

761001

Engine Controls and Linkage - Examine the general
condition and freedom of movement through the
full range. Complete a check for the proper travel,
security of attachment, and for evidence of wear.
Complete a check of the friction lock and vernier
adjustment for proper operation. Complete a check
to make sure the throttle, fuel mixture, and propeller
governor arms operate through their full arc of travel.
The maximum linear freeplay is 0.050 inch.

120, 225

271001

Aileron Controls - Check freedom of movement and 120, 520,
proper operation through full travel.
620

271002

Ailerons and Cables - Check operation and security 120, 520,
of stops. Check cables for tension, routing, fraying, 620
corrosion, and turnbuckle safety. Check travel
if cable tension requires adjustment or if stops
are damaged. Check fairleads and rub strips for
condition.

231001

Communication Antennas and Cables - Inspect for 210
security of attachment, connection, and condition.

MECH INSP

REMARKS

120

5-12-03
C Cessna Aircraft Company

Page 2
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

341101

Static System - Inspect for security of installation,
cleanliness, and evidence of damage.

210

521001

Doors - Inspect general condition. Check latches,
hinges, and seals for condition, operation, and
security of attachment.

210

531001

Fuselage Surface - Inspect for skin damage, loose
rivets, condition of paint, and check pitot-static ports
and drain holes for obstruction. Inspect covers and
fairings for security.

210

561001

Windows and Windshield - Inspect general
condition. Check latches, hinges, and seals for
condition, operation, and security of attachment.

210

214002

Heater Components, Inlets, and Outlets - Inspect
all lines, ducts, clamps, seals, and gaskets for
condition, restriction, and security.

211

251001

Seats - Examine the seats to make sure they are
serviceable and installed correctly. Make sure the
seat stops and adjustment mechanism operate
correctly. Examine the seat recline control and
attaching hardware to make sure the hardware and
lock are not damaged and are correctly installed.
Lubricate the threads of the Seat Crank Handle
Assembly with MIL-PRF-81322 general purpose
grease.

211

251101

Restraint System, front and rear - Check belts
for thinning, fraying, cutting, broken stitches, or
ultra-violet deterioration. Check system hardware
for security of installation.

211

311001

Instruments - Check general condition and markings
for legibility.

220

331001

Instrument and Cabin Lights - Check operation,
condition of lens, and security of attachment.

220, 211,
221

246002

Power Junction Box - Check operation and
condition. Check availability and condition of spare
fuse (if applicable).

222

235002

Microphone Push-To-Talk Switch - Clean the pilot's
and copilot's microphone switches. Referto Chapter
23, NAV/COM - Maintenance Practices.

222, 223

273001

Elevator Control - Check freedom of movement and
proper operation through full travel.

222, 223

273002

Elevator Control System - Inspect pulleys, cables,
sprockets, bearings, chains, and turnbuckles for
condition, security, and operation. Check cables for
tension, routing, fraying, corrosion, and turnbuckle
safety.

222, 223

273103

Elevator Trim Tab and Hinges - Check condition,
security, and operation.

224

MECH INSP

REMARKS

5-12-03
© Cessna Aircraft Company

Page 3
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

282003

Fuel Selector Valve - Check controls for detent in 224
each position, security of attachment, and for proper
placarding.

282006

Fuel Selector - Using quick drain, ensure no 224
contamination exists.

273101

Elevator Trim System - Check cables, push-pull
rods, bellcranks, pulleys, turnbuckles, fairleads,
rub strips, etc. for proper routing, condition, and
security.

262001

Portable Hand Fire Extinguisher - Inspect for 230
proper operating pressure, condition, security of
installation, and servicing date.

256001

Emergency Locator Transmitter - Inspect for security
of attachment and check operation by verifying
transmitter output. Check cumulative time and
useful life of batteries in accordance with 14 CFR
Part 91.207.

273104

Elevator Trim Tab Actuator - Examine the free 320
play limits. Refer to Chapter 27, Elevator Trim
Control - Maintenance Practices, Trim Tab Free
Play Inspection. If the free play is more than the
permitted limits, lubricate the actuator and examine
the free play limits again. If the free play is still more
than the permitted limits, replace the actuator.

273003

Elevator, Hinges, Stops, and Cable Attachment - 320, 330
Check condition, security, and operation.

551001

Horizontal Stabilizer and Tailcone structure - 320,330
Inspect bulkheads, spars, ribs, and skins, for
cracks, wrinkles, loose rivets, corrosion, or other
damage. Inspect horizontal stabilizer attach bolts for
looseness. Retorque as necessary. Check security
of inspection covers, fairings, and tips.

551002

Horizontal Stabilizer and Tips - Inspect externally for 320, 330
skin damage and condition of paint.

272001

Rudder - Check internal surfaces for corrosion,
condition of fasteners, and balance weight
attachment.

272002

Rudder - Inspect the rudder skins for cracks and 340
loose rivets, rudder hinges for condition, cracks and
security; hinge bolts, nuts, hinge bearings, hinge
attach fittings, and bonding jumper for evidence of
damage and wear, failed fasteners, and security.
Inspect balance weight for looseness and the
supporting structure for damage.

272003

Rudder, Tips, Hinges, Stops, Clips and Cable
Attachment - Check condition, security, and
operation.

ZONE

MECH INSP

REMARKS

224, 240,
310

310

340

340

5-12-03
© Cessna Aircraft Company

Page 4
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

272005

Rudder Control - Check freedom of movement and
proper operation through full travel. Check rudder
stops for damage and security.

340

553001

Vertical Stabilizer Fin - Inspect bulkheads, spars,
ribs, and skins for cracks, wrinkles, loose rivets,
corrosion, or other damage.
Inspect vertical
stabilizer attach bolts for looseness.
Retorque
as necessary. Check security of inspection covers,
fairings, and tip.

340

553002

Vertical Stabilizer Fin and Tailcone - Inspect
externally for skin damage and condition of paint.

340

334001

Navigation, Beacon, Strobe, and Landing Lights - 340, 520,
Check operation, condition of lens, and security of 620
attachment.

341103

Pitot Tube and Stall Warning Vane - Check for
condition and obstructions and verify operation of
anti-ice heat.

510

571001

Wing Surfaces and Tips - Inspect for skin damage,
loose rivets, and condition of paint.

510, 520,
610, 620

571003

Wing Access Plates - Check for damage and security
of installation.

510, 520,
610, 620

571004

Wing Spar and Wing Strut Fittings - Check for
evidence of wear. Check attach bolts for indications
of looseness and retorque as required.

510, 520,
610, 620

571005

Wing Structure - Inspect spars, ribs, skins, and
stringers for cracks, wrinkles, loose rivets, corrosion,
or other damage.

510, 520,
610, 620

275001

Flaps - Check tracks, rollers, and control rods for
security of attachment. Check rod end bearings for
corrosion. Check operation.

510, 610

275003

Flap Structure, Linkage, Bellcranks, Pulleys, and
Pulley Brackets - Check for condition, operation and
security.

510,610

275004

Flaps and Cables - Check cables for proper tension,
routing, fraying, corrosion, and turnbuckle safety.
Check travel if cable tension requires adjustment.

510, 610

282001

Fuel System - Inspect plumbing and components for
mounting and security.

510, 610

282002

Fuel Tank Vent Lines and Vent Valves - Check vents
for obstruction and proper positioning. Check valves
for operation.

510, 610

282004

Integral Fuel Bays - Check for evidence of leakage
and condition of fuel caps, adapters, and placards.
Using quick drains, ensure no contamination exists.
Check quick drains for proper shut off.

510, 610

MECH INSP

REMARKS

5-12-03
© Cessna Aircraft Company

Page 5
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
ZONE

ITEM CODE
NUMBER

TASK

282005

Fuel Reservoir - Using quick drain, ensure no 510, 610
contamination exists.

282007

Fuel Strainer, Drain Valve, and Controls - Check 510,610
freedom of movement, security, and proper
operation. Disassemble, flush, and clean screen
and bowl.

571002

Wing Struts and Strut Fairings - Check for dents, 510,610
cracks, loose screws and rivets, and condition of
paint.

271003

Aileron Structure, Control Rods, Hinges, Balance
Weights, Bellcranks, Linkage, Bolts, Pulleys, and
Pulley Brackets - Check condition, operation, and
security of attachment.

271004

Ailerons and Hinges - Check condition, security, and 520, 620
operation.

275005

Flap Motor, Actuator, and Limit Switches - Check
wiring and- terminals for condition and security.
Check actuator for condition and security.

275006

Flap Actuator Threads - Clean and lubricate. Refer 610
to Chapter 12, Flight Controls - Servicing.

MECH INSP

REMARKS

520,620

610

*** End of Operation 3 Inspection Items ***

5-12-03
© Cessna Aircraft Company

Page 6
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 4
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 4 gives a list of item(s), which has all 50-hour interval inspection items and those 100- or
200-hour interval inspection items contained in the landing gear. Items from other areas are included
to meet their required time interval.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent

conditions which can need more maintenance.
B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

611001

Spinner - Check general condition and attachment.

110

611002

Spinner and Spinner Bulkhead - Remove spinner,
wash, and inspect for cracks and fractures.

110

611003

Propeller Blades - Inspect for cracks, dents, nicks,
scratches, erosion, corrosion, or other damage.

110

611005

Propeller Mounting
installation.

of

110

214001

Cold and Hot Air Hoses - Check condition, routing,
and security.

120

242001

Alternator, Mounting Bracket, and Electrical
Connections - Check condition and security. Check
alternator belts for condition and proper adjustment.
Check belt tension.

120

243001

Main Battery - Examine the general condition and
security. Complete a check of the level of electrolyte.
Refer to Chapter 12, Battery - Servicing.

120

-

Check

for

security

MECH INSP

REMARKS

5-12-04
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

243002

Main Battery Box and Cables - Clean and remove
any corrosion. Examine the cables for routing,
support, and security of the connections.

120

282010

Auxiliary (Electric) Fuel Pump - Check pump and
fittings for condition, operation, security.

120

371001

Vacuum System - Inspect for condition and security.

120

371002

Vacuum Pumps - Check for condition and security.
Check vacuum system breather line for obstructions,
condition, and security.

120

371003

Vacuum System Hoses - Inspect for hardness,
deterioration, looseness, or collapsed hoses.

120

371004

Gyro Filter - Inspect for damage, deterioration and
contamination. Clean or replace if required.

120

711001

Cowling and Cowl Flaps - Inspect for cracks, dents,
other damage and security of cowl fasteners. Check
cowl flaps for condition, security, and operation.
Check cowl flap controls for freedom of movement
through full travel.

120

712002

Do a check of the engine mount and the oil filter tube
for evidence of contact. Refer to SB99-71-02.

120

716001

Alternate Induction Air System obstructions, operation, and security.

for

120

716002

Induction System - Check security of clamps, tubes,
and ducting. Inspect for evidence of leakage.

120

716003

Induction Airbox, Valves, Doors, and Controls Remove air filter and inspect hinges, doors, seals,
and attaching parts for wear and security. Check
operation.

120

716004

Induction Air Filter - Remove and clean. Inspect for
damage and service.

120

722001

Engine - Inspect for evidence of oil and fuel leaks.
Wash engine and check for security of accessories.

120

722002

Crankcase, Oil Sump, and Accessory Section Inspect for cracks and evidence of oil leakage.
Check bolts and nuts for looseness and retorque
as necessary. Check crankcase breather lines for
obstructions, security, and general condition.

120

722003

Hoses, Metal Lines, and Fittings - Inspect for signs
of oil and fuel leaks. Check for abrasions, chafing,
security, proper routing and support and for evidence
of deterioration.

120

723001

Engine Cylinders, Rocker Box Covers, and Pushrod
Housings - Check for fin damage, cracks, oil
leakage, security of attachment, and general
condition.

120

Check

MECH INSP

REMARKS

5-12-04
© Cessna Aircraft Company

Page 2
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

723003

Engine Baffles and Seals - Check condition and
security of attachment.

120

723004

Cylinder Compression - Complete a differential 120
compression test.
If there is weak cylinder
compression, refer to Chapter 71, Engine Troubleshooting, for further procedures.

730001

Engine-Driven Fuel Pump - Check for evidence
of leakage, security of attachment, and general
condition.

730002

Fuel Injection System - Check system for security 120
and condition. Clean fuel inlet screen, check and
clean injection nozzles and screens (if evidence of
contamination is found), and lubricate air throttle
shaft.

730003

Idle and Mixture - Run the airplane engine to 120
determine satisfactory performance. If required,
adjust the idle rpm and fuel mixture. Refer to
Chapter 73, Fuel Injection Systems - Maintenance
Practices.

741001

Magnetos - Examine the external condition and for 120
correct installation and condition of the electrical
leads. Complete a check of the engine timing
(external timing). You must set the internal timing
if the total of all external adjustments are more
than 0.125 inch (3.17 mm) from the original factory
position, or between each of the internal timing
adjustments. Refer to Chapter 74, Ignition System

MECH INSP REMARKS

120

- Maintenance Practices.

742001

Ignition Harness and Insulators - Check for proper
routing, deterioration, and condition of terminals.

742002

Spark Plugs - Remove, clean, analyze, test, gap, 120
and rotate top plugs to bottom and bottom plugs to
top.

743001

Ignition Switch and Electrical Harness - Inspect for 120
damage, condition, and security.

781001

Exhaust System - Inspect for cracks and security.
Special check in area of heat exchanger. Refer
to Chapter 78, Exhaust system - Maintenance
Practices.

120

792001

Oil Cooler - Check for obstructions, leaks, and
security of attachment.

120

801001

Starter and Electrical Connections - Check security
and condition of starter, electrical connection, and
cable.

120

801002

Bendix Drive Starter Assembly - Clean and lubricate
starter drive assembly.

120

120

5-12-04
© Cessna Aircraft Company

Page 3
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

761001

Engine Controls and Linkage - Examine the general 120, 225
condition and freedom of movement through the
full range. Complete a check for the proper travel,
security of attachment, and for evidence of wear.
Complete a check of the friction lock and vernier
adjustment for proper operation. Complete a check
to make sure the throttle, fuel mixture, and propeller
governor arms operate through their full arc of travel.
The maximum linear freeplay is 0.050 inch.

324002

Brakes, Master Cylinders, and Parking Brake 224,230
- Check master cylinders and parking brake
mechanism for condition and security. Check fluid
level and test operation of toe and parking brake.
Refer to Chapter 12, Hydraulic Brakes - Servicing.

251002

Seat Tracks and Stops - Inspect seat tracks for 230
condition and security of installation. Check seat
track stops for damage and correct location. Inspect
seat rails for cracks.

324001

Brakes - Test toe brakes and parking brake for proper
operation.

341103

Pitot Tube and Stall Warning Vane - Check for 510
condition and obstructions and verify operation of
anti-ice heat.

322001

Nose Gear - Inspect torque links, steering rods, 720
and boots for condition and security of attachment.
Check strut for evidence of leakage and proper
extension. Check strut barrel for corrosion, pitting,
and cleanliness. Check shimmy damper and/or
bungees for operation, leakage, and attach points
for wear and security.

322002

Nose Landing Gear Wheel Fairings - Check for 720
cracks, dents, and condition of paint.

322003

Nose Gear Fork - Inspect for cracks, general 720
condition, and security of attachment.

322004

Nose Gear Attachment Structure - Inspect for 720
cracks, corrosion, or other damage and security of
attachment.

325001

Nose Gear Steering Mechanism - Check for wear, 720
security, and proper rigging.

324004

Tires - Check tread wear and general condition.
Check for proper inflation.

720, 721,
722

324006

Wheel Bearings - Clean, inspect and lube.

720, 721,
722

321002

Main Gear Spring Assemblies - Examine for cracks, 721, 722
dents, corrosion, condition of paint or other damage.
Examine for chips, scratches, or other damage that
lets corrosion get to the steel spring. Examine the
axles for condition and security.

ZONE

MECH INSP

REMARKS

230

5-12-04
©Cessna Aircraft Company

Page 4
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ITEM CODE
NUMBER

TASK

ZONE

321003

Main Landing Gear Attachment Structure - Check
for damage, cracks, loose rivets, bolts and nuts and
security of attachment.

721,722

324005

Wheels, Brake Discs, and Linings - Inspect for wear,
cracks, warps, dents, or other damage. Check wheel
through-bolts and nuts for looseness.

721, 722

321001

Main Landing Gear Wheel Fairings, Strut Fairings,
and Cuffs - Check for cracks, dents, and condition of
paint.

721,722

MECH INSP

REMARKS

I

***End of Operation 4 Inspection Items ***

5-12-04
© Cessna Aircraft Company

Page 5
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 5
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 5 gives a list of item(s), which are completed every 400 hours or 1 year, whichever occurs
first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

212001

Ventilation System - Inspect clamps, hoses, and
valves for condition and security.

211

252201

Upholstery, Headliner, Trim, and Carpeting - Check
condition and security.

211

324003

Brake Lines, Wheel Cylinders, Hoses, Clamps, and
Fittings - Check for leaks, condition, and security
and hoses for bulges and deterioration. Check brake
lines and hoses for proper routing and support.

721, 722

MECH INSP

REMARKS

** End of Operation 5 Inspection Items ***

5-12-05
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 7
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 7 gives a list of item(s), which are completed every 600 hours or 1 year, whichever occurs
first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria

I

A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

I

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

282008

Fuel Quantity Indicators - Examine for damage
and security of installation. Complete a fuel quantity
calibration check. Refer to Chapter 28, Fuel Storage
and Distribution - Maintenance Practices.

220

221001

Autopilot Rigging - Refer to Autopilot - Maintenance
Practices.

610

MECH INSP

REMARKS

*** End of Operation 7 Inspection Items ***

5-12-07
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 9
Date:
Registration Number:
Serial Number:
Total Time:
1.

I
2.

Description
A.

Operation 9 gives a list of item(s), which are completed every 500 hours.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria

I

A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

I

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

I

ITEM CODE
NUMBER

TASK

ZONE

741002

Magnetos - Clean, examine, and adjust as
necessary.
Do the 500-hour inspection in
accordance with the Slick 4300/6300 Series
Magneto Maintenance and Overhaul Manual.

120

MECH INSP

REMARKS

*** End of Operation 9 Inspection Items ***

5-12-09
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 10
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 10 gives a list of item(s), which are completed every 1000 hours.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

282009

Integral Fuel Bays - Drain the fuel (Refer to Chapter
12, Fuel - Servicing) and purge tanks (Refer to the
Single Engine Structural Repair Manual, 1996 and
On). Complete an inspection of the tank interior and
outlet screens and remove any foreign object debris.
Complete an inspection of the tank interior surfaces
for sealant deterioration and corrosion (especially in
the sump areas).

510, 610

MECH

INSP

REMARKS

*** End of Operation 10 Inspection Items ***

5-12-10
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 11
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 11 gives a list of item(s), which are completed every 2 years.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

341102

Pitot and Static System - Inspect in accordance with
14 CFR Part 91.411.

220

246003

Alternator Control Unit - Complete the Over-voltage
Protection Circuit Test.
Refer to Chapter 24,
Alternator Control Unit.

222

MECH INSP

REMARKS

*** End of Operation 11 Inspection Items **

5-12-11
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 12
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 12 gives a list of item(s), which are completed beginning five years from the date of the
manufacture. You must make sure of the serviceability of the components every twelve months. Refer
to Airborne Air and Fuel Products Service Letter Number 39A or latest revision.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Numberfor cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

371006

Vacuum Manifold Check Valve - Complete a check
for proper operation.
(Only airplanes with dual
vacuum pumps and Airborne manifolds. Refer to
the Airborne Air & Fuel Products Service Letter
Number 39A or latest revision, and in accordance
with SB02-37-04.) Refer to Chapter 37, Vacuum
System - Maintenance Practices for the removal
and installation of the check valve.

120

MECH INSP

REMARKS

***End of Operation 12 Inspection Items ***

5-12-12
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 13
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 13 gives a list of item(s), which are completed every 50 hours or four months, whichever
occurs first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Numberfor cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria

I

A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

I

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

791001

Engine Oil - Drain oil sump and oil cooler. Check for
metal particles or foreign material in filter, on sump
drain plug, and on engine suction screen. Replace
filter, and refill with recommended grade aviation oil.

120

MECH INSP

REMARKS

***End of Operation 13 Inspection Items ***

5-12-13
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 14
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 14 gives a list of item(s), which are completed every 2 years, or anytime components are
added or removed from the airplane which have the potential to affect the magnetic accuracy and/or
variation of the compass calibration, or anytime the accuracy of the compass is in question.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent

conditions which can need more maintenance.
B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

342102

Magnetic Compass - Calibrate.

220

MECH INSP

REMARKS

***End of Operation 14 Inspection Items ***

5-12-14
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 15
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 15 gives a list of item(s), which are completed every 2000 hours.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

743002

Inspect and lubricate ACS brand ignition switch.
Refer to Chapter 74, Ignition System - Maintenance
Practices.

224

MECH INSP

REMARKS

***End of Operation 15 Inspection Items ***

5-12-15
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 16
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 16 gives a list of item(s), which are completed every 1000 hours or 1 year, whichever occurs
first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

221002

Autopilot Servo Capstan Assemblies.
Check 610
slip-clutch torque settings. Refer to Autopilot Maintenance Practices.

221003

Autopilot Servo Actuators. Inspect for evidence of
corrosion and or buildup of dirt or other particulate
matter which may interfere with servo operation.
Refer to Autopilot - Maintenance Practices.

ZONE

MECH

INSP

REMARKS

610

***End of Operation 16 Inspection Items ***

5-12-16
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 17
Date:
Registration Number:
Serial Number:
Total Time:
1.

I
2.

Description
A.

Operation 17 gives a list of item(s), which are completed every 12 calendar months.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria

I

A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

I

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.
ZONE

ITEM CODE
NUMBER

TASK

262002

Cockpit Mounted Halon Type Fire Extinguisher - 211
Weigh bottle. Bottle must be reserviced by qualified
individual if more than 2 ounces is lost.

MECH INSP

REMARKS

***End of Operation 17 Inspection Items ***

5-12-17
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 18
Date:
Registration Number:
Serial Number:
Total Time:
1.

I
2.

I

Description
A.

Operation 18 gives a list of item(s), which are completed every 6 years.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

262004

Cockpit Mounted Halon Type Fire Extinguishers - 211
Empty, inspect for damage, and recharge.

ZONE

MECH INSP

REMARKS

***End of Operation 18 Inspection Items ***

5-12-18
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 19
Date:
Registration Number:
Serial Number:
Total Time:
1.

I
2.

Description
A.

Operation 19 gives a list of item(s), which are completed every 12 years.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria

I

A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

I

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

262003

Cockpit Mounted Halon Type Fire Extinguishers - 211
Perform hydrostatic test. The hydrostatic test shall
be at twelve-year intervals based on initial servicing
or date of last hydrostatic test.

ZONE

MECH INSP

REMARKS

***End of Operation 19 Inspection Items ***

5-12-19
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 20
Date:
Registration Number:
Serial Number:
Total Time:
1.

Description
A.

Operation 20 gives a list of item(s), which are completed every year.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Numberfor cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.
The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

C.
2.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

251102

AMSAFE Aviation Inflatable Restraint (AAIR) - 211
Examine the restraint for dirt, frayed edges,
unserviceable stitching, loose connections, and
other wear.

243005

Standby Battery - Complete the Standby Battery
Capacity Test. Refer to Chapter 24, Standby Battery

ZONE

MECH INSP

REMARKS

220

- Maintenance Practices.

246101

Essential and Crossfeed Bus Diodes - Complete a 224
check for proper operation. Complete the Essential
and Crossfeed Bus Diode Inspection. Refer to
Chapter 24, Essential and Crossfeed Bus Diodes Maintenance Practices.

110000

Interior Placards, Exterior Placards, Decals, All
Markings and Identification Plates - Examine for
correct installation and legibility. Refer to Chapter
11 Placards and Markings - Inspection/Check.
***End of Operation 20 Inspection Items **

5-12-20
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 21
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 21 gives a list of item(s), which are completed every 6 years, or every 1000 hours, whichever
occurs first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

611007

1A170E/JHA7660 propellers installed on Model
172R airplanes incorporating SB02-61-02 and all
Model 172S airplanes (for airplanes operated by
pilot schools under Title 14 of the Code of Federal
Regulations, Part 141, and airplanes with more
than 2000 takeoff cycles for each 1000 flight hours)
- Complete a liquid penetrant inspection. (Refer
to the latest revision of McCauley Service Bulletin
240.)

110

MECH INSP

REMARKS

*** End of Operation 21 Inspection Items ***

,

© Cessna Aircraft Company

5-12-21

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 22
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 22 consists of items to be inspected every 100 hours or every one year, whichever occurs
first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

212002

Primary Flight Display (PFD) Fan and Multi-Function
Display (MFD) Fan, Deck Skin Fan, and Remote
Avionics Cooling Fan - Operational Check. Refer
to Chapter 21, Avionics Cooling - Maintenance
Practices.

220, 225

MECH INSP

REMARKS

***End of Operation 22 Inspection Items **

5-12-22
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 23
Date:

Registration Number:
Serial Number:
Total Time:
1.

2.

*I

Description
A.

Operation 23 gives a list of item(s), which are completed every 100 hours, every annual inspection,
every overhaul, and any time fuel lines or clamps are serviced, removed, or replaced.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

720000

Fuel line (Stainless steel tube assembly) and support
clamp inspection and installation. Refer to Lycoming
Service Bulletin Number 342E or later version.

120

MECH INSP

REMARKS

***End of Operation 23 Inspection Items ***

5-12-23
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 24
Date:
Registration Number:
Serial Number:
Total Time:
1.

I
2.

Description
A.

Operation 24 gives a list of item(s), which are completed the first 600 hours and as defined by the
manufacturer thereafter.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria

I

A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

I

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

371007

Do an inspection of the wear indicator ports on the
vacuum pump described in the Tempest Service
Letter 004.

120

MECH INSP

REMARKS

***End of Operation 24 Inspection Items ***

5-12-24
O Cessna Aircraft Company

Page 1
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INSPECTION OPERATION 25
Date:
Registration Number:
Serial Number:
Total Time:
1.

2.

Description
A.

Operation 25 gives a list of item(s), which are completed every 1000 hours or 3 years, whichever
occurs first.

B.

Inspection items are given in the order of the zone in which the inspection is to be completed. A
general description of the inspection required and the Item Code Number for cross-reference to section
5-10-01 are shown. Frequently, the tasks define more specifically the scope and extent of each
required inspection. These tasks are printed in the individual chapters of this manual.

C.

The right portion of each page gives space for the mechanic's and inspector's initials and remarks. A
copy of these pages can be used as a checklist when these inspections are completed.

General Inspection Criteria
A.

During each of the specified inspection tasks in this section, more general inspections of the adjacent
areas must be done while access is available. These general inspections are used to find apparent
conditions which can need more maintenance.

B.

If a component or system is changed after a required task has been completed, then that specified
task must be done again to make sure it is correct before the system or component is returned to
service.

C.

Do a preflight inspection after these inspections are completed to make sure all the required items
are correctly serviced. Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual.

ITEM CODE
NUMBER

TASK

ZONE

273107

Elevator Trim Tab Actuator - Remove, clean,
examine, and lubricate the actuator.
Refer to
Chapter 27, Elevator Trim Control - Maintenance
Practices.

320

MECH INSP

REMARKS

***End of Operation 25 Inspection Items ***

5-12-25
© Cessna Aircraft Company

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
UNSCHEDULED MAINTENANCE CHECKS
1.

General
A.

During operation, the airplane can go through:
(1) Hard landings.
(2) Overspeed.
(3) Extreme turbulence or extreme maneuvers.
(4) Towing with a large fuel unbalance or high drag/side loads due to ground handling.
(5) Lightning strikes.

B.

When the flight crew gives a report of any of these conditions, complete a visual inspection of the
airframe and specific inspections of components and areas involved.

C.

Do the inspections to find and examine the damage in local areas of visible damage, and in the
structure and components adjacent to the area of damage.
If foreign object damage (FOD) is found, complete a visual inspection of the airplane before the
airplane is returned to service.

D.
2.

Unscheduled Maintenance Checks Defined and Areas of Inspection
A.

Hard/Overweight Landings.
(1) A hard landing is any landing made when the sink rate is more than the permitted sink rate limit.
An overweight landing is any landing made when the gross weight is more than the maximum
gross landing weight given in the approved Pilot's Operating Handbook.
NOTE:

If the hard/overweight landing also has high drag/side loads, more checks are
necessary.

(2) Hard or overweight landing check.
(a) Landing gear.
1
Main gear struts - Examine for correct attachment and permanent set.
2
Main gear attachments and supporting structure - Examine for loose or unserviceable
fasteners and signs of structural damage.
3
Nose gear trunnion supports and attaching structure - Examine for loose or
unserviceable fasteners and signs of structural damage.
4
Nose gear attachments and supporting structure - Examine for loose or unserviceable
fasteners and signs of structural damage.
(b) Wings.
1
Wing surface and lift strut - Examine the skin for buckles, loose or unserviceable
fasteners, and fuel leaks. Examine the attach fittings for security.
2
Trailing edge - Examine for any deformation that stops the normal flap operation.
B.

Overspeed.
(1) Overspeed occurs when one of the conditions that follow are met:
(a) The airplane was flown at a speed more than the speed limit of the flaps.
(b) The airplane was flown at a speed more than the maximum design speed.
(2) Overspeed (airspeed) check.
(a) Fuselage.
1
Windshield and Windows - Examine for buckling, dents, loose or unserviceable
fasteners, and signs of structural damage.
2
All hinged doors - Examine the hinges, hinge attach points, latches and attachments,
and skins for deformation and signs of structural damage.
(b) Cowling.
1
Skins - Examine for buckling, cracks, loose or unserviceable fasteners, and signs of
structural damage.

5-50-00
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(c)

Stabilizers.
Stabilizers - Examine the skins, hinges and attachments, movable surfaces, mass
1
balance weights, and the structure for cracks, dents, buckling, loose or unserviceable
fasteners, and signs of structural damage.
(d) Wings.
Flaps - Examine the skin for buckling, cracks, loose or unserviceable fasteners,
1
attachments, and signs of structural damage.
Fillets and fairings - Examine for buckling, dents, cracks, and loose or unserviceable
2
fasteners.

C.

Extreme Turbulence or Extreme Maneuvers.
(1) Extreme turbulence is caused by atmospheric conditions that produce dangerous quantities of
stress on the airplane. Extreme maneuvers are any maneuvers that do not stay within the limits
given in the Pilot's Operating Handbook.
(2) Extreme turbulence and/or maneuvers checks.
(a) Stabilizers.
1
Horizontal stabilizer hinge fittings, actuator fittings, and stabilizer center section Examine for loose or unserviceable fasteners and signs of structural damage.
Vertical stabilizer - Examine the vertical stabilizer for signs of structural damage, skin
2
buckles, loose or unserviceable fasteners, and damage to the hinges and actuator
fittings.
Elevator and rudder balance weight supporting structure - Examine for loose or
3
unserviceable fasteners and signs of structural damage.
(b) Wing.
1
Wing to body strut fittings and supporting structure - Examine for loose or
unserviceable fasteners and signs of structural damage.
Trailing Edge - Examine for any deformation that stops the normal operation of the
2
flap and aileron.

D.

Lightning Strike.
(1) If the airplane is flown through an electrically charged region of the atmosphere, it can be struck
by an electrical discharge moving from cloud to cloud or from cloud to ground. During a lightning
strike, the current goes into the airplane at one point and comes out of another, usually at
opposite extremities. The wing tips, nose and tail sections are the areas where damage is
most likely to occur. You can find burns and/or erosion of small surface areas of the skin and
structure during inspection. In most cases, the damage is easily seen. In some cases, however,
a lightning strike can cause damage that is not easily seen. The function of the lightning strike
inspection is to find any damage to the airplane before it is returned to service.
(2) Lightning strike check. As the checks that follow are performed, complete the Lightning Strike/
Static Discharge Incident Reporting Form and return it to Cessna Propeller Aircraft Product
Support Dept. 751, Cessna Aircraft Company, P.O. Box 7706, Wichita, KS. 67277-7706. If
there are components listed on the form that are not applicable to your airplane, please write
"Not Applicable" in the space provided.
(a) Communications.
1
Antennas - Examine all antennas for burns or erosion. If you find damage, complete
the functional test of the communication system.
(b) Navigation.
1
Glideslope antenna - Examine for burning and pitting. If damage is found, complete
a functional check of the glideslope system.
Compass - The compass is serviceable if the corrected heading is within plus or minus
2
10 degrees of the heading shown by the remote compass system. Remove, repair,
or replace the compass if the indication is not within the tolerance limits.
(c) Fuselage.
Skin - Examine the surface of the fuselage skin for signs of damage.
1
2
Tailcone - Examine the tailcone and static dischargers for damage.
(d) Stabilizers.
1
Examine the surfaces of the stabilizers for signs of damage.
(e) Wings.
Skins - Examine the skin for burns and erosion.
1
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©Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
2
Wing tips - Examine the wing tips for burns and pits.
3
Flight surfaces and hinging mechanisms - Examine for burns and pits.
(f) Propeller.
1
Propeller - Remove the propeller and have it examined at an authorized repair station.
(g) Powerplant.
1
Engine - Refer to the engine manufacturer's overhaul manual for inspection
procedures.
E.

Foreign Object Damage.
(1) Foreign object damage (FOD) is damage to the airplane caused by a bird strike or by any other
foreign object while operating the airplane on the ground or in normal flight. Tools, bolts, nuts,
washers, rivets, rags or pieces of safety-wire left in the aircraft during maintenance operations
can also cause damage. The function of the foreign object damage inspection is to find any
damage before the airplane is repaired or returned to service.
(2) Use caution to prevent unwanted objects from hitting the airplane during towing and at all times
when the airplane is not in service.
(3) The aerodynamic cleanliness level (degree of surface smoothness), has an effect on the
performance of the airplane. It is important to keep a high level of cleanliness.
(4) Normal operation or careless maintenance operations can cause contour distortion of the
aerodynamic surface. Careless maintenance operations can also cause distortion to the doors
and access panels. Be careful when you work with these items.
(5) Foreign object damage check.
(a) Landing gear.
1
Fairings - Examine for dents, cracks, misalignment, and signs of structural damage.
(b) Fuselage.
1
Skin - Examine the forward and belly areas for dents, punctures, cracks, and signs
of structural damage.
(c) Cowling.
1
Skins - Examine for dents, punctures, loose or unserviceable fasteners, cracks, and
signs of structural damage.
(d) Stabilizers.
1
Leading edge skins - Examine for dents, cracks, scratches, and signs of structural
damage.
(e) Windows.
1
Windshield - Examine for pits, scratches, and cracks.
(f) Wings.
1
Leading edge skins - Examine for dents, cracks, punctures, and signs of structural
damage.
(g) Engine.
1
Propeller - Examine the propeller for nicks, bends, cracks, and worn areas on the
blades.

F.

High Drag/Side Loads Due To Ground Handling.
(1) A high drag/side load condition occurs when the airplane skids or overruns the prepared surface
and goes onto an unprepared surface. It also includes landings that are short of the prepared
surface, or landings which involve the damage of tires or skids on a runway to the extent that the
safety of the airplane is in question. This includes takeoff and landings or unusual taxi conditions.
(2) High drag/side loads due to ground handling check.
(a) Landing gear.
1
Main gear and fairings - Examine for loose or unserviceable fasteners, buckling,
cracks, and signs of structural damage.
2
Nose gear and fairing - Examine for loose or unserviceable fasteners, cracks, loose
steering cable tension, buckling, and signs of structural damage.
(b) Wings.
1
Wing to fuselage attach fittings and attaching structure - Examine for loose or
unserviceable fasteners and signs of structural damage.

5-50-00
© Cessna Aircraft Company

Page 3

Jan 2/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B4224

1.

LIGHTNING STRIKE/STATIC DISCHARGE INCIDENT REPORTING FORM
Part 1

Flight Crew must complete Part 1.
NOTE:

A.

B.

Entire report must be filled out following any lightning strike incident. If lightning strike is
discovered after the fact, complete as much of report as possible. File form immediately
following incident. Attach additional sheet(s) to provide complete description.

Flight Information:
Flight Number

_

Altitude

ft

Strike Date_

Airspeed

Model

knots

Unit/Serial Number

Geographical Location

Airplane Orientation:
Takeoff __
Approach

Climb
Other

_

Cruise

Descent

C. At time of Strike, aircraft was:
Above Clouds__ Within Clouds __

Below Ceiling

D. Precipitation at Strike:
Rain

Sleet

Hail

Snow

None

E. Lightning in Vicinity:
Before

F

None

Static in Comm/Nav
Before

G.

After

After

None

Was St. Elmo's fire (bluish electrical discharge or corona) visible before strike?
Yes __

No

H. Interference (I) or Outage (0) report. Check all the following which apply, and list affected systems,
such as dimming of cabin lights, total system outage, etc.
Engines
I
Navigation
I
Communication
O
Flight Instruments
I
Flight Control
I
AC Power System
I
DC Power System
I
I.

Additional comments and descriptions:

Part 1 completed by:

Date

© Cessna Aircraft Company

Phone

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
B4225

1.

LIGHTNING STRIKE/STATIC DISCHARGE INCIDENT REPORTING FORM
Part 2
Ground Crew must complete Part 2.
NOTE:

Attach additional sheet(s) to provide complete description. Photos and sketches of damage
are recommended and must be itemized and referenced in their description.

NOTE:

If damage is severe, please report the lightning strike as soon as possible. Inspection by
Cessna Engineering Representative(s) may be required.

A.

List any sweeping points, such as burn marks, divots, etc., and skin penetrations on airplane
skin believed to be the result of the lightning strike. Itemize and reference location(s) of damage
on drawing provided. Indicate top, bottom, left or right.

r1I

B.

1.1

1.

Describe damage to structure and external components caused by previously mentioned
damage points. In the case of skin penetration(s), indicate hole diameter(s). List all damage to
radome and any other composite structure, such as fairings, control surfaces, etc. If lightning
diverter strips are damaged, include lightning diverter strip location(s) on radome. For damage to
composite structure, paint thickness must be included in description.

C. List any damage to avionics and electrical components believed to be the result of the lightning
strike, including damaged wiring, disengaged circuit breakers, etc. Include manufacturer, model
number and serial number of damaged units where applicable.
D. Estimate cost of repair.
E. Mention severity of damage (light, moderate, heavy).
F. Additional comments and descriptions:
Part 2 completed by:

Date

Phone

5-50-00
© Cessna Aircraft Company

Page 5

Jan 2/2006

CHAPTER

DIMENSIONS AND
AREAS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

6-00-00

Page 1

Apr 7/2003

6-10-00

Pages 1-4

Apr 7/2003

6-15-00

Pages 1-3

Apr 7/2003

6-2000

Pages 1-4
Pages 1-11

Jul 1/2007

06-Title
06-List of Effective Pages
06-Record of Temporary Revisions
06-Table of Contents

6-20-02

©Cessna Aircraft Company

06

-

Jul 1/2007

LIST OF EFFECTIVE PAGES

Page 1 of 1
Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
DIMENSIONS AND AREAS - GENERAL ......................
Scope... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Definition ..................................
AIRPLANE DIMENSIONS AND SPECIFICATIONS - DESCRIPTION AND OPERATION
General...................................
AIRPLANE STATIONS - DESCRIPTION AND OPERATION..............
General...................................
AIRPLANE ZONING - DESCRIPTION AND OPERATION...............
General...................................
Description .................................
ACCESS/INSPECTION PLATES - DESCRIPTION AND OPERATION.........
General...................................
Access/Inspection Panel Numbering......................
Description .................................

© Cessna Aircraft Company

6-00-00 Page 1
6-00-00 Page 1
6-00-00 Page 1
6-1 0-00 Page 1
6-1 0-00 Page 1
6-15-00 Page 1
6-15-00 Page 1
6-20-00 Page 1
6-20-00 Page 1
6-20-00 Page 1
6-20-02
6-20-02
6-20-02
6-20-02

06 - CONTENTS

Page
Page
Page
Page

1
1
1
1

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
DIMENSIONS AND AREAS - GENERAL
1.

Scope
A.

B.
2.

This chapter includes illustrations and statistical information concerning the Model 172 airplane.
Provided are the overall airplane dimensions, surface areas, station locations, zones and access
plate locations.
Dimensions and measurements are presented to aid the operator and/or maintenance personnel in
ground handling the airplane and locating components.

Definition
A.

Airplane Dimensions and Areas.
(1) The section on airplane dimensions and areas provides airplane dimensions and identifies areas
of the airplane.

B.

Airplane Stations.
(1) The section on stations provides illustrations to identify reference points on the airplane along a
three axis division.

C.

Airplane Zoning.
(1) The section on zoning provides illustrations of all airplane zones.

D.

Access Plates/Panels.
(1) The section on access plates/panels provides numbering of all plates and panels based on
specific airplane zones.

6-00-00
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
AIRPLANE DIMENSIONS AND SPECIFICATIONS - DESCRIPTION AND OPERATION
1.

General
A.

Airplane dimensions and specifications have been compiled to serve as a central reference point for
airplane information. This information is presented in tabular and illustrative form below. Refer to
Figure 1 for an illustration of airplane dimensions.

AIRPLANE OVERALL
Length (Overall)

27' - 2"

Height (Maximum)

8' - 11"

Wing Span (Overall)

36' - 0"

Tail Span

11' -4"

Landing Gear Track Width

8' - 4 1/2"

FUSELAGE DIMENSIONS
Cabin Width (Maximum Sidewall to Sidewall)

3' - 3 1/2"

Cabin Height (Floorboard to Headliner)

4' - 0"

MAXIMUM WEIGHT
Ramp
172R

2457 Pounds

172S
(And 172R Airplanes Incorporating MK172-72-01)

2558 Pounds

Takeoff
172R

2450 Pounds

172S
(And 172R Airplanes Incorporating MK172-72-01)

2550 Pounds

Landing
172R

2450 Pounds

172S
(And 172R Airplanes Incorporating MK172-72-01)

2550 Pounds

FUEL CAPACITY
Total

56.0 Gallons

Usable

53.0 Gallons

ENGINE DATA
Type

Lycoming IO-360-L2A

Oil Capacity

8.0 Quarts

Oil Filter

CH48110

RPM (Maximum)
172R

2400 RPM

172S
(And 172R Airplanes Incorporating MK172-72-01)

2700 RPM

6-1 0-00
© Cessna Aircraft Company

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Apr 7/2003

CESSNA AIRCRAFT COMPANY

IVIODEL 172
MAINTENANCE MANUAL

Horsepower
172R

160 HP

172S
(And 172R Airplanes Incorporating MK172-72-01)

180 HP

PROPELLER
Type
172R

McCauley 1C235/LFA7570

172S
(And 172R Airplanes Incorporating MK172-72-01)

McCauley 1A170E/JHA7660

Diameter (Maximum to Minimum)
172R

75" - 74"

172S
(And 172R Airplanes Incorporating MK172-72-01)

76" - 75"

TIRE, STRUT AND WHEEL ALIGNMENT DATA
Main Tire Size
172R

6.00 X 6, 4-Ply Rating

172S
(And 172R Airplanes Incorporating MK172-72-01)

6.00 X 6, 6-Ply Rating

Main Tire Pressure
172R

28.0 PSI

172S
(And 172R Airplanes Incorporating MK172-72-01)

38.0 PSI

Nose Tire Size
172R, 172S

5.00 X 5, 6-Ply Rating

Nose Tire Pressure
172R

34.0 PSI

172S
(And 172R Airplanes Incorporating MK172-72-01)

45.0 PSI

Nose Gear Strut Pressure (Strut Extended)

45.0 PSI

Camber (Measured With Airplane Empty)

2 to 4 Degrees

Toe-In (Measured With Airplane Empty)

0.00 to 0.18"

CONTROL SURFACE TRAVELS/CABLE TENSION
SETTINGS
AILERONS
Aileron Up Travel

20 Degrees, ±1 Degree

Aileron Down Travel

15 Degrees, ±1 Degree

Aileron Cable Tension (Carry Through)

40 Pounds, ±10 Pounds

RUDDER

6-10-00
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Rudder Travel (Measured Parallel to Water Line)
Right

16 Degrees 10 Min; ±1 Degree

Left

16 Degrees 10 Min; ±1 Degree

Rudder Travel (Measured Perpendicular to Hinge Line)
Right

17 Degrees 44 Min; ±1 Degree

Left

17 Degrees 44 Min; ±1 Degree

ELEVATOR
Up Travel (Relative to Stabilizer)

28 Degrees, +1 or -0 Degree

Down Travel (Relative to Stabilizer)

23 Degrees, +1 or -0 Degree

Elevator Cable Tension

30 Pounds, ±10 Pounds

ELEVATOR TRIM TAB
Up Travel

22 Degrees, +1 or -0 Degree

Down Travel

19 Degrees, +1 or -0 Degree

Elevator Trim Cable Tension

20 Pounds, +0 or -5 Pounds

FLAPS
Flap Setting:
0 Degree (UP)

0 Degree

10 Degrees

10 Degrees, +0 or -2 Degrees

20 Degrees

20 Degrees, +0 or -2 Degrees

30 Degrees (FULL)

30 Degrees, +0 or -2 Degrees

Flap Cable Tension

30 Pounds, ±10 Pounds

6-10-00
© Cessna Aircraft Company

Page 3

Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1418

o0

00

.Oo

36' - 0"

J-

--

IS

PROPELLER DIAMETER
147

I /1

^

-13

"-'I

182S-76" (AND 172R AIRPLANES
INCORPORATING MK172-72-01)

.4[

27' - 2"

=d

A

.fi-

-.

/

'-11"

v
051OT 1005
051OT 1005
0510T 1005

Airplane Dimensions
Figure 1 (Sheet 1)

6-10-00
© Cessna Aircraft Company

Page 4

Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
AIRPLANE STATIONS - DESCRIPTION AND OPERATION
1.

General
A.

The airplane is laid out according to fuselage stations (FS) and wing stations (WS). These stations
provide fixed reference points for all components located on or within the airplane. Fuselage Stations
begin at the firewall (FS 0.00) and extend to the tailcone area (FS 230.18). Wing Stations begin at
the root (WS 23.62) and extend to the tip (WS 208.00). Both Fuselage Stations and Wing Stations
are measured in inches. For example, FS 185.50 is 185.50 inches aft of the firewall (FS 0.00).

B.

For an illustration of Fuselage Stations, refer to Figure 1. For an illustration of Wing Stations, refer to
Figure 2.

6-15-00
© Cessna Aircraft Company

Page 1

Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1643

FS 3.375

FS 142.00

FS 65.33
65.33

FS 108.00

FS 16.66
FS 0.00

I,

D

[

,I
\I
II

I
rI
I,

L,

j

I

V

II

II

FS 178.00

FS 228.68

FS 90.00

FS 8.12
FS 44.00

FS 80.00

FS 124.00

FS 56.70

0510T1008

Fuselage Stations
Figure 1 (Sheet 1)

6-15-00
© Cessna Aircraft Company

Page 2

Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1644

99 F7r; WC

23.65 W c

NS
).00 WS

100.00 WS

208.00 WS

208.00 WS

0522T3001

Wing Stations
Figure 2 (Sheet 1)

6-15-00
© Cessna Aircraft Company

Page 3

Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
AIRPLANE ZONING

-

DESCRIPTION AND OPERATION

General
A.

The Model 172 is divided into numbered zones to provide a method for locating components and/or
placards throughout the airplane. The zones are identified by a three-digit number as shown in the
example below. The first digit in the sequence denotes the major zone (300 series for aft of cabin,
500 series for left wing, etc.). The second digit in the sequence further divides the zone into submajor
zone (Zone 51 0 for inboard portion of the left wing and Zone 520 for outboard portion of the left wing,
etc..). The third digit further divides the submajor zones into subdivisions (if no subdivision is needed,
this digit is typically assigned as 0 (zero).

EXAMPLE
Major Zone

310
I I

Subdivision Zone

Submajor Zone

B.

2.

Major Zones.
(1) 100 - Forward side of firewall and forward.
(2) 200 - Aft side of firewall.
(3) 300 - Aft of cabin to end of airplane.
(4) 500 - Left wing.
(5) 600 - Right wing.
(6) 700 - Landing gear.

Description
A. For a breakdown of the airplane zones, refer to Figure 1.

6-20-00
© Cessna Aircraft Company

Page 1
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1645

110

120

210

310

720
340

110

211
(INTERIOR)

051 0T3001
051 0T3001
051 0T3001

Airplane Zones
Figure 1 (Sheet 1)

6-20-00
©Cessna Aircraft Company

Page 2
Jul 1/2007

0

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1646

INSTRUMENT PANEL

FIREWALL LOOKING FORWARD
0513T 1003
051 1T1002

Airplane Zones
Figure 1 (Sheet 2)

6-20-00
Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1647

INTERIOR FLOOR

051 1T1015

Airplane Zones
Figure 1 (Sheet 3)

6-20-00
© Cessna Aircrafl Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ACCESS/INSPECTION PLATES
1.

I

-

DESCRIPTION AND OPERATION

General
A.

There are access and inspection panels on the interior and exterior of the airplane. These panels give
access to components and airframe areas.
NOTE:

B.
2.

3.

Panels that have hinges attached to them (like the oil door for example) are not referred to
as panels and are not included in this section.
This section can be used in conjunction with inspection practices (Chapter 5) or standard maintenance
practices to quickly find related components throughout the airplane.

Access/inspection Panel Numbering
A.

All access/inspection panels have a series of numbers and letters which identify their zone location,
sequence, and orientation.
(1) Zone Location - Zone location is identified by the first three numbers of any panels. This threenumber sequence is specified in Airplane Zoning - Description and Operation.
(2) Sequence - The sequence is identified by alphabetical letters follow the three-number sequence.
The first panel is identified as "A," the second panel is identified. as "B", and so on.
(3) Orientation - The orientation for each panel is identified by one of four letters that come after
the sequence letter. The orientation letters are "T" for top, "B" for bottom, "L"for left, and "R"for
right.

B.

With
(1)
(2)
(3)

access panel 510AB as an example, the breakdown is as follows:
Zone Location = 51 0 (inboard portion of left wing)
Sequence A (the first panel within the zone)
Orientation B (located on the bottom of the zone).

Description
A. Access/Inspection Panels.

6-20-02
©Cessna Aircraft Company

Page 1
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1652

230AT

230BT

230FT

2300T

230EFT
230HT
230DT
230JT

230GT

230KT

230LT

230MT

230NT

230RT

230 PT
230QT

231 CT

231 AT

231 BT
231 DT

231 ET

231 FT

231 GT

231 HT

231 KT

231 JT

CABIN FLOORBOARD PANELS
051 OTi 01 1A

Cabin Floorboard Panels
Figure 1 (Sheet 1)

6-20-02
©Cessna Aircraft Company

Page 2
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

Table 1. Cabin Floorboard Panels
Panel

Equipment Located In Area (Refer to Figure 1)

230AT

Brake Line

230BT

Fuel Pump and Reservoir

2300T

Fuel Pump and Reservoir

2300T

Fuel Lines, Wire Bundle

230ET

Elevator Bellcrank, Fuel Lines

230FT

Fuel Selector, Elevator Bellcrank

230GT

Fuel Line

230HT

Fuel Line

230JT

Fuel Lines, Wire Bundles

230KT

Elevator Trim Tab Pulley, ADF Antenna

230LT

Fuel Lines

230MT

Fuel Lines

230NT

Fuel Lines

230PT

Wire Bundle. Brake Line

230QT

Rudder Cables, Elevator Cables, Elevator Trim Cables

230RT

Brake Line

231 AT

Main Landing Gear Bulkhead

231 BT

Rudder Cables, Elevator Cables, Elevator Trim Cables

231 CT

Main Landing Gear Bulkhead

231 DT

Rudder Cables, Elevator Cables, Elevator Trim Cables

231 ET

Rudder Cables, Elevator Cables, Elevator Trim Cables

231 FT

Transponder Antenna

231 GT

Rudder Cables, Elevator Cables, Elevator Trim Cables

231 HT

Structure

231 JT

Rudder Cables, Elevator Cables, Elevator Trim Cables

231 KT

Structure

6-20-02
©Cessna Aircraft Company

Page 3
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1 660

21 OAB

I21 OBB

320AB

2100CB

BOTTOM VIEW

LEFT VIEW

FUSELAGE PANELS
0522T1 019
051OT1024

Fuselage Panels
Figure 2 (Sheet 1)

6-20-02
©D
Cessna Aircraft Company

Page 4
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Table 2. Fuselage Panels
Panel

Equipment Located In Area (Refer to Figure 2)

120AT

External Power

21 OAB

Control Yoke/Elevator Attach

21 OBB

Brake Line, Rudder Cables, Elevator Cables, Elevator Trim Cables, Wiring

21 OCI3

Rudder Cables, Elevator Cables, Elevator Trim Cables

31 OAL

Elevator Pulleys, Elevator Trim Pulleys

31 OAR

Elevator Pulleys, Elevator Trim Pulleys

31 OBR

Rudder Cables, Elevator Cables, Elevator Trim Cables

320AB

Elevator Trim Actuator

6-20-02
Q Cessna Aircratt Company

Page 5
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1648

BOTTOM VIEW

WING ACCESS PANELS

0522T1 01 9

Wing Access Panels
Figure 3 (Sheet 1)

6-20-02
© Cessna Aircratt Company

Page 6
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1649

61 OCT

51 OCT

51 OBT

61 OBT
51 OAT

61 OAT

TOP VIEW

WING ACCESS PANELS

0510T1002

Wing Access Panels
Figure 3 (Sheet 2)

6-20-02
© Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Table 3. Wing Access Panels
Panel

Equipment Located In Area (Refer to Figure 3)

610OAB

Wiring

61 OBB

Wiring

6100CB

Strut Bolt

61 0DB

Fuel Lines, Fuel Transmitter

610OEB

Flap Controls

610OFB

Strut Bolt

61 0GB

Flap Actuator

610HB

Fuel Lines, Fuel Transmitter

610JB

Wing Structure

61 0KB

Wing Structure

610OLB

Flap Cables, Aileron Cables

61 0MB

Flap Cables, Aileron Cables

61ONB

Aileron Cables

620AB

Autopilot Roll Servo

620BB

Aileron Cables, Trim Cables

620CB

Aileron Cables

620DB

Aileron Bellcrank

620EB

Wing Structure

620FB

Wing Structure

620GB

Wing Structure

620HB

_Wing Structure

620JB

Wing Structure

51 OAB

Wiring

51 OBB

Wiring, Pitot Tube

510OCB

Strut Bolt

510DB

Fuel Lines, Fuel Transmitter

51lOEB

Flap Controls

51 OFB

Strut Bolt

51 0GB

Flap Actuator

51 OHB

Fuel Lines, Fuel Transmitter

510JB

Wing Structure, Courtesy Light

51 0KB

Wing Structure, Flap Bellcrank

510OLB

Flap Cables, Aileron Cables

6-20-02
© Cessna Aircrafl Company

Page 8
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
Table 3. Wing Access Panels (continued)
Panel
Equipment Located In Area (Refer to Figure 3)
51 0MB

Flap Cables, Aileron Cables

51 ONB

Aileron Cables

520AB

Aileron Cables, Trim Cables

520BB

Aileron Cables, Aileron Bellcrank

520CB

_Wing Structure

520DB

Wing Structure

520EB

Wing Structure

520FB

Wing Structure

520GB

Wing Structure

520HB

Magnetometer

61 OAT

Fuel Bay

61 OBT

Fuel Bay

61 OCT

Fuel Bay

51lOAT

Fuel Bay

51 OBT

Fuel Bay

51lOCT

Fuel Bay

6-20-02
© Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1651

51
(6'
51 1BT
(61 1BT)

511 CT (611 CT)
(61 1DT)

FLAP PANELS

0525T1 002

Flap Panels
Figure 4 (Sheet 1)

6-20-02
©Cessna Aircraft Company

Page 10
Jul 1/2007

CESSNA AIRCRAFT COMPANY

.MODEL 172
MAINTENANCE MANUAL

Table 4. Flap Panels
Panel

Equipment Located In Area (Refer to Figure 4)

51 1AT

Flap Access

511 BT

Flap Access

51liCT

Flap Access

511 DT

Flap Access

61 1AT

Flap Access

611 BT

Flap Access

611 CT

Flap Access

611 DT

Flap Access

6-20-02
© Cessna Aircraft Company

Page 11
Jul 1/2007

CHAPTER

LIFTING AND
SHORING

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

7-00-00

Page 1

Apr 7/2003

7-10-00

Pages 201-202

Apr 7/2003

7-11-00

Page 201

Apr 7/2003

07-Title
07-List of Effective Pages
07-Record of Temporary Revisions
07-Contents

07 - LIST OF EFFECTIVE PAGES
© Cessna Aircraft Company

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RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
LIFTING AND SHORING - GENERAL ....................

.........................

S cope......................................................................
Tools, Equipment and Material ...............................................
Definition ................................................. ................
JACKING - MAINTENANCE PRACTICES

........................................

General ....................................................................
Tools, Equipment and Materials ..............................................
Jacking Procedure ..........................................................

EMERGENCY LIFTING/HOISTING - MAINTENANCE PRACTICES ..................
Lifting Procedure ............................ ............................

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Page

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1
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201
201
201
201

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CONTENTS
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Page
Page
Page
Page

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
LIFTING AND SHORING - GENERAL
1.

Scope
A.

2.

This chapter describes both standard and emergency procedures used to lift the airplane off the
ground.

Tools, Equipment and Material
NOTE:

Equivalent substitutes may be used for the following listed items:

NAME

NUMBER

MANUFACTURER

USE

Jack

2-170

Cessna Aircraft Company
Cessna Parts Department
P.O. Box 949
Wichita, KS 67201

To jack wing.

Leg Extension

2-109

Cessna Aircraft Company

To extend legs on jack.

Slide Tube
Extension

2-70

Cessna Aircraft Company

To extend jack height.

Universal Tail
Stand

2-168

Cessna Aircraft Company

To secure tail.

Fabricate locally

To provide cushion
between wing jack and
wing spar.

Padded Block

3.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The section on Jacking provides normal procedures and techniques used to Jack the airplane off
the ground.
(2) The section on emergency lifting provides procedures, techniques and fabrication information
needed to lift the airplane by overhead means.

7-00-00
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
JACKING - MAINTENANCE PRACTICES
1.

General

CAUTION: JACKING BOTH WHEELS SIMULTANEOUSLY AT BUILT-IN JACK
PADS IS NOT RECOMMENDED. WHEN USING BUILT-IN JACK PAD,
FLEXIBILITY OF THE MAIN GEAR STRUT WILL CAUSE THE MAIN
WHEEL TO SLIDE INBOARD AS THE WHEEL IS RAISED, TILTING
THE JACK. IF THIS OCCURS, THE JACK MUST BE LOWERED FOR
A SECOND OPERATION.
A.

2.

Tools, Equipment and Materials
A.

3.

Normal Jacking procedures involve lifting one main wheel at a time. This procedure is best
accomplished using a floor jack in conjunction with the built-in jack pad (located directly below the
step on each strut).

For a list of required tools, equipment and materials, refer to Lifting and Shoring - General.

Jacking Procedure
NOTE:
A.

When the airplane needs to be raised off the ground at all points, the following procedure should
be used.

Raise Airplane (Refer to Figure 201).

CAUTION: WHEN PLACED ONJACKS,
NOSE
IS
AIRPLANE
THE
HEAVY.
TAIL STANDS MUST WEIGH ENOUGH TO KEEP THE TAIL
DOWN UNDER ALL CONDITIONS. ADDITIONALLY, THE
TAIL STAND MUST BE STRONG ENOUGH TO SUPPORT
ANY WEIGHT WHICH MIGHT BE TRANSFERRED TO THE
TAILCONE AREA DURING MAINTENANCE, CREATING A TAIL
HEAVY CONDITION.
(1)
(2)
(3)
B.

Carefully attach tail stand to tail tie-down ring.
Place wing jacks and padded blocks under front spar, just outboard of wing strut (Wing Station
118.00). Ensure that padded block (1 inch X 4 inch X 4 inch with 0.25 inch rubber pad) is resting
securely between spar and jack.
Raise wing jacks evenly until desired height is reached.

Lower Airplane (Refer to Figure 201).
(1) Slowly lower wing jacks simultaneously until main tires are resting on ground.
(2)
Remove wing jacks and pads from wing area.
Detach tail stand from tie-down ring.
(3)

7-1 0-00
© Cessna Aircraft Company

Page 201
Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1654

<1c

II,

05801001

Airplane Jacking
Figure 201 (Sheet 1)

7-10-00
© Cessna Aircraft Company

Page 202
Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
EMERGENCY LIFTING/HOISTING - MAINTENANCE PRACTICES
1.

Lifting Procedure
A.

The airplane may be lifted with a hoist of two-ton capacity attached by rings, which are optional
equipment installed by Service Kit, or by means of suitable slings. The front sling should be hooked
to each upper engine mount, and the aft sling should be positioned around the fuselage at the first
bulkhead forward of the leading edge of the stabilizer. If the optional hoisting rings are used, a
minimum cable length of 60 inches for each cable is required to prevent bending of the eyebolt-type
hoisting rings. If desired, a spreader jig may be fabricated to apply vertical force to the eyebolts.

7-11-00
© Cessna Aircraft Company

Page 201
Apr 7/2003

CHAPTER

LEVELING AND
WEIGHING

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

8-00-00

Page 1

Apr 7/2003

8-10-00

Pages 201-202

Jan 3/2005

08-Title
08-List of Effective Pages
08-Record of Temporary Revisions
08-Contents

08 - LIST OF EFFECTIVE PAGES
© Cessna Aircraft Company

Page 1 of 1
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RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
LEVELING AND WEIGHING - GENERAL ..........................................
Scope......................................................................

8-00-00 Page 1

Tools, Equipment and Material ...............................................
Definition...................................................................

8-00-00 Page 1
8-00-00 Page 1

LEVELING - MAINTENANCE PRACTICES.........................................

G en eral ....................................................................
Tools, Equipment and Materials ..............................................
Leveling Points .............................................................

8-00-00 Page 1
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CONTENTS
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Page
Page
Page
Page

201
201
201
201

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
LEVELING AND WEIGHING - GENERAL

1.

2.

Scope
A.

This chapter provides information necessary to properly level the airplane.

B.

For information on airplane weighing procedures, refer to the applicable Model 172 Pilot's Operating
Handbook and FAA Approved Airplane Flight Manual.

Tools, Equipment and Material

NAME

NUMBER

Spirit Level

3.

MANUFACTURER

USE

Commercially available

Spirit level used to level
airplane.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The section on leveling provides maintenance practices and instructions for longitudinal and
lateral leveling of the airplane. This leveling is accomplished using a spirit level of at least 18
inches in length.
(2) For information on weighing the airplane, refer to the applicable Model 172 Pilot's Operating
Handbook and FAA Approved Airplane Flight Manual.

© Cessna Aircraft Company

8-00-00
Page 1
Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
LEVELING - MAINTENANCE PRACTICES
1.

General
A.

2.

Tools, Equipment and Materials
A.

3.

This section gives reference points for leveling the airplane laterally and longitudinally.

For a list of required tools, equipment and materials, refer to Leveling and Weighing - General.

Leveling Points
A.

Lateral Leveling. (Refer to Figure 201).
(1) Find two points that are the same on each upper door sill of the left and right cabin doors.
(2) Put a level in position across these points.
NOTE:

Out-of-level tolerance for wing tips is three inches total.

(3) Make a note of the airplane's lateral position.
(4) If applicable, put jacks in position at the wings and tail jacking points. Refer to Jacking Maintenance Practices.
(a) Adjust the wing jacks as required to get the necessary lateral position.
B.

Longitudinal Leveling. (Refer to Figure 201).
(1) Find the two screws on the left side of the airplane tailcone that are in line with water line zero.
(2) Remove the screws.
(3) Install studs or long screws of applicable length (approximately two inches long).
(4) Put the level in position on the studs or screws.
(5) Make a note of the airplane's longitudinal position.
(6) If applicable, put jacks in position at the wings and tail jacking points. Refer to Jacking Maintenance Practices.
(a) Adjust the tail jack as required to get the necessary longitudinal position.

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MAINTENANCE MANUAL

B1655

REFERENCE POINTS
POINTS FOR
FOR THE
THE LEVELING
LEVELING PROCEDURE
PROCEDURE
REFERENCE

0510T3001

Airplane Leveling
Figure 201 (Sheet 1)

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CHAPTER

TOWING AND TAXIING

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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CONTENTS
TOWING AND TAXIING - GENERAL ..............................................

Scope......................................................................
Definition ...................................................................
TOWING - MAINTENANCE PRACTICES ..........................................

General ....................................................................

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MODEL 172
MAINTENANCE MANUAL
TOWING AND TAXIING - GENERAL
1.

Scope
A.

2.

This chapter describes towing procedures for movement of the airplane on the ground. For taxiing
procedures, refer to the applicable Pilots's Operating Handbook and FAA Approved Airplane Flight
Manual.

Definition
A.

The section on towing describes towing procedures and cautions applicable to the Model 172.

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MAINTENANCE MANUAL
TOWING - MAINTENANCE PRACTICES
1.

General

CAUTION: WHEN TOWING THE AIRPLANE, NEVER TURN THE NOSE
WHEEL MORE THAN 30 DEGREES EITHER SIDE OF CENTER,
OR THE GEAR WILL BE DAMAGED. DO NOT PUSH ON CONTROL
SURFACES OR ANY PORTION OF THE HORIZONTAL STABILIZER.
WHEN PUSHING ON THE TAILCONE, ALWAYS APPLY PRESSURE
AT A BULKHEAD TO AVOID DAMAGING THE SKIN.
A.

Towing.
(1) Moving the airplane by hand is accomplished by using the wing struts and landing gear struts as
push points. A tow bar attached to the nose gear should be used for steering and maneuvering
the airplane on the ground. When no tow bar is available, press down on the tailcone at a
bulkhead to raise the nose wheel off the ground. With the nose wheel clear of the ground, the
airplane can be turned by pivoting about the main wheels.

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MAINTENANCE MANUAL

WASHER
RH SIDEWALL
PANEL-AFT
BAGGAGE
SPACER

HOLDER

TOW BAR ASSEMBLY

DETAIL

A
0510T1007
A0714T1016

Tow Bar Installation
Figure 201 (Sheet 1)

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CHAPTER

PARKING AND
MOORING

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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PARKING, MOORING, STORAGE AND RETURN TO SERVICE - GENERAL .........
Sco pe......................................................................
Tools, Equipment and Materials ..............................................
Definition ...................................................................
PARKING - MAINTENANCE PRACTICES..........................................

General ....................................................................
Parking Instructions .........................................................

STORAGE - DESCRIPTION AND OPERATION ....................................
General ....................................................................
.....................
..............................
Flyable Storage .........
Temporary Storage..........................................................
Inspection During Storage ...................................................

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Temporary Storage Return to Service .........................................

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MODEL 172

MAINTENANCE MANUAL
PARKING, MOORING, STORAGE AND RETURN TO SERVICE - GENERAL
1.

Scope
A.

2.

This chapter describes and provides maintenance instructions for parking, storing, mooring and
returning the airplane to service.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes may be used for the following items:

NAME

NUMBER

MANUFACTURER

USE

Wheel Chocks

Available Commercially

To chock landing wheels.

Engine Air Inlet
Cover

Cessna Aircraft

To prevent entry of
moisture and/or foreign
particles through cowling.

Pitot Tube Cover

Cessna Aircraft

To prevent entry of
moisture and/or foreign
particles in pitot tubes.

Static Ground
Cable

Available Commercially

To static ground airplane.

Rope (0.375
inch diameter
minimum) or
equivalent

Available Commercially

To tie down wing and tail.

3.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The section on parking describes methods, procedures and precautions used when parking the
airplane.
(2) The section on storage provides information on recommended storage procedures.
Recommendations vary with the length of time the airplane is to be stored.
(3) The section on mooring describes procedures and equipment used to moor the airplane.
(4) The section on return to service describes procedures used when returning the airplane to
service from storage.

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MAINTENANCE MANUAL
PARKING - MAINTENANCE PRACTICES
1.

2.

General
A.

This maintenance practice covers procedures used to park the airplane.

B.

The airplane should be moored if high winds are anticipated or anytime the airplane remains outside
for extended periods of time. Refer to Mooring - Maintenance Practices for mooring procedures. Refer
to Storage - Maintenance Practices for detailed instructions regarding storage.

Parking Instructions
A.

Hard Surface and Sod.

CAUTION: ANY TIME THE AIRPLANE IS LOADED HEAVILY, THE
FOOTPRINT PRESSURE (PRESSURE OF THE AIRPLANE
WHEELS UPON THE CONTACT SURFACE OF THE PARKING
AREA OR RUNWAY) WILL BE EXTREMELY HIGH, AND
SURFACES SUCH AS HOT ASPHALT OR DAMP SOD MAY NOT
ADEQUATELY SUPPORT THE WEIGHT OF THE AIRPLANE.
PRECAUTIONS SHOULD BE TAKEN TO AVOID AIRPLANE
PARKING OR MOVEMENT ON SUCH SURFACES.
(1) Position airplane headed into wind, on level surface.

CAUTION: DO NOT SET PARKING BRAKE DURING COLD WEATHER,
WHEN ACCUMULATED MOISTURE MAY FREEZE BRAKES, OR
WHEN BRAKES ARE HOT.
(2) Set parking brake or chock main gear wheels.
(3) Install control column lock.

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MAINTENANCE MANUAL
STORAGE - DESCRIPTION AND OPERATION
1.

General
A.

As a result of corrosion, it is possible that some piston engines will not complete the usual service
life. Moisture from the air and material from combustion mix to cause corrosion on cylinder walls and
bearing surfaces when the engine is not in operation. A thin layer of corrosion inhibitor is used to help
prevent corrosion.
NOTE:

The owner or operator of the airplane must make a decision if preservation is necessary
as a result of environmental conditions and frequency of airplane use.

NOTE:
B.
C.

2.

Flyable Storage
A.

The flyable storage is a maximum of 30 days storage with no engine operation and/or the first 25
hours of intermittent engine operation.

B.

Engine temperature and length of operation time are very important in the control of corrosion. The
desired flight time for air cooled engines is at least one continuous hour at oil temperatures of 165
degrees F (74 degrees C) to 200 degrees F (93 degrees C) at intervals not to exceed 30 days. The
one hour does not include taxi, take-off and landing time.
The aircraft temperature gages must operate correctly.

C.
D.
E.

F.

G.
3.

The time periods given in this document are recommendations as given for normal
conditions.
In areas of high humidity, corrosion can start in a short period of time. Corrosion is found on cylinder
walls of new engines that have not operated for a period as short as two days.
In engines that have 50 hours or more time of service in a short period, the cylinder walls will have a
varnish that will help protect from corrosion. These engines in good atmospheric conditions can stay
inactive for many weeks without indication of corrosion.

The cooling air baffles must be in good condition and fitted properly.
The oil cooler system must be of the proper size for the engine and airframe installation. Oil coolers
that are not the correct size can cause an engine overheat condition or below minimum temperatures.
Low temperatures are as dangerous as high temperatures because of build-up of water and acids.
Pulling engines through by hand when the airplane is not operated for approximately a week is
not recommended. Pulling the engine through by hand before you start the engine or to minimize
corrosion can cause damage. The cylinder walls, pistons, rings, cam and cam follower receive
minimum lubrication. When the prop is pulled through by hand, the rings remove oil from the cylinder
walls. The cam load made by the valve train removes oil from the cam and followers. After two
or three times of pulling the engine through by hand without engine starts, the cylinders, cam and
followers are left without the correct quantity of oil film. Engine starts without the correct lubrication
can cause the engine parts to score which can cause damage to the engine.
The pitot tube, static air vents, air vents, openings in the engine cowl, and other openings must have
protective covers installed to prevent entry of foreign object debris.

Temporary Storage
A.

Temporary airplane storage.
(1) Temporary storage is when the airplane does not operate in a maximum of 90 days. The
airplane is made of corrosion resistant, epoxy primed aluminum, which will last a long time
in normal conditions. But these alloys can have oxidation. The first indication of corrosion
on surfaces without paint is white deposits or spots. Corrosion on surfaces with paint is
discoloration or blistered paint. Storage in a dry hangar is very important for good preservation.
Different conditions will change the measures of preservation, but for normal conditions in a
dry hangar, and for storage periods not to exceed 90 days, the procedures that follow are
recommended.

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WARNING: For procedures that require fuel, fire equipment must be
available. Two ground wires from different points on the

airplane connected to separate, approved ground stakes must
be used In case of accidental disconnection of one ground
wire. Make sure the fuel nozzle Is grounded to the airplane
(a)
(b)
(c)
(d)
(e)
(f)
(g)

Fill the fuel tanks with the correct grade of fuel.
Use tie-down rings for ground points for the fuel procedure.
Clean the airplane fully.
Clean oil or grease from the tires.
Put a thin layer of tire preservative on the tires.
Put a cover on the tires to keep grease and oil from the tires.
Keep the tires from deformation.
1
Put the fuselage on blocks to relieve pressure on the tires or rotate the wheels every
30 days to keep the tires from flat spots.
(h) Lubricate all airframe items.
(i) Put a cover on openings which let moisture and/or dust to enter.
B.

Temporary engine storage.
(1) If it is known that an aircraft is to be out of operation for 30 or more days, the procedures that
follow must be applied to the engine.
(a) Put a preservative in the engine by one of the methods that follow.
1
Drain the oil from the sump or system and replace with a preservative oil mixture.
This preservation mixture is one part by volume of MIL-C-6529C Type I concentrated
preservative compound added to three parts by volume of MIL-L-6082C (SAE J1966),
Grade 1100, mineral aircraft engine oil or oil that agrees to MIL-C-6529C Type II.
Carefully follow the manufacturer's instructions before use.
2
An alternative method is the use of Cortec VC1 -326 preservative concentrate added
to the original oil at a ratio of one part VC1-326 to ten parts of oil.
(b) Operate the engine to get the normal temperatures of operation.
1
Do not stop the engine until the oil temperature is 180 degrees F (82 degrees C). If
weather conditions are below 32 degrees F (0 degrees C), oil temperature must be
at least 165 degrees F (73 degrees C) before shutdown.
(c) Remove the engine cowl to get access to the top spark plugs.
(d) Remove the spark plugs.
NOTE:

Oils of the type given are to be used in Lycoming aircraft engines for preservation
only and not for lubrication.

(e) Through the spark plug hole, spray the interior of each cylinder with approximately two
ounces of the preservative oil mixture with an airless spray gun (Spraying Systems Co.,
Gunjet Model 24A-8395 or equivalent). If an airless spray gun is not available, a moisture
trap can be installed in the air line of a conventional spray gun.
(f) Install the spark plugs.
(g) Do not turn the crankshaft after the cylinders have been sprayed.
(h) If the aircraft is stored in a region of high humidity, or near a sea coast, it is better to
use dehydrator plugs and not the spark plugs. Cylinder dehydrator plugs, MS-27215-2 or
equivalent, can be used.
(i) Before the engine has cooled, install small bags of desiccant in the exhaust and intake
ports and seal with a moisture impervious material and pressure sensitive tape.
(j) Firmly attach red cloth streamers to any desiccant bags installed in the intake and exhaust
passages to make sure the material is removed when the engine is made ready for flight.
Streamers must be visible from outside the aircraft. Thr propeller must have a label that
says "Engine preserved - do not turn propeller".
(k) Seal all engine openings with plugs. Attach a red streamer at each point that a plug is
installed.

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MAINTENANCE MANUAL
If the airplane is to be stored outside, the pitot tube, static source vents, air vent openings
in the engine cowl, and other openings must have protective covers installed to prevent
entry of foreign object debris.
(m) Attach a warning placard to the propeller that says the propeller must not be moved while
the engine is in storage.
(n) At 15-day maximum intervals, a periodic check must be made of the cylinder dehydrator
plugs and desiccant. When the color of the desiccant has changed from blue to pink the
preservation procedure must be repeated.
(I)

WARNING: To prevent serious bodily Injury or death,

before the

propeller Is moved, obey all precautions to prevent the
engine start. Disconnect the spark plug leads. Make sure
the magnetos are switched off and P-leads are grounded.
Make sure the throttle Is closed and the mixture Is In Idle
cut-off. Do not stand within the arc of the blade. Even
without spark, compression can cause the propeller to
move with sufficient force to cause serious Injury.
C.

4.

Return the airplane to service.
(1) To return the airplane to service, remove seals, tape, and desiccant bags. Use solvent to remove
tape residue. Remove spark plugs or dehydrator plugs. With the magnetos off, turn the propeller
by hand through sufficient rotation to remove excess preservative oil from the cylinders. Drain
the remaining preservatives from the engine through the sump.
(2) Install spark plugs and reconnect all parts in accordance with manufacturer's instructions.
Service the engine with approved lubrication oil.

Inspection During Storage
A.

Do an inspection of the airplane.
(1) Do an inspection of the airframe for corrosion at least once a month and remove dust collection
as frequently as possible. Clean the airplane as required.
(2) Do an inspection of the interior of at least one cylinder through the spark plug hole for corrosion
at least once a month.
NOTE:

Do not move crankshaft when the interior of the cylinders is examined for corrosion.

(3) If at the end of the 90 day period, the airplane is to be continued in storage, repeat the 90-day
storage procedure.

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MODEL 172

MAINTENANCE MANUAL
MOORING - MAINTENANCE PRACTICES

1.

Mooring
A.

When mooring the airplane in the open, head into the wind if possible. Tie down the airplane as
follows:
(1) Secure control surfaces with the internal control lock and set brakes.
(2) Tie ropes, cables, or chains to the wing tie-down fittings, located at the upper end of each wing
strut. Secure the opposite ends of ropes, cables, or chains to ground anchors.
(3) Secure rope (no chains or cables) to forward mooring ring and secure opposite end to ground
anchor.
(4) Secure the middle of a rope to the tail tie-down ring. Pull each end of rope away at a 45 degree
angle and secure to ground anchors at each side of tail.
(5) Secure control lock on pilot control column. If control lock is not available, tie pilot control wheel
back with front seat belt.
(6) These airplanes are equipped with a spring-loaded steering system which affords protection
against normal wind gusts. However, if extremely high wind gusts are anticipated, additional
external locks may be installed.

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MAINTENANCE MANUAL
RETURN TO SERVICE - MAINTENANCE PRACTICES
1.

Flyable Storage Return to Service
A.

2.

Flyable storage is defined as a maximum of 30 days nonoperational storage and/or the first 25 hours of
intermittent engine operation. After flyable storage, returning the airplane to service is accomplished
by performing a thorough preflight inspection. At the end of the first 25 hours of engine operation,
drain engine oil and replace oil filter. Service engine with correct grade and quantity of engine oil.

Temporary Storage Return to Service
A.

Temporary storage is defined as airplane in a nonoperational status for a maximum of 90 days. After
temporary storage, use the following procedures to return the airplane to service:
(1) Remove airplane from blocks and check tires for proper inflation. Check for proper nose gear
strut inflation.
(2) Check battery and install.
(3) Check that oil sump has proper grade and quantity of engine oil.
(4) Service induction air filter and remove warning placard from propeller.
(5) Remove materials used to cover openings.
(6) Remove spark plugs from engine.
(7) While spark plugs are removed, rotate propeller several revolutions to clear excess oil from
cylinders.
(8) Clean, gap and install spark plugs. Torque spark plugs to the proper value and connect spark
plug leads.
(9) Check fuel strainer. Remove and clean filter screen if necessary. Check fuel tanks and fuel lines
for moisture and sediment. Drain enough fuel to eliminate any moisture and sediment.
(10) Perform a thorough preflight inspection, then start and warm up engine.

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CHAPTER

PLACARDS
AND
MARKINGS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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General ....................................................................

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PLACARDS AND MARKINGS - INSPECTION/CHECK ..............................
Scope......................................................................
Interior and Exterior Placard and Decal Inspection .............................

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PLACARDS AND MARKINGS - GENERAL..........

...........

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CONTENTS
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MODEL 172

MAINTENANCE MANUAL
PLACARDS AND MARKINGS - GENERAL
1.

General
A.

Placards and markings on the exterior surfaces of the airplane are found in the Model 172 Illustrated
Parts Catalog, Chapter 11.

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MAINTENANCE MANUAL
PLACARDS AND MARKINGS - INSPECTION/CHECK
1.

Scope
A.

2.

This section has inspection data for the interior and exterior placards.

Interior and Exterior Placard and Decal Inspection
NOTE:
A.

This section gives an inspection procedure for all placards, decals, and markings on the airplane.

Do an inspection of the placards, decals, and markings.
(1) Examine the interior of the airplane. Include the aft baggage areas for the installation of all
required placards, decals, and markings.
(a) For required placards, decals, and markings, refer to the Model 172R Illustrated Parts
Catalog.
(2) Examine the exterior of the airplane for the installation of all required placards, decals, and
markings.
(a) For required placards, decals, and markings, refer to the Model 172R Illustrated Parts
Catalog.
(3) Examine the airplane identification (ID) plate.
(a) The ID plate is found on the left side of the stinger, Zone 310. Refer to the Model 172R
Illustrated Parts Catalog and Chapter 6, Airplane Zoning - Description and Operation.

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CHAPTER

SERVICING

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MODEL 172

MAINTENANCE MANUAL

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CONTENTS
SERVICING - GENERAL .............................
Scope....................................
Definition ..................................
REPLENISHING - DESCRIPTION AND OPERATION ................
General...................................
Description .................................
Fuel Capacity Table .............................
Approved Fuel Table.............................
Engine Oil Capacity Table...........................
NOSE LANDING GEAR SHOCK STRUT - SERVICING ...............
General...................................
Shock Strut Servicing Procedures.......................
NOSE LANDING GEAR SHIMMY DAMPER - SERVICING..............
General...................................
Shimmy Damper Servicing (On Airplanes that do not have the Lord Shimmy
Damper) .................................
Shimmy Damper Servicing (On Airplanes with the Lord Shimmy Damper).....
HYDRAULIC BRAKES - SERVICING........................
General...................................
FUEL AND ENGINE OIL - DESCRIPTION AND OPERATION.............
General...................................
Fuel Precautions...............................
Oil Precautions ...............................
FUEL - SERVICING................................
General...................................
Safety and Maintenance Precautions .....................
Fueling and Defueling ............................
Aviation Fuel Additive ............................
Fuel Loading ................................
ENGINE OIL - SERVICING ............................
General...................................
Oil Change Intervals .............................
Engine Oil Level...............................
Engine Oil Change..............................

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INDUCTION AIR FILTER - SERVICING.......................
General ...................................
CA3559 Air Filter Service...........................
P1 98281 Air Filter Service ..........................

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VACUUM SYSTEM FILTERS - SERVICING.....................
General...................................
Gyro Filter Servicing .............................
Regulator Valve Filter Servicing........................
BATTERY - SERVICING..............................
General...................................
Battery Servicing...............................
TIRES - SERVICING ...............................
General...................................
Safety Precautions and Notes.........................
Tire Servicing ................................
Cold Weather Servicing............................

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© Cessna Aircraft Company

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MAINTENANCE MANUAL
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SCHEDULED SERVICING - DESCRIPTION AND OPERATION............
General...................................
Description .................................
LUBRICANTS - DESCRIPTION AND OPERATION .................
General...................................
Lubrication Service Notes...........................
Definition of "As Needed"............................
Recommended Lubricants Table .......................

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BATTERY TERMINALS - SERVICING .......................
General...................................
Battery Terminal Lubrication..........................

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LANDING GEAR AND PARKING BRAKE - SERVICING ...............
General...................................
Wheel Bearing Lubrication ..........................
Nose Gear Torque Link Lubrication ......................
Shimmy Dampener Pivots Lubrication.....................
Steering System Needle Bearing Lubrication..................
Nose Gear Steering Pushrods Lubrication ...................
Parking Brake Handle Shaft Lubrication ....................

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FLIGHT CONTROLS - SERVICING.........................
General...................................
Aileron System Lubrication ..........................
Flap System Lubrication ...........................
Elevator System Lubrication.
...................
......
Rudder System Lubrication..........................
ENGINE CONTROL CABLES - SERVICING ....................
General...................................
Engine Control Cables Lubrication.......................
HEATING AND VENTILATION CONTROL CABLES - SERVICING ..........
General. .................................
Heating And Ventilation Control Cables Lubrication ...............
AIRPLANE EXTERIOR - CLEANING/PAINTING...................
General...................................
Precautions.................................
Preventive Maintenance ...........................
Windshield and Window Cleaners.......................
Cleaning Windshield and Windows ......................
Waxing and Polishing Windshield and Windows ................
Aluminum Surfaces .............................
Painted External Surfaces ..........................
Engine and Engine Compartment Washing...................
Propeller ..................................
Tires and Wheels ..............................

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AIRPLANE INTERIOR - CLEANING/PAINTING ...................
General...................................
Interior Cleaning Materials ..........................
To Clean Interior Panels ...........................
To Clean Carpet...............................
To Clean Seats ...............................
To Clean the GDU 1040 Display Lens .....................

.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
EXTERIOR GRAPHICS - MAINTENANCE PRACTICES ...............
General...................................
Tools and Equipment.............................
Note 1: This product is for airplanes manufactured before June 2002 .......
Note 2: This product is for airplanes manufactured after June 2002........
Note 3: This product is for airplanes manufactured before January 2004......
Note 4: This product is for airplanes manufactured after January 2004 ......
Graphics Removal/Installation.........................
Exterior Graphics Preservation ........................
UNSCHEDULED SERVICING - DESCRIPTION AND OPERATION ..........
General...................................
Extreme Weather Maintenance ........................
Cold Soak..................................

©Cessna Aircraft Company

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1

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
SERVICING - GENERAL
1.

Scope
A.

2.

This chapter provides instructions for the replenishment of fluids, scheduled and unscheduled
servicing applicable to the entire airplane. Personnel shall observe safety precautions pertaining to
the individual servicing application.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief description of each
section follows.
(1) The section on replenishing is subdivided into categories to group servicing information such
as systems requiring hydraulic fluid or compressed gas. A brief description of the subdivision
subjects follows.
(a) Replenishing charts forthe liquids most commonly used to service the airplane are grouped
together to aid maintenance personnel in servicing.
(b) The subdivision of fuel and oil provides maintenance personnel with general servicing
procedures. Safety precautions and servicing procedures required by federal and local
regulations may supersede the procedures described.
(c) The subject on hydraulic fluid servicing provides servicing procedures for the airplane
hydraulic brake system, nose gear shimmy damper and nose gear strut.
(d) The remaining subject subdivisions provide service information on either a system, an
assembly or a component.
(2) The section on scheduled servicing includes lubrication information, external cleaning and
internal cleaning. The section is subdivided to provide individual system, assembly or
component service information.
(3) The section on unscheduled servicing provides information on deicing an airplane or portions of
an airplane.

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MODEL 172
MAINTENANCE MANUAL
REPLENISHING - DESCRIPTION AND OPERATION
1.

General
A.

2.

3.

This section provides maintenance personnel with servicing information for replenishing fuel and oil.

Description
A.

For an illustration of service points located on the airplane, refer to Figure 1. This illustration may be
used in conjunction with replenishing tables to aid maintenance technicians in servicing the airplane.

B.

The
(1)
(2)
(3)

following tables are provided to establish replenishment capacities of various systems:
Fuel Capacity (Table 1)
Approved Fuels (Table 2)
Engine Oil Capacity (Table 3)

Fuel Capacity Table
A.

The following table lists airplane fuel capacity.

WARNING: Only aviation grade fuels are approved for use.
Table 1. Fuel Capacity

U.S.
Fuel Capacity

56.0

Gallons
Usable Fuel

4.

53.0
Gallons

Approved Fuel Table
A.

The following table lists approved fuels for use in the airplane.

Table 2. Approved Fuels

TYPE OF FUEL

SPECIFICATION

COLOR

100 LL

ASTM-D910

Blue

100

ASTM-D910

Green

For other fuels that can be used in Russia, refer to Lycoming Service Instruction No. 1070M (or
subsequently approved Lycoming Service Instruction revision).
5.

Engine Oil Capacity Table
A.

The following table lists oil capacity for the airplane. For list of approved engine oil, refer to the Pilot's
Operating Handbook and FAA Approved Flight Manual.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

WARNING: The U.S. Environmental Protection Agency advises mechanics and
other workers who handle oil to minimize skin contact with used
oil and to promptly remove used oil from skin. In a laboratory
study, mice developed skin cancer after skin was exposed to used
engine oil twice a week without being washed off. Substances
found to cause cancer in laboratory animals may also cause cancer
in humans.
Table 3. Engine Oil Capacity

U.S. Quarts
Oil Capacity (total with filter, oil cooler and cooler
hoses)

8.0 quarts

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1668

T

A

k

11/

FUEL STRAINER-

INDUCTION AIRFILTER

STATIC PORT

NOSE LANDING
GEAR SHIMMY
DAMPER
NOSE LANDING
GEAR SHOCK
STRUT

PITOT

POWER JUNCTION BOX
AND GROUND SERVICE
RECEPTACLE
FUEL SELECTOR AND
FUEL RESERVOIR DRAINS
BRAKE MASTER
CYLINDERS

BATTERY

0510T1001

Airplane Service Points
Figure 1 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
NOSE LANDING GEAR SHOCK STRUT - SERVICING
1.

General
A.

2.

I

The nose gear shock strut requires a periodic check to make sure the strut is filled with hydraulic
fluid and is inflated to the correct air pressure. The procedures give only replenishing and servicing
instructions. For the disassembly and repair procedures, refer to Chapter 32, Nose Landing Gear Maintenance Practices.

Shock Strut Servicing Procedures
A.

The nose landing gear shock strut must be serviced every 100 hours.

B.

To service the nose gear shock strut, proceed as follows:
(1) Raise airplane nose to remove pressure from shock strut.
(2) Remove valve cap and release all air.
(3) Remove valve housing assembly.
(4) Compress strut completely (stops in contact with outer barrel hub).
(5) Check and replenish oil level.
NOTE:

Fluid used must comply with specification MIL-PRF-5606.

(a) Fill strut to bottom of valve installation hole.
(b) Maintain oil level at bottom of valve installation hole.
(6) Fully extend strut.
(7) Reinstall valve housing assembly.
(8) With strut fully extended and nose wheel clear of ground, inflate strut to 45 PSI.

I

NOTE:

The nose landing gear shock strut will normally require only a minimum amount of
service. Strut extension pressure must be maintained at 45 PSI. Machined surfaces
must be wiped free of dirt and dust using a clean, lint-free cloth saturated with MILPRF-5606 or kerosene. All surfaces must be wiped free of excessive hydraulic fluid.

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MAINTENANCE MANUAL
NOSE LANDING GEAR SHIMMY DAMPER - SERVICING
1.

General
A.

2.

3.

This procedure gives servicing instructions for the shimmy damper. To disassemble the shimmy
damper, refer to Chapter 32, Nose Gear - Maintenance Practices.

Shimmy Damper Servicing (On Airplanes that do not have the Lord Shimmy Damper)
A.

Service the shimmy damper every 100 hours.

B.

Service the shimmy damper as follows:
(1) Remove the shimmy damper from the airplane. Refer to Chapter 32, Nose Landing Gear Maintenance Practices.
(2) While you hold the damper in a vertical position with the fitting end pointed down, pull the fitting
end of the damper shaft to its limit of travel.
(3) While you hold the damper in this position, fill the damper through the open end of the cylinder
with hydraulic fluid.
(4) Push the shaft up slowly to seal off the filler hole.
(5) Clean the damper with solvent. Make sure that the shaft comes out through the filler hole until
the damper is installed on the aircraft.
(6) Install the damper on the airplane. Refer to Chapter 32, Nose Landing Gear - Maintenance
Practices.

C.

Keep the shimmy damper clean.
(1) Clean the shimmy damper with a clean, lint-free cloth to prevent the collection of dust and grit.
(2) Make sure that the part of the damper piston shaft that you can see is always clean.
(3) Clean the machined surfaces of the shimmy damper.
(a) Use a clean, lint-free cloth soaked with hydraulic fluid to clean the machined surfaces.
(b) After the surfaces are clean, remove the remaining hydraulic fluid from them with a clean,
lint-free cloth.

Shimmy Damper Servicing (On Airplanes with the Lord Shimmy Damper)
A.

Lord Shimmy Dampers do not need special servicing. However, you must lubricate the nose wheel
shimmy damper pivots with general purpose oil MIL-L-7870.

B.

Keep the shimmy damper clean.
(1) Clean the shimmy damper with a clean, lint-free cloth to prevent the collection of dust and grit.
(2) Make sure that the part of the damper piston shaft that you can see is always clean.
(3) Clean the machined surfaces of the shimmy damper with a clean, lint-free cloth to prevent the
collection of dust and dust.

C.

If necessary, exercise a shimmy damper before installation.
(1) If a shimmy damper has been in storage for a long period, make sure that it moves freely before
you install it.

CAUTION: Make sure that you do not push or pull on the shaft of the shimmy
damper after it has reached its limit in either the up or the down
position. If you continue to push a fully compressed, bottomedout shaft, you can cause damage to the shimmy damper. If you
continue to pull on a fully extended shaft, you can cause damage
to the shimmy damper.
(2)

If the shimmy damper does not move freely, push and pull the shaft through complete cycles
until it does move freely. When the shimmy damper shaft has come to its limit of travel up and
down as you push and pull, make sure that you do not continue to push or pull it beyond that
limit of travel.

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MODEL 172
MAINTENANCE MANUAL
HYDRAULIC BRAKES - SERVICING

1.

General
A.

The brake master cylinders must be serviced every 100 hours.

B.

The brake master cylinders are on the pilot's rudder pedals and are filled with MIL-PRF-5606 hydraulic
fluid.
NOTE:

For bleeding procedures, refer to Chapter 32, Brakes - Maintenance Practices.

(1) Remove the filler plug on the top of each master cylinder to fill the brake master cylinders.
(2) Fill to the top of the internal reservoir with MIL-PRF-5606 hydraulic fluid.

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MAINTENANCE MANUAL
FUEL AND ENGINE OIL - DESCRIPTION AND OPERATION
1.

General
A.

This section provides servicing procedures for the fuel and engine oil system. It is subdivided as
follows:

(1) The fuel system section includes procedures for adding fuel, defueling the airplane and mixing
anti-icing additives to the fuel.
(2) The engine oil section includes procedures for checking, adding and changing engine oil.
2.

3.

Fuel Precautions
A.

Safety Precautions.
(1) The safety precautions on fueling and defueling may be superseded by local directives.
However, following is a typical list of precautions.
(a) Ground, by designated grounding cables, the fueling and/or defueling vehicle to the
airplane. Also, a static ground device shall contact the fueling or defueling vehicle and
ground.
(b) Fire fighting equipment shall be immediately available.
(c) Wear proper clothing.
Do not wear clothing that has a tendency to generate static electricity such as nylon
1
or synthetic fabrics.
2
Do not wear metal taps on shoes when working in areas where fuel fumes may
accumulate at ground level.
(d) The airplane shall be in a designated fuel loading or unloading area.
(e) High wattage, pulse transmitting avionics equipment shall not be operated in the immediate
vicinity.

B.

Maintenance Precautions.
(1) Use designated equipment for fuel loading and unloading to prevent contamination.
(2) Use proper procedures when adding fuel inhibitors.
(3) Use specified type of fuel.

Oil Precautions
A.

Maintenance Precautions.
(1) Use proper servicing procedures; do not overfill, do not mix manufacturer's brands of oil.

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MODEL 172
MAINTENANCE MANUAL
FUEL - SERVICING
1.

General
A.

B.

Fuel Tanks.
(1) Each wing contains an integral fuel bay, located between the front and rear spars, extending
from WS 31.38 to WS 65.125. Fuel bays should be filled immediately after each flight to lessen
condensation in the tanks and lines. A fuel filler cap is located on top of each wing and provides
a fueling/defueling point for each fuel bay.
Fuel Drains.
(1) Fuel drains are located at various places on the underside of each integral fuel bay and
throughout the fuel system. These drains are utilized to collect fuel samples for analysis. This
sampling is accomplished by placing the fuel sample cup up to the drain valve, and depressing
the valve with rod protruding from the cup.
NOTE:

2.

For detailed description and maintenance practices related to the fuel system, refer
to Chapter 28, Fuel - General.

Safety and Maintenance Precautions
A.

Safety Precautions.

WARNING: During all fuel system servicing procedures, fire fighting
equipment must be available. Two ground wires from tiedown
rings on the airplane to approved ground stakes shall be used
to prevent accidental disconnection of one ground wire. Make
sure battery switch is turned off, unless otherwise specified.
Establish ground as follows:
(a) Ground airplane first.
(b) Ground vehicle (or hose cart) to the same ground as the airplane.
(c) Bond vehicle (or hose cart) to airplane.
(d) Bond refuel nozzle to airplane.
(2) Ensure fire fighting equipment is positioned and immediately available.
(3) Do not wear clothing that has a tendency to generate static electricity such as nylon or synthetic
fabrics.
(4) Do not wear metal taps on shoes.
(5) The airplane should be in a designated fuel loading/unloading area.
(6) High wattage, pulse transmitting avionics equipment shall not be operated in the vicinity of the
fueling/defueling operation.
Maintenance Precautions.
(1) Use designated equipment for fuel loading/unloading to prevent contamination.
(2) Due to the chemical composition of anti-ice additive, improper blending of fuel and anti-icing
additive may cause the deterioration of the integral fuel tanks interior finish, thus promoting
corrosion. It is very important that the proper anti-ice additive blending procedures be followed.
(3) Use authorized type of fuel and anti-ice additive.
(4) During defueling, ensure anti-ice additive blended fuel and unblended fuel are not mixed.
(1)

B.

3.

Fueling and Defueling
A.

Fueling Procedures.

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CAUTION: Make sure that the correct grade and type of fuel is used to
service the airplane. Refer to Pilot's Operating Handbook and FAA
Approved Airplane Flight Manual for a list of approved fuels.
(1)
(2)
(3)
(4)
(5)
(6)
B.

4.

5.

Ground airplane and vehicle as outlined above.
Ensure battery switch is turned OFF.
Place protective mat around fuel filler area and remove fuel filler caps.
Fuel airplane. Ensure correct grade of aviation fuel is used.
Replace filler caps. Wipe up excess fuel from wing area.
Remove grounding equipment.

Defueling Procedures.
(1) Ground airplane and vehicle as outlined above.
(2) Ensure battery switch is turned OFF.
(3) Remove fuel filler caps.
(4) Insert defueling nozzle into fuel bay and begin defueling.
(5) Remove as much fuel as possible with defueling nozzle.
(6) Drain fuel from drains located on underside of fuselage.
(7) Remove drain valves from bottom of fuel tank and drain remaining fuel.
(8) Remove grounding equipment.

Aviation Fuel Additive
A.

When servicing fuel with anti-icing additive containing diethylene glycol monomethyl ether (DiEGME),
remember that it is harmful if inhaled, swallowed or absorbed through the skin, and will cause eye
irritation. Also, it is combustible. Before using this material, refer to all safety information on the
container.

B.

In cases of acute exposure, DiEGME is an eye and mucous membrane irritant, a nephrotoxin and
central nervous system depressant. It is toxic by skin absorption. Inhalation may cause irritation
to mucous membranes, although, due to it's low volatility this is not an extreme hazard at room
temperature or below. If DiEGME contacts the eye, it may cause pain and transient injury. It is
absorbed through the skin in toxic amounts.

C.

In the event DiEGME contact is experienced, the following emergency and first aid procedures should
be used.
(1) If ingested (swallowed), drink large quantities of water. Then induce vomiting by placing a finger
far back into the throat. Contact a physician immediately. If vomiting cannot be induced, take
victim immediately to the hospital or a physician. If victim is unconscious or in convulsions, take
victim immediately to the hospital or a physician. Do not induce vomiting or give anything by
mouth to an unconscious person.
(2) If eye or skin contact is experienced, flush with plenty of water (use soap and water for skin) for at
least 15 minutes while removing contaminated clothing and shoes. Call a physician. Thoroughly
wash contaminated clothing and shoes before reuse.

Fuel Loading

CAUTION: Make sure that the correct grade and type of fuel is used to service
the airplane. Refer to Pilot's Operating Handbook and FAA Approved
Airplane Flight Manual for a list of approved fuels.
A.

Approved fuel for the Model 172 airplane may or may not contain an anti-ice additive. The additive
incorporates a biocidal chemical which inhibits growth of fungal and bacterial organisms in fuel storage
reservoirs. Mixing anti-ice additive and fuel during refueling involves the utilization of an aerosol or
proportioned dispenser.

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MAINTENANCE MANUAL
B.

Mixing Icing Inhibitor Procedures.
NOTE:

Equivalent procedures may be substituted.

(1) When using aerosol cans, utilize the following procedures.
(a) Insert the fueling nozzle and fuel additive nozzle into the fuel filler.

WARNING: Anti-icing additives containing DiEGME are harmful if
inhaled, swallowed or absorbed through the skin and will
cause eye irritation.
CAUTION: Ensure that additive is directed into flowing fuel stream and
additive flow is started after fuel flow starts and is stopped
before fuel flow stops. Do not allow concentrated additive to
contact coated interior of fuel tank or airplane painted surface.
(b) Start refueling; then, direct the fuel additive into the fuel stream so as to blend the additive
simultaneously with the fuel as it fills the tank. The additive concentration range shall be
maintained in accordance with instructions in the Pilot's Operating Handbook and FAA
Approved Airplane Flight Manual.

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MAINTENANCE MANUAL
ENGINE OIL - SERVICING

1.

General
A.

2.

This section gives instructions to examine and replace the engine oil.

Oil Change Intervals
A.

Oil Change Intervals.
NOTE:

An inspection of the oil filter will help find unusual engine wear. Refer to the Lycoming
Service Bulletin 480D or the latest revision.

(1) You must frequently do a check of the oil during the first 25 hours of engine operation and add
oil as necessary. Use an aviation grade mineral oil of the required viscosity which agrees with
SAE J1966. Refer to Engine Oil Check.
(2) After the first 25 hours, drain the engine oil and replace the oil filter. Fill the engine through the oil
filler tube with aviation grade mineral oil of the required viscosity which agrees with SAE J1966.
Refer to Engine Oil Change.
(3) Continue to use the aviation grade mineral oil until the airplane completes a total of 50 hours of
engine operation or oil consumption is stabilized. You must then drain the engine oil, replace
the oil filter and add ashless dispersant oil to the engine. Refer to Engine Oil Change.
(4) For more information on engine oil replacement intervals, refer to Chapter 5, Inspection Time
Limits.
3.

Engine Oil Level
A.

Engine Oil Check (Refer to Figure 301).
(1) Make sure the airplane is in a level position for the best indication.
(2) Wait five to ten minutes after the engine has stopped, then examine the engine oil level on the
dipstick.
(a) Open engine oil door on the top cowl.
(b) Remove the dipstick from the engine.
(c) Wipe the dipstick with a clean cloth.
(d) Fully insert the dip stick into the oil filler tube and remove the dipstick.
(e) Read oil level on dipstick.

CAUTION: THE AIRPLANE CAN OPERATE WITH SAE J1966 STRAIGHT
MINERAL OIL DURING THE INITIAL BREAK-IN PERIOD OR
AFTER AN OVERHAUL. AFTER THE BREAK-IN PERIOD, USE
AN ASHLESS DISPERSANT OIL THAT AGREES WITH SAE
J1899. MAKE SURE YOU USE THE CORRECT OIL TYPE WHEN
YOU SERVICE THE ENGINE.
(3) If the oil is low, add the correct quantity and viscosity of aviation grade engine oil. Refer to
Replenishing - Description and Operation.
(4) Insert the dipstick into the oil filler tube.
(5) Do a check for the correct fit of the dipstick to make sure it is not loose.
(6) Close engine oil door.
4.

Engine Oil Change
A.

Change the Engine Oil (Refer to Figure 301).
(1) Operate engine until oil temperature is at a normal operating temperature.
NOTE:

Normal temperature operation is within the green arc of the oil temperature gage.
The engine oil must drain while the engine is still warm.

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MAINTENANCE MANUAL

^

4 PA

OIL FILLER
TUBE

OIL
FILTER

;

I

DETAIL

I

)

A

0510T1007
A0556T1008

Engine Oil Service
Figure 301 (Sheet 1)

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MAINTENANCE MANUAL
WARNING: AVOID SKIN CONTACT WITH ENGINE OIL. ENGINE OIL THAT
GETS ON THE SKIN MUST BE IMMEDIATELY REMOVED.
(2) Shut off the engine.
(3) The front of the airplane must be raised slightly to drain sludge that can collect in the engine oil
sump.
(4) Remove the top cowl to get access to the oil drain plug and external oil filter. Refer to Chapter
71, Cowl - Maintenance Practices.
(5) Put a cover such as a plastic bag over the lower vacuum pump when you replace the oil or oil
filter to prevent contamination of the vacuum pump.
(6) Remove and discard the safety-wire from the drain plug.

WARNING: YOU MUST PREVENT SKIN CONTACT WITH ENGINE OIL. ANY
ENGINE OIL THAT GETS ON THE SKIN MUST BE REMOVED
IMMEDIATELY.
(7) Remove the drain plug and let the oil drain into an applicable container.
(8) After the engine oil has drained, install the drain plug. Refer to the Lycoming SSP-1776 Table
of Limits or latest revision, for the torque requirements.
(9) Attach safety-wire to the drain plug. Refer to Chapter 20, Safetying - Maintenance Practices.
(10) Remove suction screen from oil sump.
(a) Complete an inspection for metal particles.
1
If you see metal content, keep the material from the oil sump for identification.
Additional investigation will be required to find the source of the metal and possible
need for corrective maintenance. Refer to Lycoming SSP500 (or latest revision) and
contact a Textron Lycoming representative.
(b) Install the suction screen with a new gasket. Refer to the Lycoming SSP-1776 Table of
Limits (or latest revision) for torque requirements.
(c) Attach safety-wire to the suction screen. Refer to Chapter 20, Safetying - Maintenance
Practices.
(11) Remove the external oil filter.
(a) Open the filter can and examine the oil from the filter for metal particles.
(b) Carefully remove and unfold the paper element. Do an inspection of the material in the
filter.
1
If metal content is shown, keep the material from the filter for identification. Additional
investigation will be required to find the source of the metal and possible need for
corrective maintenance. Refer to Lycoming SSP500 and contact a Textron Lycoming
representative.
(c) Install a new external oil filter.
(d) Attach safety-wire to the oil filter. Refer to Chapter 20, Safetying - Maintenance Practices.
(12) Fill the engine oil sump through the filler tube. Make sure you use the correct grade and quantity
of oil. Refer to Replenishing - Description and Operation. Refer to Figure 302 for oil grade
versus temperature chart.
(13) Install the dipstick and make sure of the correct fit on the filler tube.
(14) Remove the bag from the lower vacuum pump.
(15) Operate the engine until the normal operating temperature shows on the oil temperature
indicator.
(16) Shutdown the engine.
(17) Examine the engine for oil leaks.

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MODEL 172
MAINTENANCE MANUAL

B1669

SPECIFIED AVIATION GRADE OIL:
AVERAGE AMBIENT TEMPERATURE (°F)/OIL GRADE
0°

10° 20°

30° 40° 50°

60°

70° 80°

90°

MAXIMUM OIL
TEMPERATURE
°F

SAE 60
SAE 40 or SAE 50

SAE 40

245°
245°

SAE 30, SAE 40 or SAE 20W-40
SAE 30 or
SAE 20W-30

245°

245°

SAE 15W-50 or SAE 20W-50

I

245°

245°

0598T1001

Temperature Versus Oil Viscosity
Figure 302 (Sheet 1)

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MODEL 172

MAINTENANCE MANUAL
INDUCTION AIR FILTER - SERVICING

1.

General
A.

2.

The induction air filter helps make sure dust and dirt does not go into the induction system.

CA3559 Air Filter Service
A.

CA3559 Air Filter (Refer to Figure 301).
(1) The CA3559 Induction Air Filter must be serviced at 50 hours, is life limited and must be replaced
at 100 hours. Refer to Chapter 5, Component Time Limits.

B.

Clean the CA3559 Air Filter (Refer to Figure 301).
(1) Remove the filter from the airplane.
(2) Replace the filter if it is damaged or split.
(3) If the filter is in serviceable condition, proceed with the steps that follow.
CAUTION: DO NOT USE MORE THAN 100 PSI COMPRESSED AIR TO
CLEAN THE FILTER . USE CARE NOT TO CAUSE DAMAGE
TO THE FILTER WHEN YOU CLEAN IT.
(a) Clean the filter from the opposite direction of the normal air flow with oil-free compressed
air that is less than 100 psi.
(b) Make sure the air box is clean and free of debris before you install the filter.
(c) Install the filter.

3.

P198281 Air Filter Service
A.

P198281 Air Filter (Refer to Figure 301).
(1) The filter must be serviced at 50 hours, is life-limited and must be replaced at 500 hours. A new
filter must be installed after using 500 hours of engine operating time or one year, whichever
occurs first. Refer to Chapter 5, Component Time Limits.

B.

Clean the P198281 Air Filter (Refer to Figure 301).
NOTE:

The filter assembly can be cleaned with compressed air a maximum of 30 times or it can
be washed a maximum of 20 times. Refer to the maintenance log book for a record of air
filter service.

(1) Remove the filter from the airplane.

CAUTION: DO NOT CLEAN THE FILTER WITH COMPRESSED AIR T-IAT IS
MORE THAN 100 PSI OR THE FILTER CAN BE DAMAGED.
(2) Clean the filter with oil-free compressed air that is less than 100 psi, from the opposite direction
of the normal air flow.
NOTE:

Arrows on the filter case show the direction of the normal air flow.

(3) Examine the paper pleats bond to the face screen.
(a) A new filter must be installed when the current filter is damaged. A damaged filter can
have sharp or broken edges in the filtering panels, which will let unfiltered air to enter the
induction system. Any filter that appears doubtful must have a new filter installed.
(b) Replace the filter if the face screen is loose or pulled away from the filter pleats. The bond
holds the paper pleats in place. If the bond is broken the pleats are free to move, which
will decrease filtration.

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MAINTENANCE MANUAL
B1569

A

BOTTOM COWL

DETAIL

A

0510T1007
A0550T1002

Air Filter Service
Figure 301 (Sheet 1)

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MAINTENANCE MANUAL

CAUTION: DO NOT USE SOLVENT OR CLEANING FLUIDS TO CLEAN THE
FILTER. USE ONLY WATER AND HOUSEHOLD DETERGENT
SOLUTION WHEN YOU WASH THE FILTER.
(4) After you clean the filter with air, the filter can be washed in a mixture of warm water and a mild
household detergent. A cold water mixture is acceptable.
(5) After you wash the filter, rinse it with clean water until the rinse water that drains from the filter
is clear.
(6) Let the water drain from the filter and dry with compressed air that is less than 100 psi.
NOTE:

The filtering panels of the filter can twist when they are wet, but they will return to
their original shape when they are dry.

When the filter is dry, exam it to make sure the filter is not damaged. If it is damaged, anew filter
must be installed.
(8) Make sure the air box is clean.
(9) Install the filter with the gasket on the aft face of the filter frame and with the flow arrows on the
filter frame pointed in the correct (normal air flow) direction.
(10) Make sure you update the maintenance log book to show the number of times the air filter has
been cleaned for future reference.
(7)

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MODEL 172

MAINTENANCE MANUAL
VACUUM SYSTEM FILTERS - SERVICING

1.

2.

General
A.

The vacuum system has two filters for which servicing is necessary. The gyro filter is forward of the
instrument panel on the pilot's side. The regulator valve filter is forward of the instrument panel near
the firewall centerline.

B.

An inspection of the gyro filter and the regulator valve filter must be done every 100 hours. Both filters
must be replaced at life limits set in Chapter 5, Component Time Limits.

Gyro Filter Servicing
A.

Servicing Procedures (Refer to Figure 301).

CAUTION: Do not operate the vacuum system with the filter removed or with
a vacuum line disconnected. Foreign object debris can go Into the

system and cause damage to the vacuum-operated Instruments.
(1) Remove the bolt and washer that attach the filter to the cover.
(2)
(3)
(4)
3.

Do an inspection of the filter for deterioration or damage.
Clean or, if applicable, replace the filter.
Install the filter in the cover and attach with the bolt and washer.

Regulator Valve Filter Servicing
A.

Servicing Procedure (Refer to Figure 301).

CAUTION: Do not operate the vacuum system with the filter removed or with
a vacuum line disconnected. Foreign object debris can go Into the
system and cause damage to the vacuum operated Instruments.
(1) Do an inspection of the filter for deterioration or damage.
(2)
(3)
(4)
(5)

If the filter is dirty, carefully remove it from the regulator valve.
Use shop air to clean the filter.
Replace damaged filter, if applicable.
Install the filter on the regulator valve.

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MODEL 172
MAINTENANCE MANUAL

INSTRUMENT
PANEL

REGULATOF
VALVE (WITI
FILTER)
I

FIREWALL

DIRECTIONAL
GYRO

FIREWALL

GYRO
FILTER

DETAIL A
0510T1007
A0518T1052

Vacuum System Filters
Figure 301 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B3829

VACUUM
TRANSDUCER

REPLACEMENT
FILTER

I

VACUUM
PUMP

v

-o

GYRO FILTER

DETAIL

B

AIRPLANES WITH GARMIN G1000
0510T1007
B0518T1105

Vacuum System Filters
Figure 301 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL -172

MAINTENANCE MANUAL
BATTERY - SERVICING
1.

General
A.

2.

This procedure provides instructions for adding water to the battery. For testing, charging and
maintenance on the battery, refer to Chapter 24, Battery - Maintenance Practices.

Battery Servicing
A.

The battery should be serviced every 100 hours.

B.

Battery servicing involves adding distilled water to maintain the electrolyte even with the horizontal
baffle plate at the bottom of the filler holes, checking the battery cable connections, and neutralizing
and cleaning off any spilled electrolyte or corrosion. Use bicarbonate of soda (baking soda) and water
to neutralize electrolyte or corrosion. Follow with a thorough flushing with a wire brush, then coat
with petroleum jelly before connecting. The battery box should also be checked and cleaned if any
corrosion is noted. Distilled water, not acid or "re-juvenators" should be used to maintain electrolyte
level. Inspect the battery in accordance with time limits spelled out in Chapter 5, Inspection Time
Limits.

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MODEL 172
MAINTENANCE MANUAL
TIRES

-

SERVICING

1.General
A. Servicing the tires by maintaining correct inflation pressure is the most important job in any tire
preventative maintenance program. Improper inflation pressure causes uneven tread wear.
(1) Under inflation, indicated by excessive wear in the shoulder area, is particularly damaging. It
increases the chance of bruising sidewalls and shoulders against rim flanges. In addition, it
shortens tire life by permitting excessive heat buildup.
(2) Over inflation is indicated by excessive wear in the center of the tire. This condition reduces
traction, increases tire growth and makes treads more susceptible to cutting.
2.

Safety Precautions and Notes
A. Safety Precautions.
(1) Tire should be allowed to cool before attempting to service.

WARNING: Do not stand in front of the bead area. The tendency of a
bursting tire is to rupture along the bead. Standing in any
position in front of either bead area could cause injury if the
tire should burst.
(2) Personnel should stand at a 90-degree angle to the axle along the centerline of the tire during
servicing.

CAUTION: Applying a tire sealant to the tire may cause wheel corrosion.
B.

3.

(3) The use of tire sealant is not recommended.
Notes.
(1) A tube-type tire that has been freshly mounted and installed should be closely monitored during
the first week of operation, ideally before every takeoff. Air trapped between the tire and the
tube at the time of mounting could seep out under the bead, through sidewall vents or around
the valve stem, resulting in an under inflated assembly.
(2) The initial stretch or growth of a tire results in a pressure drop after mounting. Consequently, tires
should not be placed in service until the have been inflated a minimum of 12 hours, pressures
rechecked, and tires reinflated if necessary.
(3) Inaccurate tire pressure gages are a major cause of improper inflation pressures. Ensure gages
used are accurate.

Tire Servicing
A. Check tire pressure regularly.
(1) Tire pressure should be checked when tire is cold (at least 2 or 3 hours after flight) on a regular
basis. Tire pressure should be checked prior to each flight when practical.
(2) When checking tire pressure, examine tires for wear, cuts, and bruises. Remove oil, grease and
mud from tires with soap and water.
B. Use recommended tire pressure. Consult the table below.
NOTE:

Recommended tire pressures should be maintained, especially in cold weather. Any drop
in temperature of the air inside a tire causes a corresponding drop in air pressure.

Main Gear Tire Type
I

Pressure

MODEL 172R
6.00 x 6, 4-ply rated tire

6.00 x 6, 6-ply rated tire

29 PSI

42 PSI

MODEL 172S

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MODEL 172

MAINTENANCE MANUAL

Nose Gear Tire Type
Pressure
4.

MODEL 172R

MODEL 172S

5.00 x 5, 6-ply rated tire

5.00 x 5, 6-ply rated tire

34 PSI

45 PSI

Cold Weather Servicing
A.

Cold Weather Servicing.
(1) Check tires for excessive deflation.
NOTE:

Tire air pressure will decrease somewhat as the temperature drops, but excessive
deflation could indicate cold weather leakage at the air valve. Avoid unnecessary
pressure checks.

(2) If it is necessary to pressure check tires in cold climates, always apply heat to air valves and
surrounding areas before unseating valves.
(3) Continue application of heat during reinflation to ensure air valve seal flexibility when valve
closes.
(4) Do not allow tires to stand in snow soaked with fuel, or on fuel covered ramp areas.
(5) If tires become frozen to parking ramp, use hot air or water to melt ice bond before attempting
to move airplane.

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MODEL -172
MAINTENANCE MANUAL
SCHEDULED SERVICING - DESCRIPTION AND OPERATION
1.

General
A.

2.

This section provides instructions necessary to carry out scheduled servicing as well as
internal/external cleaning. It also includes instructions for lubricating specific points identified
in periodic inspection and/or preventive maintenance programs. This section does not include
lubrication procedures required for the accomplishment of maintenance practices.

Description
A.

This section is subdivided to provide maintenance personnel with charts, text and illustrations to
prevent confusion. Also included in this section is a table containing a list of lubricants.
(1) The subdivisions are separated according to airplane systems. This aids maintenance personnel
in locating service information.

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MODEL 172
MAINTENANCE MANUAL
LUBRICANTS - DESCRIPTION AND OPERATION
1.

2.

General
A.

This section is designed to assist the operator in selecting recommended lubricants. For best results
and continued trouble free service, use clean and approved lubricants.

B.

For a list of recommended lubricants, refer to Recommended Lubricants Table.

Lubrication Service Notes
A.

3.

4.

Lubricant Application.
(1) Cleanliness is essential to good lubrication. Lubricants and dispensing equipment must be kept
clean. Use only one lubricant in a grease gun or oil can.
(2) Store lubricants in a protected area. Containers should be closed at all times when not in use.
(3) Wipe grease fittings and areas to be lubricated with clean, dry cloths before lubricating.
(4) When lubricating bearings which are vented, force grease into fitting until old grease is extruded.
(5) After any lubrication, clean excess lubricant from all but actual working parts.
(6) All sealed or prepacked antifriction bearings are lubricated with grease by the manufacturer and
require no further lubrication.
(7) Friction bearings of the porous, sintered type are prelubricated. An occasional squirt can oiling
of such bearings with general purpose oil (MIL-PRF-7870) extends its service life.
(8) Lubricate unsealed pulley bearings, rod ends, pivot end hinge points and any other friction point
obviously needing lubrication, with general purpose oil (MIL-L- 7870).
(9) Paraffin wax rubbed on seat rails will ease sliding the seats fore and aft.
(10) Do not lubricate roller chains or cables except under sea coast conditions. Wipe with a clean,
dry cloth.
(11) All piano hinges may be lubricated using (PG) powdered graphite (SS-G-659) when assembly
is installed.
(12) Lubricate door latching mechanism with MIL-PRF-81322 general purpose grease, applied
sparingly to friction points, if binding occurs. No lubrication is recommended on the rotary
clutch.

Definition of "As Needed"
A.

In the following sections, time requirements for lubrication are presented in one of two formats. When
specific time intervals for lubrication exist, those intervals are defined in Chapter 5, Inspection Time
Limits. When no time limit has been established, lubrication is on an "as needed" basis. This leaves
much of the decision making process in the hands of the airframe and powerplant mechanic, who has
been trained to make these types of decisions.

B.

In an effort to standardize the decision making process, the following guidelines may be considered
to determine if a component needs lubrication. Any one of the following conditions would indicate a
need for lubrication, and may additionally indicate the need for inspection:
(1) A visual inspection which indicates dirt or wear residue near the movement contact area.
(2) An audible inspection which indicates squeaks, grinding or other abnormal sounds.
(3) A tactile (touch and feel) inspection which indicates jerky or restricted movement throughout
portions of the travel range.

Recommended Lubricants Table
NOTE:

Equivalent substitutes may be used for the following items:

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Jan 2/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Table 1. Recommended Lubricants
SYMBOL

PROCUREMENT
SPECIFICATION

LUBRICANT
DESCRIPTION

PRODUCT
PART
NUMBER

SUPPLIER

GR

MIL-PRF-81322

Grease, wide
temperature
range.

Mobilgrease 28

Mobil Oil Corp.
150 E. 42nd Street
New York, NY 10017

Royco 22C

Royal Lubricants Co., Inc.
River Road
East Hanover, NJ 07936

Aeroshell
grease 22

Shell Oil Co.
One Shell Plaza
Houston, TX 77001

Southwest
Grease
16215

Southwest Petro- Chem,
Inc.
Division - Witco
1400 S. Harrison
Olathe, KS 66061

Aeroshell
grease 7

Shell Oil Co.

Royco 27A

Royal Lubricants Co., Inc.

Supermil
grease No.
A72832

Amoco Oil Co.
200 East Randolph Dr.
Chicago, IL 60601

Braycote
6275

Burmah-Castrol, Inc.
Bray Products Div.
16815 Von Karman Ave.
Irving, CA 92714

Castrolease A1

Burmah-Castrol, Inc.

TG-11900
low temp
grease EP

Southwest PetroChem,lnc.

Brayco 885

Brumah-Castrol, Inc.

GH

MIL-PRF-23827

Grease, aircraft
and instrument,
gear and
actuator screw.

OG

MIL-PRF-7870

Oil, general
purpose

Royco 363

Royal Lubricants Co., Inc.

OG (Cont.)

MIL-PRF-7870

Oil, general
purpose

Petrotect
7870A

Penreco
106 South Main Street
Butler, PA 16001

Windsor
lube L-1018

Anderson Oil & Chemical
Co., Inc.
Portland, CT 06480

Octoil 70

Octagon Process, Inc.
596 River Road
Edgewater, NJ 07020

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MODEL 172
MAINTENANCE MANUAL
Table 1. Recommended Lubricants (continued)

I

SYMBOL

PROCUREMENT
SPECIFICATION

LUBRICANT
DESCRIPTION

PL

VV-P-236

Petrolatum
technical

Available Commercially

PG

SS-G-659

Powdered
Graphite

Available Commercially

GL

MIL-G-21164

High and Low
Temperature
Grease

PRODUCT
PART
NUMBER

SUPPLIER

Everlube
211-G Moly
Grease

E/M Corporation
Box 2200
Highway 52 N.W.
West Lafayette, IN 47906

Royco 64

Royal Lubricants Co., Inc.

GP

NONE

Number
10 weight,
non-detergent
oil

Available Commercially

OL

VV-L-800

Light Oil

Available Commercially

Grease, general
purpose

U000992

Cessna Aircraft Co.
1 Cessna Blvd.
Wichita, Ks
67277-7704

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
BATTERY TERMINALS - SERVICING

1.

General
A.

2.

It is recommended the airplane be secured in an area free of contamination from sand, dust or other
environmental conditions that may contribute to improper lubrication practices.

Battery Terminal Lubrication
A.

Battery terminals should be lubricated when cables are installed to terminals.

B.

Refer to Figure 301 for lubrication requirements of the battery terminals.

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MODEL 172
MAINTENANCE MANUAL

B1671

Q

ITEM
NUMBER

ITEM
DESCRIPTION

LUBE
TYPE

APPLICATION

1

BATTERY
TERMINALS

PL

HAND

PL - GREASE, PETROLATUM - VV - P-236
0518T1023

Battery Terminals Lubrication
Figure 301 (Sheet 1)

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MODEL 172

MAINTENANCE MANUAL
LANDING GEAR AND PARKING BRAKE - SERVICING
1.

General
A.

2.

It is recommended that the airplane be secured in an area free of contamination from sand, dust or
other environmental conditions that may contribute to improper lubrication practices.

Wheel Bearing Lubrication
A.

Wheel bearings should be lubricated every 100 hours.

WARNING: WIEN CLEANING WHEEL BEARINGS, USE LOW PRESSURE
SHOP AIR TO DRY BEARINGS. DO NOT SPIN BEARING
CONES WITH COMPRESSED AIR. DRY BEARINGS WITHOUT
LUBRICATION MAY EXPLODE AT HIGH RPM.
B.
3.

4.

5.

6.

Nose Gear Torque Link Lubrication
A.

Nose gear torque links should be lubricated every 50 hours.

B.

Refer to Figure 301 for lubrication requirements of the nose gear torque links.

Shimmy Dampener Pivots Lubrication
A.

Shimmy dampener pivots should be lubricated on an "as needed" basis and when assembled or
installed.

B.

Refer to Figure 301 for lubrication requirements of the shimmy dampener pivots.

Steering System Needle Bearing Lubrication
A.

Steering system needle bearings should be lubricated on an "as needed" basis and when assembled
or installed.

B.

Refer to Figure 301 for lubrication requirements of the steering system needle bearings.

Nose Gear Steering Pushrods Lubrication
A.

7.

Refer to Figure 301 for lubrication requirements of the wheel bearings.

Nose gear steering pushrods should be lubricated every 100 hours using OG lubricant applied with
an oil can.

Parking Brake Handle Shaft Lubrication
A.

The parking brake handle shaft should be lubricated on an "as needed" basis and when assembled
or installed.

B.

Refer to Figure 301 for lubrication requirements of the parking brake handle shaft.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1672

2

5

1

NOSE GEAR

MAIN GEAR

ITEM
NUMBER

ITEM
DESCRIPTION

LUBE
TYPE

APPLICATION

1

WHEEL BEARINGS

GR

HAND

2

TORQUE LINKS

GR

GUN

3

SHIMMY DAMPER PIVOTS

OG

OIL CAN

4

NEEDLE BEARINGS

GR

HAND

5

PARKING BRAKE HANDLE
SHAFT

OG

OIL CAN

GR - GREASE, GENERAL PURPOSE - (MIL-G-81322)
OG - OIL, GENERAL PURPOSE - (MIL-L-7870)
0542T2001
0514T3001
0541T3001

Landing Gear Lubrication
Figure 301 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
FLIGHT CONTROLS - SERVICING

1.

General
A.

2.

3.

It is recommended that the airplane be secured in an area free of contamination from sand, dust or
other environmental conditions that may contribute to improper lubrication practices.

Aileron System Lubrication
A.

Bearings in the control column should be lubricated on an "as needed" basis and when assembled or
installed.

B.

Piano hinges on the ailerons should be lubricated on an "as needed" basis and when assembled or
installed.

C.

Needle bearings on the aileron bellcrank should be lubricated every 1,000 hours.

D.

Rod end bearings on the aileron bellcrank should be lubricated every 1,000 hours.

E.

Refer to Figure 301 for lubrication requirements of the aileron system.

Flap System Lubrication
A.

Flap motor screw jack threads should be lubricated every 100 hours. To lubricate the jack screw,
operate flaps to full down position, clean screw threads with solvent rag, dry with compressed air and
lubricate per Figure 302.
NOTE:

4.

B.

Needle bearings should be lubricated on an "as needed" basis and when assembled or installed.

C.

Refer to Figure 302 for lubrication requirements of the flap system.

Elevator System Lubrication
A. Bearings in the trim wheel controls should be lubricated on an "as needed" basis and when assembled
or installed.
B.

Trim tab piano hinges should be lubricated on an "as needed" basis and when assembled or installed.

C.

The trim tab actuator should be lubricated on an "as needed" basis". If trim tab inspection reveals
excessive free play, the first item of recourse should be to lubricate and remeasure. Lubrication
is accomplished by unscrewing the jackscrew and applying lubricant to the internal portion of the
actuator. This lubrication may bring free play back with limits. If not, actuator should be overhauled.
NOTE:

D.
5.

It is not necessary to remove actuator from airplane to clean or lubricate threads.

Carefully count and record the number of turns required to remove jackscrew from actuator.
Upon reassembly, the jackscrew should be threaded into the actuator using exactly the
same number of turns as recorded during disassembly.

Refer to Figure 303 for lubrication requirements of the elevator system.

Rudder System Lubrication
A.

The rudder bar bearings and linkage point pivots should be lubricated on an "as needed" basis and
when assembled or installed.

B.

Refer to Figure 304 for lubrication requirements of the rudder system.

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B1673

3

2

2

-

1

1^\
-z

ITEM
NUMBER

ITEM
DESCRIPTION

LUBE
TYPE

APPLICATION

1

NEEDLE BEARINGS

GR

HAND

BUSHINGS AND
OILITE BEARINGS

OG

OIL CAN

CONTROL TUBE
UNIVERSAL JOINTS

OG

OIL CAN

2

0560T3001

Aileron System Lubrication
Figure 301 (Sheet 1)

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B1674

5

4

ITEM
NUMBER

5

ITEM
DESCRIPTION

LUBE
TYPE

APPLICATION

ALL PIANO
HINGES

PG

SYRINGE

BELLCRANK
NEEDLE BEARINGS

GR

HAND

GR - GREASE, GENERAL PURPOSE - (MIL-G-81322)
OG - OIL, GENERAL PURPOSE - (MIL-L-7870)
PG - POWDERED GRAPHITE - (SS-G-659)

0561T1002
0561T1001

Aileron System Lubrication
Figure 301 (Sheet 2)

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B1675

1

ITEM
NUMBER

ITEM
DESCRIPTION

LUBE
TYPE

APPLICATION

1

SCREW JACK THREADS

GP

OIL CAN

GP - OIL, NO. 10 WEIGHT, NONDETERGENT

0564T2003

Flap System Lubrication
Figure 302 (Sheet 1)

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B1676

1

ITEM
NUMBER

ITEM
DESCRIPTION

LUBE
TYPE

APPLICAITION

ELEVATOR TRIM
TAB ACTUATOR

GL

HAND

GL - MOLYBDENUM DISLULFIDE GREASE - (MIL-G-21164)

0563T1004

Elevator Trim Lubrication
Figure 303 (Sheet 1)

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B1677

ITEM
NU MBER
1

ITEM
DESCRIPTION

LUBE
TYPE

APPLICATION

OILITE BEARING
(RUDDER BAR ENDS)

OG

OIL CAN

ALL LINKAGE
PIVOT POINTS

OG

OIL CAN

OG - OIL, GENERAL PURPOSE - (MIL-L-7870)

0562T2002

Rudder Pedals Lubrication
Figure 304 (Sheet 1)

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MAINTENANCE MANUAL
ENGINE CONTROL CABLES - SERVICING
1.

General
A.

2.

It is recommended that the airplane be secured in an area free of contamination from sand, dust or
other environmental conditions that may contribute to improper lubrication practices.

Engine Control Cables Lubrication
A.

All housed, pull-type, push-pull or vernier controls should have each outer housing lightly lubricated
internally with VV-L-800 General Purpose Lube Oil.

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HEATING AND VENTILATION CONTROL CABLES - SERVICING
1.

General
A.

2.

It is recommended that the airplane be secured in an area free of contamination from sand, dust or
other environmental conditions that may contribute to improper lubrication practices.

Heating And Ventilation Control Cables Lubrication
A.

All housed, pull-type, push-pull or vernier controls should have each outer housing lightly lubricated
internally with VV-L-800 General Purpose Lube Oil.

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MAINTENANCE MANUAL
AIRPLANE EXTERIOR - CLEANING/PAINTING
1.

2.

3.

General
A.

The airplane should be washed frequently in order to maintain its appearance and minimize corrosion.
The painted area of the airplane should be polished at periodic intervals to remove chalking paint and
restore its gloss.

B.

Water/detergent cleaning is the preferred method to clean the exterior surface of the airplane.

Precautions
A.

Read and adhere to all manufacturers instructions, warnings and cautions on the cleaning/solvent
compounds used.

B.

Do not use silicone based wax to polish the airplane exterior. Silicone based wax, especially if buffed
to produce a high shine, will contribute to the build up of P-static.

C.

Do not park or store airplane where it might be subjected to direct contact with fluid or vapors from
methanol, denatured alcohol, gasoline, benzene, xylene, methyl n-propyl ketone, acetone, carbon
tetrachloride, lacquer thinners, commercial or household window cleaning sprays, paint strippers or
other types of solvents.

D.

Do not leave sun visors up against windshield when not in use. The reflected heat from these items
causes elevated temperatures on the windshield. If solar screens are installed on the inside of the
airplane, ensure they are the silver appearing, reflective type.

Preventive Maintenance
A.

Keep all surfaces of windshields and windows clean.

B.

If desired, wax acrylic surfaces.

C.

Carefully cover all surfaces during any painting, powerplant cleaning or other procedure that calls for
use of any type of solvent or chemical. Table 701 lists approved coatings for use in protecting surfaces
from solvent attack.

Table 701. Approved Protective Coatings
NAME

NUMBER

Spray

MIL-C-6799,
Available Commerically
Type 1, Class II

Protect surfaces from
solvents.

Masking Paper

WPL-3

Champion Intl. Corp.
Forest Product Division
7785 Bay Meadows Way
Jacksonville, FL 32256

Protect surfaces from
solvents.

Poly-Spotstick

SXN

Champion Intl. Corp.

Protect surfaces from
solvents.

Mask Off Company
345 Marie Avenue
Monrovia, CA

Protect surfaces from
solvents.

Protex 40

MANUFACTURER

USE

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4.

Windshield and Window Cleaners

CAUTION: Do not use gasoline, alcohol, benzene, acetone, carbon tetrachloride, fire
extinguisher fluid, deicer fluid, lacquer thinner or glass window cleaning
spray. These solvents will soften and craze the plastic.
NOTE:

Equivalent substitutes may be used for the following items:

Table 702. Windshield and Window Cleaners/Polishers

NAME

NUMBER

Mild soap or
detergent (hand
dishwashing type
without abrasives)
Aliphatic Naphtha
Type II

Federal
Specification
TT-N-95

Turtle Wax (paste)

Permatex Plastic
Cleaner No. 403D
Soft cloth (cotton
flannel or cotton
terry cloth)
5.

Federal
Specification
P-P-560

MANUFACTURER

USE

Commercially Available

Cleaning windshields
and windows.

Commercially Available

Removing deposits which
cannot be removed with
mild soap solution on
acrylic windshields and
windows.

Commercially Available

Waxing acrylic
windshields and
windows.

Permatex Company, Inc.
Kansas City, KS 66115

Waxing acrylic
windshields and
windows.

Commercially Available

Applying and removing
wax and polish.

Cleaning Windshield and Windows

CAUTION: Windshields and windows are easily damaged by improper handling and
cleaning techniques.
CAUTION: Do not use any of the following for cleaning windshields and windows:
methanol, denatured alcohol, gasoline, benzene, xylene, methyl
n-propyl ketone, acetone, carbon tetrachloride, lacquer thinners,
commercial or household window cleaning sprays.
A.

Refer to Table 702 for cleaning materials.

B.

Windshield Cleaning Procedures.
(1) Place airplane inside hanger or in shaded area and allow to cool from heat of sun's direct rays.
(2) Using clean (preferably running) water, flood surface. Use bare hands with no jewelry to feel
and dislodge any dirt or abrasive materials.
(3) Using a mild soap or detergent (such as dish washing liquid) in water, wash surface. Again use
only bare hands to provide rubbing force. (A clean cloth may be used to transfer soap solution
to surface, but extreme care must be exercised to prevent scratching surface.)
(4) On acrylic windshields and windows only, if soils that cannot be removed by a mild detergent
remain, Type II aliphatic naphtha applied with a soft clean cloth may be used as a cleaning
solvent. Be sure to frequently refold cloth to avoid redepositing soil and/or scratching windshield
with any abrasive particles.

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(5) Rinse surface thoroughly with clean fresh water and dry with a clean cloth.
6.

Waxing and Polishing Windshield and Windows

CAUTION: Do not use rain repellent on acrylic surfaces.
NOTE:
A.
B.

7.

Refer to Table 702 for polishing materials.
Hand polishing wax (or other polish meeting Federal Specification P-P-560) should be applied to
acrylic surfaces. The wax has an index of refraction nearly the same as transparent acrylic and tends
to mask any scratches on windshield surface.

Aluminum Surfaces
A.

8.

Windshields and windows must be cleaned prior to application of wax. When applying and
removing wax and polish, use a clean soft cloth.

Aluminum surfaces require a minimum of care, but should never be neglected. The airplane may
be washed with clean water to remove dirt and may be washed with non alkaline grease solvents to
remove oil and/or grease. Household type detergent soap powders are effective cleaners, but should
be used cautiously, since some of them are strongly alkaline. Many good aluminum cleaners, polishes
and waxes are available from commercial suppliers of airplane products.

Painted External Surfaces

CAUTION: Do not let solvents come in contact with the external graphics. The
external graphics can be easily damaged by contact with solvents. For
care and cleaning of the external graphics, refer to Chapter 12, Exterior
Graphics - Maintenance Practices.

9.

A.

Generally, the painted surfaces can be kept bright by washing with water and mild soap, followed by
a rinse with water and drying with cloths or a chamois. Harsh or abrasive soaps or detergents which
could cause corrosion or scratches should never be used. Remove stubborn oil and grease with a
cloth moistened with Stoddard solvent.

B.

To seal any minor surface chips or scratches and protect against corrosion, the airplane should
be waxed regularly with a good automotive wax applied in accordance with the manufacturer's
instructions. If the airplane is operated in a seacoast area or other salt water environment, it must be
washed and waxed more frequently to assure adequate protection. Special care should be taken
to seal around rivet heads and skin laps, which are the areas susceptible to corrosion. A heavier
coating of wax on the leading edges of the wings and tail and on the cowl nose cap and propeller
spinner will help reduce the abrasion encountered in these areas. Reapplication of wax will generally
be necessary after cleaning with soap solutions or after chemical deicing operations.

Engine and Engine Compartment Washing
A.

Notes and Precautions.
(1) An engine and accessories wash down should be accomplished during each 100 hour inspection
to remove oil, grease, salt corrosion or other residue that might conceal component defects
during inspection. Also, periodic cleaning can be very effective In preventive maintenance.
(2) When working with cleaning agents, protective devices (rubber gloves, aprons, face shields,
etc...) should be worn. Use the least toxic of available cleaning agents that will satisfactorily
accomplish the work.
(3) All cleaning operations should be performed in a well ventilated work area.
(4) Adequate fire fighting and safety equipment should be available.

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WARNING: Do not smoke or expose a flame within 100 feet of the cleaning
area.
(5) Compressed air, if used to apply solvent or to dry components, should be regulated to lowest
practical pressure.
(6) Use of a stiff bristle brush (as opposed to a steel brush) is recommended if cleaning agents do
not remove excess grease and grime during spraying.
B.

Cleaning Procedures.
(1) Remove engine cowling.
(2) Carefully cover the coupling area between vacuum pumps and engine drive shafts so no cleaning
solvent can reach coupling or seal.
(3) Cover open end of the vacuum discharge tubes.
(4) If engine is contaminated with salt or corrosive chemicals, first flush engine compartment with
fresh water.

CAUTION: Do not use gasoline or other highly flammable substances for wash
down.
CAUTION: Do not attempt to wash an engine which is still hot or running. Allow
engine to cool before cleaning.
CAUTION: Care should be exercised to not direct cleaning agents or water
streams at openings on the starter, magnetos, alternator or vacuum
pump.
(5) Apply solvent or cleaning agent to engine compartment. The following solutions (or their
equivalent) can be used to satisfactorily clean the engine compartment:
(a) Stoddard Solvent (Specification P-D-680, Type II).
(b) Water alkaline detergent cleaner (MIL-C-25769 mixed 1 part cleaner, with 2 to 3 parts water
and 8 to 12 parts Stoddard Solvent).
(c) Solvent based emulsion cleaner (MIL-C-4361 mixed 1 part cleaner with 3 parts Stoddard
Solvent).
(6) After applying solvent, thoroughly rinse with clean warm water.
NOTE:

Cleaning agents should never be left on engine components for an extended period of
time. Failure to remove them may cause damage to components such as neoprene
seals and silicone fire sleeves, and could cause additional corrosion.

(7)
(8)
(9)
(10)

Completely dry engine and accessories using clean, dry compressed air.
Remove protective cover over coupling area.
Remove protective cover from vacuum discharge tube.
If desired, engine cowling may be washed with the same cleaning agents, then rinsed thoroughly
and wiped dry. After cleaning engine, relubricate all control arms and moving parts as required.
(11) Reinstall engine cowling.

WARNING: Ensure magneto switches are off, throttle is closed, mixture
control is in the idle cutoff position, and the airplane is secured
before rotating propeller by hand. Do not stand within arc of
the propeller blades while turning propeller.
(12) Before starting engine, rotate propeller by hand no less than four complete revolutions.

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10.

Propeller
A.

11.

The propeller should be wiped occasionally with an oily cloth to remove grass and bug stains. In salt
water areas, this will assist in corrosion proofing the propeller.

Tires and Wheels
A.

Remove oil, grease, and mud from tires and wheels with soap and water.

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MAINTENANCE MANUAL
AIRPLANE INTERIOR - CLEANING/PAINTING
1.

General
A.

2.

Airplane Interior - Cleaning/Painting gives procedures for different types of cleaning agents and
cleaning procedures for the interior of the airplane.

Interior Cleaning Materials
NOTE:

Equivalent alternatives can be used for the items that follow.

NAME

NUMBER

MANUFACTURER

USE

Son Of A Gun

Commercially available

To give protection for
interior components
(does not include fabric
materials).

Fantastic

Commercially available

To general purpose clean
interior components and
recommended to clean
Morbern vinyl.

Commercially available

To remove tar, asphalt,
etc., from interior.

Rug Shampoo

Commercially available

To clean carpet.

Perchloroethylene
Cleaning Solvent

Commercially available

To spot clean carpet and
seats.

Stoddard Solvent

Commercially available

To clean nylon safety
belts.

Ivory Liquid (White or
colorless)

Commercially available

To clean seat fabric.

Cheer

Commercially available

To clean seat fabric.

Mr. Clean

Commercially available

Recommended to clean
Morbern vinyl.

Aliphatic Naphtha

3.

To Clean Interior Panels
A.

4.

TT-N-95

Interior panels are made of a heavy vinyl and can have a softer Morbern vinyl cover. You can clean
the interior panels with a mild detergent solution or with pre-mixed commercial cleaners. You can
remove contamination that is not easily removed with aliphatic naphtha. Make sure the cleaners will
work on the interior without damge. If it is not sure that the cleaner will cause damage to the interior,
apply a small quantity of cleaner to a not visible location and do a test to see if it will cause damage.

To Clean Carpet
A.

The carpet is made of a polypropylene weave put together with a fire retardant backing. The
polypropylene gives stain resistant qualities and normally only minimal maintenance is required.

B.

If the carpet becomes contaminated, it can be cleaned with a commercially available carpet cleaning
agent.

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5.

To Clean Seats
A.

Fabric seats of the 172R and some 172S are made of a flame retardant Trevira polyester fiber and
have fire-retardant and stain-resistant properties. You must clean the seats regularly. Contamination
and stains must be cleaned up immediately and the fabric cleaned before the stains set up in the
fabric.

B.

Table 701 (Procedures to Clean Trevira Fabric on Seats) and Table 702 (Procedures to Clean Morbern
Vinyl on Cabin Panels) are given to help in stain removal. The tables have two columns; one with the
stain and the other with the procedure to remove the stain. For example, coffee and tea stains are
removed with processes 2, 4, 5 and 1. The first step is the application of process 2 (dishwashing liquid
with warm water) to the stain. The second step is the application of process 4 (vinegar and water) to
the stain. The third step is the application of process 5 (laundry powder and warm water followed by
blotting) to the stain. The final step is the application of process 1 (dry cleaning solvent applied to the
stain).

Table 701. Procedures to Clean Trevira Fabric on Seats
STAIN

PROCESS/SEQUENCE

STAIN

PROCESS/SEQUENCE

Antacid (Maalox)

1

Infant Formula

2,1

Betadine (Iodine)

2,3,4,6

Ink (ball point)

8

Blood

2,3,5

Motor Oil

1,2,3,4

Catsup

2,3,5

Mud

2,1

Chewing Gum

7,1,2

Petroleum Jelly

1,2

Chocolate Syrup

5,1

Pepto Bismol

6,1

Coffee/Tea

2,4,5,1

Urine

2,3,4

Cola

2,3,4

Suntan Lotion

1,2

Cough Syrup

2

Shoe Polish

1,2,3

Egg

2,3,5,1

Vomit

2,3,4,5

Grape Drink

2,3,4,5

Wax

7,1

Ice Cream

2,3,4,5,1

1.
2.
3.
4.
5.
6.
7.
8.
NOTE:

Apply a small quantity of dry cleaning solvent to the stain. Do not smoke or use near an open
flame. Use sufficient airflow.
Mix one teaspoon of white or colorless dishwashing liquid with a cup of lukewarm water.
Mix one tablespoon of household ammonia with half a cup of water.
Mix one part household vinegar with two parts water.
Mix a solution of laundry powder with water and leave on the stain according to the label directions.
Flush with warm water and wipe dry.
Mix one part household bleach with nine parts water. Use a dropper to apply the solution to the
stain. Flush with water and wipe dry.
Chill area with an ice cube wrapped in a plastic bag. Remove the gum or wax from the surface of
the fabric.
Apply a small quantity of rubbing alcohol to the ink stain and blot to remove the ink. Continue until
the ink is removed.
All solutions must be cool when applied to the stain. Heat from the solutions will permanently
set the stain.

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Table 702. Procedures to Clean Morbern Vinyl on Cabin Panels
STAIN

PROCESS/SEQUENCE

STAIN

PROCESS/SEQUENCE

Blood

4

Mud

3,6

Candy, Ice Cream

14,6

Mustard

3,12,8,6

Chewing Gum

11,6

Paint, Latex

9,6

Crayon

3,12,8,6

Paint, Oil base

2,3

Fruit Stains

14,6

Shoe Polish

13,6

Ink (ballpoint)

1

Soft Drinks

14,6

Ketchup

3,12,8,6

Surface Mildew

8,6

Lipstick, Eyeshadow

13,6

Tar, Asphalt

10,3

Liquor, Wine

14,6

Urine

7,6

5,6
Vomit
13,6
Motor Oil, Grease
1. Apply a small quantity of rubbing alcohol to the ink stain and blot to remove the ink. Continue until
the ink is removed.
2. Turpentine in a well ventilated area will remove fresh paint. Dried paint must be moistened carefully
with a semi-solid gel-type stripper so that the softened paint can be gently scraped away.
CAUTION:

Direct contact with paint strippers will remove the print pattern from

vinyl. Paint strippers are very corrosive. Be careful to avoid skin and
eye contact. Wear safety equipment, If applicable.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

NOTE:

Flush with mild soap and water.
Rub out any spots with a clean cloth soaked in cool water. If spots remain, use household ammonia
and flush with a clean, wet cloth.
Sponge the stained area with soapy water that contains diluted bleach until the stain is removed.
Flush thoroughly with clean, cool water.
Sponge with soapy water that contains a small quantity of household ammonia.
Wash with diluted bleach and use a soft brush for difficult stains.
Fresh paint can be wiped off with a damp cloth. Hot, soapy water will normally remove dried latex.
Remove immediately, as prolonged contact will result in a permanent stain. Use a cloth lightly
dampened with mineral spirits or kerosene and rub the stain gently. Work from the outer edge of
the stain towards the center in order to prevent the spread of the stain.
Scrape off as much as possible with a dull knife. Rub with an ice cube to help make it easier to
remove the gum. The remaining gum can then be removed in a well ventilated area with a cloth
saturated with mineral spirits. Rub lightly.
Flush with a mild detergent and water.
Apply a small quantity of mineral spirits with a clean soft cloth. Rub gently. Be careful to not
spread the stain. Remove shoe polish as soon as possible, as it contains a dye which will cause
a permanent stain.
Flush thoroughly with clean, lukewarm water. Repeat as necessary. Scrape the area gently with
a dull knife to remove any loose material. Any soiled area remaining after the area dries can be
gently rubbed with a cloth spotted with a small quantity of alcohol.
All solutions must be cool when applied to the stain. Heat from the solutions will permanently
set the stain.

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6.

To Clean the GDU 1040 Display Lens
NOTE:

The Primary Flight Display (PFD) and Multi-Function Display (MFD) are the GDU 1040 displays
in airplanes with Garmin G1000.

CAUTION: If possible, do not touch the lens. The GDU 1040 lens has a layer of antireflective material which Is very sensitive to skin oils, waxes and abrasive
cleaners.
CAUTION: Do not use cleaners that contain ammonia. Ammonia will cause damage to
the anti-reflective material.
A.

Clean the GDU 1040 Display Lens.
(1) Use a clean, lint-free cloth and an eyeglass lens cleaner that is specified as safe for anti-reflective
material to clean the lens.

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MAINTENANCE MANUAL
EXTERIOR GRAPHICS - MAINTENANCE PRACTICES
1.

General
This section gives general instructions for removal/installation and preservation for the exterior
graphics (decals) on the airplane.

A.
2.

Tools and Equipment
NOTE:

Equivalent alternatives can be used from the list of items that follows:

Table 201. Graphics Application Tools
NAME

NUMBER

MANUFACTURER

USE

Isopropyl Alcohol

None

Commercially Available

To prepare airplane
surface for graphics
application.

Sharpline Primer

None

Sharpline Converting Inc.
1520 S. Tyler Road
Box 9608
Wichita, KS 67277

To give additional
adhesion of graphics
to the airplane around
the rivet heads.

Desothane

CA 8000/
B900B

PRC-DeSoto International
5454 San Fernando Road
Glendale, CA 91209
Phone: (818) 240-2060

To seal the edge of a
graphic.

Primer Remover

Acti-Sol

Sharpline

To remove the primer.

Dense, closed cell
foam block

1" X 2" X 2"

Fabricate Locally

To help apply graphics
around rivets.

Needle

None

Commercially Available

To puncture air bubbles.

Artist's Paint
Brush

None

Commercially Available

To apply the primer to the
airplane.

Squeegee

None

Commercially Available

To help apply graphics to
the flat surfaces.

NOTE:

The table that follows gives a list of paint and related chemicals used on the airplane.

Table 202. Interior and Exterior Paint
NAME

NUMBER

MANUFACTURER

Fuel Bay Primer

Conventional 454-4-1
Base

AKZO Nobel Aerospace Epoxy primer for
the inner surfaces
Coatings
East Water Street
of the wing fuel
Waukegan, IL 60085
compartments.

CA109

AKZO Nobel Aerospace
Coatings

Used with fuel
tank epoxy primer
(conventional).

High Solids 10P30-5
Base

AKZO Nobel Aerospace
Coatings

Epoxy primer for
the inner surfaces
of the wing fuel
compartments.

Activator

Fuel Bay Primer

USE

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MAINTENANCE MANUAL
Table 202. Interior and Exterior Paint (continued)
NAME

NUMBER

MANUFACTURER

USE

Activator

EC275

AKZO Nobel Aerospace
Coatings

Used with fuel tank
epoxy primer (high
solids).

Thinner

TR115

AKZO Nobel Aerospace
Coatings

Used with fuel tank
epoxy primer (high
solids).

Overall Primer/Sealer
(Note 1)

483-928

Sherwin Williams
16116 E. 13th St.
Wichita, KS 67230

Applied to the airplane
before topcoat.

Hardener

120-828

Sherwin Williams

Used with Sherwin
Williams primer/sealer.

G2HC 4175

Omega Coatings
Corporation
PO Box 1319
El Dorado, KS 67042

Applied to the airplane
before topcoat.

G2HE0175

Omega Coatings
Corporation

Used with Omega
primer/sealer.

830 Series High Solids
Acry Glo Color Code
AO-150 (Matterhorn
White)

Sherwin Williams

Topcoat overall color.

Hardener

830-081

Sherwin Williams

Used as a catalyst for
Acry Glo.

Accelerator

830-H 18

Sherwin Williams

Decrease cure time of
Acry Glo.

AF3102 Imron High
Solids (Matterhorn
White)

Du Pont
Du Pont Performance
Coatings
Willmington, DE 19898

Topcoat overall color.

Activator

194S

Du Pont

Used as a catalyst for
AF3102 Imron.

Reducer

2165S

Du Pont

Used as a reducer for
AF3102 Imron.

Pot Life Extender

TP31124

Du Pont

Extends potlife for
AF3102.

728-014

Sherwin Williams

Treatment of surfaces
before the application of
primer.

Overall Primer
(Note 2)

Hardener
Topcoat
(Note 3)

Topcoat
(Note 4)

Wash Primer

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Table 202. Interior and Exterior Paint (continued)
NAME
NUMBER
Adduct

MANUFACTURER

USE

702-701

Heat Resistant Enamel (Gray)

521-520

Sherwin Williams

Engine mount and
engine mount hardware
in engine compartment.

Cloth

Cheese cloth

Commercially available

Used with solvent to
clean airplane exterior.

Note 1: This product is for airplanes manufactured before June 2002.
Note 2: This product is for airplanes manufactured after June 2002.
Note 3: This product is for airplanes manufactured before January 2004.
Note 4: This product is for airplanes manufactured after January 2004.
3.

Graphics Removal/Installation
A.

Remove the Graphics (Refer to Figure 201).
(1) If you install a new graphic, you must show reference marks on the airplane before you remove
the old graphic. The reference marks will help to position the new graphic on the airplane.

CAUTION: Do not heat the airplane surface more than 250°F (12°1C) or
damage to the paint will result.
(2) Apply heat with a heat gun to the surface of the graphic.
(3) Carefully separate a corner of the graphic from the airplane.
(4) Apply primer remover between the graphic and airplane to loosen the adhesive-backed graphic.
Refer to Table 201.

CAUTION: Do not pull the graphic out (perpendicularto surface) and away from
the airframe. If you do not pull the graphic clown (so It Is parallel to
the surface), you will remove paint from the airplane.
(5) Pull down on the graphic parallel to the surface with a firm, slow movement.
(6) Continue to apply primer remover to the glued side of the graphic as you remove the graphic
from the airplane.
(7) Discard the old graphic.
(8) Use the primer remover to remove all adhesive from the airplane.
(a) Make sure all adhesive is removed from areas around the rivet heads.
B.

Install the Graphics (Refer to Figure 201).

CAUTION: Install graphics only after the exterior paint Is cured. If the paint Is not
cured, solvents will be left In the film that can cause damage to the
graphics.
NOTE:

The center hinge method will help to correctly set in position the large graphics.

NOTE:

The graphic has a protective backing (paper liner), the adhesive-backed graphic (decal),
and a protective outer film.

(1) Use isopropyl alcohol and primer remover as necessary to clean the surface of the airplane.
Refer to Table 201.
(a) Make sure any amount of old adhesive is removed from the airplane surface.

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B1656

/////7
DECAL

0510T1009

Decal Application
Figure 201 (Sheet 1)

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(2) Apply Sharpline Primer on and around each rivet approximately 0.25 inch (6.35 mm) beyond the
head with a small artist's paint brush. Let the primer dry for 15 minutes at 75°F (24°C).
(3) To help install large graphics, use reference marks from the old graphic and set the new graphic
in position with a piece of masking tape installed vertically across the center of the graphic.
NOTE:
(4)
(5)

(6)

(7)

(8)

(9)
(10)
(11)
(12)
(13)
(14)
4.

The use of the masking tape set vertically across the center of the graphic is known
as the center hinge method.

Remove the paper liner from the back of the new graphic to show the adhesive. For large
graphics that use the center hinge method, remove one half of the graphic paper liner.
Apply the graphic to airplane.
(a) Use the reference marks from the old graphic to position the new graphic on the airplane.
(b) Use a squeegee to make sure that no wrinkles or bubbles show on the surfaces of the
airplane. At the area where the graphic overlays on rivets, the graphic must be stretched
over the rivet heads to prevent a wrinkle development.
(c) The graphic must adhere to the top of the rivet and to the area around the airplane structure.
Air that has been trapped around the base of the rivets will be removed in a later step.
For large graphics that use the center hinge method, remove the second half of the graphic
paper lining.
(a) Use the reference marks from the old graphic to position the new graphic on the airplane.
(b) Use a squeegee to make sure that no wrinkles or bubbles show on the surfaces of airplane.
At the area where the graphic overlays on rivets, the graphic must be stretched over the
rivet heads to prevent a wrinkle development.
(c) The graphic must adhere to the top of the rivet and to the surrounding airplane structure.
Air that has been trapped around the base of the rivets will be removed in a later step.
Remove the premask (outer protective film) from the graphic when it has been fully applied to
the airplane.
(a) Use Desothane as an edge sealer to minimize graphic delamination and peel at the vinyl
leading edges. Desothane must also be used to promote graphic adhesion where rivets
are 0.25 inch (6.35 mm) from the vinyl edges.
Remove any air bubbles from rivets in the steps that follow.
(a) Puncture the air bubble 8 to 12 places around the rivet with a small needle.
(b) Use a heat gun to warm the graphic and structure around each rivet to approximately 125°F
(52°C).
(c) Use a dense, closed cell foam block (Temperfoam or equivalent to work out all bubbles
from around the rivet head).
Use a needle to puncture any air bubbles from the flat areas of the graphic.
Use a squeegee to smooth the graphic.
When all bubbles have been removed, warm the full graphic for 10 minutes to 15 minutes at
125°F (52°C) to 130°F (54°C).
Remove any primer with primer remover after the surface has cooled to room temperature.
Trim the graphics to be flush with the areas of termination such as the doors and cowl.
Adhesive cure time must be a minimum of 72 hours and recorded in the maintenance log.

Exterior Graphics Preservation
A.

Clean the Exterior Graphics.
NOTE:

The procedures that follow must be obeyed to make sure of the maximum service life for
the graphic.

(1) Wash the graphic with soap and water.
(2) Rinse the graphic after you wash it.
(3) If you use a high pressure washer, keep the nozzle at least two feet from the edge of the graphic.
(4) Do not use acetone, methyl n-propyl ketone, toluene, paint thinner, lacquer thinner or other
aromatic solvents to clean the graphic.
(5) Test other cleaning solutions on a small corner of the graphic before you use it.
(6) Do not overcoat the graphic with clear paint.

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I

(7)
(8)
(9)

Do not let fuel spill on the graphics.
(a) Wipe off and flush with water immediately if fuel spills on the graphics.
Do not paint over the graphics.
Do not apply wax over the graphics.

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UNSCHEDULED SERVICING - DESCRIPTION AND OPERATION
1.

General
A.

This section gives procedures and recommendations for normally unscheduled servicing.

B.

Instructions are given in the Cold Soak procedures for operation of the airplane during very cold
temperatures.
NOTE:

2.

Extreme Weather Maintenance
A.

3.

During operation at outside air temperatures below International Standard Atmosphere
(ISA) Standard, the engine can develop more than its rated power at normal-rated RPM.
This occurs more at lower altitudes.

Seacoast and Humid areas.
(1) In salt water areas, special care should be taken to keep engine, accessories, and airframe
clean to help prevent oxidation.
(2) In humid areas, fuel and oil should be checked frequently and drained of condensation to prevent
corrosion.

Cold Soak
cold soak. If the airplane has cold soaked for more than two hours at temperatures colder than -10°C
(14°F), refer to this procedure and the Pilot's Operating Handbook and FAA Approved Airplane Flight
Manual to prepare the airplane for flight.
(1) Cold temperatures have an effect on control cable tension. Refer to Chapter 27, Aileron Control
System - Maintenance Practices, Elevator Control System - Maintenance Practices, Elevator
Trim Control - Maintenance Practices, and Flap Control System - Maintenance Practices for
flight control cable tensions.
(2) For information on lubrication and greasing of moving parts, refer to Chapter 12, Lubricants Description and Operation.
(3) Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight Manual for the correct
engine oil viscosity.
(4) Refer to the Pilot's Operating Handbook and FAA Approved Airplane Flight Manual for additional
information on procedures for operation of the airplane in cold temperatures.
B.

The engine must be preheated before an engine start when exposed to very cold temperatures.
Preheat the engine as follows:
(1) Direct warm air into the engine cooling inlets behind the propeller.

CAUTION: Do not use air with a temperature of more than 120°C (248°F) when
you preheat the engine. Air with a temperature of more than 120°C
(248°F) can do damage to the exterior paint of the airplane.
(2) Make sure that the temperature of the warm air is no more than 120°C (248°F).

WARNING: Never bring open flames near the airplane. Use of a heater with
an open flame to preheat the engine can cause damage to the
airplane and injury to personnel.
(3) Do not use a heater with open flames to supply the warm air to preheat the engine.
(4) Preheat the engine before an engine start if the engine temperature is less than -6°C (20°F).

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(5) When the temperature is less than 0°C (32°F), preheat the engine to more than 0°C (32°F)
before you start the engine again after an engine start and stop.
NOTE:

I

When the temperature is less than 0°C (32°F), water from combustion can freeze to
the engine spark plugs if the engine does not continue to operate after it is started.
This will prevent the engine from starting again.

C.

The Garmin GDU 1040 PFD/MFD requires warm-up time when exposed to very cold temperatures.
(1) A warm-up time of up to 30 minutes is necessary when the GDU is exposed to down to -40°C
(-40°F) for an extended period.
(2) A warm-up time of up to 15 minutes is necessary when the GDU is exposed to down to -30°C
(-22°F) for an extended period.

D.

Before takeoff, preheat the airplane cabin to more than -30°C (-22°F) for correct operation of the
standby altimeter.
NOTE:

If there is no warning that an instrument is not operating correctly, all other instruments will
operate continuously until at the minimum temperature of the airplane.

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STANDARD
PRACTICES
AIRFRAME

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
STANDARD PRACTICES AIRFRAME - GENERAL .................
Scope....................................
Definition ..................................
MATERIAL AND TOOL CAUTIONS - DESCRIPTION AND OPERATION........
Titanium...................................
Mercury...................................
Asbestos ..................................
Cadmium Plated Fasteners..........................
Maintenance Precautions...........................
General Usage Solvents ...........................
National Emissions Standards for Hazardous Air Pollutants ...........
Facilities and Equipment ...........................
TORQUE DATA - MAINTENANCE PRACTICES...................
General...................................
Torque Requirements for Bolts, Screws and Nuts................
Torque Requirements for Hi-Lok Fasteners...................
Torque Requirements for Electrical Current Carrying And Airframe Ground
Fasteners.................................
Torque Requirements for Rigid Tubing and Hoses................
SAFETYING - MAINTENANCE PRACTICES ....................
General...................................
Safety Wire .................................
Safety Wire Installation............................
Cotter Pin Installation.............................
Safetying Turnbuckles ............................
SEALING - DESCRIPTION AND OPERATION....................
General...................................
ACCEPTABLE REPLACEMENTS FOR CHEMICALS AND SOLVENTS - DESCRIPTION
AND OPERATION ................................
General...................................
Hand-Wipe Cleaning Operations .......................
Priming Operations..............................
Topcoat Operations .............................
Paint Stripping Operations ..........................
GENERAL SOLVENTS/CLEANERS - MAINTENANCE PRACTICES .........
General...................................
Tools, Equipment and Materials........................
Safety Precautions..............................
Description .................................
INTERIOR AND EXTERIOR FINISH - CLEANING/PAINTING.............
General...................................
Interior and Exterior Finishes .........................
Paint Facility.................................
Sanding Surfacer ..............................
Paint Stripping................................
Hand Solvent Cleaning............................
Maintenance of the Interior and Exterior Primary Coatings and Topcoat......

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MODEL 172,
MAINTENANCE MANUAL
FUEL, WEATHER AND HIGH-TEMPERATURE
PRACTICES ...................................
General...................................
Tools and Equipment.............................
Definition of Sealing Terms ..........................
Materials ..................................
General Requirements............................
Sealant Curing................................
Mixing of Sealants..............................
Cleaning ..................................
Sealing Application..............................
Sealant Repair................................

SEALING

-

CONVERSION DATA - DESCRIPTION AND OPERATION ..............
General...................................
Conversion Factors .............................

MAINTENANCE
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MAINTENANCE MANUAL
STANDARD PRACTICES AIRFRAME - GENERAL
1.

2.

Scope
A.

This Chapter describes standard maintenance practices and safety precautions applicable to all
aspects of the airframe and related systems. Maintenance practices which are unique to a particular
system or subject are described in the appropriate chapter and section in the maintenance manual.

B.

For repairs beyond the scope of this manual, refer to the 1996 and On 100 Series Structural Repair
Manual.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief definition of the subjects
and sections incorporated in this chapter is as follows.
(1) The section on Material and Tool Cautions describes general cautions and warnings applicable
to maintenance on or around the airplane.
(2) The section on Torque Data provides tables, formulas, requirements and torque limits for various
type fasteners.
(3) The section on Safetying describes the proper methods and use of safety wire/lockwire, cotter
pins and lock clip installations.
(4) The section on Solvents describes characteristics of solvents which are commonly used during
maintenance, cleaning and inspection of various airframe and related components.
(5) The section on conversion data provides tables for converting english to metric measurements.

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MATERIAL AND TOOL CAUTIONS - DESCRIPTION AND OPERATION
1.

Titanium

CAUTION: Do not use cadmium-plated tools on titanium parts. Cadmium particles can
stay on such parts. The cadmium particles will cause an unwanted condition
with the titanium when heated. The titanium part will become brittle In the
area of the unwanted condition and make cracks.
CAUTION: Do not let cadmium-plated fasteners touch titanium parts.
2.

Mercury

CAUTION: Do not use thermometers and other mercury-based test equipment on the
airplane.
A.

3.

Corrosion Caused by Mercury.
(1) There is no known procedure to stop corrosion when it has started.
(2) Mercury can go into any crack in the finish, paint, or seal layer of a metal. An oxide layer on a
dry metal surface will prevent corrosion. A bright surface, a polished surface, or a surface with
scratches will increase the rate of corrosion.
(3) Dirt, grease, or other contaminants that have no effect on the metal surfaces will help prevent
corrosion.
(4) The corrosion and the embrittlement caused by corrosion can be very fast in structural members.

Asbestos

WARNING: Do not let asbestos fibers make entry Into the body of personnel.
Asbestos fibers can cause Injury or death.

4.

A.

Do not breathe the dust of asbestos fibers. To not breathe the dust of asbestos fibers, use either of
the methods that follows.
(1) Use engineering control, which includes work in a correctly filtered exhaust chamber. Use
wet procedures to keep personnel exposure limits less than those recommended by the
Occupational Safety Health Administration (OSHA).
(2) Use breathing equipment with high quality filters. Other protection must include protective
clothing, gloves and eye protection.

B.

Refer to all local, state, and federal regulations to discard asbestos material.

Cadmium Plated Fasteners

CAUTION: Put a complete layer of fuel sealant on cadmium-plated fasteners that are
used In fuel areas. Cadmium particles from cadmium-plated fasteners can
cause damage to the engine.
5.

Maintenance Precautions

WARNING: Obey the precautions during maintenance, repair, and service
procedures of the airplane to prevent the risk of Injury because of the
different materials and environmental conditions.
A.

Carefully read and follow all instructions.
(1) Obey all cautions and warnings given by the manufacturer of the product that is used.
(a) Use the applicable safety equipment such as goggles, face shields, breathing equipment,
protective clothing and gloves.
(2) Do not get dangerous chemicals in the eyes or on the skin.

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(3)
(4)
6.

Do not breathe the fumes of dangerous chemicals.
Make sure the work area has good airflow and the applicable breathing equipment is used when
composites or metals are sanded or work is done in an area where small particles can be made.

General Usage Solvents
A.

Airplane maintenance procedures frequently use solvents. A solvent is a material, usually a liquid,
that can break down another material. Solvents usually have no color, dry quickly, and give off fumes
in high quantities. Examples of general use solvents are as follows:
·
Methyl n-Propyl Ketone
Toluene
·
Isopropyl Alcohol
Acetone
·
Methylene Chloride
1,1,1 - Trichlorethane
·
Naptha
ASTM D4080

B.

Solvents can cause injury or death. Solvents usually have no color, dry quickly, and give off fumes in
high quantities. The fumes are usually heavier than air. The fumes can collect in low-level areas and
push air out of the areas that are not ventilated. This can remove the supply of oxygen from the area.
(1) The solvent fumes are usually heavier than air.
(2) The solvent fumes can be breathed. Use applicable breathing equipment.
(3) Solvents can cause damage to the hands and the skin.
(a) Solvents dry out the skin and remove the natural oils. Damaged skin can cause other
contamination to make the condition worse.
(b) The contamination has easier access to the lowest levels of the skin.
1
The human body can filter small amounts of solvents out of itself. This filtration
function takes place in the liver. The liver receives blood which can be contaminated
with solvents from both the lungs and the skin. If the quantities are low enough and not
too frequent, the liver can filter out the contaminants. This is one of the scientific facts
on which OSHA based its Permissible Exposure Limits. However, when exposures
are constantly above these levels and extend for many years, the filter (liver) becomes
clogged and the solvents can then have an unwanted effect on other parts/portions
of the body.

C.

Solvents are hazardous materials because of flammability. The rate of evaporation is related to
flammability. The fumes are usually needed to ignite the liquid. Any ignition source can ignite solvent
fumes. The low flash point of the solvent shows that the solvent can ignite easily. Usually the flash
points of less than 100°F (37.8°C) are thought to be flammable. Examples of solvent flash points are
as follows:
SOLVENT

D.

FLASH POINT

Methyl n-Propyl
Ketone

45°F (7.2°C)

Toluene

39°F (3.9°C)

Isopropyl Alcohol

53.6°F (12°C)

Acetone

1.4°F (-17°C)

Solvents can be explosive when mixed with chemicals that release oxygen (oxidizer). For this
reason, it is very important for personnel to know which chemicals are in use in the work area to
avoid accidental mixture of solvents and oxidizers.
(1) Know the container labels.
(a) Chemical manufacturers are required to put a label with a diamond-shaped symbol on each
container.
1
The red symbol on the label shows that the contents are flammable.
2
The yellow symbol on the label shows that the contents are oxidizers.

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7.

National Emissions Standards for Hazardous Air Pollutants
A. National Emissions Standards for Hazardous Air Pollutants (NESHAP).
(1) The NESHAP standards have put a limit on the use of certain chemicals and solvents.
(2) For complete details of the regulatory standards, see the Federal Register, 40 CFR Part 63,
[Ad-FRL-5636-1], RIN 2060-AG65.
B.

NESHAP Requirements.
(1) Hand-Wipe Cleaning.
(a) All hazardous air pollutants or organic compounds that release dangerous fumes that are
used as hand wipe cleaning solvents must meet a composition requirement and have a
vapor pressure less than or equal to 1.75 Hg at 69°(45 mm Hg at 20°C.)
(b) The requirements specified can be met by an alternative compliance plan used by the
applicable authority and approved under Section 112(1) of the Clean Air Act.
(2) Primer Application.
(a) The organic hazardous air pollutant content is limited to 350 g/l (2.9 pounds-per-gallon),
less water, as applied.
(b) The volatile organic compound limit is 350 g/l (2.9 pounds-per-gallon), less water, as
applied.
(c) Use coatings below the content limit or use monthly volume-weighted averaging to get the
content limits to meet content limits.
(3) Topcoat Application.
(a) The base coat organic hazardous air pollutant content must be less than 420 g/l (3.5
pounds-per-gallon), less water, as applied.
(b) The volatile organic compound limit is 420 g/l (3.5 pounds per gallon), less water, as
applied.
(c) The topcoats must meet the requirements of MIL-PRF-85285D.
(d) Stripe paint requirements are the same as the base coat requirements. If the recommended
supplier cannot be used, then use base coat materials to paint stripes.
NOTE:

All paints and primers must have specific application techniques. If an
alternative is supplied, use only the materials that are less than or equal in
emissions, to less than the HVLP or electrostatic spray application techniques.

NOTE:

Operate all application equipment according to the manufacturer's
specifications, company procedures or locally specified operating procedures.

(4) Paint Removal
(a) Paint removal operations apply to the outer surface of the airplane and do not apply to
parts or units normally removed. Fuselage, wings and stabilizers are covered. Parts that
are normally removed are exempt from the requirements that follow:
1
No organic hazardous air pollutants are to come from chemical strippers or softeners.
2
Inorganic hazardous air pollutant fumes must be kept to a minimum during periods
of non-chemical based equipment malfunctions.
3
The use of organic hazardous air pollutant material for spot stripping and decal
removal is kept to a minimum of 190 pounds per airplane per year.
(b) Operating requirements for paint removal operations that give airborne inorganic
hazardous air pollutants include control with particulate filters or water wash systems.
(c) Mechanical and hand sanding are exempt from these requirements.
8.

Facilities and Equipment
A.

Facilities
(1) A system must be supplied to collect processing waters to treat or remove chromium and pH.
(2) Facilities must have proper safety equipment.

B.

Equipment
(1) Applied spray of cleaning solvents, paint removers or color chemical film treatment solutions is
to be prevented unless all requirements of NESHAP are met.
© Cessna Aircraft

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(2)
(3)
(4)

Spraying equipment to wash the airplane with alkaline cleaner can be used. This equipment is
sufficient to spray deoxidizer, chemical film solutions and rinse water.
A high pressure washer is recommended, with or without hot water.
Respirators and/or dust masks must be used.

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MAINTENANCE MANUAL
TORQUE DATA

-

MAINTENANCE PRACTICES

General
A. To ensure security of installation and prevent over stressing of components during installation, the
torque values outlined in this section and other applicable chapters of this manual should be used
during installation and repair of components.
B. The torque value tables, listed in this section, are standard torque values for the nut and bolt
combinations shown. If a component requires special torque values, those values will be listed in the
applicable maintenance practices section.
C. Torque is typically applied and measured using a torque wrench. Different adapters, used in
conjunction with the torque wrench, may produce an actual torque to the nut or bolt which is different
from the torque reading. Figure 201 is provided to help calculate actual torque in relation to specific
adapters used with the torque wrench.
D. Free Running Torque Value.
(1) Free running torque value isthe torque value required to rotate a nut on a threaded shaft, without
tightening. Free running torque value does not represent the torque values listed in the tables
of this section. Torque values listed in the tables represent the torque values above free running
torque.
NOTE:

E.

EXAMPLE: If final torque required is to be 150 inch-pounds and the free running
torque is 25 inch-pounds, then the free running torque must be added to the required
torque to achieve final torque of 150 + 25 =1 75 inch-pounds.

(2) Breakaway torque value is the value of torque required to start a nut rotating on a thread shaft,
and does not represent free running torque value. It should be noted that on some installations
the breakaway torque value cannot be measured.
General Torquing Notes.
(1) These requirements do not apply to threaded parts used for adjustment, such as turnbuckles
and rod ends.
(2) Torque values shown are for clean, non lubricated parts. Threads should be free of dust, metal
filings, etc. Lubricants, other than that on the nut as purchased, should not be used on any bolt
installation unless specified.
(3) Assembly of threaded fasteners, such as bolts, screws and nuts, should conform to torque values
shown in Table 201.
(4) When necessary to tighten from the bolt head, increase maximum torque value by an amount
equal to shank friction. Measure shank friction with a torque wrench.
(5) Sheet metal screws should be tightened firmly, but not to a specific torque value.
(6) Countersunk washers used with close tolerance bolts must be installed correctly to ensure proper
torquing (refer to Figure 202).
(7) For Hi-Lok fasteners used with MS21 042 self-locking nuts, fastener and nut should be lubricated
prior to tightening.
(8) Tighten accessible nuts to torque values per Table 201. Screws attached to nutplates, or screws
with threads not listed in Table 201 should be tightened firmly, but not to a specific torque value.
Screws used with dimpled washers should not be drawn tight enough to eliminate the washer
crown.
(9) Table 201 is not applicable to bolts, nuts and screws used in control systems or installations
where the required torque would cause binding, or would interfere with proper operation of parts.
On these installations, the assembly should be firm but not binding.
(10) Castellated Nuts.
(a) Self-locking and non self-locking castellated nuts, except MS1 7826, require cotter pins and
should be tightened to the minimum torque value shown in Table 201. The torque may be
increased to install the cotter pin, but this increase must not exceed the alternate torque
values.
(b) M51 7826 self-locking, castellated nuts shall be torqued per Table 201.

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B212

NOTE:

SHORT OPEN END
ADAPTER

jg)

6_1

WHEN USING A TORQUE WRENCH ADAPTER WHICH
CHANGES THE DISTANCE FROM THE TORQUE WRENCH
DRIVE TO THE ADAPTER DRIVE, APPLY THE FOLLOWING FORMULAS TO OBTAIN THE CORRECTED TORQUE
READING.

TORQUE
WRENCH

WRENCH
DRIVE

HANDGRIP
CENTERLINE

D)

ADAPTER
DRIVE
CENTERLINE

SETSCREW
ADAPTER

FORMULA Tx L - Y
L+E

EXAMPLE (WITH "E" AS PLUS DIMENSION)
T
Y
E
L

HOSE CLAMP
ADAPTER

=
=
=
=

T =
Y =
L =
E=
OPEN-END WRENCH
ADAPTER

WRENCH
DRIVE
CENTERLI

Y_

135 IN-LB
UNKNOWN
1.5 IN
10.0 IN

Y

=

135x10 =117.39
10 + 1.5
117 IN-LB

LEGEND
ACTUAL (DESIRED) TORQUE
APPARENT (INDICATED) TORQUE
EFFECTIVE LENGTH LEVER
EFFECTIVE LENGTH OF EXTENSION

ADAPTER
DRIVE
CENTERLINE

HANDGRIP
CENTERLINE
U)

FLARE NUT WRENCH
ADAPTER

FORMULA

TORQUE
WRENCH

Tx L=
L- E

EXAMPLE (WITH "E" AS MINUS DIMENSION)

SPANNER WRENCH
ADAPTER

T
Y
L
E

=
=
=
=

135 IN-LB
UNKNOWN
10.0 IN
1.5 IN

Y_

135 x 10

10
Y

=

-

1.5

=

1350

=

158.82

8.5

159 IN-LB
5598T2005

Torque Wrench and Adapter Formulas
Figure 201 (Sheet 1)

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93213

EXTERNAL WRENCHING HEAD

CORRECT INSTALLATION
INSTALL WASHER WITH COUNTERSUNK
FACE NEXT TO BOLT HEAD RADIUS

INTERNAL WRENCHING HEAD

STAN DAR I
WASHER

COUNTERSUNK
WASHER
INCORRECT INSTALLATION

CAUTION:

NEVER INSTALL STANDARD
WASHER OR COUNTERSUNK
WASHER IN REVERSE WHEN
USING BOLTS WITH RADIUS
UNDER THE HEAD
5598T 1004
5598T1 004A

Washer Installation Close Tolerance Bolts
Figure 202 (Sheet 1)
0 Cessna Aircraft Company

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The end of the bolt or screw should extend through the nut at least two full threads including
the chamfer.
(11) Joints containing wood, plastics, rubber or rubberlike materials should be torqued to values
approximately 80 percent of the torque at which crushing is observed, or to the requirements of
Table 201, whichever is lower, or as specified.
(c)

2.

Torque Requirements for Bolts, Screws and Nuts
A. Use Table 201 to determine torque requirements for nuts, bolts and screws. Although the table makes
reference to nuts (because nuts are typically torqued), torque values are also applicable when applying
torque to bolts and screws.

Table 201. Torque Requirements For Steel Nuts, Bolts, and Screws (in Inch-Pounds)
FINE THREADED SERIES
(TENSION TYPE NUTS)

SIZE

FINE THREADED SERIES
(SHEAR TYPE NUTS
EXCEPT IVS1 7826)
Alternate
Standard
Torque
Torque

MS17826 NUTS

Standard
Torque

Alternate
Torque

12 to 19

12 to 15

12 to 20

30 to 40

30 to 48

30 to 40

30 to 45

lO00tolSO0

60 to 85

60 to 100

60 to 80

60 to 90

160 to 190

160 to 260

95 to 110

95 to 170

95 to 110

95 to 125

7/16-20

450 to 500

450 to 560

270 to 300

270 to 390

180 to 210

180 to 225

1/2-20

480 to 690

480 to 730

290 to41 0

290 to 500

240 to 280

240 to 300

9/16-18

800 to 1000

800 to 1070

480 to 600

480 to 750

320 to 370

320 to 400

5/8-18

1100 to 1300

llO
00tol1600

660 to 780

660 to 1060

480 to 550

480 to 600

3/4-16

2300 to 2500

2300 to 3350

1300 to 1500

1300 to 2200

880 to 101 0

880 to 1100

7/8-14

2500 to 3000

2500 to 4650

1500 to 1800

1500 to 2900

1500 to 1750

1500 to 1900

1-14

3700 to 4500

3700 to 6650

2200 to 3300

2200 to 4400

2200 to 2700

2200 to 3000

Standard
Torque

Alternate
Torque

8-36

12 to 15

--

10-32

20 to 25

20 to 28

12 to 15

1/4-28

50 to 70

50 to 75

5/16-24

100 to 140

3/8-24

~~7 to 9

NOTE 1: Fine Thread Tension application nuts include: AN310, AN315, AN345, MS17825, MS20365,
NASM21044 through MS211048, MS21 078, NAS679, NASi 291
NOTE 2: Fine Thread Shear application nuts include: AN316, AN320, MS21025, MS21042, MS21043,
MS21083, MS21245, NAS1022, S1117
NOTE 3: Coarse Thread application nuts include: AN340, MS20341, MS20365, MS35649
3.

Torque Requirements for Hi-Lolk Fasteners
Use Table 202 to determine torque requirements for Hi-Lok fasteners.
A.
NOTE:

This table is used in conjunction with MS21042 self-locking nuts.

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Table 202. Torque Values For Hi-Lok Fasteners (Alloy Steel, 180 to 200 ksi)
NOMINAL FASTENER DIAMETER

TORQUE VALUE (INCH-POUNDS)

6-32

8 to 10

8-32

12 to 15

10-32

20 to 25

1/4-28

50 to 70

5/16-24

100 to 140

3/8-24

160 to 190

7/16-20

450 to 500

1/2-20

480 to 690

4.

Torque Requirements for Electrical Current Carrying And Airframe Ground Fasteners
A. Use Table 203 to determine torque requirements for threaded electrical current carrying fasteners.
(1) Torque values shown are clean, non lubricated parts. Threads shall be free of dust and metal
filings. Lubricants, other than on the nut as purchased, shall not be used on any bolt installations
unless specified in the applicable chapters of this manual.
(2) All threaded electrical current carrying fasteners for relay terminals, shunt terminals, fuse limiter
mount block terminals and bus bar attaching hardware shall be torqued per Table 203.
NOTE:

B.

There is no satisfactory method of determining the torque previously applied to a
threaded fastener. When retorquing, always back off approximately 1/4 turn or more
before reapplying torque.
Use Table 204 to determine torque requirements for threaded fasteners used as airframe electrical
ground terminals.

Table 203. Torque Values For Electrical Current Carrying Fasteners
FASTENER DIAMETER

TORQUE VALUE (INCH-POUNDS)

6-32

8 to 12

8-32

13 to 17

10-32

20 to 30

3/16

20 to 30

1/4

40 to 60

5/16

80 to 100

3/8

105 to 125
130 to 1590

11/2

Table 204. Torque Values For Airframe Electrical Ground Terminals
FASTENER DIAMETER

TORQUE VALUE (INCH-POUNDS)

5/16

130 to 150

3/8

160 to 190

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5.

Torque Requirements for Rigid Tubing and Hoses
A. Use Table 205 to determine torque requirements for tubes and hoses.

Table 205. Tubing/Hose Torque Limits (Inch-Pounds)
Hose Size

I

Tubing O.D.

Flared or Flareless fitting
with Aluminum or Annealed
Stainless Steel Tubing, and
Hose with Aluminum Inserts

Flared or Flareless fitting with
Steel Tubing, and Hose with
Steel Inserts

Min

Max

Min

Max

-2

1/8

20

30

75

85

-3

3/16

25

35

95

105

-4

1/4

50

65

135

150

-5

5/16

70

90

170

200

-6

3/8

110

130

270

300

-8

1/2

230

260

450

500

-10

5/8

330

360

650

700

-12

3/4

460

500

900

1000

-16

1

500

700

1200

1400

-20

1 1/4

800

900

1520

1680

-24

1 1/2

800

900

1900

2100

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SAFETYING - MAINTENANCE PRACTICES

1.

General
A.

Safety Wire.
(1) Inconel (Uncoated), Monel (Uncoated).
(a) Inconel and Monel wires is used for general safety wire purposes. Safety wiring is used to
help prevent the movement of structural and other critical components. Monel safety wire
must be used at temperatures up to 700°F (371 C). Inconel saf ety wire must be used at
temperatures that get to 1500°F (815°C). The safety wire is i dentified by the color of the
wire. Monel and inconel color is a grey color.
(2) Copper, Cadmium-Plated and Dyed Yellow in accordance with FED-STD 595.
(a) The wires must be used for shear and seal wire applications. A shear application is when
it is necessary to break or shear the wire to let the emergency devices operate. A seal
application is when the wire is used with a lead seal to prevent tampering or the use of a
device without indication. The wires are identified by the color of the wire. Copper wire is
dyed a yellow color.
(3) Inconel and monel wires can be replaced with the same diameter and length of carbon steel or
corrosion resistant wire.
(4) Make sure you use the appropriate wire for the type of application.
NOTE:

B.

2.

Wires are visually identifiable by their colors. Grey color for inconel and monel, yellow
color for copper, and blue color for aluminum.

Cotter Pin.
(1) The selection of material must be in accordance with the temperature, atmosphere and service
limitations. Refer to Table 202.

Safety Wire
A.

Safety Wire Size.
(1) Refer to Table 201 for the required size of the safety wire.
(a) The 0.032 inch (0.80 mm) diameter safety wire is for general use. The 0.02 inch (0.51 mm)
diameter safety wire is acceptable to use.
(b) 0.02 inch (0.51 mm) diameter copper wire must be used for shear and seal wire applications
and can be used as follows:
1
For parts that have a nominal hole diameter of less than 0.045 inch (1.143 mm).
2
For parts that have a nominal hole diameter between 0.045 (1.143 mm) and 0.062
(1.574 mm) with space between the parts of less than 2.00 inches (51 mm).
3
For closely spaced screws and bolts of 0.25 inch (6.35 mm) diameter and smaller.
(c) The largest nominal size wire for the applicable material or part that the hole will
accommodate must be used when you use the single-wire procedure.

Table 201. Safety Wire
SIZE AND NUMBER (NASM20995-XXX)
Inches -

.015

.020

.032

.040

.041

.047

.051

.091

Millimeters-

0.30

0.51

0.80

1.00

1.04

1.19

1.30

2.31

NC20

NC32

NC40

NC51

NC91

Ni-Cr-Fe Alloy (Inconel)

N20

N32

N40

N51

N91

Carbon Steel

F20

F32

Material

Ni-Cu Alloy (Monel)

F41

F47

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Table 201. Safety Wire (continued)
SIZE AND NUMBER (NASM20995-XXX)
Inches -

.015

.020

.032

.040

.041

.047

.051

.091

Millimeters-

0.30

0.51

0.80

1.00

1.04

1.19

1.30

2.31

C15

C20

C32

C41

C47

C91

AB20

AB32

AB41

AB47

AB91

Material
Corrosion-Resistant
Steel
Aluminum Alloy (Blue)
Copper (Yellow)
3.

CY15

CY20

Safety Wire Installation
A.

Double-Twist and Single-Wire Procedures (Refer to Figure 201).
CAUTION: You must use the double-twist procedure of safety wiring with
screws that are In closely spaced geometric patterns that attach
hydraulic or air seals, hold hydraulic pressure, or are used In critical
areas.
(1) Use the double-twist safety wiring procedure as the common procedure of safety wiring.
(a) The double-twist procedure is one wire twisted on itself many times.
NOTE:

The single-wire procedure of safety wiring can be used in a closely spaced, closed
geometrical pattern (triangle, square, circle, etc.), on parts in electrical systems, and
in places that would make the single-wire procedure more advisable. Closely spaced
must be considered a maximum of two inches between centers.

(2) Safety wiring with the double-twist procedure must be done as follows:
(a) One end of the safety wire must be installed through one set of safety wire holes in the bolt
head.
(b) The opposite end of the safety wire must be looped firmly around the head to the next set
of safety wire holes in the same unit, and then inserted through the set of safety wire holes.
(c) The other end of the safety wire can go over the head when the clearances around the
head are obstructed by adjacent parts.
(d) With the wires tight, they must be twisted until the twisted part of the wire is just short of
the nearest safety wire hole in the next part. The twisted portion must be within 0.125
inch (3.175 mm) of the holes in each part. The twisting must keep the wire tight without it
stressed, kinked or mutilated.
NOTE:
(e)
(f)
(g)
(h)

The actual number of twists will depend upon the wire diameter, with smaller
diameters being able to have more twists than larger diameters.

The wire must be twisted to form a pigtail of 3 to 5 twists after you safety wire the last part.
Cut off any extra material at the end of the wire.
Bend the pigtail towards the part to prevent it from becoming a snag.
Safety wiring multiple groups by the double twist double hole procedure must be the same
as the previous double twist single hole procedure except the twist direction between
subsequent fasteners may be clockwise or counterclockwise.

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E
.

STEP 1. INSERT A WIRE THROUGH BOLT A AND BEND

BOLT A

IT1

A fll

kin

5TIf

II1 MnUIUMU I n

rIfl

5

r

k

r-,r~
'r

DUL I. Ir icLrtO,3n

A rfl\V

T,

BEND THE WIRE ACROSS THE BOLT HEAD.
TWIST THE WIRES CLOCKWISE UNTIL THEY
REACH BOLT B.
.INSERT ONE END OF THE WIRE THROUGH
BOLT B. BEND THE OTHER END AROUND THE
BOLT. IF NECESSARY, BEND THE WIRE ACROSS
THE BOLT HEAD. TWIST THE WIRES
COUNTERCLOCKWISE 0.50 INCH (12.70 mm)
OR SIX TWISTS. CLIP THE ENDS OF THE
WIRE AND BEND IT BACK AGAINST THE PART.
RIGHT THREADED PARTS SHOWN.
REVERSE DIRECTIONS FOR LEFT PARTS.

D
BOLT
B

IT

DOUBLE-WIRE SAFETYING

-

-COUNTERCLOCKWISE

MULTIPLE FASTENER
APPLICATION DOUBLE TWIST

DOUBLE-TWIST SAFETYING
0560MR025

Lockwire Safetying
Figure 201 (Sheet 1)

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E

EXTERNAL SNAP RING
SINGLE-WIRE METHOD

BOLTS IN CLOSELY SPACED, CLOSED
GEOMETRICAL PATTERN, SINGLE
WIRE METHOD

SINGLE FASTENER APPLICATION
DOUBLE-TWIST METHOD

SMALL SCREWS IN CLOSELY SPACED, CLOSED
GEOMETRICAL PATTERN, SINGLE WIRE METHOD

NOTE:

RIGHT THREADED
PARTS SHOWN. REVERSE
DIRECTION FOR LEFT
THREADS

5598T1003
5598T1024
5598T1024
5598T1024

Lockwire Safetying
Figure 201 (Sheet 2)

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B1680

0560R1026

Lockwire Safetying
Figure 201 (Sheet 3)

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(3) The single-wire procedure of safety wiring must use the largest nominal size wire listed in Table
201 that will fit the hole.
NOTE:

You can use the single-wire procedure in a closely spaced, closed geometrical pattern
(triangle, square, circle, etc.), on parts in electrical systems, and in places that would
make the single-wire procedure more applicable.

(a) Use the single-wire procedure for shear and seal wiring application.
(b) Make sure the wire is installed correctly so that it can be broken easily in an emergency
situation.
(c) Use only copper wire to attach emergency devices where it is necessary to break the wire
quickly.
B.

Safety Wire Space.
(1) When you use safety wire for widely spaced multiple groups of parts by the double-twist
procedure, three parts must be the maximum number in a series.
(2) When you use safety wire for close spaced multiple groups, the number of parts that can be
safety wired by a 24.00 inch (610.00 mm) length of wire must be the maximum number in a
series.
(3) Widely spaced multiple groups must mean those that the fastenings are from four to six inches
apart. Safety wiring must not be used to attach fasteners or fittings that are spaced more than
6.00 inches (152 mm) apart, unless tie points are given on adjacent parts to shorten the span of
the safety wire to less than 6.00 inches (152 mm).

C.

Tension.
(1) Parts must be safety wired so that the safety wire must be put in tension if the part loosens. The
safety wire must always be installed and twisted so that the loop around the head stays down
and does not come up and over the bolt head and leave a loop.
NOTE:

This does not necessarily apply to castellated nuts when the slot is close to the top
of the nut, the wire will be strongest if it is to pass along the side of the stud.

(2) Use care when you install safety wire to make sure that it is tight but not over stressed.
D.

Usage.
(1) A pigtail of 0.25 to 0.50 inch (6.35 to 12.70 mm), which is approximately 3 to 5 twists, must be
made at the end of the wiring.
(2) The pigtail must be bent back or under to prevent a snag.
(3) The safety wire must be new upon each application.
(4) When castellated nuts are to be attached with safety wire, tighten the nut to the low side of the
selected torque range, unless specified differently. If necessary, continue to tighten the nut until
a slot aligns with the hole.
(5) In blind tapped hole applications of bolts or castellated nuts on studs, the safety wiring must be
as described in these instructions.
(6) Hollow head bolts are safetied in the manner prescribed for regular bolts.
(7) Drain plugs and cocks can be safetied to a bolt, nut or other part having a free lock hole in
accordance with the instructions described in this text.
(8) External snap rings can be locked if necessary that follow with the general locking procedures.
Internal snap rings must not be safety wired. Refer to Figure 201.
(9) When safety wire is required on electrical connectors that use threaded coupling rings, or on
plugs that use screws or rings to attach the individual parts of the plug together, they must
be safety wired with 0.02 inch (0.51 mm) diameter wire in accordance with the safety wiring
procedures.
(a) You must safety wire all electrical connectors individually (not attach to each other), unless
it is not possible to do so.
(10) Drilled head bolts and screws need not be safety wired if installed into self-locking nuts or
installed with lock washers.
(11) Castellated nuts with cotter pins or safety wire is preferred on bolts or studs with drilled shanks.
Self-locking nuts are acceptable within the limitations of MS33588.

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(12) Larger assemblies such as hydraulic cylinder heads where safety wiring is required but not
specified, must be safety wired as described in these procedures.
(13) Safety wire must not be used to attach or be dependent on a fracture as the basis for the
operation of emergency devices such as handles, switches, guards covering handles, that
operate emergency mechanisms such as emergency exits, fire extinguishers, emergency cabin
pressure release, emergency landing gear release.
(14) Where existing structural equipment or safety of flight emergency devices require shear wire to
attach the equipment when not in use, but that are dependent upon shearing or breaking of the
safety wire for emergency operation of the equipment, particular care must be exercised to that
wiring under these circumstances and must not prevent emergency operations of these devices.
4.

Cotter Pin Installation
A.

General Selection and Application of Cotter Pins (Refer to Figure 202).

Table 202. Cotter Pin Application
Cotter Pins (MS24665)
Material

Temperature

Carbon Steel

Up to 450°F (232°C)

Pins that contact cadmium pl ated
surfaces, general applications
and non-corrosive environments.

Corrosion-Resistant

Up to 800°F (427°C)

Pins that contact
corrosion-resistant stell and
for corrosive environments.

(1)
(2)

(3)
(4)
(5)
(6)
(7)
(8)
5.

Use

The cotter pin must be new upon each application and the selection must be material in
accordance with temperature, atmosphere and service limitations. Refer to Table 201.
When the nuts are to be attached to the fastener with cotter pins, tighten the nut to the minimum
of the specified or selected torque range, unless otherwise specified. If necessary, continue to
tighten the nut until the slot aligns with the hole. The torgue must not be more than the maximum
torque range.
Castellated nuts that are mounted on bolts must be safetied with the preferred procedure of
cotter pins. Safety wire is a alternate procedure if cotter pins are not available.
In the event of more than 50 percent of the cotter pin diameter is above the nut castellation,
a washer must be used under the nut or a shorter fastener must be used. A maximum of two
washers can be permitted under a nut.
The largest nominal diameter cotter pin listed in MS24665, which the hole and slots will
accommodate must be used. The pin size must not be less than the sizes described in Figure
202 with application to a nut, bolt or screw.
Install the cotter pin with the head firmly in the slot of the nut with the axis of the eye at right angles
to the bolt shank and bend the prongs so that the head and upper prong are firmly seated against
the bolt.
In the pin applications, install the cotter pin with the axis of the eye parallel to the shank of the
clevis pin or rod end. Bend the prongs around the shank of the pin or rod end.
Cadmium plated cotter pins must not be used in applications that bring them in contact with fuel,
hydraulic fluid or synthetic lubricants.

Safetying Turnbuckles
A.

Use of Safety Wire.
(1) Some turnbuckles are attached with safety wire. The safetying procedures are detailed
and illustrated in Federal Publication AC 43-13.1B (or latest revision), Safety Methods For
Turnbuckles.

B.

Use of Locking Clips (Refer to Figure 203 and Table 203).

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I Table 203. Locking Clip Applications
Nominal Cable
Diameter

Thread UNF-3

Locking Clip MS21256
(Note 1)

Turnbuckle Body
MS21251

1/16

6-40

-1

-B2S

-2

-B2L

-1

-B3S

-2

-B3L

-1

-B5S

-2

-B5L

-1

-B5S

-2

-B5L

-1

-B6S

-2

-B6L

3/32

10-32

1/8

1/4-28

5/32

1/4-28

3/16

5/16-24

7/32

3/8-24

-2

-B8L

1/4

3/8-24

-2

-B8L

9/32

7/16-20

-3

-B9L

5/16

1/2-20

-3

-B10L

(1)
(2)

Before you use safety wire, each threaded terminal must be screwed an equal distance into the
turnbuckle barrel at a minimum not more than three threads of any terminal are shown outside
the body.
You must adjust the turnbuckle to the lock position with the groove on the terminals and slot
indicator notch on the barrel aligned. Insert the end of the locking clip into the terminal and
barrel until the "U" curved end of the locking clip is over the hole in the center of the barrel.
(a) Press the locking clip into the hole to its full extent.
(b) The curved end of the locking clip will latch in the hole in the barrel.

CAUTION: Do not use a tool since the locking clip can be twisted.
(c)

To check the correct seating of the locking clip, attempt to remove the pressed "U" end
from barrel hole with fingers only.

WARNING: Locking clips are for one-time use only.
(3)

Each locking clip can be installed in the same or opposite hole of the turnbuckle barrel.

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MAINTENANCE MANUAL

B1681

TO PROVIDE CLEARANCE
PRONG MAY BE CUT HERE

CASTELLATED NUT ON BOLT
ALTERNATE METHOD

CASTELLATED NUT ON BOLT
PREFERRED METHOD
TANGENT
TO PIN
MAXIMUM
COTTER PIN
LENGTH
DEGREES

DEGREES

'"""

MINIMUM

COTTER PIN
LENGTH

THREAD SIZE

MINIMUM
PIN SIZE
(INCH)

6

0.028

8

0.044

10

0.044

1/4

0.044

5/16

0.044

3/8

0.072

7/16

0.072

1/2

0.072

9/16

0.086

5/8

0.086

3/4

0.086

7/8

0.086

1

0.086

1 1/8

0.116

1 1/4

0.116

1 3/8

0.116

1 1/2

0.116

PIN APPLICATION
0560R1028

Cotter Pin Safetying
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL

B1682

STI RAIGHT END
HOOK SHOULDER

/

II

END LOOP

HOOK LIP

HOOK LOOP

QgL1

I IL
)

pi

~

2 ~)

,~~-c~-

)

1

T5L F^~ T(NOTE)
-fr
(NOTE)
BARREL

I I, ,z ,

, , , ,

<('' ' ',' '
E)

SABLE
TERMINAL

d
NOTE:

(NOTE)

PULL WITH YOUR FINGERS FOR AN
INSPECTION TO MAKE SURE THE CLIP
WILL NOT COME OUT.
0560R1023

Safetying Tumbuckle Assemblies
Figure 203 ISheet 1)

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MAINTENANCE MANUAL

B1683

TURNBUCKLE

LOCKING CLIP
MS21256

TURNBUCKLE EYE

CABLE

1 {
1

'1

THIMBLE
TURNBUCKLE BARREL
MS21251

l.-

I\

TYPICAL TURNBUCKLE ASSEMBLY

'
\
N\ \

\
'

\

\

\

\

\

\

,

'

\

LOCKING CLIP
MS21256

.11 I I

SWAGED
TERMINAL
METHOD OF ASSEMBLING LOCKING CLIPS, TURNBUCKLE BARREL AND TERMINALS

0560R1024

Safetying Turnbuckle Assemblies
Figure 203 (Sheet 2)

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MAINTENANCE MANUAL
SEALING - DESCRIPTION AND OPERATION
1.

General
A.

A list of the various sealants used throughout the airplane can be found in the Tools, Equipment and
Materials table of the effected chapters.

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MAINTENANCE MANUAL
ACCEPTABLE REPLACEMENTS FOR CHEMICALS AND SOLVENTS - DESCRIPTION AND OPERATION
1.

2.

General
A.

In response to the Aerospace National Emissions Standards for Hazardous Air Pollutants (NESHAP),
this data is being issued to inform customers of acceptable replacements for chemicals and solvents
in the Maintenance Manual that have been restricted or prohibited by the standards.

B.

For complete details of the regulatory standards, refer to Federal Register, 40 CFR Part 63 (Ad-FRL5636-1), RIN 2060-AG65.

C.

Compliance with the standard is mandatory by September 1, 1998.

Hand-Wipe Cleaning Operations
NOTE:

All hazardous air pollutants (HAP) or volatile organic compounds (VOC) hand-wipe cleaning
solvents must meet a composition requirement, have a vapor pressure less than or equal
to 45 MM Hg at 20@C, or meet the requirements speci fied in an alternative compliance plan
administered by the permitting authority and approved under Section 112 (1) of the Clean Air
Act.

Table 1. Replacement Products for Hand-Wipe Cleaning Operations
SURFACE

APPROVED PRODUCT/
NUMBER

SUPPLIER ADDRESS

All Metals and Painted Surfaces

Methyl n-propyl ketone (CAS No.
107-87-9)

Eastman Chemical Products
Wilcox Dr. And Lincoln St.
Kingsport, TN

Desoclean 110 (020K19)

Dynamold Solvents, Incorporated
2905 Shamrock Ave.
Fort Worth, TX 76107

All Plastics

Isopropyl Alcohol (TT-1-735)

Available Commercially

All Rubber (Natural or Synthetic)
and Silicone

Isopropyl Alcohol (TT-1-735)

Available Commercially

3.

Priming Operations
NOTE:

Priming operations may not exceed a maximum Hazardous Air Pollutant (HAP) limit of 2.9
lb./Gallon (350 Grams/Liter) (less water) per application. Priming operations may not exceed
a volatile organic compounds (VOC) limit of 2.9 lb./Gallon (350 Grams/Liter) (less water and
exempt solvents) per application. Compliance of this limit may be achieved through the use
of coatings which fall below content limits, or by using monthly volume-weighted averaging to
meet content limits.

Table 2. Replacement Products for Priming Operations
PRIMER APPLICATION

APPROVED PRODUCT/
NUMBER

SUPPLIER ADDRESS

Corrosion Primer (See Notes 1,4)

Corrosion Primer (513 X 419) (910
X 942)

Courtaulds Aerospace
1608 Fourth St.
Berkeley, CA 94710

Corrosion Primer (02-Y-40)
(02-4-40 CATA)

DEFT, Inc.
17451 Von Karman Ave.
Irvine, CA 92714

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MAINTENANCE MANUAL
Table 2. Replacement Products for Priming Operations (continued)
PRIMER APPLICATION

I

APPROVED PRODUCT/
NUMBER

SUPPLIER ADDRESS

Corrosion Primer
(U-1201F/U-1202F)

Sterling Lacquer Mfg.
3150 Brannon Ave.
St. Louis, MO 63139

Corrosion Primer
R4001-K14
MAX COR

U.S. Paint Corp.
831 S. 21st St.
St. Louis, MO 63103

Fuel Bay Primer (See Notes 2, 4)

Fuel Bay Primer 10P30-5

Dexter Crown Metro Aerospace
East Water St.
Waukegan, IL 60085

Pretreatment Primer (See Notes 3,
4)

Pretreatment Primer
(728-013/702-701)

Sherwin-Williams
630 E. 13th St.
Andover, KS 67002

NOTE 1:

Any primers which meet MIL-PRF-23377 requirements may be used.

NOTE 2:

This primer is restricted to the fuel bay area

NOTE 3:

Any pretreatment primers which meet DOD-P-15328 may be used.

NOTE 4:

4.

Specific application techniques must be used. If alternative is sought, it can only be used if
emissions are less than or equal to HVLP or electrostatic spray application techniques. All application
equipment must be operated according to manufacturer's specifications, company procedures, or
locally specified operating procedures.

Topcoat Operations
NOTE:

Topcoat operations may not exceed a maximum Hazardous Air Pollutant (HAP) limit of 3.5
lb./Gallon (420 Grams/Liter) (less water) per application. Topcoat operations may not exceed
a volatile organic compounds (VOC) limit of 3.5 lb./Gallon (420 Grams/Liter) (less water and
exempt solvents) per application. Compliance of this limit may be achieved through the use of
coatings which fall below content limits, or by using monthly volume-weighted averaging to meet
content limits. Topcoats which meet the requirements of MIL-C-85285 may also be used.

Table 3. Replacement Products for Topcoat Painting Operations
TOPCOAT APPLICATION

APPROVED PRODUCT/
NUMBER

SUPPLIER ADDRESS

Basecoat (See Note 4)

DeSothane 420HS Hisolids

Courtaulds Aerospace

I

Jet Glo High Solids System 810
Series

Sherwin-Williams
630 E. 13th St.
Andover, KS 67002

Low VOC Enamel

Sterling Lacquer Mfg.

I

24-F 20 Series

Dexter Crown Metro Aerospace

Low VOC Acrylic 830 Series

Sherwin-Williams
630 E. 13th St.
Andover, KS 67002

Paint Stripes (See Note 4)

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MAINTENANCE MANUAL

5.

Paint Stripping Operations
NOTE:

Unless exempted, no organic Hazardous Air Pollutant (HAP) are to be emitted from chemical
strippers or solvents. Use of organic HAP materials for spot stripping and decal removal is limited
to 190 pounds per airplane per year.

Table 4. Replacement Products for Paint Stripping Operations
APPLICATION

APPROVED PRODUCT/
NUMBER

SUPPLIER ADDRESS

Chemical Stripping

Turco T-6776 LO

Turco Products, Inc.
Westminster, CA 92684

Mechanical Stripping (See Note 5)

180 Grit or finer

Available Commercially

NOTE 1: Mechanical and hand-sanding operations are exempt from these requirements

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MODEL 172
MAINTENANCE MANUAL
GENERAL SOLVENTS/CLEANERS - MAINTENANCE PRACTICES
1.

General
A.

2.

Solvents are used in a wide range of cleaning activities and selected solvents can be used in the
removal of oil, grease and dirt from objects without harm to metal, plastics or elastomeric parts.

Tools, Equipment and Materials
NOTE:

The following items are used in conjunction with various solvents to aid in cleaning parts and
components.

NAME

NUMBER

Detergent

MANUFACTURER

USE

Commercially available

General cleaning.

ScotchBrite Pads

Type A

Minnesota Mining and Mfg. Co.
3M Center
St. Paul, MN 55101

Light abrasion of metal
surfaces.

Sandpaper

320 Grit

Commercially available

Light abrasion of metal
surfaces.

Rymple Cloth

Commercially available

Wiping and applying
cleaning agents.

Wiping cloth white,
oil free, absorbent

Commercially available

Wiping and applying
cleaning agents.

3.

4.

Safety Precautions
A.

Solvents are composed of a group of chemicals that often prove toxic. Anyone engaged in
maintenance, repair and operation of airplane and airplane accessories may be exposed to these
chemicals.

B.

To help avoid the effects of these toxic substances, work only a clean, well-lighted and well-ventilated
area. Rubber gloves and protective clothing should be worn. Avoid breathing spray vapors as they
are highly toxic.

C.

When working with toxic substances, always be alert for symptoms of poisoning. If symptoms are
observed, immediate removal of the victim from the contaminated area is most important.

Description
A.

Solvents exhibit a selective solvent action which permits its use in the removal of oil, grease or dirt. For
selection of proper solvent, refer to Table 201. For the cleaning of metal, plastics or rubber, proceed
as follows:
(1) Metal.
NOTE:
(a)
(b)
(c)
(d)
(e)

Prior to bonding or priming, lightly abrade surface with either a ScotchBrite pad or
sandpaper prior to cleaning.

Wipe off all excess oil, grease or dirt from surface.
Apply solvent to a clean cloth by pouring solvent on the cloth from a safety can or other
approved container. The cloth should be well saturated but not to the point of dripping.
Wipe the surface with the moistened cloth as required to dissolve or loosen soil. Work on
small enough area so the surface being cleaned remains wet.
With a clean dry cloth, immediately wipe the surface while the solvent is still wet. Do not
allow the surface to evaporate dry.
Repeat steps (b) through (d) until there is no discoloration on the drying cloth.

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MODEL 172
MAINTENANCE MANUAL
(2)

Plastic or Rubber.
NOTE:
(a)
(b)
(c)
(d)
(e)

If cleaning a bonding surface, lightly abrade the bonding surface with sandpaper prior
to cleaning.

Remove heavy soil from surface by washing with a water detergent solution.
Apply solvent to a clean cloth by pouring solvent onto cloth from a safety can or other
approved container. The cloth should be well saturated but not to the point where dripping.
Wipe the surface with the moistened cloth as required to dissolve or loosen soil. Work on
a small enough area so that the surface being clean remains wet.
Using a clean dry cloth, immediately wipe the surface while the surface is still wet. Do not
allow the surface to evaporate dry.
Repeat steps (b) through (d) until there is no discoloration on the drying cloth.

Table 201. General Solvents
CLEANER/
SOLVENT

FEDERAL
SPECIFICATION

TYPE
CLASSIFICATION

Dry

MILPFR-680

Type I -100°F General cleaning solvent.
Typell-140°F Dry cleaning of textile
materials. Grease
removal.

FLAMMABLE.

Type
I
Regular
Type II - with
dauber
III
Type
Aerosol

USE WITH ADEQUATE
VENTILATION.
AVOID PROLONGED
BREATHING OF VAPOR.
AVOID PROLONGED
CONTACT WITH SKIN.

1,1,1
O- T-620
Inhibited
Technical
Trichloroethane

USE/ DESCRIPTION
FUNCTION

Spot removing from
fabrics. General cleaning
solvent. Cleaning of
assembled equipment.

CAUTION/ WARNING

Turco Seal
Solvent Turco
Products

Cleaning/Degreasing
metal parts.

Penwalt 2331

Preparing metal plate for
painting.

ACID ACTIVATED
SOLVENT, DO NOT
USE ON PLASTICS.

Use in soak tank
tofacilitate removal of
carbon, gum, oil and other
surface contaminants
except rust or corrosion
from engine and other
metal parts.

REMOVES PAINT. AVOID
CONTACT WITH SKIN.

Carbon
Removing
Compound

P-C-

Cleaning
Compound

P-C-535

Cleaning
Compound,
Unfinished
Aluminum

MIL-C5410

111A

Heavy duty electro
cleaner used for removal
of soils from ferrous
metal surfaces prior to
electroplating or other
treatments.
Type I Viscous
Emulsion

Used full strength for
overhaul of unfinished
aluminum surfaces.

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MAINTENANCE MANUAL
Table 201. General Solvents (continued)
CLEANER/
SOLVENT

FEDERAL
SPECIFICATION

TYPE
CLASSIFICATION

USE/ DESCRIPTION
FUNCTION

Type II -Clear
Liquid

Use full strength or diluted
with mineral spirits and
water for maintenance
of airplane unfinished
aluminum surfaces.

CAUTION/ WARNING

Trichloroethylene

O-T634B

Type
I
-Regular
Type II-Vapor
Degreasing

Cleaning of metal parts.
Degreasing of metal parts.
Special purpose solvent.

REMOVES PAINT
AND DAMAGES
PLASTICS. USE ONLY
WITH ADEQUATE
VENTILATION. HIGH
CONCENTRATIONS
OF VAPOR ARE
ANESTHETIC AND
DANGEROUS TO LIFE.
VERY TOXIC.

Polish, Metal
Aluminum

MILP-6888C

Type I -Liquid
Type IIPaste

Metal polish for use
on airplane aluminum
surfaces.

FLAMMABLE.

Naphtha,
Aliphatic

TT-N958

Type I

For use with organic
coatings only.

DO NOT USE WITH
ACRYLIC
PLASTICS.
FLAMMABLE

Type II

Cleaner for acrylic plastics
and may be used in
placeof Type I General
cleaningagent.

VAPOR
HARMFUL.
AVOID PROLONGED OR
REPEATED BREATHING
OR CONTACT
WITH
SKIN.

Paint and adhesive
thinner, cleaning agent.

FLAMMABLE.

For use with organic
coatings and as an
anti-icing fluid. General
Solvent for synthetic
rubbers.

USE DISCRIMINATELY
WITH ACRYLIC
PLASTICS.

A waterproof wax that can
be dissolved or dispersed
with an organic solvent.

DO NOT USE SOLVENTS
THAT MAY DAMAGE
PAINT OR FINISH FOR
REMOVAL OF WAX.

Methyl Ethyl
Ketone

TT-M261D

Isopropyl
Alcohol

TT-I-735

Wax,
Airplane,
Waterproof
Solvent Type

MIL-W18723C

Grade B
-0.4% water

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MODEL 172
MAINTENANCE MANUAL
Table 201. General Solvents (continued)
CLEANER/
SOLVENT

FEDERAL
SPECIFICATION

TYPE
CLASSIFICATION

USE/ DESCRIPTION
FUNCTION

CAUTION/ WARNING

Cleaning Compound,Aluminum

MIL-C5410B

Type I
-Viscous
Emulsion

Use full strength for
maintenance of unfinished
aluminum surfaces.

Type II - Clear
Liquid

Use full strength or diluted
with mineral spirits and
water for maintenance
of unfinished aluminum
surfaces.

RUBBER OR
SYNTHETIC RUBBER
GLOVES AND EYE
PROTECTIONSHOULD
BE USED WHEN
HANDLING THE
COMPOUND.
WASH FROM SKIN
IMMEDIATELY WITH
WATER OR A
SOLUTION OF SODIUM
BICARBO-NATE AND
APPLY GLYCERIN OR
PETROLEUM JELLY.
WASH FROM EYES AS
PER MANUFACTURER'S
INSTRUCTIONS AND
REPORT TO NEAREST
MEDICAL FACILITY.

Toluene

A-A59107D

Use as a solvent or thinner
for organic coatings,
various resins, and
chlorinated rubber. Also
used to dilute cellulose
lacquers and dopes.

FLAMMABLE VAPOR.
VAPOR HARMFUL.

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MAINTENANCE MANUAL
INTERIOR AND EXTERIOR FINISH - CLEANING/PAINTING
1.

General
A.

2.

Interior and exterior finish cleaning/painting consists of general information and instructions for
applying chemical film treatments, primer and topcoats to the airplane.

Interior and Exterior Finishes
A.

Detail aluminum parts are chemically pretreated and epoxy primed prior to assembly. The chem-film
pretreatment and the epoxy primer are primary coatings and must be maintained and preserved for
corrosion control. Exterior assemblies that are to be topcoated receive ScotchBrite, hand solvent
cleaning and another overall application of epoxy primer. The airplane exterior then receives an
overall topcoat of polyurethane paint.

CAUTION: ALL PLASTIC AND FIBERGLASS PARTS, EXCEPT BUS-INGS,
BEARINGS, GROMMETS AND CERTAIN PURCHASED ANTENNA
COVERS WHICH ARE NOT COLORED OR PAINTED, SHALL
BE COLORED OR PAINTED TO MATCH ADJACENT SURFACE.
THE HEAD OF THE PITOT TUBE MUST BE OPEN AND FREE
FROM PAINT AND OTHER FOREIGN OBJECTS. THE SURFACE
ADJACENT TO STATIC PORT MUST BE SMOOTH AND FREE
FROM ALL PAINT IMPERFECTION. DO NOT PAINT PITOT TUBE,
FUEL CAPS, TRIM TAB PUSHRODS WHERE THEY OPERATE IN
AN ACTUATOR, OLEO STRUT SLIDING SURFACES, STANDARD
POLISHED SPINNERS, EXHAUSTS, STALL WARNING VANES,
CHROMED ITEMS (HANDLES, LOCKS, ETC.) OR THE TIE-DOWN
LUGS (LOCATED ON STRUTS) OR LIGHT LENS. PAINT THE
LANDING GEAR BARRELS AND TORQUE LINKS TO MATCH THE
OVERALL COLOR.
3.

Paint Facility
A.

4.

Painting facilities must include the ability to maintain environmental control of temperature at a
minimum of 65°F (18°C). All paint equipment must be clean. Ac curate measuring containers should
be available for mixing protective coatings. Use of approved respirators while painting is a must
for personal safety. All solvent containers should be grounded to prevent static buildup. Catalyst
materials are toxic, therefore, breathing fumes or allowing contact with skin can cause serious
irritation. Material stock should be rotated to allow use of older materials first, because its useful life
is limited. All supplies should be stored in an area where temperature is higher than 50°F (10C), but
lower than 90°F (32°C). Storage at 90°F (32°C) is allowable f or no more than sixty days, providing it
is returned to room temperature for mixing and use.
(1) Areas in which cleaning or painting are done shall have adequate ventilation and shall be
protected from uncontrolled spray, dust, or fumes.
(2) Areas for prolonged storage of cleaned parts and assemblies awaiting painting shall be free from
uncontrolled spray, dust, or fumes, or else positive means of protecting part cleanliness such as
enclosed bins or wrapping in kraft paper shall be provided.
(3) Areas in which cleaning or painting are done shall be periodically cleaned and dusted.
(4) Compressed air used for dusting and paint spraying shall be free from oil, water and particulate
matter.

Sanding Surfacer
A.

Purpose and Requirements.
(1) Surfacer is applied over fiberglass and ABS assemblies to provide aerodynamic contour,
smoothness and to seal porous surfaces. Application of surfacer also provides a good surface
for a polyurethane finish.

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MAINTENANCE MANUAL
(2) The objective of a surfacer is to fill local depressions, pits, pin holes and other small surface
defects so a smooth surface is obtained for paint. The total surfacer thickness shall not be
greater than 15 mils (0.38 mm). Only enough surfacer shall be applied to obtain a smooth
surface for paint. If less thickness will provide a smooth surface, this is better. A thick layer of
surfacer is less flexible and may crack in service.
(3) To complete the airplane's polyurethane finish over surfacer, begin by applying the intermediate
coat. Apply topcoat (polyurethane enamel) using same procedure.
(4) Should a repair be required (cracked or chipped paint) to areas where surfacer is applied,
sanding surfacer should be removed to expose fiberglass or Kevlar. It may be necessary
to remove all sanding surfacer on that individual assembly and/or component to obtain a
satisfactory finish. For additional information, refer to Cleaning.
(5) Sanding surfacer methods.
(a) Do not intermix vendor material or substitute material. Also, do not substitute instructions.
Select and use one vendor's material and use the corresponding instructions.
B.

Cleaning.

CAUTION: DO NOT USE CHEMICAL STRIPPERS ON ABS PLASTIC AND
FIBERGLASS ASSEMBLIES. PAINT STRIPPER SOLVENT WILL
DAMAGE THESE ASSEMBLIES.
CAUTION: SANDING OF PAINT AND/OR SANDING SURFACER MUST BE VERY
CAREFULLY ACCOMPLISHED. DO NOT SAND INTO THE FABRIC
LAYERS OF COMPOSITE ASSEMBLIES AS THIS WILL RESULT IN
LOSS OF STRENGTH.
(1)
(2)
(3)
(4)
5.

Remove paint covering sanding surfacer by sanding. Paint should be removed well beyond
damaged area. For best results, it is recommended to remove all paint covering sanding surfacer
of that individual composite component.
Remove sanding surfacer by sanding from individual component to expose fabric.
Scuff sand area to be refinished with 320 grit paper. Do not over expose fabric.
Clean surface with Methyl n-Propyl Ketone. Follow manufacturer's instructions for final cleaning
prior to sanding surfacer application.

Paint Stripping
A.

Mechanical Stripping
(1) Mechanical methods of stripping include power sanding with a disc or jitterbug type sander,
grinder, hand sanding, and wire brushing.
(a) Ensure mechanical methods do not damage surfaces being stripped. Damage may
include, but is not limited to, cutting fibers of composite structures or scratches in the
surface of metallic surfaces.

CAUTION: DO NOT USE LOW CARBON STEEL BRUSHES ON
ALUMINUM, MAGNESIUM, COPPER, STAINLESS STEEL
OR TITANIUM SURFACES. STEEL PARTICLES MAY
BECOME EMBEDDED IN THE SURFACES, AND LATER
RUST OR CAUSE GALVANIC CORROSION OF THE METAL
SURFACES.
(2)
(3)
(4)
B.

Mechanical stripping must be used for stripping composite or plastic surfaces.
Mechanical stripping is recommended for surfaces which might entrap chemical strippers and
result in corrosion.
Mechanical stripping is required for painted surfaces masked during chemical stripping.

Chemical Stripping.

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MAINTENANCE MANUAL
WARNING: ALL PAINT STRIPPERS ARE HARMFUL TO EYES AND SKIN.
ALL OPERATORS SHOULD WEAR GOGGLE-TYPE EYEGLASSES,
RUBBER GLOVES, APRONS AND BOOTS. IN CASE OF CONTACT
WITH SKIN, FLUSH WITH WATER. IN CASE OF CONTACT WITH
EYES, FLUSH EYES THOROUGHLY WITH WATER AND CONSULT
PHYSICIAN IMMEDIATELY. PAINT STRIPPING SHOULD BE DONE
IN A WELL VENTILATED AREA.
WARNING: USE OF A HEATER WITH AN OPEN FLAME IN AN AREA IN WHICH
STRIPPING WITH A METHYLENE CHLORIDE TYPE STRIPPER
IS USED PRODUCES HYDROCHLORIC ACID FUMES. IF ACID IS
DEPOSITED ON AIRPLANE IT WILL CORRODE ALL SURFACES.
(1) Thoroughly clean airplane surfaces to remove all grease and other dirt which might keep
stripping agent from attacking paint.
(2) All seams and joints must be protected by applying a tape, resistant to strippers, to every
joint to prevent stripping chemicals from entering the skin joints. Chemicals used for stripping
polyurethane paint are very difficult to remove from joints, and may promote corrosion or
deteriorate bonding agents used in assembly of airplane.
(3) Mask following surfaces using plastic sheeting or waxed paper and plastic tape so as to make
a safety margin of at least one-half inch (13 mm) between protected surface and surface to be
stripped.
NOTE:

Do not use masking tape.

(a) Mask all windows and transparencies.

CAUTION: ACRYLIC WINDOWS MAY BE SOFTENED OR OTHERWISE
DAMAGED BY PAINT STRIPPER, SOLVENT OR PAINT. USE
WATER AND GREASE-PROOF BARRIER MATERIAL AND
POLYETHYLENE COATED TAPE TO PROTECT WINDOWS.
1

(b)
(c)
(d)
(e)
(f)
(g)

Place barrier material over window and seal around periphery with polyethylene
backed masking tape.
2
Cut second sheet of barrier material an inch (26 mm) or more larger than window.
3
Place second sheet of barrier material over window and seal with polyethylene tape.
Mask all rubber and other non metals.
Composites if possible, shall be removed from airplane prior to stripping.
Mask all honeycomb panels and all fasteners which penetrate honeycomb panels.
Mask all pivots, bearings and landing gear.
Titanium, if used on airplane, must be protected from strippers.
Mask all skin laps, inspection holes, drain holes, or any opening that would allow stripper
to enter airplane structure.

CAUTION: DO NOT ALLOW PAINT STRIPPER TO CONTACT
HEAT TREATED STEEL PINS, SUCH AS PINS ATTACI-IING
LANDING GEAR COMPONENTS. PAINT STRIPPERS MAY
INDUCE HYDROGEN EMBRITTLEMENT
HIGH HEAT
IN
TREATED STEEL.
(4) Apply approved stripper by spray or brush method.

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WARNING: USE NORMAL SAFETY PRECAUTIONS
WHEN
USING
FLAMMABLE MATERIALS DURING CLEANING AND PAINTING
PROCEDURES.

WARNING: PAINT STRIPPER SOLUTION IS HARMFUL TO EYES AND SKIN.
WEAR GOGGLES, RUBBER GLOVES, APRON AND BOOTS
WHEN WORKING WITH PAINT STRIPPER. ALSO WEAR
APPROPRIATE RESPIRATOR WHEN APPLYING "SPRAY-ON"
STRIPPERS. THE CHEMICAL SUPPLIER BULLETINS AND
INSTRUCTIONS SHOULD BE CLOSELY FOLLOWED FOR
PROPER MIXING OF SOLUTION, APPILICATION METHODS
AND SAFETY PRECAUTIONS.

(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
C.

(a) If using spray method, apply a mist coat to area to be stripped, then when paint begins to
lift, apply a second heavy coat.
(b) If applying with brush, brush across the surface only once, in one direction.
Allow stripper coating to lay on the surface until paint lifts.
After paint begins to lift, use a propylene bristle brush to agitate stripper to allow deeper
penetration of stripper.
Remove lifted paint with a plastic squeegee. Dispose of residue in accordance with local
regulations.
Inspect all surfaces for incomplete paint removal.
(a) Repeat previous procedural steps as necessary until all paint is removed.
After stripping airplane, thoroughly rinse to remove any stripping residue.
Remove tape applied to protect joints and other masked areas.
Carefully remove remaining paint at skin joints and masked areas by sanding with a hand or
jitterbug type sander.
If necessary to remove paint from inside skin joints, refer to Cleanout of Skin Joints.
If corrosion is encountered, refer to Structural Repair Manual, Chapter 51, Corrosion/Repair, for
corrosion treatment.

Cleanout of Skin Joints.
(1) Install a surface conditioning disc on a pneumatic drill.
(2) Taper edge of disc to an edge which will allow edge to fit into skin joint seam.
(a) Run disc against a piece of coarse abrasive paper or a mill file until edge is tapered.

CAUTION: EXCESSIVE PRESSURE OR DWELL TIME WILL CAUSE
SCRATCHES OR GROOVES INMETAL. ENSURE DOUBLER
AT BOTTOM OF JOINT IS NOT DAMAGED OR GOUGED IN
ANY WAY BY THIS PROCESS.
(3) Using tapered surface conditioning disc, remove paint and other material from joint seams.
(4) Carefully, and using as low speed as possible, remove paint and all other material from joint.
NOTE:

Surface conditioning disc will wear rapidly, it will be necessary to resharpen (retaper)
disc frequently.

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6.

Hand Solvent Cleaning

WARNING: WORK IN A WELL VENTILATED AREA FREE FROM SOURCES OF
IGNITION. USE ONLY APPROVED SOLVENTS AND MATERIALS.
CAUTION: AIRPLANE SHALL BE GROUNDED DURING SOLVENT WIPE.
A.

7.

Surface Cleaning.
(1) Apply solvent to a clean wiping cloth by pouring from a safety can or other approved container.
The cloth should be well saturated with solvent. Avoid dipping wipers into open solvent
containers as this contaminates the solvent.
(2) Wipe the surface with the wet cloth as required to dissolve or loosen soils. Work on a small
enough area so that the area being cleaned remains wet with solvent.
(3) With a clean dry cloth, immediately wipe dry the area being cleaned. Do not allow the surface
to evaporate dry.
(4) Repeat steps (1) through (3) as required and change cloths often.

Maintenance of the Interior and Exterior Primary Coatings and Topcoat
A.

Rework and repair primary coatings on airplane interior and exterior surfaces for protection and
corrosion control.
(1) Minor scratches or defects, which do not penetrate the epoxy primer or which penetrate the
primer and expose bare metal, with the total area of exposed bare metal less than the size of a
dime, touch up as follows:
(a) Hand solvent clean and sand with 320 grit or finer sandpaper.
(b) Clean with compressed air, hand solvent clean again, then wipe with a tack rag.
(c) Mix and reapply epoxy primer (MIL P-23377 or equivalent) as directed by the primer
manufacturer or supplier.
(d) On a properly prepared surface, mix and apply polyurethane topcoat as directed by the
paint manufacturer or supplier.
(2) Major defects which expose bare metal to an area larger than the size of a dime, touch up as
follows:
(a) Hand solvent clean and sand with 320 grit or finer sandpaper.
(b) Clean with compressed air, hand solvent clean again, then wipe with a tack rag.
(c) Apply a spray wash primer or (preferred method) brush chem film primer. Mask the area
to minimize the amount of primer from spreading over the existing epoxy primer. Let cure
according to the product manufacturers recommendations.
(d) Mix and apply epoxy primer (MIL P-23377 or equivalent) to the affected area within four
hours.
(e) If an exterior painted surface, mix and apply polyurethane topcoat as directed by the paint
manufacturer or supplier.

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FUEL, WEATHER AND HIGH-TEMPERATURE SEALING - MAINTENANCE PRACTICES
1.

General
A.

2.

Procedures for application of sealants are provided for various types of sealing required for the
airplane.

Tools and Equipment
NOTE:

Specified sealants, cleaning solvents, parting agents, adhesion inhibitors and equipment are
listed for use. Suitable substitutes may be used for sealing equipment only.

Table 201. Sealants Type I, Class A-1/2, or A-2-AMS-S-8802

NAME

NUMBER

MANUFACTURER

USE

Sealants

GC-408

Goal Chemical Sealant Corp.
3137 East 26th Street
Los Angeles, CA 90023

Fuel, pressure and
weather sealant brush
application.

Pro-Seal 890

PRC-DeSoto International
5454 San Fernando Rd.
Glendale, CA 91209

PR-1440

PRC-DeSoto International

Table 202. Sealants Type I, Class B-1/4, Quick Repair-MIL-S-83318

Sealant

GC-435

Goal Chemical Sealant Corp.

Fuel, pressure and
weather sealant. For
limited repairs requiring
rapid curing sealant.

Table 203. Sealants Type I, Class B-1/2, B-2 or B-4-AMS-S-8802

NAME

NUMBER

MANUFACTURER

USE

Sealants

PR-1440

PRC-DeSoto International

Fuel pressure and
weather sealant,
suitable for application
by extrusion gun and
spatula.

AC-236

Advanced Chemistry And
Technology

CS 3204

Flamemaster Corporation

Pro Seal 890

PRC-DeSoto International

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Table 204. Sealants Type I, Class C-20, C-48 or C-80

Sealant

Pro-Seal 890

PRC-DeSoto International

Fuel, pressure and
weather sealant. Suitable
for faying surface sealing.

Dapco 2100

D. Aircraft Inc.
Anaheim, CA 92807

Firewall and wire bundle
sealing.

Pro Seal 700

PRC-DeSoto International

Firewall sealing (except
wire bundles).

Q3-6077

Dow Corning

Wire bundle firewall
sealing.

Table 205. Sealants Type IV

Sealant

Table 206. Sealant Type VI

I

Sealant

FA-0606 125

HB Fuller
St. Paul, MN 55116

Water and weather-tight
acrylic latex sealant for
windows and metal lap
joints.

Sealant

SM8500

Schnee-Moorehead
Irving, TX 75017

Water and weather-tight
acrylic latex sealant for
windows and metal lap
joints.

Table 207. Sealant Type VIII, Class B-1/2 or B-2-MIL-S-8784

Sealant

PR-1428 Class

PRC-DeSoto International

PR-1081 Class

PRC-DeSoto International

Low adhesion access
door, fuel, pressure and
weather sealing.

Table 208. Sealant Type Xl

Sealant

U000927S

Available from
Cessna Parts Distribution
Cessna Aircraft Company
Department 701
5800 E. Pawnee Rd.
Wichita, KS 67218-5590

Permanently pliable
extruded tape for fixed
windows.

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Table 209. Cleaning Solvents

NAME

NUMBER

MANUFACTURER

USE

1, 1, 1 Trichloroethane
Technical
Inhibited (Methyl
Chloroform)

Federal
Specification
ASTM D4126

Commercially Available

Presealing cleaning.

Commercially Available

Cleaning organic coating.

Methyl Propyl
Ketone
Naphtha Type II

Federal
Specification
TT-N-95

Commercially Available

Presealing cleaning.

Cleaning
compound

A-A-59281

Commercially Available

Presealing cleaning.

Isopropyl alcohol

Federal
Specification
TT-I-735

Commercially Available

Cleaning plastic (Except
plastic transparencies).

Table 210. Parting Agents

NAME

NUMBER

MANUFACTURER

USE

Silicone compounc

AS 8660

Commercially available

Prevent sealant sticking.

Petrolatum
technical

Federal
Specification
VV-P-236

Commercially available

Prevent sealant sticking.

Pneumatic sealing
gun.

Semco
Number
250 with
accessories
(or equivalent)

PRC DeSoto International

Injection sealing.

Hand-operated
sealing gun

Semco
Number 850

PRC DeSoto International

Injection sealing.

PRC DeSoto International

Application of sealant.

Table 211. Equipment

Nozzles,
Round 1/16 orifice

Semco
420

No.

Round 1/8 orifice

Semco
440

No.

Duckbill

Semco
8615

No.

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Table 211. Equipment (continued)
Duckbill

Semco
8648

No.

Comb

Semco
8646

No.

Polyethylene
cartridges with
plungers and caps
for sealant gun.

Commercially available

Application of sealant.

Metal spatulas with
either stainless
steel or glass
plates.

Commercially available

Mixing sealant.

Plastic lined cups,
wax-free with caps

Commercially available

Mixing sealant.

Sealant fairing
tools

Commercially available

To fair in sealant.

Cheesecloth,
lint-free

Commercially available

Cleaning.

Plastic scraper,
45-degree cutting
edge.

Commercially available

Removing old sealant.

Rex Gauge Company, Inc.
3230 West Lake Avenue
P.O. Box 46
Glenview, IL 60025

Testing cure of sealant.

Gloves, lightweight
lint-free white
cotton

Commercially available

Removing old sealant.

Nylon bristle
brushes

Commercially available

Removing old sealant.

Pipe cleaners

Commercially available

Cleaning.

Funnel brushes

Commercially available

Cleaning.

Durometer

3.

Rex Model
1500 (or
equivalent)

Definition of Sealing Terms
A.

The following definitions are included to provide a basic concept of the special terms used in sealing.
This list is not all-inclusive but the more common terms are listed.
(1) Absolute Sealing - There can be no leakage allowed. All openings of any nature through the seal
plane are positively sealed. This is the first level of sealing. (All holes, slots, joggles, fasteners
and seams must be sealed.)
(2) Accelerator (Activator) - Curing agent for sealants.
(3) Application Time - The length of time sealant remains workable or suitable for application to
structure by brush, extrusion gun, spatula or roller.
(4) Base Compound - The major component of a two-part sealing compound which is mixed with the
accelerator prior to application to produce a fuel, temperature, pressure, weather and/or firewall
sealing material.
(5) Brush Coat - Apply an overcoat or continuous film of appropriate sealing compound by use of a
brush.

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(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)

(15)
(16)
(17)
(18)

(19)
(20)

4.

Fay Seal or Faying Surface Seal - A seal barrier created by the sandwiching of sealant between
mating surfaces of structure. Special attention must be taken to avoid metal chips or dirt at the
faying surface.
Fillet Seal - Sealant material applied at the seam, joint or fastener after the assembly has all
permanent fasteners installed and shall conform to the dimension in applicable figure.
Hole - An opening that has no appreciable depth, such as a tool hole. Holes that penetrate the
seal plane must be metal filled with a fastener, gusset or patch.
Injection Seal - Filling of channels by forcing sealant into a void or cavity after assembly.
Integral Tank - Composition of structure and sealant material which forms a tank that is capable
of containing fuel without a bladder.
Intermediate Seal - The second level of sealing. All holes, slots, joggles and seams in the seal
plane must be sealed. A minor amount of leakage is tolerable and permanent fasteners are not
required to be sealed.
Post-Assembly Seal - A seal that is applied after the structure is assembled. (Fillet and injection
seals.)
Preassembly Seal - Sealant material that must be applied during or prior to the assembly of the
structure. (Faying surface and pre-pack seals.)
Pre-Pack Seal - A preassembly seal used to fill voids and cavities; can be a primary seal used
to provide seal continuity when used in conjunction with a fillet seal. It can be used as a backup
seal to support a fillet across a void. Fill the entire cavity to be prepacked. Usage as a primary
seal should be kept to a minimum.
Primary Seal - Sealant material that prevents leakage and forms a continuous seal plane. This
seal is in direct contact with fuel, vapor, air, acid, etc. With few exceptions, it is in the form of a
fillet seal.
Sealant - A compound applied to form a seal barrier.
Seal Plane - A surface composed of structure, sealant and fasteners on which the continuity of
seal is established.
Shank Sealing - Sealant compound shall be applied to the hole or to both the shank and the
under head area of the fastener in sufficient quantity that the entire shank is coated and a small
continuous bead of sealant is extruded out around the complete periphery of each end of the
fastener when installed. The fastener shall be installed within the application time of the sealing
compound used.
Squeeze-Out Life - Length of time sealant remains suitable for structure assembly in faying
surface seal application.
Tack-Free Time - Tack-free time is a stage, during the cure of the sealant compound, after which
the sealant compound is no longer tacky. When the sealant compound is pressed firmly with the
knuckles, but no longer adheres to the knuckles, the sealant compound is tack-free.

Materials
A.

Type of Sealants - Sealants are categorized by type of usage. Type I sealants are separated into
classes to differentiate the materials according to method of application. Dash numbers following
the class designation indicate the minimum application time (in hours) for Class A and Class B, and
minimum work life (in hours) for Class C. Refer to Table 212 for application time, curing rate, etc., for
Type I sealants.
(1) Type I - Fuel, pressure, and weather sealant.
(a) Class A - Sealant which is suitable for brush application.
(b) Class B - Sealant which is suitable for application by extrusion gun, spatula, etc.
(c) Class C - Sealant which is suitable in faying surface applications.
(d) Quick Repair Sealant - This material is for use only in making repairs when an extremely
rapid curing sealant is required. A possible application includes sealing a leaking fuel tank
on an airplane which must be dispatched within a few hours.

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CAUTION: Quick repair sealant must be applied within its working life of 15
minutes. Attempts to work quick repair sealant beyond working life
will result in incomplete wetting of surface and will result in a failed
seal.
(2)

Type VIII - Low Adhesion Access Door Sealant. This Class B sealant is designed for sealing
faying surfaces where easy separation of the joined surfaces is required. The sealant has
low adhesion and forms a gasket that molds itself to fill all irregularities between two surfaces.
The sealant is exceptionally resistant to fuels, greases, water, most solvents and oils including
hydraulic oil.
NOTE:

Time periods presented below are based on a temperature of 77°F (25°C) and 50
percent relative humidity. Any increase in either temperature or relative humidity may
shorten these time periods and accelerate the sealant cure.

Table 212. Curing Properties of Type I Sealant

5.

CLASS

APPLICATION
TIME(HOURS,
MINIMUM)

A-1/2

WORK LIFE
(HOURS,
MINIMUM)

TACK-FREE
TIME (HOURS,
MAXIMUM)

CURING RATE
(HOURS,
MAXIMUM)

1/2

10

40

A-2

2

40

72

B-1/2

1/2

4

6

B-2

2

40

72

B-4

4

48

90

C-24

8

24

96

168 (7 days)

C-48

12

48

120

336 (14 days)

C-80

8

80

120

504 (21 days)

General Requirements
A.

When working with sealants, observe the following requirements.
(1) Unmixed sealants shall not be more than two months old when received. These sealants shall
not be more than six months old when used.
(2) Unmixed sealants stored at temperatures exceeding 80°F (27°C) shall be used within five weeks.
(3) Sealants which have been premixed, degassed and flash frozen shall be maintained at -40°F
(-40°C) or lower and shall not be received more than two weeks beyond the date of mixing.
These sealants shall not be used more than six weeks after the date of mixing.
(4) Frozen sealant shall be thawed before being used. If sealant were applied at a temperature
below 60°F (15°C), it would not be sufficiently pliable for proper application and adhesion could
be critically reduced by condensation of moisture. On the other hand, although sealant must
extrude freely for proper application, it would be subject to excessive slumping if applied at a
temperature above 80°F (27°C). Frozen sealant may be thawed by any suitable means which
does not cause contamination or overheating of the sealant and does not shorten the application
time of the sealant to an impractical period. Examples: Thawing by exposure to ambient air
temperature, accelerated thawing by exposure in a constant temperature bath (using clean, hot
water), accelerated thawing in a microwave oven. In any case, thawing temperature and time
shall be adjusted to give a thawed sealant temperature between 60°F, and 80°F (15°C and 27°C)
at the time the sealant is applied.
(5) Mixed, frozen sealants which have thawed shall not be refrozen.
(6) Complete preassembly operations, such as fitting, filing, drilling, countersinking, dimpling and
deburring, prior to cleaning and sealant application.

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(7)

Surfaces must be clean and dry, free from dust, lint, grease, chips, oil condensation or other
moisture and all other contaminating substances prior to the application of sealant.
(a) All exposed bonding primer or bonded assemblies which are to be sealed shall be cleaned
using Scotch Brite followed by solvent cleaning using Trichloroethane.
NOTE:

(8)

(9)
(10)
(11)
(12)

(13)
(14)
(15)
(16)
(17)

6.

Bond primer shall not be removed, just lightly scuffed with Scotch Brite.

Sealant materials may be applied to unprimed or primed surfaces. Nonchromated or epoxy
primers shall have good adhesion to the substrate material and shall have aged at least 48
hours prior to sealant application. Adhesive bonding primer shall be scotchbrited and cleaned
before applying sealant.
Sealants shall not be applied when the temperature of either the sealant or the structure is below
60°F (15°C).
Sealant applied by the fillet or brush coat methods shall always be applied to the pressure side
of a joint if possible.
After application, sealants shall be free of entrapped air bubbles and shall not exhibit poor
adhesion. All fillets shall be smoothed down and pressed into the seam or joint with a filleting
tool before the sealant application time has expired.
Where fasteners have been shank or under head sealed, extruded sealant shall be evident
around the complete periphery of the fastener to indicate adequate sealing. Sealant extruded
through a hole by a rivet shall be wiped from the end of the rivet before bucking. Threaded
fasteners which have been shank or under head sealed shall not be retorqued after the expiration
of the application time of the sealant. Prior to torquing, sealant shall be removed from the
threads. In torquing, turn the nut rather than the bolt, if possible.
Pressure testing shall not be accomplished until the sealant is cured.
Sealant shall not be applied over ink, pencil or wax pencil marks. If these materials extend into
the sealing area, they must be removed.
If sealing is to be accomplished over primer and the primer is removed during the cleaning
process, it is permissible to seal directly over the cleaned area and then touch up the exposed
areas after the sealant has been applied and is tack free.
Sealed structure shall not be handled or moved until sealant is tack free (sealant may be
dislodged or have the adhesion damaged). Excessive vibration of structure, such as riveting,
engine run up, etc. is not permitted.
Drilling holes and installing fasteners through a fay sealed area shall be performed during the
working life of the faying sealant or the entire shank and area under fastener head shall be fay
sealed.

Sealant Curing
A.

Room Temperature.
(1) Room temperature curing properties are based on a temperature of 77°F, +5 or -5°F (25°C, +3
or - 3°C) and a relative humidity of 50 percent unless otherwise indicated.
(2) Room temperature curing properties of Type I sealants are given in Table 212.
(3) Curing properties of Type VIII, Class B sealants are the same as for Type I, Class B. Adhesion
to aluminum should be (peel) less than two pounds per inch width (1.4 N per 10 mm width).

B.

Accelerated Curing.
(1) Accelerated curing of sealant can be accomplished in several ways. The procedure to be used
is dependent on the type of sealant and other factors.
(2) The cure of Type I sealants can be accelerated by an increase in temperature and/or relative
humidity. Warm circulating air at a temperature not to exceed 140°F (60°C) may be used to
accelerate cure. Heat lamps may be used if the surface temperature of the sealant does not
exceed 140°F (60°C). At temperatures above 120°F (49°C), the relative humidity will normally
be so low (below 40 percent) that sealant curing will be retarded. If necessary, the relative
humidity may be increased by the use of water containing less than 100 parts per million total
solids and less than 10 parts per million chlorides.

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7.

Mixing of Sealants
A.

Requirements.
(1) Sealants shall be mixed or thinned in accordance with the manufacturers recommendations and
thoroughly blended prior to application. All mixed sealant shall be as void free as possible.
(2) Prior to mixing, the sealing compound base and its curing agent, both in their respective original
unopened containers, shall be brought to a temperature between 75°F and 90°F (24°C and
32°C) along with all required mixing equipment.

B.

Sem-Kit Mixing. (Refer to Figure 201)

WARNING: The cartridge should be held firmly, but must not be squeezed,
as the dasher blades may penetrate the cartridge and injure
the hand.
(1) Pull dasher rod to the FULL OUT position so that the dasher is at the nozzle end of the cartridge.
(2) Insert ramrod in the center of the dasher rod against the piston and push the piston in
approximately one inch (25 mm).
NOTE:

Extra force will be needed on the ramrod at the beginning of accelerator injection into
the base material.

(3) Move the dasher rod in approximately one inch (25 mm), then push piston in another inch (25
mm). Repeat this action until accelerator is distributed along the entire length of the cartridge.
NOTE:

The accelerator has been fully injected into the cartridge when the ramrod is fully
inserted into the dasher rod.

(4) Remove and properly discard the ramrod.
NOTE:

Mixing the accelerator and base material can be accomplished manually, or as an
alternate method, with the use of a drill motor.

(5) Manual Mixing.
(a) Begin mixing operation by rotating the dasher rod in a clockwise direction while slowly
moving it to the FULL OUT position.
NOTE:

Do not rotate the dasher rod counterclockwise; the four-blade dasher inside the
cartridge will unscrew and separate from the dasher rod.

(b) Continue clockwise rotation and slowly move the dasher rod to the FULL IN position.
A minimum of five full clockwise revolutions must be made for each full out stroke and
1
for each full in stroke of the dasher rod. Approximately sixty strokes are necessary
for a complete mix.
NOTE:

If streaks are present in the sealant (viewing through the side of the
cartridge), the sealant is not completely mixed.

(c) End mixing operation with the four blade dasher at the bottom of the cartridge.
(d) Hold cartridge upright; unscrew dasher rod from the four blade dasher by gripping the
cartridge at the four blade dasher and turn the dasher rod counterclockwise. Remove
dasher rod.
(e) Screw appropriate nozzle into the cartridge. If sealant gun is to be used, install cartridge
in gun.

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B1110

CARTRIDGE
FOUR-BLADE

DASHER
ATERIAL

ACCELERATOR

DASHER
HANDLE

NOTE:

CARTRIDGE IS DISPOSABLE AFTER USE.

5580T1044

Two-Part Sealant Cartridge
Figure 201 (Sheet 1)

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(6)

Drill motor mixing.
NOTE:
(a)

A tapered rotary file or a 25/64-inch drill bit may be used with a drill motor to turn the
dasher rod.

Insert the rotary file/drill bit into the dasher rod approximately 1/2 inch (13 mm).

WARNING: The cartridge should be held firmly, but not squeezed, as
the dasher blades may penetrate the cartridge and injure
the hand.
(b)
(c)

Verify the drill motor will rotate the dasher rod clockwise (looking toward the nozzle end of
the cartridge).
With the cartridge held firmly in one hand and the drill motor in the other, rotate the dasher
rod at approximately 50 revolutions-per-minute while moving the dasher rod to FULL IN
and FULL OUT positions.
1
Mix sealant for at least 50 strokes (a stroke is one complete full in and full out stroke
of the dasher rod).
NOTE:

(d)
(e)
(f)
8.

If streaks are present in the sealant (viewing through the side of the
cartridge), the sealant is not completely mixed.

End mixing operation with the four blade dasher at the bottom of the cartridge.
Hold cartridge upright; remove drill motor and rotary file/drill bit from the dasher rod;
unscrew dasher rod from the four blade dasher by gripping the cartridge at the four blade
dasher and turn the dasher rod counterclockwise. Remove dasher rod.
Screw appropriate nozzle into the cartridge. If sealant gun is to be used, install cartridge
in gun.

Cleaning
A.

All surfaces to which sealant is to be applied shall be clean and dry.

B.

Remove all dust, lint, chips, shavings, etc. with a vacuum cleaner where necessary.

C.

Cleaning shall be accomplished by scrubbing the surface with clean cheesecloth moistened with
solvent. The cloth shall not be saturated to the point where dripping will occur. For channels and
joggles, pipe cleaners and/or funnel brushes may be used instead of cheesecloth.
(1) The solvents to be used for the cleaning in the integral fuel tank are A-A-59281 or TT-M-261
for the first or preliminary cleaning. For the final cleaning, 0-T-620, 1, 1, 1 - Trichloroethane,
Technical, Inhibited only must be used.

D.

The cleaning solvent should never be poured or sprayed on the structure.

E.

The cleaning solvent shall be wiped from the surfaces before evaporation using a piece of clean, dry
cheesecloth in order that oils, grease, wax etc., will not be redeposited.

F.

It is essential that only clean cheesecloth and clean solvent be used in the cleaning operations.
Solvents shall be kept in safety containers and shall be poured onto the cheesecloth. The cheesecloth
shall not be dipped into the solvent containers and contaminated solvents shall not be returned to the
clean solvent containers.

G.

Final cleaning shall be accomplished immediately prior to sealant application by the person who is
going to apply the sealant.
(1) The area which is to be sealed shall be thoroughly cleaned. A small clean paint brush may
be needed to clean corners, gaps, etc. Always clean an area larger than the area where the
sealant is to be applied. Never clean an area larger than 30 inches (0.8 m) in length when
practical. When the area is being scrubbed with a moistened cloth in one hand, another clean
dry cloth shall be held in the other hand and shall be used to dry the structure. The solvent must
be wiped from the surfaces before it evaporates.

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MAINTENANCE MANUAL
(2) The above procedure shall be repeated until there is no discoloration on the clean drying cloth.
Marks resulting from wax or grease pencils must be removed from parts prior to sealing.

9.

H.

Allow all cleaned surfaces to dry a minimum of 5 minutes before the application of sealant materials.

I.

Sealant shall be applied as soon as possible after cleaning and drying the surfaces to be sealed.
Do not handle the parts between the cleaning and sealing operations. Sealant application personnel
handling cleaned surfaces shall wear clean white gloves to prevent surface contamination. In the
event contamination does occur, the surfaces shall be recleaned.

J.

Safety precautions should be observed during the cleaning and sealing operation. Cleaning solvents
are toxic and flammable in most cases. Fresh air masks and/or adequate ventilation are required for
all closed areas. The structure shall be electrically grounded before starting any cleaning or sealing
operation.

Sealing Application
A.

General.
(1) All new sealing shall be accomplished using the type of sealing material required for the area
being sealed. All sealant repairs shall be accomplished using the same type of sealing material
as that which is being repaired.
(2) Application time of the sealing compound shall be strictly observed. Material which becomes
too stiff and difficult to work or which does not wet the surface properly shall be discarded even
though the application time has not expired.
(3) For an illustration of the integral fuel compartment and sealing techniques, refer to Figure 202.
(4) Prior to sealant application, all surfaces to be sealed shall be cleaned. Refer to Cleaning.

B.

Fay Surface Sealing (Refer to Figure 202).
(1) A fay surface seal must be made when a new structure is added to the airplane and a fay surface
seal is necessary.
(a) The fay sealed joints must be closed and attached before the work life is expired as given
in Table 212.
(2) A fay surface seal must be made when the structure and/or parts have been disassembled for
causes other than a defective seal.
(a) Fay sealed joints must be closed and attached before the work life is expired as given in
Table 212.
(3) A fay sealed joint must have sufficient sealant applied so the space between the assembled fay
surfaces is filled with sealant.
(a) A small quantity of sealant must come out in a continuous bead around the edges.
(4) Countersink or ream the holes through the fay sealed joints with temporary or permanent
fasteners installed.
(a) Metal work operations must be completed before the clean and seal operations.
NOTE:

Fabrication and changes done after the seal are not recommended.

(b) Countersink or ream holes through the fay sealed joint with permanent fasteners in every
other hole.
1
Use temporary fasteners (Clecos or bolts) if assembly with permanent fasteners is
not possible.
2
Temporary fasteners must be replaced by permanent fasteners before the expiration
of the fay surface sealant.
3
Remove temporary fasteners and install permanent fasteners with wet sealing
compound.
(5) Immediately after the assembly is completed and all permanent fasteners are installed, remove
any sealant that has not cured and unwanted sealant with clean rags moist with A-A-59107,
Toluene or Methyl n-Propyl Ketone.

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MAINTENANCE MANUAL

B1111

INSPECTION
PANEL
(TYPICAL)

RAILING

SKIN

TO
SKI

rii

-'

Tf~

n

A

T-ri jrkI

TRAILING EDGE

B(
RSt
v .....

05261010
05261009
05261011

Integral Fuel Compartment Sealing
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL

B1112

FAYING SURFACE SEAL

TYPICAL RIB
SECTION

SEALANT EXTRUDED
CONTINUOUSLY

J

FAY SEAL
(SEALANT
EXTRUDED
CONTINUOUSLY)

\I~~~~~~~~~~~
__

5598T2007
5598T2007

Integral Fuel Compartment Sealing
Figure 202 (Sheet 2)

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MAINTENANCE MANUAL

B1377

11

I

I

II \,\

I

I

/y7

f4•4
Arl""

1

PSh
I

NOTE:

THE EXAMPLES SHOW TYPICAL CROSS SECTIONS OF DIFFERENT SEAL METHODS
USED IN THE FUEL COMPARTMENT. THE MINIMUM SEALANT THICKNESS AT ANY POINT
MUST NOT BE LESS THAN 0.060 INCH (1.5 mm).
5598T1010
6280T1003

Integral Fuel Compartment Sealing
Figure 202 (Sheet 3)

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MAINTENANCE MANUAL

B1113

)

PNEUMATIC
SEAL TOOL

55981009

Integral Fuel Compartment Sealing
Figure 202 (Sheet 4)

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MAINTENANCE MANUAL
C.

Injection Sealing (Refer to Figure 202).
(1) Sealant must be put into the channel, void, or any open space from one point only with a
pneumatic sealant tool.
(a) After sealant is added, air must not be trapped in the channel, void, or any open area.
(b) Sealant must be seen at the opposite opening.
1
Cause a blockage at each channel or exit as the sealer is applied in the area so that
sealant is seen at the openings of all applicable channels.
(2) Sealant must be put into wire bundles that go through firewalls and bulkheads to fill any voids
and open areas between the wires.
(a) Bundle ties must be no more than 6 inches (152.4 mm) from the location to be sealed.
(b) Pull the wires apart from each other.
Layer each wire with sealant over the length which goes through the bulkhead or seal
1
assembly.
2
Layer each wire with sealant 0.5 inch (12.7 mm) added length on each side of the
bulkhead or seal assembly.
3
Pull the wires through the bulkhead or seal assembly into position.
4
Fill the open areas of the wires that remain until the sealant is seen from the opposite
side.
(3) Remove unwanted sealant before the work life of the sealant is expired.
(4) Use an applicable tool to make the sealant smooth and flush with the surface.

D.

Fillet Sealing.
(1) Fastener considerations:
(a) Do not fillet seal any parts until they are held completely together by permanent fasteners.
(b) Prior to filleting the periphery of bolted structure and fittings, it is necessary that all bolts,
accomplishing the attachment, be properly torqued.
(2) The sealant shall be applied using a sealant gun or spatula.
(3) When using a sealant gun for fillet sealing, the nozzle tip shall be pointed into the seam or joint
and shall be maintained nearly perpendicular to the line of travel. A continuous bead of sealant
shall precede the tip and the tip size, shape and rate of travel shall be such that sufficient sealant
shall be applied to produce the required fillet.
(4) Fillets shall be shaped or formed to meet the size and shape requirements as shown in applicable
figures using the nozzle tip and/or fairing tools to press against the sealant while moving parallel
to the bead. Exercise caution to prevent folds and entrapment of air during application and
shaping of the fillet and work out any visible air bubbles. The fillet shall be formed so that the
highest portion of the fillet is centered over the edge of the structure or fitting. Lubrication in
any form shall not be used for smoothing purposes. In all cases, fillet size shall be kept as near
minimum as practical.
(5) Where it is more convenient or fillet slumping is encountered, the fillet may be applied in two
stages. A small first fillet should be applied which is allowed to cure to a tack-free state, followed
by a second application of sealant sufficient to form the final fillet conforming to the specified
dimensions for a fillet seal. If the first fillet has cured, it must be cleaned before the second
application of sealant is made. If the fillet has only cured to a tack-free state, it shall be wiped
lightly with a gauze pad or cheesecloth pad dampened with cleaning solvent.
(6) Allow the sealant to cure to a tack-free condition prior to the airplane being moved, handled
and/or worked on.
(7) In cases where a fillet seal connects to an injection seal, the full bodied fillet shall extend past
the end of the injection and then taper out.
(8) Lap joint and seam fillets shall be as shown in Figure 202 .
(9) Butt joint fillets shall be as shown in Figure 202.
(10) Bolts shall be fillet sealed as shown in Figure 202. The area for sealing shall consist of the area
of the structure surrounding the base of the fastener end plus the entire exposed area of the
fastener. An optional method of sealing threaded fasteners is to apply a brush coat of Type I,
Class A sealant. Where brush coating is used as the method of sealing threaded fasteners,
the sealant must be worked around each fastener with a stiff brush and considerable care to be
effective. A simple pass of the brush with the sealant is not sufficient to produce an effective
seal.

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(11) Dome type nutplates shall be fillet sealed as shown in Figure 202. The area for sealing shall
consist of the area of the structure surrounding the base of the fastener and from there up over
the rivets to the dome.
(12) Hole filling and slot fillets shall be as shown in Figure 202.
(a) Tooling holes shall be plugged with a shank sealed soft rivet and then brush coated with
Type I, Class A sealant.
10.

Sealant Repair
A.

B.

Materials - Repairs, in general, shall be accomplished with the same type of material as that being
repaired.
NOTE:

Type I, Class B-1/2 is recommended for use during cold weather to obtain an accelerated
cure.

NOTE:

Type I, Quick Repair sealant may be used as a repair for sealant in fuel tanks if desired for
fast cure and rapid dispatch.

Temperature Requirements.
(1) The structure shall be above 60°F (15°C) before the sealant is applied and shall remain above
60°F (15°C) until the sealant is tack-free.
NOTE:

For outside operations only, the temperature of the structure may be allowed to drop
below 60°F (15°C) but not below 58°F (14°C), after application for a period of time
not to exceed 48 hours; however, the structure must be subsequently heated to
above 60°F (15°C) and the sealant allowed to become tack-free before the tanks
are refueled.

(2) The maximum air temperature allowed to come in contact with the curing sealant is 120°F (49°C).
C.

Fillet and Fastener Sealing Repairs.
(1) Repair of damaged or faulty sealant applications shall be accomplished as follows:
(a) Remove all damaged or faulty sealant to ensure solid residual material.
(b) Sealant shall be cut to produce a smooth continuous scarfed face. The sealant shall be
completely removed in the affected areas. The cutting tools should only be made from
nonmetallic materials that are softer than aluminum.
(c) Inspect repair areas for clean and smooth cuts. Loose chunks or flaps of sealant on the
cut areas shall be removed.
(d) Clean the area to be sealed, including the scarfed face of the old seal. Refer to Cleaning.
(e) Apply new fillet seals. Slight overlapping of the fresh material over the existing fillet is
permissible. A large buildup of sealant shall not be allowed.
(f) Rework of a fillet which has been oversprayed or brushed with primer shall be
accomplished by a scarfed joint and removal of the fillet having primer on it, in the area of
the repair. The primer shall not be sandwiched between the old and new sealants.
(g) If the primer is removed during the cleaning operation, it is permissible to apply the new
fillet seal directly over the clean bare metal and then touch up with the proper primer all
exposed areas of bare metal after the sealant has been applied.

D.

Faying Surface Sealing Repair - After determining the area which contains the faulty and/or leaking
faying surface seal, the repair shall be accomplished by applying a fillet seal along the edge of the
part adjacent to the faying surface seal long enough to fully cover the area of the faulty and/or leaking
seal.

E.

Brush Coat Sealing Repair - Repair of damaged or leaking brush coat seals shall be accomplished by
removing the discrepant brush coat. Clean the area of sealant removal and the surrounding structure
and sealant. Refer to Cleaning. Apply a new brush coat of sealant.

F.

Integral Fuel Tank Sealing Using PR-1826 Class B Rapid Curing Sealant.
(1) Remove damaged section of sealant with a sharp plexiglass scraper. Taper all cuts in old sealant
at 45-degree angles.
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(2) Thoroughly clean with solvent and abrade old areas which are to be over coated. Clean one
small area at a time, then dry with a clean cloth before the solvent evaporates.
NOTE:

Always pour solvent on the cloth to maintain a clean solvent supply.

NOTE:

In fuel tanks which have been in operation, the sealant will be soaked and should be
dried in area of the repair with a vapor proof heat lamp or hot air blower before new
sealant is applied.

(3) After the surface has been cleaned and dried, apply a heavy layer of PR- 1826 Adhesion
Promoter with a clean brush or gauze pad. Allow adhesion promoter a minimum of 30 minutes
to dry.
NOTE:

Care must be taken to obtain a uniform thin coat of adhesion promoter. Thin enough
to cover the surface, but not heavy enough to run.

(4) Mix PR-1826 Class B sealant according to instructions supplied with the material.
(5) Apply PR-1826 Class B sealant, 0.125 to 0.375 inch (3.2 to 9.5 mm) thick, to the repair area
with a spatula or paddle shaped tool. Firmly press sealant in place and form to desired shape.
Overlap PR-1826 Class B sealant over old sealant from 0.125 to 0.25 inch (3.2 to 6.4 mm).
NOTE:

Sealant may be applied up to 8 hours after the application of adhesion promoter. After
8 hours, the surface should be recleaned and adhesion promoter reapplied.

(6) Allow sealant to cure a minimum of 2 hours at 77°F (25°C) before refueling. Curing time is based
solely on temperature and will be halved for every 18°F (10°C) increase, and doubled for every
18°F (10°C) decrease from the standard 77°F (25°C).
G.

Firewall Wire Bundle Seal Assembly.
(1) Complete fay surface sealing of the mating parts
Refer to Sealing Application.
(a) Seal only with Type IV Dapco 2100 or seal
Equipment.
(2) Complete injection sealing of the wire bundle that
Sealing Application.
(a) Seal only with Type IV Dapco 2100 or seal
Equipment.

of the seal assembly plate and the firewall.
with Type IV Q3-6077. Refer to Tools and
passes through the seal assembly. Refer to
with Type IV Q3-6077. Refer to Tools and

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CONVERSION DATA - DESCRIPTION AND OPERATION
1.

2.

General
A.

This section contains information for converting the more commonly used measuring units found in this
manual from the common United States system to the International System of Units (metric system).

B.

Other conversion factors may be found in manuals such as Standard for Use of the International
System of Units (SI): The Modern Metric System, prepared by ASTM, 100 Bar Harbor Drive, West
Conshohocken, PA 19428-2959 USA.

Conversion Factors
A.

B.

Distance and Length
(1) Multiply inches by 25.4 to obtain mm (millimeters).
(2) Multiply feet by 0.3048 to obtain m (meters).
Mass
(1) Multiply ounces by 28.35 to obtain g (grams).
(2) Multiply pounds by 0.436 to obtain kg (kilograms).

C.

Temperature
(1) Subtract 32 from degrees Fahrenheit and multiply by 5/9 to obtain degrees Celsius.

D.

Torque
(1) Multiply inch-pounds by 0.11298 to obtain Newton-meters.
(2) Multiply foot pounds by 1.3588 to obtain Newton-meters.

E.

Force
(1) Multiply pounds of force by 4.4482 to obtain N (Newtons).

F.

Pressure
(1) Multiply pressure (psi) by 6.8948 to obtain kPa (kiloPascals).
Mass flow

G.

(1)

Multiply pounds-per-hour by 1.26 X 10- 4 to obtain kg/sec.

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CHAPTER

AIR CONDITIONING

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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Apr 7/2003

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Apr 7/2003

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Apr 7/2003

21-21-00

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Jan 2/2006

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Apr 7/2003

21-Title
21-List of Effective Pages
21-Record of Temporary Revisions
21-Table of Contents

© Cessna Aircraft Company

21 - LIST OF EFFECTIVE PAGES

Page 1of 1
Jan 2/2006

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
AIR CONDITIONING - GENERAL .................................................

Scope ......................................................................
Tools, Equipment and Materials .........
.........
............................
Definition...................................................................

21-00-00
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Page
Page
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1
1
1
1

FRESH AIR DISTRIBUTION - DESCRIPTION AND OPERATION ....................
G eneral ....................................................................
Description ......... ...........
.............................................
System Operation ..........................................................

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Page
Page
Page

1
1
1
1

FRESH AIR DISTRIBUTION - MAINTENANCE PRACTICES ........................
General ....................................................................
Air Outlet Valve Removal/nstallation ..........................................
AVIONICS COOLING FAN - MAINTENANCE PRACTICES ..........................
General...................................................................
Cooling Fan Removal/nstallation .............................................
Primary Function Display (PFD) Fan Removal/Installation ......................
Multi-Function Display (MFD) Fan Removal/Installation.........................
Deck Skin Fan Removal/Installation ..........................................
Tailcone Avionics Fan Removal/Installation ....................................
Primary Flight Display (PFD) and Multi-Function Display (MFD) Fan Operational
Check ...................................................................

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21-20-00
21-21-00
21-21-00
21-21-00
21-21-00
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21-21-00
21-21-00

HEATING AND DEFROSTING - MAINTENANCE PRACTICES ......................
General ...................................................................
System Operation...........................................................
System Troubleshooting .....................................................
Heat Exchanger Removal/Installation .........................................
Shutoff Valve Removal/nstallation ............................................
Control Cable Removal/Installation ...........................................
Distribution System Components Removal/Installation..........................

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Page
Page

201
201
201
201
201
204
204

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21 - CONTENTS

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Page
Page
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Page
Page
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Page

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201
201
201
201
201
203
203

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
AIR CONDITIONING - GENERAL
1.

Scope
A.

2.

This chapter describes those units and components which furnish a means of ventilating and heating
the cockpit/cabin area.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes may be used for the following items:

NAME

NUMBER

MANUFACTURER

USE

Type II Sealant

PR1488

Courtaulds Aerospace
5426 San Fernando Rd.
Glendale, CA 91209

To secure cabin duct to
various air outlets.

Type IV Sealant

Pro-Seal 700

Courtaulds Aerospace

To seal shutoff valve to
firewall.

Type IV Sealant

GC- 1900

Courtaulds Aerospace

To seal shutoff valve to
firewall.

3.

Definition
A.

This chapter is divided into sections to aid maintenance technicians in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief description of the
sections follows:
(1) The section on fresh air distribution describes that portion of the system used to induct and
distribute fresh air throughout the cockpit/cabin area.
(2) The section on avionics cooling describes those components used to provide forced air cooling
to the rear of the avionics racks.
(3) The section on heating describes those components used to generate and distribute heat for the
cockpit/cabin area.

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MAINTENANCE MANUAL
FRESH AIR DISTRIBUTION - DESCRIPTION AND OPERATION
1.

General
A.

2.

Description
A.

3.

The cockpit/cabin area is ventilated with fresh air by means of external wing root openings, an
adjustable air scoop, and internal ducting.

Fresh air enters into the cabin from one of five sources. Four of those sources are located in the
leading edge area of the wing (two left and two right) and the fifth source is located on the right side
of the fuselage, between the firewall and the forward door post.
(1) Each wing leading edge area contains two inlet scoops. One inlet scoop feeds an air valve
located at the wing leading edge/windshield intersection; and the other inlet scoop (located in
the wing-to-fuselage fairing) feeds a pair of air valves located near the mid torso area (front seat)
and overhead area (rear seat).
(2) Fresh air may also be introduced by an adjustable door located on the fuselage. This air is
routed directly into the heated air plenum and is distributed through the heated air distribution
system.

System Operation
A.

The amount of fresh air entering the cabin can be controlled by any of the six air valves. Rotating the
air valve will vary the airflow from fully closed to fully open.

B.

Air flow into the cabin can also be controlled by the CABIN AIR control cable. Pulling the control aft
allows the maximum amount of fresh air to flow through the heated air distribution system. Pushing
the control forward closes the door and allows no fresh air to flow through the heated distribution
system.
NOTE:

Air temperature in the heated air distribution system can be altered by use of the CABIN
HT control in conjunction with the CABIN AIR control. With the CABIN AIR control fully
aft and the CABIN HT control full forward, only ambient temperature air fill flow through
the heated air distribution system. As the CABIN HT control is gradually pulled out, more
and more heated air will blend with ambient temperature air and be distributed through the
heated air distribution system. Either one or both of the controls may be set at any position
from full open to full closed.

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MAINTENANCE MANUAL
FRESH AIR DISTRIBUTION - MAINTENANCE PRACTICES
1.

General
A.

2.

Fresh air outlet valves are located in the cockpit/cabin area at upper corners of the windshield, in the
sidewalls just aft of the instrument panel, and above the passenger seat. Air outlet valve removal/
installation is typical at each location.

Air Outlet Valve Removal/Installation
A.

Remove Air Outlet Valve (Refer to Figure 201).
(1) Remove retaining ring from air outlet valve.
(2) Remove upholstery panel. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(3) Remove clamp securing ducting hose to air outlet valve adapter.
(4) Remove air outlet valve and adapter.

B.

Install Air Outlet Valve (Refer to Figure 201).
(1) Install air outlet valve and valve adapter to ducting. Secure with clamp.
(2) Install upholstery panel. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(3) Install retaining ring to air outlet valve.

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MAINTENANCE MANUAL
. A_ .

PLENUM

DUCT
\

AIR OUTLET

AIR
INLET
ASSEMBLY

DETAIL

AIR
OU
VAL

A

LEFT SIDE SHOWN
RIGHT SIDE OPPOSITE

LLtINUM

U/tr

0510T1007
A0514T1015

Fresh Air Distribution
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B1692

FITTING

I

/
CHEON

AIR VALVE
TDUCT
FS 23.69

DETAIL B
RIGHT SIDE SHOWN
LEFT SIDE OPPOSITE

DETAIL C

0510T1007
B0514T1016
C0514T1017

Fresh Air Distribution
Figure 201 (Sheet 2)

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MAINTENANCE MANUAL
AVIONICS COOLING FAN - MAINTENANCE PRACTICES
1.

General
A.

2.

Cooling Fan Removal/Installation
A.

B.

3.

The avionics cooling fan is found behind the instrument panel and is used to make cool the different
components in the radio stack. Maintenance on the system is only to remove and install the cooling
fan and related ducts.

Remove the Cooling Fan (Refer to Figure 201).
(1) Make sure that the airplane MASTER and AVIONICS switches are in the off position.
(2) Disconnect the negative lead from the battery terminal. Refer to Chapter 24, Battery Maintenance Practices.
(3) Remove the bolts that attach the cooling fan to the firewall.
(4) Disconnect the electrical connector (PC901) from the avionics cooling fan.
(5) Disconnect the flexible ducts from the cooling fan.
(6) Remove the cooling fan from the airplane.
Install the Cooling Fan (Refer to Figure 201).
(1) Connect the flexible ducts to the cooling fan. Install the tie wraps.
(2) Connect the electrical connector (PC901) to the cooling fan.
(3) Install the cooling fan to the firewall with the bolts.
(4) Connect the negative lead to the battery terminal. Refer to Chapter 24, Battery - Maintenance
Practices.
(5) Do a test of the cooling fan for correct operation in the steps that follow.
(a) Put the MASTER switch in the BAT position.
(b) Put the AVIONICS master switch in the ON position.
(c) Listen for the operation of the fan.
(d) Put the AVIONICS master switch and the MASTER switch in the off positions.

Primary Function Display (PFD) Fan Removal/nstallation
NOTE:
A.

B.

4.

The procedures that follow are for airplanes with Garmin G1000.
Remove the PFD Fan (Refer to Figure 202).
(1) Record the fan airflow direction.
(2) Make sure that the MASTER and AVIONICS switches are in the off position.
(3) Remove the PFD. Refer to Chapter 34, Garmin Display Unit (GDU) - Maintenance Practices.
(4) Remove the screws and nuts that attach the fan to the fan bracket.
(5) Disconnect the electrical connector (PC1316) from the avionics fan.
(6) Remove the fan from the airplane.
Install the PFD Fan (Refer to Figure 202).
(1) Connect the electrical connector (PC1316) to the avionics fan.
(2) Make sure that the airflow is directed to the PFD.
(3) Install the screws and nuts that attach the fan to the fan bracket.
(4) Complete a test of the fan.
(a) Put the MASTER and AVIONICS switches in the ON position.
(b) Listen for the operation of the fan.
(5) Set the MASTER and AVIONICS switches in the off positions.
(6) Install the PFD. Refer to Chapter 34, Garmin Display Unit (GDU) - Maintenance Practices.

Multi-Function Display (MFD) Fan Removal/Installation
NOTE:
A.

The procedures that follow are for airplanes with Garmin G1000.
Remove the MFD Fan (Refer to Figure 202).
(1) Record the fan airflow direction.
(2) Make sure that the MASTER and AVIONICS switches are in the off position.
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MAINTENANCE MANUAL

FLEXIBLE DUCT
- (TO AVIONICS STACK)

ELECTRICAL
CONNECTOR
(PC901)

-

DETAIL

FIREWALL
AVIONICS
FAN

A
051 T1 007
A0518T1026

Avionics Cooling Fan Installation
Figure 201 (Sheet 1)

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A

HER

NUT

ELECTRICAL

DETAIL

A

CONNECTOR
(P1316)

0510T1007
A0518T1104

Avionics Cooling Installation
Figure 202 (Sheet 1)

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(3) Remove the turn coordinator. Refer to Chapter 34, Attitude and Direction - Maintenance
Practices.
(4) Remove the screws and nuts that attach the fan to the fan bracket.
(5) Disconnect the electrical connector (PI315) from the avionics fan.
(6) Remove the fan through the turn coordinator hole.
(7) Remove the fan from the airplane.
B.

5.

Install the MFD Fan (Refer to Figure 202).
(1) Connect the electrical connector (PI315) to the avionics fan.
(2) Make sure that the airflow is directed to the MFD.
(3) Install the fan through the turn coordinator hole.
(4) Install the screws and nuts that attach the fan to the fan bracket.
(5) Complete a test of the fan.
(a) Set the MASTER switch and AVIONICS switch to the ON position.
(b) Listen for the operation of the fan.
(6) Set the AVIONICS switch and MASTER switch to the off positions.
(7) Install the turn coordinator. Refer to Chapter 34, Attitude and Direction - Maintenance Practices.
(8) Install the MFD. Refer to Chapter 34, Garmin Display Unit (GDU) - Maintenance Practices.

Deck Skin Fan RemovalInstallation
NOTE:

6.

The procedures that follow are for airplanes with Garmin G1000.

A.

Remove the Deck Skin Fan (Refer to Figure 202).
(1) Record the fan airflow direction.
(2) Make sure that the MASTER and AVIONICS switches are in the off position.
(3) Remove the PFD. Refer to Chapter 34, Garmin Display Unit (GDU) - Maintenance Practices.
(4) Remove the screws and nuts that attach the fan to the deck skin.
(5) Disconnect the electrical connector (PI314) from the deck skin fan.
(6) Remove the fan from the airplane.

B.

Install the Deck Skin Fan (Refer to Figure 202).
(1) Connect the electrical connector (PI314) to the deck skin fan.
(2) Install the screws and nuts that attach the fan to the deck skin.
(3) Make sure that the airflow is directed at the windshield.
(4) Complete a test of the fan.
(a) Set the MASTER and AVIONICS switches to the ON position and listen for the fan
operation.
(5) Set the AVIONICS and MASTER switches in the off positions.
(6) Install the PFD. Refer to Chapter 34, Garmin Display Unit (GDU) - Maintenance Practices.

Tailcone Avionics Fan Removal/nstallation
NOTE:
A.

The procedures that follow are for airplanes with Garmin G1000.

Remove the Tailcone Avionics Fan (Refer to Figure 203).
(1) Make sure that the MASTER and AVIONICS switches are in the off position.
CAUTION:
(2)
(3)
(4)
(5)
(6)

B.

If the engine is removed, make sure there is a tailcone stand in
position before you get inside the tailcone.

Remove the baggage divider to get access inside the tailcone.
Disconnect the electrical connector (PT901) from the fan.
Disconnect the ducts from the fan.
If necessary, remove the caps from the unused ports.
Remove the fan from the avionics shelf.

Install the Tailcone Avionics Fan (Refer to Figure 203).
(1) Make sure the MASTER and AVIONICS switches are in the off position.
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EW
AN

TRANSPONDER

DETAIL

A
0510T1007
A0518T1103

Tailcone Avionics Fan Installation
Figure 203 (Sheet 1)

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CAUTION: If the engine is removed, make sure there is a tailcone stand in
position before you get inside the tailcone.
(2)
(3)
(4)
(5)
(6)
(7)
(8)

I

7.

Set the fan in position and attach it to the avionics shelf.
Connect the ducts to the fan.
If necessary, install the caps on the unused ports.
Connect the electrical connector (PT901) to the fan.
Set the MASTER and AVIONIC switches to the ON position.
Examine the fan to make sure it operates.
Set the baggage divider in position.

Primary Flight Display (PFD) and Multi-Function Display (MFD) Fan Operational Check
A.

PFD
(1)
(2)
(3)
(4)

and MFD Fan Operational Check (Refer to Figure 202).
Remove the PFD and the MFD. Refer to Garmin Display Unit (GDU) - Maintenance Practices.
Put the MASTER and AVIONICS switches in the ON position.
Listen and look for the correct operation of both fans.
Install the PFD and MFD. Refer to Garmin Display Unit (GDU) - Maintenance Practices.

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MAINTENANCE MANUAL
HEATING AND DEFROSTING - MAINTENANCE PRACTICES
1.

General
A.

2.

The heating and defrosting system is comprised of the heat exchange section of the exhaust muffler,
a shut-off valve mounted on the firewall, a push-pull control on the instrument panel, outlets, and
flexible ducting connecting the system.

System Operation
A.

Ram air enters the engine compartment through cowling inlets located aft of the propeller. A portion
of this air is directed toward an exit point in the rear engine baffle. This air is directed, via ducting, to
the heat exchange section of the exhaust muffler. As air passes into the heat exchange and around
the exhaust muffler, it picks up heat from the engine exhaust. This heated air exits the heat exchange
and is directed, via ducting, to a firewall shutoff valve. The shutoff valve is cable controlled from the
cockpit, and controls the amount of heated air entering the cockpit area distribution plenum. From the
plenum, various ducts distribute the heated air to floorboard and defroster outlets.
NOTE:

3.

4.

The cockpit area distribution plenum is also plumbed to receive outside fresh air from the
right hand external air scoop (door). This arrangement allows a combination of fresh air
and heated air to be mixed and distributed throughout the system

System Troubleshooting
A.

Most of the operational troubles in the heating, defrosting and ventilating systems are caused by
sticking or binding air valves and their controls, damaged air ducting or defects in the exhaust muffler.
In most cases, valves or controls can be freed by proper lubrication. Damaged or broken parts must be
repaired or replaced. When checking controls, ensure that valves respond freely to control movement,
that they move in the correct direction, and that they move through their full range of travel and
seal properly. Check that hoses are properly secured, and replace hoses that are burned, frayed
or crushed.

B.

If fumes are detected in the cabin, a thorough inspection of the exhaust system should be
accomplished. Since any holes or cracks may permit exhaust fumes to enter the cabin, replacement
of defective parts is imperative, because fumes constitute an extreme danger.

Heat Exchanger Removal/Installation
A.

Remove Exchanger (Refer to Figure 201).
(1) Remove engine cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Remove c-clamps securing flexible duct to heat exchanger.
(3) Remove sheet metal screws securing heat exchanger to itself.
(4) Carefully remove exchanger from around muffler.
NOTE:

B.

5.

Anytime heat exchanger is removed from around muffler, muffler should be carefully
examined and inspected for leaks or cracks. Refer to Chapter 5, Inspection Time
Limits for normal inspection time frame. Refer to Chapter 78, Exhaust System Maintenance Practices for inspection criteria of the muffler.

Install Exchanger (Refer to Figure 201).
(1) Carefully wrap heat exchanger around muffler.
(2) Secure heat exchanger to itself using sheet metal screws.
(3) Secure flexible duct to heat exchanger using c-clamps.
(4) Install engine cowling. Refer to Chapter 71, Cowling - Maintenance Practices.

Shutoff Valve Removal/Installation
A.

The shutoff valve is riveted to the firewall and is not removed from the airplane during normal
maintenance. If valve is replaced, firewall should be sealed using Type IV sealant upon reattachment
of shutoff valve to firewall. For a list of Type IV sealants, refer to Air Conditioning - General.

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B1

B

,

CLAMP

DETAIL

A

CABIN HEAT CONTROL
II

1./"~r-

IUI

VALVE

IEW
VALVE BODY

DETAIL C

VALVE GUIDE

NOZZLE

AMP

DEFROSTER HOSE

DETAIL

0510T1007
A0514T1019
B0514T1021
C0514T1020

B

Heating and Defrosting Installation
Figure 201 (Sheet 1)

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6.

7.

Control Cable Removal/Installation
A.

Remove Control Cable (Refer to Figure 201).
(1) Remove engine cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Carefully straighten end of cabin heat control cable.
(3) Loosen clamp bolt on control arm and withdraw cable from control arm.
(4) Loosen screws securing clamp bolt to firewall.
(5) From inside the cabin, gain access to the backside of the CABIN HT control cable.
(6) Loosen nut on backside of control cable.
(7) Carefully withdraw cable from instrument panel and firewall.

B.

Install Control Cable (Refer to Figure 201 ).
(1) Thread end of control cable through hole in instrument panel and through hole in firewall.
(2) Secure CABIN HT control cable to backside of instrument panel using existing jam nut.
(3) Thread end of control cable through the clamp bolt.
(4) Tighten clamp bolt and test control cable to ensure full range of travel.
(5) When full range of travel has been established, bend end of control cable around clamp bolt
area.
(6) Install engine cowling. Refer to Chapter 71, Cowling - Maintenance Practices.

Distribution System Components Removal/Installation
A.

The majority of heated air distribution system components are riveted to the airframe and do not
require replacement during normal maintenance. Ducts are secured to these components using
c-clamps. If ducts become damaged or worn, they should be replaced with new hose of equal length.

B.

Ducts are typically attached to various outlets using Type II sealant. For a list of Type II sealants, refer
to Air Conditioning - General.

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AUTO FLIGHT

CESSNA AIRCRAFT COMPANY

MODEL '172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

22-00-00

Page 1

Jan 3/2005

22-10-00

Pages 201-209

Jan 3/2005

22-10-00

Pages 601-606

Jan 3/2005

22-Title
22-List of Effective Pages
22-Record of Temporary Revisions
22-Contents

22 - LIST OF EFFECTIVE PAGES
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RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL -172

MAINTENANCE MANUAL

CONTENTS
AUTO FLIGHT - GENERAL.......................................................

Scope and Definition ........................................................
Tools, Equipment and Materials ......... .....................................
AUTOPILOT - MAINTENANCE PRACTICES .......................................

General ....................................................................
Roll Servo Removal/Installation ..............................................
Pitch Servo Removal/Installation .............................................
Pitch Trim Servo Removal/Installation.........................................
Servo Capstan Clutch Adjustment ............................................
Set the Autopilot Roll Null ....................................................
KAP-140 Autopilot Controller Removal/Installation .............................
AUTOPILOT SERVO - INSPECTION/CHECK ......................................
General ....................................................................
Roll Servo Inspection........................................................
Pitch Servo Inspection.......................................................
Pitch Trim Servo Inspection ..................................................
Pitch Trim Rigging Inspection ................................................

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AUTO FLIGHT - GENERAL

1.

Scope and Definition
A.

2.

This chapter has a single section that gives the removal and installation of the autopilot flight
computers and pitch and roll servo actuators.

Tools, Equipment and Materials
NOTE:

Equivalent alternatives can be used for the items that follow.

NAME

NUMBER

MANUFACTURER

USE

Test Stand

071-06028-0000

Adapter Tool

071-06021-0003

Honeywell International,
Inc.
1 Technology Center
Olathe, KS 66061
Honeywell International,

To hold the servo mount
in position while the
servo clutch torque
setting is adjusted.
To adjust the servo

Inc.

clutch torque setting.

Adapter Pin

071-06021-0002

Honeywell International, To adjust the servo
Inc.
clutch torque setting.

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MAINTENANCE MANUAL
AUTOPILOT - MAINTENANCE PRACTICES
1.

2.

3.

General
A.

A single axis autopilot with heading hold is on airplanes with IFR. Heading hold is used with directional
gyro input and can have VOR, GPS or Localizer input as required.

B.

A dual-axis autopilot is available. The dual-axis system gives both vertical speed and altitude hold
selection.

Roll Servo Removal/Installation
A.

Remove the Roll Servo (Refer to Figure 201).
(1) Make sure the MASTER and AVIONICS switches are in the off position.
(2)
Remove access panel 620AB. Refer to Chapter 6, Access/Inspection Plates - Description and
Operation.
(3) Disconnect the electrical connector from the roll servo.
(4)
Release the control cable tension and loosen the roll servo control cable at the turnbuckle.
(5) Remove the cable guard and cable.
(6) Remove the screws that attach the roll servo to the bracket.
(7) Remove the roll servo from the airplane.
(8) Do an inspection of the servo. Refer to Servo Inspection.

B.

Install the Roll Servo (Refer to Figure 201).
(1) Put the roll servo in position on the bracket.
(2) Attach with the screws.
(3) Connect the electrical connector to the roll servo.
(4) Install the roll servo control cable on the roll servo.
(5) Make sure the aileron and bell crank are in the neutral position.
(6) Wind the control cable around the servo drum approximately 1.25 turns in each direction from
the swaged ball (drum ball detent inboard).
(7) Make sure the flanges of the control cable guard do not touch the control cable.
(8) Make sure the flanges of the control cable guard are on each side of the notches around the
outer edge of the mount.
(9) Use the turnbuckle to adjust the roll servo control cable tension to 15 pounds, +3 or -3 pounds
(66.7 N, +13.34 or -13.34 N).
(10) Install the access panel 620AB. Refer to Chapter 6, Access/Inspection Plates - Description and
Operation.
(11) Put the MASTER and AVIONICS switches in the ON position.
(12) Do a test of the autopilot to make sure it operates correctly. Refer to Introduction, the List of
Manufacturers Technical Publications for the manufacturer's installation manual.

Pitch Servo Removal/Installation
A.

Remove the Pitch Servo (Refer to Figure 201).
(1) Make sure the MASTER and AVIONICS switches are in the off position.
(2) Remove access plates 31 OAR, 340AL and 340AR. Refer to Chapter 6, Access/Inspection Plates
- Description and Operation.
(3) Disconnect the electrical connector from pitch servo.
(4) Release the cable tension and loosen the pitch servo cable at the turnbuckle.
(5) Remove the cable guard and cable.
(6) Remove the bolts that attach the pitch servo to the bracket assembly.
(7) Remove the pitch servo from the airplane.
(8) Do an inspection of the servo. Refer to Servo Inspection.

B.

Install the Pitch Servo (Refer to Figure 201).
(1) Put the pitch servo in position on the bracket assembly and attach with the bolts.
(2) Connect the electrical connector to the pitch servo.
(3) Install the pitch servo control cable on the pitch servo actuator.
(4) Make sure the aileron and bell crank are in the neutral position.

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C

ROLL SERVO CONTROL
CABLE GUARD
(NOTE)
OL CABLE
LEG
AL)

0

CONTROL CABLE

L

D
I

AILERON

-

LOCATION OF

RFI I rtRAlK'

crWArFn RAI I

b-

VIEW A-A
TURNBUCKLE

ROLL SERVO

NOTE:

THE CONTROL CABLES MUST
NOT TOUCH THE CONTROL
CABLE GUARD LEGS

DETAIL

A
0510T1007
A0560T1011
AA0760T1009

Autopilot Servo Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B240

CONTROL CABLE
GUARD LEG
(TYPICAL)

CONTROL CABLE

GUARD

CONTROL CABLES

LOCAT
SWAGI

VIEW B-B

CONTROL CABLE

K

CLAMP BLOCK
CONTRC
CABLE /

PITCH SERVO

CLAMP BLC

B

UlIRIL

.

B0560T1018

BB0560T101

Autopilot Servo Installation
Figure 201 (Sheet 2)

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B241

CONTROL CABLE
GUARD LEG
(TYPICAL)

CONTROL CABLE GUAR

VIEW C-C

PITCH TRIM SERVO

C
CONTROL CABLES

CC0560T1017

Autopilot Servo Installation
Figure 201 (Sheet 3)

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(5) Wind the control cable around the servo drum approximately 1.25 turns in each direction from
the swaged ball (drum ball detent inboard).
(6) Make sure the flanges of the control cable guard do not touch the control cable.
(7) Make sure the flanges of the control cable guard are on each side of the notches around the
outer edge of the mount.
(8) Use the turnbuckle to adjust the pitch servo cable tension to 15 pounds, +3 or -3 pounds (66.7
N, +13.34 or -13.34 N).
(9) Install access plates 31 OAR, 340AL and 340AR. Refer to Chapter 6, Access/Inspection Plates Description and Operation.
(10) Put the MASTER and AVIONICS switches in the ON position.
(11) Do a test of the autopilot to make sure it operates correctly. Refer to Introduction, the List of
Manufacturers Technical Publications for the manufacturer's installation manual.
4.

Pitch Trim Servo Removal/Installation
A.

Remove the Pitch Trim Servo (Refer to Figure 201).
(1) Make sure the MASTER and AVIONICS switches are in the off position.
(2) Remove access plates 31 OAR, 340AL and 340AR. Refer to Chapter 6, Access/Inspection Plates
- Description and Operation.

(3)
(4)
(5)
(6)
(7)
(8)

Disconnect the electrical connector from the pitch trim servo.
Release the cable tension and loosen the pitch trim servo cable at the turnbuckle.
Remove the cable guard and the cable.
Remove the bolts that attach the pitch trim servo to the bracket assembly.
Remove the pitch trim servo from the airplane.
Do an inspection of the servo. Refer to Servo Inspection.

B.

Install the Pitch Trim Servo (Refer to Figure 201).
(1) Put the pitch trim servo in position on the bracket assembly and attach with the bolts.
(2) Connect the electrical connector to the pitch trim servo.
(3) Install the pitch trim servo cable on the pitch trim servo actuator.
(4) Make sure the flanges of the control cable guard do not touch the control cable.
(5) Make sure the flanges of the control cable guard are on either side of the notches around the
outer edge of the mount.
(6) Use the turnbuckle to adjust the pitch trim servo control cable tension to 15 pounds to 20 pounds
(66.7 N to 88.9 N).
(7) Install access plates 31 OAR, 340AL and 340AR. Refer to Chapter 6, Access/Inspection Plates Description and Operation.
(8) Put the MASTER and AVIONICS switches in the ON position.
(9) Do a test of the autopilot to make sure it operates correctly. Refer to Introduction, the List of
Manufacturers Technical Publications, for the manufacturer's installation manual.

C.

Do a check of the pitch trim rigging.
(1) Attach an inclinometer to the trim tab.
(2) Put the trim tab in the 0 degree position.
(3) Manually operate the trim tab to the up and down limits.
(4) Record the limits of travel.
(5) Put an observer at the right-hand access opening of the tailcone.
(6) Put the electrical trim to the full nose-up position until the observer sees the clutch slip.
(7) Turn the manual trim wheel nose-up (test load condition) 1/4 turn more while the clutch slips.
(8) Make sure the swaged ball on the control cable assembly does not turn aft of the tangent point.
(9) Release the trim wheel and disengage the autopilot.
(10) Manually operate the trim to the full nose-up position.
(11) Do a check of the trim tab position with an inclinometer.
(12) Trim tab position that is greater than the limits of travel values recorded is an indication that the
stop blocks slipped.
(a) Do the trim system rigging again.
(b) Make sure the stop block bolts torque is correct.
(c) Repeat the check of the pitch trim rigging.

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(13) If necessary, make adjustments to the swaged ball position.
(a) Put the control cable assembly chain in the applicable position on the gear teeth of the
actuator sprocket.
NOTE:

One chain link adjustment is related to approximately 17 degrees of travel on
the capstan.

(b) Apply the applicable tension to the control cable and repeat the check of the pitch trim
rigging.
(14) Do the procedure again for the full nose-down trim condition.
5.

Servo Capstan Clutch Adjustment
A.

Do a check of the clutch torque setting.
(1) Remove the servo capstan.
(2) Remove the control cable guard from the servo capstan.
(3) Attach the servo capstan on the capstan test stand. Refer to Autopilot - General for a list of tools
and equipment.
(4) Place the adapter tool over the servo capstan.
(5) Insert the adapter pin from the straight up position to attach the adapter tool.
(6) Insert the torque wrench.
(7) Apply 28 VDC (1 amp maximum) electrical power to the test stand.
(8) Do a check of the torque reading with the test stand motor in the clockwise operation.
NOTE:

The check of the torque reading will be done three times.

(a) Put the capstan switch in the clockwise position.
(b) Record the torque reading of the torque wrench.
(c) Put the switch in the off position.
(9) Do a check of the torque reading with the test stand motor in the counterclockwise operation.
NOTE:

The check of the torque reading will be done three times.

(a) Put the capstan switch in the counterclockwise position.
(b) Record the torque reading of the torque wrench.
(c) Put the switch in the off position.
(10) Average the six torque readings.
NOTE:
(11)

The torque reading to be used is the average of the six torque readings.

Refer to Table 201 for the correct torque reading of the servo capstan.

Table 201. KAP-140 Autopilot Servo Clutch Torque Setting
Servo

Clutch Plate Torque

Roll

55, +5 or -5 inch-pounds (6.2, +0.56 or -0.56 N-m)

Pitch

18, +2 or -2 inch-pounds (2.0, +0.23 or -0.23 N-m)
30, +3 or -3 inch-pounds (3.39, +0.34 or -0.34 N-m)
(a) If the torque indication is below the value given in Table 201, rotate the clutch adjust nut
clockwise and do the check of the torque readings again.
(b) If the torque indication is above the value given in Table 201, rotate the clutch adjust nut
counterclockwise and do the check of the torque readings again.
(12) Record the slip clutch torque indication, airplane type, axis and date on the decal attached to
the servo mount body.

Pitch Trim

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MODEL 172
MAINTENANCE MANUAL
(13) Install the control cable guard on the servo capstan.
(14) Install the servo capstan.
6.

Set the Autopilot Roll Null
A.

Set the Autopilot Roll Null (If the Autopilot is Installed).
(1) Make sure the autopilot flight computer completes the pre-flight test.
(2) Disconnect the roll servo connector from the airplane harness.
(3) Apply a ground to pin K of the harness connector.
(4) Connect a digital multimeter across the harness connector at pins D and L to monitor the servo
drive voltage.
(5) Push the autopilot AP button on the autopilot flight computer to engage it.
(a) Make sure the default ROL mode is set.
NOTE:
(b)
(c)
(d)

Use a DMM to measure the DC voltage across pins D and L of the roll servo harness
connector.
Adjust the pot until a value of 0 volts, +0.020 or -0.020 volts are measured.
1
If the end of the pot movement is reached before the servo drive is nulled, disengage
the autopilot, turn the pot fully to the opposite stop and then engage the autopilot.
The roll null adjustment range emulates a four turn pot that lets the method of the pot
adjustment range to be set.
NOTE:

(6)
7.

For example, the HDG, NAV or APR modes are not engaged.

This adjustment lets offsets be in the roll axes.
coordinator.

This includes the turn

(e) Continue to turn the pot to null the voltage.
Connect the airplane roll servo harness connector to the servo connector.

KAP-140 Autopilot Controller Removal/nstallation
A.

Remove the Autopilot Controller (Refer to Figure 202).
(1) Make sure the AVIONICS and MASTER switches are in the off position.
(2) Loosen the mounting screw on the face of the autopilot controller.
(3) Move the autopilot controller aft and remove from the mounting tray.
(4) Disconnect the electrical connector and static line.

B.

Install the Autopilot Controller (Refer to Figure 202).
(1) Connect the electrical connector and static line.
(2) Put the autopilot controller in position in the mounting tray.
(3) Tighten the mounting screw on the face of the autopilot controller.
(4) Make sure the static system does not leak. Refer to Pitot/Static Systems - Maintenance
Practices.
(5) Do a test of the autopilot to make sure it operates correctly. Refer to Introduction, the List of
Manufacturers Technical Publications, for the manufacturer's installation manual.

22-10-00
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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(STANDARD EQUIPPED AIRCRAFT)
05B5T1040

A0585T140

KAP-140 Autopilot Installation
Figure 202 (Sheet 1)
22-10-00
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL '172
MAINTENANCE MANUAL

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(GARMIN G1000 EQUIPPED AIRCRAFT)
A0518T1109
B0518T1111

KAP-140 Autopilot Installation
Figure 202 (Sheet 2)

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MODEL 172
MAINTENANCE MANUAL
AUTOPILOT SERVO - INSPECTION/CHECK
1.

General
A.

2.

The autopilot on this aircraft uses a pitch servo, a pitch trim servo and a roll servo. This section will
give instructions for the inspection of the pitch, pitch trim, and roll servos. There is also an inspection
for the pitch trim rigging.

Roll Servo Inspection
A.

Do an Inspection of the Roll Servo (Refer to Figure 601).
(1) Remove the servo cover.

CAUTION: Make sure the maintenance personnel and the table are electrically
grounded.
Do disassembly or assembly of the servo at an
electrostatic-safe area.

(2)

(3)
(4)
(5)
3.

(a) Put an electrical ground on the maintenance personnel and table.
(b) Remove the two screws that attach the cover to the unit.
(c) Carefully remove the cover over the wiring harness.
(d) Put the servo on the table so the inner parts of the unit will not be damaged.
Do an inspection of the solenoid and clutch.
(a) Make sure the solenoid shaft moves freely in and out of the solenoid body.
(b) Make sure there is no dirt, contamination or corrosion around the solenoid shaft.
(c) Make sure the release spring freely pulls the shaft out of the solenoid and against the stop
fitting.
(d) Make sure the pinion gear turns and does not touch the clutch gears.
Do a general inspection of the roll servo.
(a) Examine the electrical wiring for indication of wear or damage of the insulation.
(b) Examine the servo for any loose hardware or other defects.
Install the cover.
(a) Carefully put the cover in position.
(b) Install the screws with Loctite 222 or Loctite 242.
Remove the servo capstan assembly and do a check of the slip-clutch torque setting (Refer to
Servo Capstan Clutch Adjustment).

Pitch Servo Inspection
A.

Do an Inspection of the Pitch Servo (Refer to Figure 601).
(1) Remove the servo cover.

CAUTION: Make sure the maintenance personnel and the table are electrically
grounded.
Do disassembly or assembly of the servo at an
electrostatic-safe area.
(a) Put an electrical ground on the maintenance personnel and table.
(b) Remove the two screws that attach the cover to the unit.
(c) Carefully remove the cover from the wiring harness.

CAUTION: Do not move any wires, tie wraps or the spring clamp. The
position of each Is set by the manufacturer and Is necessary
for correct operation.
(d) Put the servo on the table so the inner parts of the unit will not be damaged.
(2) Do inspection of the solenoid and clutch.
(a) Make sure the solenoid shaft moves freely in and out of the solenoid body.
(b) Make sure there is no dirt, contamination or corrosion around the solenoid shaft.

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MODEL 172

MAINTENANCE MANUAL

C

ROLL SERVO CONTROL
CABLE GUARD
(NOTE)
3L CABLE
LEG
AL)

0

1

CONTROL CABLE

L

D

L-

AILERON

LOCATION OF

D

COA/Ar-Cln DAI I

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VIEW A-A
TURNBUCKLE

ROLL SERVO

NOTE:

THE CONTROL CABLES MUST
NOT TOUCH THE CONTROL
CABLE GUARD LEGS

DETAIL A
0510T1007
A0560T1011
AA0760T1009

Autopilot Servo Inspection
Figure 601 (Sheet 1)

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MODEL '172
MAINTENANCE MANUAL

B240

CONTROL CABLE
GUARD LEG
(TYF

CONTROL CABLE

GUARD

CONTROL CABLES

VIEW B-B

CONTROL CABLE
CLAMP BLOCK
CABLE

CONTRC
CABLE A

SERVO

CLAMP BLC

B

DETAIL D

B0560T101B
BB0560T1019

Autopilot Servo Inspection
Figure 601 (Sheet 2)

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MODEL 172

MAINTENANCE MANUAL

B241

CONTROL CABLE
GUARD LEG
(TYPICAL)

CONTROL CABLE GUAR

VIEW C-C

C°

PD
PITCH TRIM SERVO

C
CON1

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CCo05OT1017

Autopilot Servo Inspection
Figure 601 (Sheet 3)

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MAINTENANCE MANUAL
Make sure the release spring freely pulls the shaft out of the solenoid and against the stop
fitting.
(d) Make sure the pinion gear turns and does not touch the clutch gears.
Do a general inspection.
(a) Examine the electrical wiring for indication of wear or damage of the insulation.
(b) Examine the servo for any loose hardware or other defects.
Do an inspection of the pitch servo motor.
(a) Put the servo in position so the baseplate is on the bottom side of the unit.
(b) Hold the top section of the motor and carefully turn the motor shaft.
(c) The motor shaft must turn freely from side to side a small quantity.
Install the cover.
(a) Carefully put the cover in position.
(b) Use screws with Loctite 222 or Loctite 242.
Remove the servo capstan assembly and do a check of the slip-clutch torque setting (Refer to
Servo Capstan Clutch Adjustment).
(c)

(3)
(4)

(5)
(6)
4.

Pitch Trim Servo Inspection
A.

Do an Inspection of the Pitch Trim Servo (Refer to Figure 601).
(1) Remove the servo cover.

CAUTION: Make sure the maintenance personnel and the table are electrically
grounded.
Do disassembly or assembly of the servo at an
electrostatic-safe area.

(2)

(3)
(4)
(5)
5.

(a) Put an electrical ground on the maintenance personnel and table.
(b) Remove the two screws that attach the cover to the unit.
(c) Carefully remove the cover over the wiring harness.
(d) Put the servo on the table so the inner parts of the unit will not be damaged.
Do inspection of the solenoid and clutch.
la) Make sure the solenoid shaft moves freely in and out of the solenoid body.
(b) Make sure there is no dirt, contamination or corrosion around the solenoid shaft.
(c) Make sure the release spring freely pulls the shaft out of the solenoid and against the stop
fitting.
(d) Make sure the pinion gear turns and does not touch the clutch gears.
Do a general inspection.
(a) Examine the electrical wiring for indication of wear or damage of the insulation.
(b) Examine the servo for any loose hardware or other defects.
Install the cover.
(a) Carefully put the cover in position.
(b) Install the screws with Loctite 222 or Loctite 242.
Remove the servo capstan assembly and check the slip-clutch torque setting (Refer to Servo
Capstan Clutch Adjustment).

Pitch Trim Rigging Inspection
A.

Do a check of the pitch trim rigging.
(1) Attach an inclinometer to the trim tab.
(2) Put the trim tab in the 0 degree position.
(3) Manually operate the trim tab to the up and down limits.
(4) Record the limits of travel.
(5) Put an observer at the right-hand access opening of the tailcone.
(6) Put the electrical trim to the full nose-up position until the observer sees the clutch slip.
(7) Turn the manual trim wheel nose-up (test load condition) 1/4 turn more while the clutch slips.
(8) Make sure the swaged ball on the control cable assembly does not turn aft of the tangent point.
(9) Release the trim wheel and disengage the autopilot.
(10) Manually operate the trim to the full nose-up position.
(11) Do a check of the trim tab position with an inclinometer.

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(12) Trim tab position that is greater than the limits of travel values recorded is an indication that the
stop blocks slipped.
(a) Do the trim system rigging again.
(b) Make sure the stop block bolts torque is correct.
(c) Repeat the check of the pitch trim rigging.
(13) If necessary, make adjustments to the swaged ball position.
(a) Put the control cable assembly chain in the applicable position on the gear teeth of the
actuator sprocket.
NOTE:

One chain link adjustment is related to approximately 17 degrees of travel on
the capstan.

(b) Apply the applicable tension to the control cable and repeat the check of the pitch trim
rigging.
(14) Do the procedure again for the full nose-down trim condition.

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CHAPTER

COMMUNICATIONS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

Page 1
Pages 201-209

Apr 7/2003

23-1 0-00
23-50-00

Pages 201-204

Jan 3/2005

23-60-00

Pages 201 -202

Apr 7/2003

23-Title
23-List of Effective Pages
23-Record of Temporary Revisions
23-Table of Contents
23-00-00

©Cessna Aircraft Company

23

-

Janl1/2007

LIST OF EFFECTIVE PAGES

Page 1 of 1
Janl1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
COMMUNICATIONS - GENERAL .........................
Scope ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tools and Equipment.............................
Definition ..................................
NAV/COM - MAINTENANCE PRACTICES .....................
General...................................
Troubleshooting ...............................
NAV/COM Radio Removal and Installation...................
GIA 63 Integrated Avionics Unit Removal/Installation ..............
VHF Antenna Removal/installation.......................
Microphone Switch Removal/installation....................
Microphone Switch Button Cleaning......................
AUDIO PANEL - MAINTENANCE PRACTICES ...................
General...................................
Troubleshooting ...............................
Audio Panel Removal/Installation .......................
Intercom Jacks Removal/Installation......................
Rear Passenger Intercom Jacks Removal/installation..............
STATIC WICKS - MAINTENANCE PRACTICES...................
General...................................
Tools and Equipment.............................
Static Wicks Removal/installation .......................
Bonding Straps Removal/installation......................

©Cessna Aircraft Company

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23 -CONTENTS

Pagel1 of 1
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
COMMUNICATIONS - GENERAL
1.

2.

Scope
A.

This chapter describes and provides maintenance instructions for equipment which furnishes a
means of communicating from one part of the airplane to another, and between the airplane and
other airplanes or ground stations

B.

Additional information on communications equipment can be found in the Wiring Diagram Manual
supplied with the airplane.

C.

Technical publications available from the manufacturer of the various components and systems which
are not covered in this manual must be utilized as required for maintenance of those components and
systems.

Tools and Equipment
NOTE:

Equivalent substitutes may be used for the following items:

NAME

NUMBER

MANUFACTURER

USE

Type I, Class B-2
Sealant

PR1440

Courtaulds Aerospace
5426 San Fernando Rd.
Glendale, CA 91209

To fay seal antenna to fuselage.

Bonding meter

Keithley Model 580

Keithley Instruments, Inc.
Instrument Division
28775 Aurora Rd.
Cleveland, OH 44139

To check electrical bonding
connections.

Megohmmeter

Model 2850

Associated
Research,
Inc.
3773 W. Belmont Ave.
Chicago, IL 60618

To check resistance of static
wicks.

3.

Definition
A.

Information contained in this chapter provides the basic procedures which can be accomplished at
the flight line level; such as, removal and installation of components and system operation.

B.

This chapter is divided into sections to aid maintenance personnel in locating information. A brief
description of each section is as follows:
(1) The speech communication section describes radio equipment used for reception and
transmission of voice communication.
(2) The audio integrating system section describes that portion of the system which controls
the output of the communications and navigation receivers into the pilot and passengers
headphones and speakers, and the output of the pilot's microphone into the communications
transmitters.
(3) The static discharging section describes the static discharge wicks used to dissipate static
electricity.

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MAINTENANCE MANUAL
NAV/COM

-

MAINTENANCE PRACTICES

1.General
A. Maintenance practices for the navigation/communications (NAV/COM) units have procedures for the
B.
C.

removal and installation of the different components.
The dual NAV/COM radio is in the instrument panel.
For airplanes with the Garmin G1000, the center of the Garmin G1000 is the GIA 63 Integrated
Avionics Unit (IAUI), which is in the tailcone. The GIA 63 operates as a primary communications
center that connects all of the Line Replaceable Units (LRUs) with the Primary Function Display (PFD)
and Multi-Function Display (MFD). The GIA 63 has the GPS receiver, VHF NAV/COM receivers, and
system integration microprocessors. The GIA 63W has the Wide Area Augmentation System (WAAS)
installed. The GIA 63 transmits directly to the PFD and MFD by a High-Speed Data Bus (HSDB)
Ethernet connection. Software and configurations are sent from the displays through the GIA 63 to
the LRUL's in the system.

2.

Troubleshooting
A. For troubleshooting procedures of the GIA 63 Integrated Avionics Units in airplanes with Garmin
G1lOQO, refer to the Garmin G1 000 Line Maintenance Manual.

3.

NAV/COM Radio Removal and Installation

NOTE:

The procedures that follow are for airplanes without Garmin G1lOCO.

CAUTION: Do not interchange the KX- 155A and KX- 165A NAV/COM Radios. You can
cause damage to the NAV/COM Radio.
A.

B.

4.

Remove the NAV/COM (Refer to Figure 201).
(1) Put the MASTER switch in the OFF position.
(2) Disengage the NAV/COM 1 and/or NAV/COM 2 circuit breaker.
(3) Turn the recessed mounting screw on the face of the NAV/COM unit counterclockwise until the
locking paw releases from the mounting tray.
(4) Move the NAV/COM unit aft out of the mounting tray to disconnect the electrical connectors
(PI1000, P11002, and P11004).
(5) Remove the NAV/COM unit from the mounting tray.
Install the NAV/COM (Refer to Figure 201).
(1) Put the NAV/COM unit in the mounting tray and move the unit forward.
(2) Connect the electrical connectors (PI1000, P11002 and P11004).
(3) Turn the recessed mounting screw on the face of the NAV/COM unit clockwise until the NAV/
COM unit is attached to the mounting tray.
(4) Engage the NAV/COM 1 and/or NAV/COM 2 circuit breaker.
(5) Put the MASTER switch in the ON position.
(6) Put the NAV/COM switch in the ON position.
(7) Do a check for correct operation.
(8) Put the MASTER and NAV/COM switches in the OFF position.

GIA 63 Integrated Avionics Unit Removal/Installation
NOTE:

The procedures that follow are for airplanes with Garmin G1000.

NOTE:
A.

The airplane has dual integrated avionics units installed. The removal/installation is typical.
Remove the Integrated Avionics Unit (Refer to Figure 202).
(1) Put the MASTER switch in the off position.
(2) Disengage the NAV/COM 1 and/or NAV/COM 2 circuit breaker.

0 Cessna Aircraft Company

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MAINTENANCE MANUAL

.11.
------ A

NAV/COM

NAWVC OM

DETAIL

A
0585T 1040
A0585T1040

NAV/COM Installation
Figure 201 (Sheet 1)

23-10-00
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MODEL 172

MAINTENANCE MANUAL

P-1

AIR DATA

TRANSPONDER

DETAIL

A

AIRPLANES THAT HAVE
THE GARMIN G1 000

0510T1007
A0518TI 103

Tailcone Avionics Installation
Figure 202 (Sheet 1)

23-10-00
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MAINTENANCE MANUAL
(3) Remove the aft seat to get access to the integrated avionics units. Refer to Chapter 25,
Passenger Compartment - Maintenance Practices.
(4) Remove the baggage compartment closeout to get access to the integrated avionics units. Refer
to Chapter 25, Interior Upholstery - Maintenance Practices.
(5) Disconnect the duct from the aft side of the unit. Refer to Avionics Cooling - Maintenance
Practices.
(6) Release the unit handle.
(a) For units with a Phillips screw, loosen the screw to unlock the unit handle.
(b) For units with a D-Ring, push on the D-Ring and turn it 90 degrees counterclockwise to
unlock the unit handle.
(7) Move the lever up to disengage the locking stud with the dog leg slot in the mounting rack.
(8) Remove the unit from the mounting rack.
B.

Install the Integrated Avionics Unit (Refer to Figure 202).
NOTE:

If the unit from the initial installation is installed in its initial position, it is not necessary to
load the software or configuration.

NOTE:

If the unit from the initial installation is installed in the opposite position, it is not necessary
to load the software but the units must be configured.

NOTE:

If a new unit is installed, the software and configuration must be loaded.

CAUTION: Make sure the unit goes into position without resistance. Damage to the
connectors, unit, or mounting rack will occur if the unit is pushed into
position with force.
NOTE:

The unit must be in position in the mounting rack to let the locking stud engage the channel.

(1) Make sure the connector and connector pins have no damage.
(a) Replace the connector or connector pins if applicable. Refer to the Wiring Diagram Manual
and the Garmin G1000 Line Maintenance Manual.
(2) Carefully put the unit in position in the mounting rack.

CAUTION: Make sure the lever moves without resistance. Damage to the unit
wilt occur it the lever is pushed into position with force.

C.

(3) Push the lever down toward the bottom of the unit to engage the locking stud with the dog leg
slot in the mounting rack.
(4) Lock the handle in position.
(a) For units with a Phillips screw, tighten the screw to lock the unit handle.
(b) For units with a D-Ring, push on the D-Ring and turn it 90 degrees clockwise to lock the
unit handle.
(5) Connect the duct to the aft side of the unit. Refer to Avionics Cooling - Maintenance Practices.
(6) Do a check for correct operation or configure the unit. Refer to Test and/or Configure Integrated
Avionics Unit.
(7) Install the baggage compartment closeout. Refer to Chapter 25, Interior Upholstery Maintenance Practices.
(8) Install the aft seat. Refer to Chapter 25, Passenger Compartment - Maintenance Practices.
Test and/or Configure Integrated Avionics Unit.
(1) Initial unit installed in initial position.
NOTE:

If the unit from the initial installation is installed in its initial location, it is not necessary
to load the software or configuration.

(a) Do a check to make sure the unit operates correctly. Refer to the Garmin G1000 Line
Maintenance Manual.

23-1 0-00
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MAINTENANCE MANUAL
(2)

Initial unit installed in the opposite location.
NOTE:

If the unit from the initial installation is installed in the opposite location, it is not
necessary to load the software but the units must be configured.

(a) Configure the units and do a check to make sure the units operate correctly. Refer to the
Garmin GlOQO0 Line Maintenance Manual.
(3) New unit installed.
NOTE:

If a new unit is installed, the software and configuration must be loaded.

(a) Load the software and configuration.
Manual.
5.

Refer to the Garmin G1000 Line Maintenance

VHF Antenna Remova~llnstallation
NOTE:

On airplanes with Garmin G1000 avionics, the left VHF antenna is also the GDL-69A antenna
and a GPS antenna.

NOTE:
A.

B.

The removal and installation procedures are typical for all VHF antennas.
Remove the VHF Antenna (Refer to Figure 203).
(1) Put the MASTER switch in the OFF position.
(2) Remove the four screws and washers that attach the VHF antenna to the upper surface of the
fuselage.
(3) Pull the antenna away from the fuselage to disconnect the coax connector from the antenna
(PC1 001 for VHF1 and P01 002 for VHF2).
Install the VHF Antenna (Refer to Figure 203).
(1) Connect the coaxial connector to the antenna (PC1001 for VHF1 and PC1002 for VHF2).
(2) Attach the antenna to the upper surface of the fuselage with the four screws and washers.

6.

Microphone Switch Removal/Installation
A.
Remove the Microphone Switch (Refer to Figure 204).
(1) Remove the nut that attaches the microphone switch (51) to the escutcheon.
(2) Remove the screw that attaches the escutcheon to the control wheel.
(3) Lift up the escutcheon to get access to the microphone switch and disconnect the microphone
switch from the control wheel connection.
B. Install the Microphone Switch (Refer to Figure 204).
(1) Connect the microphone switch (51) to the connection in the control wheel.
(2) Attach the microphone switch to the escutcheon with the nut.
(3) Set the escutcheon in position and install the screw in the escutcheon.

7.

Microphone Switch Button Cleaning
A. Clean the Switch Button (Refer to Figure 202).
NOTE:

Oil and dirt can collect on the internal electrical contacts of the switch and cause the button
to operate incorrectly.

(1) Apply a sufficient quantity of electrical contact cleaning spray around the full edge of the button
so it will soak down into the switch.
NOTE:

The electrical cleaner will help to remove oil and dirt from the internal electrical
contacts of the switch. The recommended contact cleaner is Electro Contact Cleaner
03116 or equivalent, which is supplied by LPS Laboratories, Inc. The phone number
is 1-800-241-8334.

© Cessna Aircraft Company

23-1 0-00

Page 205
Janl1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

'OME ANTENNA
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AIRPLANES WITH VHF ANTENNA
VHF Communication Antenna Installation
Figure 203 (Sheet 1)

23-10-00
©Cessna Aircraft Company

Page 206
Janl1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

MM84

VHF
ANTENNA

SCREW
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AIRPLANES WITH
GARMIN G1000
VHF Communication Antenna Installation
Figure 203 (Sheet 2)
© Cessna Aircraft Company

A051 8T1 107

23-1 0-00

Page 207
Janl1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

I
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Figure 204 (Sheet 1)

23-10-00
0 Cessna Aircraft Company

Page 208
Janl1/2007

0

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(2) Press the button many times to make sure the cleaner gets into the internal electrical contacts
of the switch.
(3) Complete an operational check of the switch.
NOTE:

The transmit light on the COM radio will come on when the power is turned on.

(4) If the button does not operate after the first application of the electric cleaner, apply more cleaner.
(5) If the button continues to operate incorrectly, replace the microphone switch. Refer to
Microphone Switch Removal/Installation.

© Cessna Aircraft Company

23-1 0-00

Page 209
Janl1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
AUDIO PANEL - MAINTENANCE PRACTICES
1.

2.

General
A.

The audio panel is in the center of the instrument panel. It has audio function, intercom function, and
marker beacon indicators in a single unit.

B.

On airplanes with Garmin G1000, the GMA 1347 audio panel is in the center of the instrument
panel between the Primary Flight Display (PFD) and Multi-Function Display (MFD). The GMA 1347
mixes NAV/COM digital audio, intercom system and marker beacon controls. The manual display
reversionary switch is on the GMA 1347.

C.

Maintenance practices for the audio panel have procedures for the removal/installation of the audio
panel and the intercom jacks.

D.

For removal/installation of the overhead speaker, refer to Chapter 25, Interior Upholstery Maintenance Practices.

E.

For removal/installation of the marker beacon antenna, refer to Chapter 34, Marker Beacon Maintenance Practices.

Troubleshooting
A.

3.

For troubleshooting procedures of the GMA 1347 Audio Panel, refer to the Garmin G1000 Line
Maintenance Manual.

Audio Panel Removal/Installation
NOTE:
A.

B.

The audio panel removal and installation is typical for all avionic configurations.
Remove the Audio Panel (Refer to Figure 201).
(1) Make sure the AVIONICS and MASTER switches are in the off position.
(2) Turn the recessed screw on the face of the audio panel counterclockwise until the locking paw
releases from the mounting tray.
(3) Carefully pull the audio panel out of the mounting tray.
Install the Audio Panel (Refer to Figure 201).
NOTE:

If a new audio panel is installed on airplanes with Garmin G1000, it is necessary to load
the software and configuration.

(1) Put the audio panel in position and move it forward into the mounting tray.
NOTE:

The audio panel must be installed correctly into the electrical connections at the back
of the mounting tray.

NOTE:

The recessed screw must not be tightened too much.

(2) Turn the recessed screw on the face of the audio panel clockwise until the audio panel is attached
to the mounting tray.
(3) Make sure the audio panel operates correctly.
(a) On airplanes without Garmin G1000, do a check to make sure the audio panel operates
correctly.
(b) If a new unit is installed on airplanes with Garmin G1000, load the software and
configuration. Refer to the Garmin G1000 Line Maintenance Manual.
(c) On airplanes with Garmin G1000, do a check to make sure that the audio panel operates
correctly. Refer to the Garmin G1000 Line Maintenance Manual.
4.

Intercom Jacks Removal/Installation
A.

Remove the Pilot/Front Passenger Intercom Jacks (Refer to Figure 201).
(1) Make sure the AVIONICS and MASTER switches are in the off position.
23-50-00
© Cessna Aircraft Company

Page 201
Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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23-50-00
© Cessna Aircraft Company

Page 202
Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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23-50-00
© Cessna Aircraft Company

Page 203
Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(2)
(3)
(4)
(5)
B.

5.

Remove the interior sidewall panel that is between the instrument panel and the forward doorpost
to get access to the back of the jack. Refer to Chapter 25, Interior Upholstery - Maintenance
Practices.
Remove the jam nut and washer that attaches the jack to the interior panel.
Put a label on the applicable wires of the microphone jack (small plug) and headphone jack
(large plug).
Cut the wires near the soldered joint of the applicable jack.

Install the Pilot/Front Passenger Intercom Jacks (Refer to Figure 201).
(1) Remove all unwanted solder from the jack.
(2) Solder the applicable wires to the jack. Refer to the Model 172 Wiring Diagram Manual, Chapter
20, Soldering - Maintenance Practices.
(3) Attach the jack to the sidewall panel with the jam nut and washer.
(4) Install the sidewall panel. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.

Rear Passenger Intercom Jacks Removal/Installation
A.

Remove the Rear Passenger Intercom Jacks (Refer to Figure 201).
(1) Make sure the AVIONICS and MASTER switches are in the off position.
(2) Remove the aft seat. Refer to Chapter 25, Passenger Compartment - Maintenance Practices,
Aft Seat Removal/Installation.
(3) Remove the rear sidewall panel. Refer to Chapter 25, Interior Upholstery - Maintenance
Practices.
(4) Put a label on the applicable wires of the microphone jack (small plug) and headphone jack
(large plug).
(5) Cut the wires near the soldered joint of the applicable jack.
(6) Remove the jam nut and washer that attaches the jack to the interior panel.

B.

Install the Rear Passenger Intercom Jacks (Refer to Figure 201).
(1) Remove all unwanted solder from the jack.
(2) Solder the applicable wires to the jack. Refer to the Model 172 Wiring Diagram Manual, Chapter
20, Soldering - Maintenance Practices.
(3) Attach the jack to the sidewall panel with the jam nut and washer.
(4) Install the rear sidewall panel. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(5) Install the aft seat. Refer to Chapter 25, Passenger Compartment - Maintenance Practices, Aft
Seat Removal/Installation.

23-50-00
© Cessna Aircraft Company

Page 204
Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
STATIC WICKS - MAINTENANCE PRACTICES
1.

2.

General
A.

Maintenance of the static (discharger) wicks consists of removal/replacement of the wick assembly
and ensuring that bonding straps are properly connected between control surfaces and primary
structure.

B.

Static wicks are mounted on the trailing edges of the ailerons, rudder and the elevators. Bonding
straps are secured to flight control surfaces and electrically connect those surfaces to the primary
structure.

Tools and Equipment
A.

3.

4.

For a list of applicable tools and equipment, refer to Communications - General.

Static Wicks Removal/Installation
A.

Remove Static Wick (Refer to Figure 201).
(1) Carefully drill out mounting rivets which attach static wick to structure. Ensure holes are not
drilled oversize.
(2) Remove static wick from the airplane skin.

B.

Install Static Wick (Refer to Figure 201).
(1) Clean surface of airplane skin where static wick will attach to skin. Remove all traces of
contaminants (including paint/primer) using scotchbrite and P-D-680 solvent.
(2) Secure static wick to airplane skin using rivets.
(3) Repaint at base of new wick (if required).
(4) Rebalance control surfaces. Refer to 1996 and On Single Engine Structural Repair Manual.

Bonding Straps Removal/Installation
A.

Bonding straps are provided to ensure that electrical potential between primary and secondary
structure remains nearly equal. If bonding straps are removed, they should be reinstalled using
hardware called out in the 172R Illustrated Parts Catalog.

B.

The maximum allowable resistance (in ohms) for bonding straps is 0.0025 ohms.

C.

Primary and secondary structure should be cleaned using scotchbrite pad and P-D-680 solvent
before installing bonding hardware. Aluminum surfaces should be chemically protected (alodine or
equivalent) before attaching bonding hardware to surface.

23-60-00
© Cessna Aircraft Company

Page 201
Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

I

D

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0518T1001
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Static Discharger Installation
Figure 201 (Sheet 1)

23-60-00
© Cessna Aircraft Company

Page 202
Apr 7/2003

CHAPTER

ELECTRICAL POWER

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

24-Title
24-List of Effective Pages
24-Record of Temporary Revisions
24-Table of Contents
24-00-00

Pages 1-2

Jul 3/2006

24-20-00

Pages 101-104

Jul 3/2006

24-20-00

Pages 201-202

Apr 7/2003

24-30-00

Page 101

Apr 7/2003

24-30-00

Pages 201-206

Apr 7/2003

24-30-10

Pages 201-205

Jan 2/2006

24-60-00

Pages 101-103

Jan 3/2005

24-60-00

Pages 201-204

Jul 3/2006

24-60-01

Pages 201-206

Jul 3/2006

24-61-00

Pages 201-203

Jul 1/2005

24-61-01

Pages 201-206

Jul 3/2006

24-70-00

Pages 1-3

Jan 2/2006

24 - LIST OF EFFECTIVE PAGES
© Cessna Aircraft Company

Page 1of 1
Jul 3/2006

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
ELECTRICAL POWER - GENERAL ...............................................

Scope......................................................................
Tools, Equipment and Materials ..............................................
ALTERNATOR - TROUBLESHOOTING ...........................................

24-00-00 Page 1
24-00-00 Page 1
24-00-00 Page 1

Troubleshooting .............................................................

24-20-00 Page 101
24-20-00 Page 101

ALTERNATOR - MAINTENANCE PRACTICES .....................................
General ....................................................................
Alternator Removal/Installation ...............................................

24-20-00 Page 201
24-20-00 Page 201
24-20-00 Page 201

.......................................

24-30-00 Page 101
24-30-00 Page 101

BATTERY - TROUBLESHOOTING .........

Troubleshooting .............................................................
BATTERY - MAINTENANCE PRACTICES .........................................

24-30-00
24-30-00
24-30-00
24-30-00
24-30-00
24-30-00
24-30-00
24-30-00

Page
Page
Page
Page
Page
Page
Page
Page

201
201
201
201
203
203
205
206

General ....................................................................
Standby Battery Removal/Installation .........................................
Standby Battery Printed Circuit Board Removal/Installation .....................
Standby Battery Charging....................................................
Standby Battery Storage.....................................................
Standby Battery Capacity Test ...............................................

24-30-10
24-30-10
24-30-10
24-30-10
24-30-10
24-30-10
24-30-10

Page
Page
Page
Page
Page
Page
Page

201
201
201
201
204
204
204

12-VOLT CABIN POWER SYSTEM - TROUBLESHOOTING.........................
General ....................................................................
Cabin Power Interface ......................................................
Power Converter............................................................

24-60-00
24-60-00
24-60-00
24-60-00

Page
Page
Page
Page

101
101
101
101

POWER JUNCTION BOX - MAINTENANCE PRACTICES...........................
General ....................................................................
Power Junction Box Removal/Installation......................................
Component Removal/Installation .............................................
Power Junction Box Troubleshooting .........................................

24-60-00
24-60-00
24-60-00
24-60-00
24-60-00

Page
Page
Page
Page
Page

201
201
201
201
201

ALTERNATOR CONTROL UNIT - MAINTENANCE PRACTICES.....................
General ....................................................................
Alternator Control Unit Removal/Installation ...................................
Over-voltage Protection Circuit Test...........................................
Alternator Control Unit Troubleshooting .......................................

24-60-01
24-60-01
24-60-01
24-60-01
24-60-01

Page
Page
Page
Page
Page

201
201
201
201
206

CIRCUIT BREAKER - MAINTENANCE PRACTICES ...............................
General ....................................................................
Circuit Breaker Removal/Installation (Airplanes without Garmin G1000) ..........
Circuit Breaker Removal/Installation (Airplanes with Garmin G1000).............

24-61-00
24-61-00
24-61-00
24-61-00

Page
Page
Page
Page

201
201
201
201

ESSENTIAL AND CROSSFEED BUS DIODES - MAINTENANCE PRACTICES .......
G eneral ....................................................................
Essential/Crossfeed Bus Diode Removal/Installation ...........................
Essential and Crossfeed Bus Diode Inspection ................................
Essential and Crossfeed Bus Diode Multimeter Test ............................

24-61-01
24-61-01
24-61-01
24-61-01
24-61-01

Page
Page
Page
Page
Page

201
201
201
201
206

General ....................................................................
Battery Removal/Installation .................................................
Battery Cleaning ............................................................
New Battery Check..........................................................
Battery Charging............................................................
Battery Test ................................................................
Battery Tray Flange Repair ..................................................
STANDBY BATTERY - MAINTENANCE PRACTICES Airplanes with Garmin G1000 ...

ELECTRICAL LOAD ANALYSIS - DESCRIPTION AND OPERATION ................
General ....................................................................

24-70-00 Page 1
24-70-00 Page 1

CONTENTS
© Cessna Aircraft Company

Page 1 of 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ELECTRICAL POWER - GENERAL

1.

Scope
A.

This chapter gives the electrical units and components which control and supply electrical power for
the airplane systems. This includes the alternator, batteries, and relays.

B.

Electrical energy for the airplanes is supplied by a 28-volt, direct current, single primary bus, negative
ground electrical system. A single 24-volt main battery supplies power to the starting system and gives
a reserve source of power if an alternator failure were to occur. Airplanes that have the Garmin G 1000
system have a second battery known as the Standby Battery. The Standby Battery is controlled and
monitored by the Standby Battery Controller and supplies power to the G1000 Essential Bus if there
is a failure of the main battery and alternator. A power junction box, also referred to as a Master
Control Unit (MCU), is attached to the forward left side of the firewall and includes electrical relays, an
alternator control unit (ACU), an ammeter sensor, an external power receptacle, fuses and/or circuit
breakers in a single box. An engine-driven alternator is the normal source of power during flight and
maintains a battery charge controlled by the ACU. The external power receptacle is used for ground
operation of the electrical equipment and helps the main battery during ground starts.

C.

Electrical power is supplied to the two primary electrical busses through two 30A fuses, two 30A circuit
breakers, or two 40A circuit breakers in the junction box. These electrical busses supply power to two
avionics busses through 15A circuit breakers. The two avionics busses are controlled by an avionics
master switch.

D.

The operation of the main battery and alternator system is controlled by the MASTER ALT BAT switch.
The switch is an interlocking split rocker and is found on the left side of the switch panel. The right
half of the rocker controls the main battery and the left half controls the alternator. It is possible
in this configuration for the main battery to be online without the alternator. However, operation of
the alternator without the main battery is not possible. The BAT MASTER switch, when operated,
connects the main battery contactor coil to ground so that the contacts close and supply power to the
system from the main battery only. The ALT MASTER switch, when ON, applies positive voltage to
the ACU and to the alternator contactor coil at the same time, which then applies field voltage to the
alternator field and supplies power to the electrical system from the alternator.

E.

The operation of the Standby Battery, if installed, is controlled by a three-position STDBY BATT switch.
Normal flight operation is with the switch in the ARM position that lets the standby battery charge from
the G1000 Essential Bus. If there is an alternator failure, the standby battery controller will not let the
standby battery discharge to the G1000 Essential Bus until the depletion or failure of the main battery.
It is necessary during preflight to do an "energy level" acceptance test. Refer to the Pilot's Operating
Handbook, Chapter 4, Starting Engine, for details of the "energy level" acceptance test.

F.

The main battery ammeter is controlled by a sensor found in the power junction box. In flight, without
the use of external power, the meter shows the quantity of current that flows to or from the battery.
With a low battery and the engine at cruise speed, the ammeter will show a large positive output and a
charge of the main battery. When the main battery is fully charged, the ammeter will show a minimum
charge rate.

G.

The main battery is a 24-volt, 12.75 Amp-hour (5-hour rate), flooded lead-acid type. The battery is
installed in the front-left side of the firewall.

2.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes can be used for the following items:

24-00-00
© Cessna Aircraft Comoanv

Page 1
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
NAME

NUMBER

MANUFACTURER

USE

Adhesive

41-30

Mid-West Industrial Chemical
Company
1509 Sublette
St. Louis, MO 63110

Used to bond the battery
vent drain tubes to the
battery case elbows.

Battery Charger

TDMC-81

Cessna Aircraft Company

Charges the battery.

Available Commercially

Cleans the battery.

John Fluke Mfg. Co.
6920 Seaway Blvd.
Everett, WA 98206

General electrical use.

Available Commercially

Measures the specific
gravity of electrolytes.

Lamar Technology Inc.
14900 40th Avenue North East
Marysville, WA 98271

To do the tests and
troubleshooting for
the J-box, (MCU) and
alternator systems.

Nonmetallic Brush
(Acid-Resistant)

Available Commercially

Cleans battery cells.

Rubber Gloves,
Rubber Apron, and
Protective Goggles.

Available Commercially

Give protection when you
clean the battery.

Small syringe

Available Commercially

Service of the battery.

Variable Power
Supply

Available Commercially

Supplies external power for
ground maintenance.

Cleaning Cloth
Digital Voltmeter

Model 87

Hydrometer (1.100
to 1.310 specific
gravity range)

I

MCU Test Set
(With instructions,
LI-0021)

TE04

12 Volt DC Power
Adapter

D02-0042

Cessna Aircraft Company
Cessna Parts Distribution
Department 701, CPD 2
5800 East Pawnee Road
Wichita, KS 67218-5590

Cabin Power System.
Commercial Airline
Connector adapts to
Automotive Power Port
Connector.

24-Volt Battery
Charger

TSC-01 V

Teledyne Continental Motors Battery
Products
840 West Brockton Avenue
Redlands, CA 92374
Phone: 1-800-456-0070

Charges the battery.

24-00-00
© Cessna Aircraft Company

Page 2
Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ALTERNATOR - TROUBLESHOOTING
1.

I

Troubleshooting
NOTE:

Refer to the Lamar TE04 MCU Test Set and the LI-0021 instructions for additional testing
procedures of the alternator system. Refer to Electrical Power - General, Tools, Equipment,
and Materials.

Engine not running
TROUBLE

PROBABLE CAUSE

REMEDY

ALTERNATOR FIELD CIRCUIT
BREAKER TRIPS WHEN
BATTERY AND ALTERNATOR
SWITCHES ARE TURNED ON

Shorted diodes in alternator

STEP 1: Turn off battery switch and
remove "B" lead (alternator feeder
wire) and filter capacitor lead
from BAT terminal on alternator.
If circuit breaker no longer trips
when alternator switch is turned
on, check filter capacitor for
short.
Replace filter capacitor
as necessary. If filter capacitor
is ok, and circuit breaker trips
when alternator switch is turned on,
reinstall the "B" lead and proceed
to step 2.

Short in alternator "B" lead.

STEP 2: Inspect "B" lead for short
to ground. Repair or replace "B"
lead as necessary. If no problem
with "B" lead is found, proceed to
step 3.

Short in alternator field winding.

STEP 3: Disconnect field wire from
FLD terminal on alternator. If circuit
breaker no longer trips, replace
alternator. Otherwise reinstall the
field wire and proceed to step 4.

Short in field wire.

STEP 4: Inspect field wire for short
to ground between alternator and
ACU. Repair or replace field wire as
necessary. If no problem with the
field wire is found, proceed to step
5.

Defective ACU.

STEP 5: Disconnect the ACU
connector in the J-box. If the circuit
no longer trips, replace the ACU.
Otherwise, reconnect the ACU
connector and proceed to step 6.

Short in alternator relay.

STEP 6:
Disconnect the red
wire from the small terminal of
the alternator relay. If the circuit
breaker no longer trips, replace
alternator relay.
Otherwise,
reinstall the red wire and proceed
to step 7.

24-20-00
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Engine not running
TROUBLE

PROBABLE CAUSE

REMEDY

Short in J-box wire.

STEP 7: Disconnect the PB018
J-box connector.
If the circuit
breaker no longer trips, look for
a short to ground in the red wire
that goes from pin C of JB018 to
the alternator relay and the ACU.
Repair and replace as necessary.
If nothing is found, proceed to step
8.

Short in wire between J-box and
alternator switch.

STEP 8: Look for a short in the
alternator switch wire between the
alternator switch and the J-box.
Repair and replace as necessary.
If nothing is found, proceed to step
9.

Defective circuit breaker.

STEP 9: Replace the alternator
field circuit breaker.

Defective ACU.

STEP 1:
Disconnect ACU
connector in J-box.
If circuit
breaker no longer trips, replace
ACU. Otherwise, proceed to step
2.

Short between field wire and
alternator "B" lead.

STEP 2: Look for short between
field wire and alternator "B" lead.
Repair or replace as necessary.

Broken lead on filter capacitor.

STEP 1: Repair or replace filter
capacitor.

Grounding problem.

STEP 2:
Check for proper
grounding at alternator, J-box, and
ground block. If ok, then check for
any loose connections in J-box or
alternator. If ok, proceed to step 3.

Engine running
ALTERNATOR FIELD CIRCUIT
BREAKER TRIPS WHEN
BATTERY AND ALTERNATOR
SWITCHES ARE TURNED ON.
(DOES NOT TRIP WHEN ENGINE
IS NOT RUNNING)

ALTERNATOR MAKES
ABNORMAL WHINING NOISE,
NOISE CHANGES PITCH WHEN
RPM CHANGES AND GOES
AWAY WHEN ALTERNATOR IS
TURNED OFF

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Engine not running
TROUBLE

LOW VOLTAGE LIGHT
DOES NOT GO OUT WHEN
ALTERNATOR AND BATTERY
SWITCHES ARE TURNED ON

PROBABLE CAUSE

REMEDY

Shorted diode in alternator.

STEP 3: Turn off battery switch
and remove cable from "BAT"
terminal of alternator. Disconnect
negative battery cable. Using a
digital multimeter with the diode
function selected, place negative
lead on "BAT" terminal of alternator
and positive lead on case or
"GND" terminal and a reading of
approximately 0.8 to 1.0 should be
seen. If a reading of about half
is seen then suspect a shorted
diode in alternator. Reverse the
test leads and the meter should
indicate an open circuit. If the
resistance function of the meter
is selected or if using older analog
meters the readings will be different
but one direction should yield
an open circuit and the other
a numerical value in very high
resistance (usually greater than 1
Megaohm). If using the resistance
function and a setting on very
high resistance (greater than 1
Megaohm), then the meter may
show leakage, although the diodes
are fine. Since the alternator has
an internal capacitor, readings
taken with meters selected on
resistance may be unstable.
If
readings are not ok, then replace
alternator.

Broken terminal on alternator "B"
lead.

STEP 1: Replace terminal on "B"
lead.

Defective ACU.

STEP 2: With engine running
and alternator switch on, check
bus voltage (bus voltage can be
ACU
displayed on the clock).
should turn low voltage light on
if voltage in J-box is at or below
24.5 volts. If light remains on and
clock displays at or above 26 volts,
replace ACU. Otherwise, proceed
to step 3.

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Engine not running
PROBABLE CAUSE

REMEDY

Loss of power to ACU and
alternator relay.

STEP 3: With engine not running
and alternator switch on, check
voltage at small terminal of
alternator relay where red wire
attaches. If zero volts, check for
open wire, defective alternator
switch, or defective alternator field
circuit breaker. If nothing is found,
proceed to step 4.

Defective relay.

STEP 4: With engine not running
and alternator switch on, check
for battery voltage at both large
If
terminals of alternator relay.
battery voltage is present at
only one large terminal, replace
Otherwise,
alternator relay.
proceed to step 5.

Defective alternator.

STEP 5: With engine not running
and alternator switch on, check
field voltage at FLD terminal of
alternator. Field voltage should
be approximately 2 volts less than
battery voltage. If field voltage is
ok, replace alternator. Otherwise,
proceed to step 6.

Open in field wire.

STEP 6: If there is no voltage
at FLD terminal, check for open
in field wire between alternator
and ACU. Repair or replace as
necessary. If nothing is found,
proceed to step 7.

Defective ACU.

STEP 7: Replace ACU.

AFTER ENGINE START WITH
ALL ELECTRICAL EQUIPMENT
TURNED OFF, CHARGE RATE
DOES NOT TAPER OFF IN 1-3
MINUTES

Defective ACU.

STEP 1: Check bus voltage. If 29
volts or higher, replace AC.U.

ALTERNATOR WILL NOT KEEP
BATTERY CHARGED

Alternator output voltage
insufficient.

STEP 1: This problem should be
accompanied by a low voltage
light that won't go out. Refer to
the section above concerning this
problem.

TROUBLE

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ALTERNATOR - MAINTENANCE PRACTICES

1.

General
A.

2.

A 60 amp alternator is installed on the forward side of the engine, below and to the right of the
crankshaft.

Alternator Removal/Installation
A.

B.

Remove Alternator (Refer to Figure 201).
(1) Remove upper and lower cowl.
(2) Disconnect battery cables.
(3) Disconnect electrical connectors from alternator.
(4) Remove safety wire from adjusting bolt. Remove bolt.
(5) Remove alternator mounting bolt.
(6) Remove drive Micro-V-Belt from alternator pulley.
(7) Remove alternator from airplane.
Install Alternator (Refer to Figure 201).
(1) Position alternator on mounting bracket and install mounting bolt and nut. Do not tighten at this
time.
(2) Place drive Micro-V-Belt on alternator pulley.
(3) Install adjusting bolt.

CAUTION: ANY AIRPLANE WITH A NEW ALTERNATOR BELT INSTALLED,
INCLUDING NEW AIRPLANES, BELT TENSION SHOULD BE
RECHECED WITHIN THE FIRST 10 TO 25 HOURS OF
OPERATION.
(4) Apply a torque wrench to the nut on alternator pulley and adjust the belt tension so the belt slips
at 7 to 9 foot-pounds of torque with a used belt, or 11 to 13 foot-pounds of torque with new
Micro-V-Belt.
(5) Torque the adjusting bolt to 160-185 inch-pounds and safety wire.
(6) Torque the alternator mounting bolt to 235-255 inch-pounds.

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B

ADJUSTING BOLT

ADJUSTMENT CAM

MICRO-V-BELT

ALTERNATO

CONNECTING LINK
NUT
BRA

ET ASSEMBLY

MOUNTING BOLT

0510T1007
A0550T1001

DETAIL A
Alternator Installation
Figure 201 (Sheet 1)

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BATTERY - TROUBLESHOOTING
1.

Troubleshooting

TROUBLE

PROBABLE CAUSE

REMEDY

BATTERY WILL NOT
SUPPLY POWER
TO BUS OR IS
INCAPABLE OF
CRANKING ENGINE

Battery discharged.

STEP 1: Place MASTER switch
and TAXI LIGHT switch in ON
position. Measure battery voltage
across battery terminals. A
normally charged battery will
indicate 23 volts or more. If
voltage is low, proceed to Step 2.
If voltage is normal, proceed to
Step 3.

Faulty battery.

STEP 2: Check fluid level in
battery cells and charge battery
at 28 volts for approximately 30
minutes or until the battery voltage
rises to 28 volts. If tester indicates
a good battery, the problem was
a discharged battery. If the tester
indicates a faulty battery, replace
the battery.

Faulty wiring or electrical connection
between battery terminal and master
switch.

STEP 3: With master switch
closed, measure voltage at
master switch terminal on bus bar
contactor. Normal indication is
zero volts. If voltage reads zero,
proceed to Step 4. If a voltage
reading is otained, check wiring
between battery terminal and
master switch. Also check master
switch.

Open coil on contactor.

STEP 4: Check continuity between
battery terminal and master switch
terminal on bus bar contactor.
Normal indication is 50 to 70
Ohms. If ohmmeter indicates an
open coil, replace contactor. If
ohmmeter indicates a good coil,
proceed to Step 5.

Faulty bus bar contacts.

STEP 5: Check voltage on bus
side of contact with master switch
closed. Meter normally indicates
battery voltage. If voltage is zero
or intermittent, replace contactor.
If voltage is normal, proceed to
Step 6.

Faulty wiring between battery terminal
and bus.

STEP 6: Inspect wiring between
contactor and bus. Repair or
replace wiring as necessary.

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MAINTENANCE MANUAL
BATTERY - MAINTENANCE PRACTICES
1.

General
A.

The battery is a 24-Volt, 12.75 Amp-hour or an optional heavy-duty 15.5 Amp-hour flooded lead-acid
type battery. Either of these batteries can be installed. The battery is installed on the front-left side of
the firewall below the electrical power junction box.
NOTE:

2.

The Amp-hour rate is based on a five hour discharge rate.

Battery Removal/Installation
A.

Remove the Battery (Refer to Figure 201).
(1) Remove the top engine cowl. Refer to Chapter 71, Cowls - Maintenance Practices.

CAUTION: DISCONNECT THE NEGATIVE BATTERY CABLE FIRST, THEN
THE POSITIVE CABLE. THIS WILL PREVENT AN ACCIDENTAL
SHORT OF THE BATTERY FROM HAND TOOLS.
Cut the tie straps to the positive terminal cover.
Disconnect the negative battery cable.
Disconnect the positive battery cable.
Disconnect the battery vent line at the hose clamp.
Remove the battery hold down bolts and washers.
Remove the cooling shroud from the battery.
Remove the battery from the airplane.
Install the Battery (Refer to Figure 201).
(1) Set the battery in the battery tray.
(2) Install the hold-down strap to the battery with the hold-down bolts.
(2)
(3)
(4)
(5)
(6)
(7)
(8)
B.

CAUTION: DO NOT TIGHTEN THE HOLD-DOWN BOLTS TOO MUCH OR
YOU WILL DAMAGE THE HOLD-DOWN STRAP.
(3) Tighten the hold-down bolts to 10 inch-pounds (1.13N.m).
(4) Connect the battery vent line with the hose clamp.

CAUTION: CONNECT THE POSITIVE BATTERY CABLE FIRST, THEN
CONNECT THE NEGATIVE CABLE. THIS WILL PREVENT AN
ACCIDENTAL SHORT OF THE BATTERY FROM HAND TOOLS.
(5)
(6)
(7)
(8)
(9)
3.

Connect the positive battery cable.
Install the positive battery terminal cover.
Attach tie-straps to the terminal cover.
Connect the negative battery cable.
Install the top engine cowl. Refer to Chapter 71, Cowls - Maintenance Practices.

Battery Cleaning
A.

Clean the Battery (Refer to Figure 201).
NOTE:

For correct operation, the battery and connections must be clean at all times.

(1) Remove the battery. Refer to Battery Removal/Installation.
(2) Tighten the battery cell filler caps to prevent the cleaning solution from entering the cells.
(3) Use a clean cloth moistened with a solution of bicarbonate (baking soda) and water to clean the
battery cable ends, battery terminals and the surfaces of the battery.
(4) Rinse with clear water.

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HOLD-DOWN BOLT

A

LE

CABLE

,NGE

DETAIL A
0510T1007
A0518T1023

Battery Installation
Figure 201 (Sheet 1)

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(5)
(6)
(7)
(8)
4.

New Battery Check
A.

5.

Use a dry cloth to clean off the water and let the battery dry.
Polish the cable ends and battery terminals with an emery cloth or a wire brush.
Install the battery. Refer to Battery Removal/Installation.
Apply petroleum jelly or an ignition spray product to the battery terminals to decrease corrosion.

Complete a New Battery Check.
(1) Do a specific gravity check to make sure the correct strength of electrolyte is used. The
electrolyte must be 1.285 +0.005 or -0.005 specific gravity when it is measured between 75F
to 85°F (24°C to 30°C).
(2) To charge a new battery, use the manufacturer's instructions supplied with the battery.
(3) Before you install the battery, clean the battery box. Refer to Chapter 12, Battery - Servicing.
(4) Install the battery in the airplane. Refer to Battery Removal/Installation.

Battery Charging
NOTE:

The procedures that follow are for batteries that use a Gill TSC-01V or a Gill TDMC Battery
Charger.

WARNING: YOU MUST KEEP SPARKS AND OPEN FLAME AWAY FROM THE
BATTERY. THE BATTERY MAKES HYDROGEN AND OXYGEN GASES
WHEN IT IS CHARGED. THE GASES WILL COLLECT AND CAUSE
A HAZARDOUS, EXPLOSIVE CONDITION. YOU MUST HAVE FREE
VENTILATION OF THE BATTERY AREA WHEN YOU CHARGE IT.
WARIING: THE BATTERY CELL TEMPERATURE MUST NOT BE MORE THAN
115°F (46°C). DECREASE THE CHARGE RATE IF THE TEMPERATURE
INCREASES MORE THAN 1-15°F(46°C). THE CHARGE MUST NOT
CAUSE ACID TO BE BLOWN FROM THE VENTS.
A.

If you use a Gill TSC-01V battery charger, do the instructions that follow.
NOTE:

The Gill TSC-01V is automated with a typical charge time of approximately two hours.
Some batteries will take more time to charge as a result of the battery condition.

(1) Remove the battery from the airplane and place it in a well ventilated area to charge. Refer to
Battery Removal/Installation.
(2) Remove the vent caps and make sure the electrolyte level is above the plates and separator
material. Do not fill the battery to the split rings at this time.
(3) Do a specific gravity check of the battery electrolyte with a hydrometer such as the Gill FR-1 (or
equivalent) to determine the battery charge. Refer to Table 201 and Table 202.
(4) Record the value for each battery cell.
(5) Install the vent caps.
(6) Attach the red cable to the positive battery terminal and the black cable to the negative battery
terminal.
(7) Connect the charger to AC power. The procedures that follow will result:
(a) The AC POWER ON indicator light will come on.
(b) The three battery level indicators will flash one time.
(c) The EMPTY battery level indicator will flash on and remain on.
NOTE:

The EMPTY battery level indicator shows that the battery is correctly connected.

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(8) If the battery is not fully charged, the PARTIALLY CHARGED indicator light will come on. Make
sure that the battery stays connected at this time.
NOTE:

Make sure that you let the battery fully charge. This will make sure of a good battery
life and performance.

(a) Do not disconnect the battery. The charger will not operate correctly if the battery is
disconnected and then connected after the PARTIALLY CHARGED indicator light comes
on. If the battery is disconnected, you must disconnect and connect the charger at the
electrical outlet to start the charge process.
(9) When the battery is fully charged, the BATTERY READY indicator will come on.
(10) The electrolyte level must touch the bottom of the split ring while the battery is warm and still on
the charger.
(a) If the electrolyte level needs to be increased, use only distilled or mineral free water
to adjust the electrolyte level. The battery must be warm when the electrolyte level is
increased.
NOTE:
(11)
(12)
(13)
(14)
(15)

B.

The electrolyte level decreases as the battery temperature decreases.

Do not add any more fluid after these instructions unless the battery electrolyte spills.
(a) If the fluid level is below the plates and separator material because a spill occurs, add
electrolyte with a value of 1.285 specific gravity.
When the BATTERY READY indicator light comes on, turn the AC power off.
Disconnect the battery charger from the electrical outlet.
Disconnect and remove the battery from the charger.
Do a specific gravity check of the battery electrolyte. Refer to Table 201 and Table 202.
(a) The specific gravity values between cells must not have a difference of more than 0.020.
(b) Acceptable specific gravity values that are adjusted for temperature, must be between
1.260 and 1.290.
(c) Ifthe battery does not give sufficient power to crank the engine with the starter, then replace
it with a new battery. Refer to New Battery Activation.

If you use a Gill TDMC battery charger, do the instructions that follow.
(1) Remove the battery from the airplane and place it in a well ventilated area to charge. Refer to
Battery Removal/Installation.
(2) Remove the vent caps and make sure the electrolyte level is above the plates and separator
material. Do not fill the battery to the split rings at this time.
(3) Do a specific gravity check of the battery electrolyte with a hydrometer such as the Gill FR-1 (or
equivalent) to determine the battery charge. Refer to Table 201 and Table 202.
(4) Record the value for each battery cell.
(5) Install the vent caps.
(6) Click the Gill TDMC charger ON button two times to select the 24 volt position.
(7) Set the timer for 8 to 10 hours.
NOTE:

The charger is in a constant current mode when the timer is on.

(8) Set the charge rate to 1.5 amps.

CAUTION: DO NOT LET THE BATTERY CHARGER CHARGE AT 32 VOLTS
FOR MORE THAN THIRTY MINUTES.
(9) Charge the battery until the voltage stabilizes for three consecutive hours or shows 32 volts,
whichever occurs first.
NOTE:

The charge is measured across the battery terminals with the charger on.

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(10) The electrolyte level must touch the bottom of the split ring while the battery is warm and still on
the charger.
(a) If the electrolyte level needs to increased, use only distilled or mineral free water to adjust
the electrolyte level. The battery must be warm when the electrolyte level is increased.
NOTE:

The electrolyte level decreases as the battery temperature decreases.

(11) Do not add any more fluid after these instructions unless the battery electrolyte spills.
(a) If the fluid level is below the plates and separator material because a spill occurs, add
electrolyte with a value of 1.285 specific gravity.
(12) Do a specific gravity check of the battery electrolyte. Refer to Table 201 and Table 202.
(a) The specific gravity values between cells must not have a difference of more than 0.020.
(b) Acceptable specific gravity values that are adjusted for temperature, must be between
1.260 and 1.290.
(c) Ifthe battery does not give sufficient power to crank the engine with the starter, then replace
it with a new battery. Refer to New Battery Activation.
6.

Battery Test
A.

Complete a Specific Gravity Check. Refer to Table 201 and Table 202.
(1) Measure the specific gravity of the battery with a hydrometer to find the condition of the battery
charge.
NOTE:

Some hydrometers will have a built-in temperature compensation chart and a
thermometer.

(2) The battery condition for various hydrometer values with an electrolyte temperature of 80°F
(27°C) is shown in Table 201.
(a) Electrolyte measurements with the hydrometer must be compensated for the temperature
of the electrolyte. Refer to Table 202.
NOTE:

For increased temperatures, the values will be lower.
temperatures, the values will be higher.

For decreased

(3) If the specific gravity indicates the battery is not fully charged, refer to Battery Charging.
NOTE:

For more accurate results, you can use a load type tester after you charge the battery.

NOTE:

A specific gravity check can be completed after the charge. This check will not find
cells that short circuit under electrical loads, or have broken connectors between cell
plates.

Table 201. Battery Hydrometer Values at 80°F (27°C).
VALUE

BATTERY CONDITION

1.280 Specific Gravity

100% Charged

1.250 Specific Gravity

75% Charged

1.220 Specific Gravity

50% Charged

1.190 Specific Gravity

25% Charged

1.160 Specific Gravity

Not Charged

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Table 202. Specific Gravity Correction to 80°(27°C)
ELECTROLYTE TEMPERATURE

ADD TO VALUE

140°F (60C)

1.024

130°F (54°C)

1.020

120°F(49°C)

1.016

110°F (43°C)

0.012

100°F (38°C)

0.008

SUBTRACT FROM VALUE

90°F (32C)
80°F (27°C)
70°F (21°C)
60°F (16°C)

0.008

50°F (10°C)

0.012

40°F (4°C)

0.016

30°F (-1C)

0.020

20°F (-7°C)

0.024

10°F (-12C)

0.028

0°F (-18°C)

0.032

-10°F (-23°C)

0.036

-20°F (-29°C)

0.040

-30-F (-34°C)

0.044

7.

Battery Tray Flange Repair
A.

Repair the Battery Tray Flange.
(1) If you find cracks on the bottom outboard battery tray flange, do the procedures that follow:

CAUTION: MAKE SURE YOU DO NOT CUT INTO THE FIREWALL
WHEN YOU CUT THE FLANGE OFF THE BATTERY TRAY.
(a) Remove the cracked flange from the battery tray.

Remove the screws that attach the left rudder bar shield and remove the rudder bar shield.
Pull the insulation up and away from the aft side of the firewall to get access to the battery
tray rivet.
(d) Drill the rivet that attaches the cracked battery tray flange to the firewall.
(e) Use an applicable rivet to plug the hole.
(f) Pull the insulation down against the aft side of the firewall.
(g) Install the left rudder bar shield.
(h) Flatten the area of the battery tray with a file and sandpaper where the flange was removed.
(i) Apply Alodine and paint to the repaired area. Refer to Chapter 20, Interior and Exterior
Finish - Cleaning/Painting.
(b)
(c)

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MAINTENANCE MANUAL
STANDBY BATTERY - MAINTENANCE PRACTICES
Airplanes with Garmin G1000
1.

General
A.

2.

3.

The maintenance procedures that follow have information for the removal, installation, capacity test
and how to charge the standby battery, which is installed behind the Primary Flight Display. If there is
no primary power source, the standby battery will give power to the essential bus for a period of time.
The standby battery PC board is installed on the back of the switch panel. The standby battery PC
board controls and monitors the release of electrical power to and from the standby battery.

Standby Battery Removal/nstallation
A.

Remove the Standby Battery (Refer to Figure 201).
(1) Make sure the STDBY BATT switch is in the OFF position.
(2) Make sure the MASTER ALT/BAT switch is in the OFF position.
(3) Remove the Primary Flight Display. Refer to Chapter 34, Garmin Display Unit - Maintenance
Practices.
(4) Disconnect the standby battery (UC005) electrical connector (P1).
(5) Remove the bolts and washers that attach the bracket to the bracket assembly.
(6) Carefully remove the standby battery from the airplane.

B.

Install the Standby Battery (Refer to Figure 201).
(1) Carefully put the standby battery (UC005) in the correct position on the tray.
(2) Set the bracket in the correct position on the top of the standby battery.
(3) Install the bolts and washers that attach the bracket to the bracket assembly.
(4) Connect the standby battery electrical connector (P1).
(5) Install the Primary Flight Display. Refer to Chapter 34, Garmin Display Unit - Maintenance
Practices.
(6) Turn the standby battery switch to the ARM position to make sure the standby battery and
essential bus voltage for the primary flight display operates correctly.

Standby Battery Printed Circuit Board Removal/nstallation
A.

Remove the Standby Battery Printed Circuit Board (PCB) (Refer to Figure 202).

CAUTION: Make sure you use a wrist strap when the standby battery PCB
is removed. The standby battery PCB is sensitive to electrostatic
discharge.

B.

(1) Make sure the STDBY BATT switch is in the OFF position.
(2) Make sure the MASTER ALT/BAT switch is in the OFF position.
(3) Remove the switch panel. Refer to Chapter 31, Instrument and Control Panels - Maintenance
Practices.
(4) Put on a wrist strap and ground the wrist strap to the airframe.
(5) Disconnect the standby PCB from the electrical connector (PI036).
(6) Remove the screws that attach the standby battery PC board (NZ001) to the extrusion.
(7) Carefully remove the board from the extrusion.
(8) If applicable, put the PC board in a electrostatic safe bag.
Install the Standby Battery PC Board (Refer to Figure 202).

CAUTION: Make sure a wrist strap is used when the standby battery PC board
is installed. The standby battery PC board is sensitive to electrostatic
discharge.
(1) Put on a wrist strap and ground the wrist strap to the airframe.
(2) Carefully install the PC board in the extrusion.
(3) Install the screws that attach the board to the extrusion.
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B

B

DETAIL A
AIRPLANES WITH GARMIN G1000 OPTION

BOLT

051rT1007
A0518T1109
B0518T1113

Standby Battery Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B

DETAIL A

AIRPLANES WITH GARMIN G1000 OPTION

EXTRUSION
SCREW
STANDBY BATTERY
TEST OVERHEAT
SWITCH (S1022)

STANDBY
TEST RESI
(R1010)

DETAIL

B

0510T1007
A0518T1109
B051 8T1116

Standby Battery Printed Circuit Board Installation
Figure 202 (Sheet 1)

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(4) Connect the board to the electrical connector (PI036).
(5) Install the switch panel. Refer to Chapter 31, Instrument and Control Panels - Maintenance
Practices.
4.

Standby Battery Charging
A.

Charge the Battery.
(1) Remove the battery from the airplane and put it in a well ventilated area to charge. Refer to
Chapter 24, Standby Battery - Removal/Installation.
(2) Connect the battery to the charger with the black, round Standby Battery Connector (P1). A
mating connector (JC032) can be purchased through Cessna. Refer to the Model 172R/172S
Wiring Diagram Manual - Chapter 24, Electrical Power.
NOTE:

To charge the standby battery, a constant voltage charger, constant current charger
or a modification of both can be used. Use only chargers that are made to charge
lead acid batteries. A constant voltage "fast" charge can be done with a charger that
has a DC voltage between 28.3 and 30.0. A "float" charge can be done with a charger
that has a DC voltage between 27.2 and 28.2.

CAUTION:

Never set the charger to a level that is higher than 30.0 volts or you
can cause damage to the battery.

(3) For a constant current charger, charge the battery. Refer to the charger's instructions.
NOTE:

There is no limit on the initial charge current as long as the voltage is not more than
30.0 volts. If it is necessary to set the charger to the battery capacity, use 8 amp-hour
as the standby battery capacity.

(4) For a constant voltage charger, charge the battery for up to 16 hours with a "fast" charge voltage
between 28.3 and 30.0 volts.
NOTE:

If the state of charge of the battery is satisfactory, charge times of less than 16 hours
are possible. The battery can be thought to be completely charged if the charge
current stays stable (approximately .1 to .2 amps) for a minimum of one hour. Charge
times of more than 16 hours can be done if the charge voltages are kept between the
recommended float charge range of 27.2 to 28.2.

(5) Install the battery. Refer to Standby Battery - Removal/Installation.
(6) Do the Standby Battery Energy Level Test described in the Pilot's Operating Handbook, Chapter
4 - Starting Engine Procedures. Make sure the green standby battery test light comes on and
stays on for the described time period.
5.

6.

Standby Battery Storage
A.

For the best battery life, the standby battery must be kept in a fully charged state when not in use.
This is true when installed on the aircraft and when in long term storage. To leave the battery in an
uncharged state for any given period of time will decrease the life of the battery. It is recommended to
charge the battery at a minimum of once every three months of inactivity. In warm climates, a more
frequent charge will be necessary.

B.

Prevent long term storage of the battery in a temperature environment greater than approximately
25°C. Sun shades that cover the aircraft deck skin that decrease the temperature of the battery are
recommended when the aircraft is parked in direct sunlight.

Standby Battery Capacity Test
A.

The battery capacity must be tested according to the time limits set forth in Chapter 5, Inspection Time
Limits. This test is also necessary to give the battery condition if the battery voltage decreases to less
than 20.0 volts such as in an unintentional deep discharge.

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MODEL 172
MAINTENANCE MANUAL
B.

Battery Capacity Test
(1) Make sure that the battery is fully charged before the capacity test is started. If the charge
condition is unknown, charge the battery. Refer to Chapter 24, Standby Battery Charging.
(2) Put the airplane in an area where there are high cabin light levels. Use sunlight or a well lit
hangar facility.
NOTE:

It is important that the photocell on the PFD controls the PFD light level to FULL
BRIGHT. The manual AVIONICS rheostat is not operational with the primary
alternator and main battery power turned off.

(3) Turn the STDBY IND rheostat to the full clockwise position.
NOTE:

A stopwatch will be necessary in the following steps to time the battery discharge.

(4) With the BAT/ALT MASTER switch in the OFF position, set the STDBY BATT switch to the ARM
position and immediately start the stopwatch.
(5) Make sure that all of the equipment on the essential bus operates correctly.
NOTE:

After initialization, the PFD will be functioning in full bright mode with only red X's over
the NAV 2, COM 2, and XPDR functions.

(6) Make sure that all the standby indicator lights come on.
(7) Make sure that the MFD and all the other electrical and avionic equipment on the primary busses
are not on.
(a) If the conditions in steps 6 through 8 are not met, stop the test and correct these conditions.
(b) Start at Step 1 when the condition has been corrected.
NOTE:

The standby battery initial current discharge will be between 2.1 and 3.1 amps as
shown on the PFD standby battery ammeter. The essential bus initial voltage will be
approximately 24.2 volts as shown on the PFD essential bus voltmeter.

(8) Continuously monitor the essential bus voltage as shown on the PFD essential bus voltmeter.
The battery capacity is satisfactory if the bus voltage stays more than 20.0 volts for 55 minutes.
(9) Set the STDBY BATT switch to OFF if the essential bus decreases to 20.0 volts or after a
minimum of 55 minutes.

CAUTION: Do not let the essential bus voltage decrease below 20.0 volts or
the standby battery can be damaged. Set the STDBY BATT switch
to the OFF position before the voltage drops to less than 20.0 volts.
Voltage values less than 22.5 volts can decrease quickly, so monitor
the voltage closely. If the voltage drops to less than 20.0 volts,
charge the battery immediately and do the test again.
NOTE:

If the standby battery voltage does not stay more than 20.0 volts for 55 minutes during
the standby battery capacity test, the battery is not acceptable for return to service.

(10) Charge the battery. Refer to Standby Battery Charging.

24-30-10
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MODEL 172

MAINTENANCE MANUAL
12-VOLT CABIN POWER SYSTEM - TROUBLESHOOTING
1.

2.

General
A.

The 12-Volt Cabin Power Outlet on the pedestal uses a power converter to convert 28-volt DC input
power to 13.8-volt DC output power. In airplanes with Garmin G1000 the power converter is in the
cockpit on the aft, right side of the firewall. The power converter in all other airplanes is in the tailcone.

B.

The converter output is used to power electrical devices that require a 12-volt power input. The
electrical connections are made with the use of a terminal block that is on the side of the converter.
The converter's output can be turned on and off by the use of the ON/OFF signal terminal on the
converter's terminal block. When 28 VDC is applied to this terminal, the converter will turn the output
on. When the 28 VDC is removed from the terminal, the output is turned off.

Cabin Power Interface
A.

3.

Complete a Test of the Cabin Power Interface (Refer to Figure 101).
(1) Make sure the ALT/BAT Master switch is in the ON position.
(2) For airplanes with serials 1728001 thru 17281142 and airplanes 172S8001 thru 172S9288, you
will have to use a 12-Volt DC power adapter to do the test. Refer to Tools, Equipment and
Materials.
(a) Attach the adapter to the cabin power system.
(3) Use a voltmeter to make sure the output shows 13.4 volts, +0.9 or -0.9 volts at the cabin power
interface.
(4) If the correct voltage is not shown, do the troubleshooting of the Power Converter.

Power Converter
A.

Complete a Test of the Power Converter (Refer to Figure 102 and to the Model 172 Wire Diagram
Manual, Chapter 24, Power Interface).
(1) Disconnect the connector (JI).
(2) Make sure there is approximately 24-Volts between VI+ and VI- at the aircraft side of the
connector (JI).
(3) Make sure there is approximately 24-Volts between the ON/OFF and VI- at aircraft side of the
connector (JI).
(4) If there is no voltage, make sure the wiring from the power convertor to the connector (JI) is not
damaged or has a bad connection.
(a) Repair or replace the connector (JI) or the wiring as necessary.
1
Attach the connector (JI).
2
Make sure the cabin power interface operates correctly. Refer to Cabin Power
Interface.
(5) If the cabin interface does not operate correctly, make sure the pins VO+ and VO- at the converter
have an output of 13.4 +0.9 or -0.9 volts.
(a) If the correct voltage is supplied, do a check of the continuity from the aircraft side of the
connector (J1) to the cabin power interface (JC022 automotive style) or (JC008 airline
style).
1
If the wire continuity is not correct or the wire is damaged, replace the wiring as
necessary.
2
If the wire continuity is correct, replace the power converter.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

A

TRIM
WHEEL

)

(
0o

PEDESTAL

CABIN
POWER
INTERFACE

COVER

0

AUDIO IN

I--

DETAIL

CABIN

POWER
INTERFACE

A

DETAIL

AIRPLANES 17280001 THRU 17281142 AND
AIRPLANES 172S8001 THRU 172S9288

A

AIRPLANES 17281143 AND ON AND
AIRPLANES 172S9289 AND ON

0510T1007
A0719T1031
A071 T 1032

Cabin Power Interface
Figure 101 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

D4AO4

NOTE:

THE POWER CONVERTER
CAN BE IN DIFFERENT
LOCATIONS. IN AIRPLANES
WITH GARMIN G1000 IT IS
IN THE COCKPIT ON THE
AFT, RIGHT SIDE OF THE
FIREWALL. IN AIRPLANES
WITH STANDARD AVIONICS
IT IS IN THE TAILCONE.

POWER CONVERTER

CONNECTOR

DETAIL A

0510T1007
A1260T1012

Power Converter
Figure 102 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
POWER JUNCTION BOX - MAINTENANCE PRACTICES
1.

General
A.

2.

Power Junction Box Removal/Installation
A.

Remove the Power Junction Box (Refer to Figure 201).
(1) Remove the upper cowl. Refer to Chapter 71, Cowls - Maintenance Practices.
(2) Disconnect the battery cables. Refer to Battery - Maintenance Practices.
(3) Remove the cover from the power junction box.
(4) Disconnect the electrical connectors, cables, and ground strap from the power junction box.
(5) Remove the bolts that attach the power junction box to the firewall.
(6) Remove the power junction box from the airplane.

B.

Install the Power Junction Box (Refer to Figure 201)
(1) Put the power junction box on the firewall and attach it with the bolts.
(2) Connect the electrical connectors, cables, and ground strap to the power junction box.
(3) Install the cover on the power junction box.
(4) Connect the battery cables. Refer to Battery - Maintenance Practices.
(5) Install the upper cowl. Refer to Chapter 71, Cowls - Maintenance Practices.

|1~

3.

The power junction box, also referred to as a Master Control Unit (MCU), is installed on the forward,
left side of the firewall. The power junction box has a battery relay, starter relay, alternator relay,
current sensor, external power relay, alternator control unit, power distribution bus, and bus fuses (or
circuit breakers as applicable).

Component Removal/Installation
A.

General Precautions and Notes.

CAUTION: Make sure that all electrical power is removed from the airplane
and that the battery is disconnected before work is done on power
junction box components.
(1) Components such as relays, current sensors, and the alternator control unit can be replaced
as necessary. Refer to the Model 172R/172S Illustrated Parts Catalog for replacement part
numbers.
(2) Before you disconnect the wires, identify them with labels for correct installation.
(3) Find the torque values for ground and conductive studs in Chapter 20, Torque Data Maintenance Practices.
4.

Power Junction Box Troubleshooting
A.

Complete the Power Junction Box Troubleshooting.
(1) The power junction box troubleshooting is done with the Lamar TE04 MCU Test Set. Use the
LI-0021 instructions. Refer to Electrical Power - General, Tools, Equipment, and Materials.

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MODEL 172

MAINTENANCE MANUAL

B1

BOLT

POWER
JUNCTION
BOX

A
EXTERNAL
ELECTRICAL
POWER

A

DETAIL

A
051 0T1007
A0558T1001

Power Junction Box Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1700

SE
MAIN
BATTERY
CURRENT
SENSOR

/

STARTER
RELAY (K2

BATTERY
RELAY (K3)

fff ffI

I I\\

-----

ELECTRICAL
CONNECTORS
(J1 AND J2)

VIEW A-A
AIRPLANES 17280001 THRU 17280983 AND
AIRPLANES 172S8001 THRU 172S8703
THAT DO NOT INCORPORATE SB00-24-01
0558T1002

Power Junction Box Installation
Figure 201 (Sheet 2)

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MODEL 172

MAINTENANCE MANUAL

B4006

ALTERNATOR
-^

tK1-T

Ir-

CIRCUIT
BREAKER

CIRCUIT
r'lrli

11T

DD-

A ICtD

ALTERNATOR
CONTACTOR
(K)
\

CLOCK
FUSE

0

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D

D
ST/
CO
(K2

[-l

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,

kj I /-luv1

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)R

Jo.)

VIEW A-A
AIRPLANES 17280984 AND ON AND
AIRPLANES 172S8704 AND ON AND
AIRPLANES INCORPORATING SB00-24-01

NOTE:

CS3100 CURRENT SENSOR SHOWN
CS3200 CURRENT SENSOR SIMILAR
FOR J-BOXES MC01-3A(IC10) AND ON.
AA0558T1007

Power Junction Box Installation
Figure 201 (Sheet 3)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ALTERNATOR CONTROL UNIT - MAINTENANCE PRACTICES
1.

General
A.

2.

Alternator Control Unit Removal/Installation
A.
B.

3.

The Alternator Control Unit (ACU) is found inside the power junction box, also referred to as a Master
Control Unit (MCU) or J-Box. The alternator system includes the ACU, Alternator Contactor, and
alternator field circuit. The ACU functions are as follows:
(1) Alternator Voltage Regulation - The ACU controls the alternator field circuit to supply a main bus
voltage of approximately 28.5 volts.
(2) Low Voltage Annunciation - The ACU monitors the main bus voltage in the power junction box
and supplies an output for low voltage (less than 24.5 +0.35 or -0.35 volts) for the annunciation.
(3) Over-voltage Protection - The ACU monitors the main bus voltage in the power junction box and
disengages the aircraft ALT FIELD circuit breaker. This removes the power from the alternator
system if there is an over-voltage condition greater than 31.75 +0.5 or -0.5 volts.
(4) Reverse Alternator Current Protection - The ACU monitors the alternator output current and
disengages the aircraft ALT FIELD circuit breaker. This removes the power from the alternator
system if there is a reverse alternator current.
(5) Excess Field Current Protection - The ACU monitors the alternator field current and disengages
the aircraft ALT FIELD circuit breaker. This removes the power from the alternator system if
there is an excessive field current.

Remove the Alternator Control Unit. Refer to Power Junction Box - Maintenance Practices,
Component Removal/Installation.
Install the Alternator Control Unit. Refer to Power Junction Box - Maintenance Practices, Component
Removal/Installation.

Over-voltage Protection Circuit Test
A.

B.

General.
(1) The ACU Over-voltage Protection Circuit must be tested in accordance with the time limits in
Chapter 5, Inspection Time Limits. Use one of the two procedures that follow to do the test of
the Over-voltage Protection Circuit. The recommended procedure uses the Lamar TE04 MCU
Test Set. The external battery procedure can be used if a TE04 test set is not available.
Over-voltage Protection Circuit Test with the Lamar TE04 MCU Test Set
(1) Use a Lamar TE04 MCU Test Set and do steps 4.2, 4.3.A, 4.3.B, and 4.3.1 in the Lamar's TE04
MCU Test Set instructions LI-0021(refer to Electrical Power - General, Tools, Equipment, and
Materials).
(2) If the ACU TRIP indicator on the TE04 MCU Test Set does not illuminate in step 4.3.1, the Overvoltage Protection Circuit is not operational.
(a) Replace the ACU.
(b) Do this test again.
(3) If the ACU TRIP indicator does illuminate in step 4.3.1, the Over-voltage Protection Circuit is
operational.
(a) Complete the Lamar procedure 4.3.1.
(b) Remove the TE04 MCU Test Set.
(c) Continue with step D in this section.

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MODEL 172

MAINTENANCE MANUAL
C.

Over-voltage Protection Circuit Test with External Batteries
NOTE:

It is necessary to use two general non-rechargeable 9 volt batteries in new condition to
apply a temporary over-voltage condition on the ACU Sense wire. A locally fabricated
battery test harness is also necessary. The test harness uses two 9-volt snap connectors
and two insulated alligator clips. (Refer to Figure 201.) These components are available
at most battery supply stores. For ground safety reasons, only general household 9 volt
batteries which have a relatively low ampere rating are used.

(1) Make sure the BAT MASTER, ALT MASTER, AVIONICS master, and all electrical system
switches are in the OFF position.
(2) Remove the upper cowl. Refer to Chapter 71, Cowls - Maintenance Practices.
(3) Disconnect the airplane 24 volt battery cables from the battery. Refer to Battery - Maintenance
Practices.
(4) Remove the cover from the power junction box.
(5) Find the orange ACU sense wire attached to the upper Battery Contactor terminal inside the
power junction box. Refer to Figure 201.
(a) Remove the nut, washer, and orange ACU sense wire ring terminal from the upper Battery
Contactor terminal.
NOTE:

The ACU sense wire is connected to Pin B in the ACU connector.

(6) Connect the battery test harness in series with the orange ACU Sense wire and the upper Battery
Contactor terminal as shown in Figure 201.
(a) Use tape or an equivalent as electrical insulation on the bare sense wire ring terminal.
NOTE:

This will help prevent accidental electrical shorts.

(7) Connect two new 9-volt batteries to the harness.
(a) Put the 9 volt batteries in position below the power junction box as shown in Figure 201.
(8) Connect the airplane 24 volt battery cables to the battery. Refer to Battery - Maintenance
Practices.
(9) Make sure the ALT FIELD circuit breaker on the pilot's circuit breaker panel is engaged.
(10) Put the BAT and ALT MASTER switches to the ON position for 5 seconds and then return to the
OFF position.
(a) Make sure the ALT Field circuit breaker opens or the cap pops out.
(b) If the circuit breaker opens, the Over-voltage Protection circuit is operational. Continue
with step 11.
(c) If the circuit breaker does not open, do step 10 a second time.
1
Use a digital voltmeter and measure the voltage between the orange ACU sense wire
ring terminal and the power junction box ground stud.
(d) If the circuit breaker does not open the second time and the ACU sense voltage is greater
than 34 volts, the Over-voltage Protection Circuit is not operational.
1
Replace the ACU.
(e) Do step 10 again after a new ACU is installed.
(11) Engage the ALT Field circuit breaker.
(12) Disconnect the airplane 24 volt battery cables from the battery. Refer to Battery - Maintenance
Practices.
(13) Disconnect the two 9-volt batteries from the harness.
(14) Disconnect the battery test harness.
(15) Install the nut, washer, and orange ACU sense wire ring terminal to the upper Battery Contactor
terminal.
(a) Torque the terminal nut from 35 to 45 inch-pounds.
(16) Install the cover on the power junction box.
(17) Connect the airplane 24 volt battery cables to the battery. Refer to Battery - Maintenance
Practices.
(18) Install the upper cowl. Refer to Chapter 71, Cowls - Maintenance Practices.
(19) Continue with step D in this section.

24-60-01
©Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

rower

El

WER
NCTION
X

A
EXTERNAL
ELECTRICAL
POWER
RECEPTACLE

0510T1007
AO55BT1001

Over-Voltage Protection Circuit Test with External Batteries
Figure 201 (Sheet 1)

24-60-01
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B6230

ALTERNATOR
CONTROL
UNIT

CIRCUIT
BREAKERS

G

yq]

(f]

Fl
Fl

ACU SENSE WIRE
) FROM UPPER
CONTACTOR
I LHMINAL)

0
VIEW A-A

AA0558T1007

Over-Voltage Protection Circuit Test with External Batteries
Figure 201 (Sheet 2)

24-60-01
© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B6231

INSULATED
ALLIGATOR
CLIP

INSULATED
Al I I

A-Tl-r,

'AI U

BLACK LEAD WIl
SPLICE
RED LEAD WIRE

LEAD WIRE (POS)
LEAD WIRE (NEG)

9 VOLT BATTERY
SNAP CNNNFCTC

9 VOLT BATTERY
SNAP CONNECTOR

DETAIL B

B0558T1007

Over-Voltage Protection Circuit Test with External Batteries
Figure 201 (Sheet 3)

24-60-01
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
D.

Make sure of the correct ACU functions immediately after the next engine start.
(1) Start the engine in accordance with the Pilot's Operating Handbook, Starting Engine (Using
Battery) procedure but make sure the ALT MASTER switch is in the OFF position.
(2) After the engine start and oil pressure check, set the engine RPM to idle.
(3) Make sure the Low Voltage annunciator is On.
(4) While you monitor the aircraft voltmeter, set the ALT MASTER switch to the ON position.
(a) If the voltmeter shows more than 29 volts, immediately set the ALT MASTER switch to the
OFF position and stop the engine.
NOTE:

The ACU regulation circuit is non operational. The ALT FLD circuit breaker
should open if the voltage is more than 32 volts.

1
Replace the ACU and do the Over-voltage Protection Test again.
If the voltmeter shows less than 29 volts, slowly increase the throttle to an engine speed
of 1300 RPM.
(5) If the voltmeter shows approximately 28 volts at an engine speed of 1300 RPM the ACU
regulation circuit is operational.
(6) Make sure the battery charge is shown on the aircraft battery ammeter.
(7) Make sure the LOW VOLTS annunciator is off.
(b)

4.

Alternator Control Unit Troubleshooting
A.

Complete the Alternator Control Unit Troubleshooting.
(1) The Alternator Control Unit troubleshooting is done with the Lamar TE04 MCU Test Set. Use
the LI-0021 instructions. Refer to Electrical Power - General, Tools, Equipment, and Materials.

24-60-01
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
CIRCUIT BREAKER - MAINTENANCE PRACTICES
1.

General
A.

B.

2.

3.

On airplanes without Garmin G1000, the circuit breaker panel is on the left lower instrument panel,
below the pilot's control wheel. The circuit breaker panel has electrical circuit breakers, the MAGNETO
switches, the ALT BAT MASTER switch, the AVIONICS MASTER switch and panel lighting controls.
On airplanes with Garmin G1000, the circuit breaker panel is on the left lower instrument panel, below
the pilot's control wheel. The circuit breaker panel has electrical circuit breakers and the MAGNETO
switches.

Circuit Breaker Removal/Installation (Airplanes without Garmin G1000)
A.

Remove the Circuit Breaker (Refer to Figure 201).
(1) Remove the top cowl. Refer to Chapter 71, Cowls - Maintenance Practices.
(2) Disconnect the battery cables. Refer to Battery - Maintenance Practices.
(3) Remove the screws that attach the circuit breaker panel to the lower instrument panel.
(4) Remove the screws that attach the circuit breaker cover to the panel.
(5) Put a label on the applicable circuit breaker wires.
(6) Disconnect the applicable circuit breaker wires.
(7) Remove the nut and washer that attach the circuit breaker to the circuit breaker panel.
(8) Remove the circuit breaker.

B.

Install the Circuit Breaker (Refer to Figure 201).
(1) Remove the labels and attach the wires to the applicable circuit breakers.
(2) Put the circuit breaker in the circuit breaker panel and attach with the washer and nut.
(3) Put the circuit breaker cover in position on the back of the panel and attach with the screws.
(4) Put the circuit breaker panel in position on the lower instrument panel and attach with the screws.
(5) Connect the battery cables. Refer to Battery - Maintenance Practices.
(6) Install the top cowl. Refer to Chapter 71, Cowls - Maintenance Practices.

Circuit Breaker Removal/Installation (Airplanes with Garmin G1000)
A.

Remove the Circuit Breaker (Refer to Figure 202).
(1) Remove the top cowl. Refer to Chapter 71, Cowls - Maintenance Practices.
(2) Disconnect the battery cables. Refer to Battery - Maintenance Practices.
(3) Remove the screws that attach the circuit breaker panel to the lower instrument panel.
(4) Cut the tie straps from the applicable circuit breaker cover and remove the cover.
(5) Put a label on the applicable circuit breaker wires.
(6) Disconnect the applicable circuit breaker wires.
(7) Remove the screws and washers that attach the bus bar to the circuit breakers.
(8) Remove the bus bar.
(9) Remove the nut and washer that attach the circuit breaker to the circuit breaker panel.
(10) Remove the circuit breaker.

B.

Install the Circuit Breaker (Refer to Figure 202).
(1) Attach the circuit breaker to the circuit breaker panel with the nut and washer.
(2) Attach the bus bar to the circuit breakers with the screws and washers.
(3) Remove the labels and connect the applicable wires to the circuit breaker.
(4) Put the tie straps around the circuit breaker panel cover and through the 0.20 inch (5.08 mm)
diameter holes to attach the cover.
(a) For the inboard cover, put one tie strap each between circuit breakers H1034 and H1035
and between circuit breakers H1036 and H1037.
(b) For the outboard cover, put one tie strap each between circuit breakers H1054 and H1058
and between circuit breakers H1055 and H1057.
(5) Attach the circuit breaker panel to the lower instrument panel with the screws.
(6) Connect the battery cables. Refer to Battery - Maintenance Practices.
(7) Install the top cowl. Refer to Chapter 71, Cowls - Maintenance Practices.

24-61-00
© Cessna Aircraft Company

Page 201
Jul 1/2005

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

81701

A
0

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SWITCH
0518T1003
A0518T1004
AA0518T 1005

VIEW A-A
Circuit Breaker Panel Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

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0510T1007
A051Tr1109
B0518T1109
AA051 Tr1114
BB0518T1115

Circuit Breaker Panel Installation
Figure 202 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ESSENTIAL AND CROSSFEED BUS DIODES - MAINTENANCE PRACTICES
1.

2.

3.

General
A.

Airplanes with Garmin G1000 have an essential bus and a crossfeed bus. Airplanes without Garmin
G1000 have only a crossfeed bus.

B.

The essential and crossfeed bus diodes are on the circuit breaker panel. The diodes give power to
the essential and crossfeed buses from the two primary buses and at the same time isolate the two
primary buses.

C.

For maintenance data on the power junction box, refer to Power Junction Box - Maintenance Practices.

Essential/Crossfeed Bus Diode Removal/Installation
A.

Remove the Essential or Crossfeed Bus Diode (Refer to Figure 201).
(1) Remove the circuit breaker panel. Refer to Chapter 24, Circuit Breaker - Maintenance Practices.
(2) Carefully remove the heat shrinkable tubing from the diode. Refer to the Model 172R/172S
Wiring Diagram Manual, Chapter 20, Heat Shrinkable Tubing - Maintenance Practices.
(3) Remove the solder from the wire and from the diode. Refer to the Model 172R/172S Wiring
Diagram Manual, Chapter 20, Soldering - Maintenance Practices.
(4) Remove the nut and the washer from the diode.
(5) Remove the diode.

B.

Install the Essential or Crossfeed Bus Diode (Refer to Figure 201).
(1) Put the diode in position on the circuit breaker panel.
(2) Attach the diode with the nut and the washer to the circuit breaker panel.
(3) Install the heat shrinkable tubing over the wire. Refer to Model 172 Wiring Diagram Manual,
Chapter 20, Heat Shrinkable Tubing - Maintenance Practices.
(4) Add solder to attach the wire to the diode. Refer to Model 172 Wiring Diagram Manual, Chapter
20, Soldering - Maintenance Practices.
(5) Apply heat to the heat shrinkable tubing with a heat gun until the tubing is tight around the wire
and diode. Refer to Model 172 Wiring Diagram Manual, Chapter 20, Heat Shrinkable Tubing Maintenance Practices.
(6) Install the circuit breaker panel. Refer to Chapter 24, Circuit Breaker - Maintenance Practices.

Essential and Crossfeed Bus Diode Inspection
NOTE:

When the diodes are replaced, the inspections that follow (3A, 3B, or 3C) are required to make
sure that all of the diodes operate correctly.

NOTE:

The Lamar TE04 MCU Test Set is used as an alternative to inspections 3A, 3B, or 3C. Refer to
the Lamar TE04 MCU Test Set, instructions LI-0021 steps 4.3.A through 4.3.E.

A.

Do an inspection of the crossfeed bus diodes. (Refer to Figure 201). The inspection procedure that
follows is for power junction boxes that have primary bus fuses. Do inspections of the essential and
crossfeed bus diodes in accordance with the time limits shown in Chapter 5, Inspection Time Limits.
NOTE:

Airplanes 17280984 and ON, Airplanes 172S8704 and ON, and Airplanes incorporating
SB00-24-01 do not use fuses in the power junction box.

CAUTION: Do not remove fuses with the MASTER BAT switch in the ON position.
(1)
(2)
(3)
(4)
(5)
(6)
(7)

Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the landing light, taxi light, and oil pressure annunciation come on.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Remove the screws that attach the power junction box cover.
Remove the power junction box cover.
Remove the fuse (F1). (Refer to Power Junction Box - Maintenance Practices, Figure 201).
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.

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Jul 3/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

1\r Q"

A
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0510T1007
A0518T1015
AA0518T1016

Essential Bus and Crossfeed Diode Inspection
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

(Ni

DETAIL
BUS

B
(IN

I - Z)

DIODE

NOTE 1: ESSENTIAL BUS DIODES
NOTE 2: CROSSFEED BUS DIODES
0510T1007
AO51 8T1109
B051 81112
C0718T1055

DETAIL C
Essential Bus and Crossfeed Diode Inspection
Figure 201 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(8)

(9)
(10)
(11)
(12)
(13)

(14)
(15)
(16)
(17)
B.

Make sure that the landing light and oil pressure annunciation come on. If the taxi light comes
on or the oil pressure annunciation does not come on, do a test of the crossfeed bus diodes with
the diode test function of a digital multimeter to find which diodes you must replace. Refer to
Essential and Crossfeed Bus Diode Multimeter Test.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Install the fuse (F1) in the power junction box. If the fuse is pitted, arced, or does not fit tightly
into the fuse receptacle, replace the fuse with one of the same type. Do not replace the fuse
with thinner blades.
Remove the fuse (F2). (Refer to Power Junction Box - Maintenance Practices, Figure 201).
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the taxi light and oil pressure annunciation come on. If the landing light comes
on or the oil pressure annunciation does not come on, do a test of the crossfeed bus diodes with
the diode test function of a digital multimeter to find which diodes must be replaced. Refer to
Essential and Crossfeed Bus Diode Multimeter Test.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Install the fuse (F2) in the power junction box. If the fuse is pitted, arced, or does not fit tightly
into the fuse receptacle, replace the fuse with one of the same type. Do not replace the fuse
with thinner blades.
If the diodes are replaced, do this test again to make sure that all diodes operate correctly.
Install the junction box cover with the screws.

Do an inspection of the crossfeed bus diodes. (Refer to Figure 201). The inspection procedure that
follows is for power junction boxes that have primary bus circuit breakers.
NOTE:

The inspection procedure that follows is for airplanes without Garmin G1000 avionics.

CAUTION: Do not remove bus wires from the circuit breakers with MASTER BAT
switch in the ON position.
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)

(10)
(11)
(12)
(13)
(14)
(15)
(16)

(17)

Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the landing light, taxi light, and oil pressure annunciation come on.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Remove the screws that attach the power junction box cover.
Remove the power junction box cover.
Remove the hex nut and lock washer that connect the bus wire to the circuit breaker (F1). (Refer
to Power Junction Box - Maintenance Practices, Figure 201).
Remove the wire terminal from the F1 circuit breaker stud that has a label of AUX and isolate
the end of the bus wire.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the landing light and oil pressure annunciation come on. If the taxi light comes
on, or the oil pressure annunciation does not come on, do a test of the crossfeed bus diodes
with the diode test function of a digital multimeter to find which diodes must be replaced. Refer
to Essential and Crossfeed Bus Diode Multimeter Test.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Install the bus wire to the circuit breaker (F1) terminal. Use the same hex nut and washer that
were removed.
Torque the nut to 20 inch-pounds to 25 inch-pounds (2.3 N-m to 2.8 N-m).
Remove the hex nut and lock washer that connect the bus wire to the circuit breaker (F2). (Refer
to Power Junction Box - Maintenance Practices, Figure 201).
Remove the wire terminal from the F2 circuit breaker stud with the label of AUX and isolate the
end of the bus wire.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the taxi light and oil pressure annunciation come on. If the landing light comes
on or the oil pressure annunciation does not come on, do a test of the crossfeed bus diodes with
the diode test function of a digital multimeter to find which diodes you must replace. Refer to
Essential and Crossfeed Bus Diode Multimeter Test.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.

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MODEL 172

MAINTENANCE MANUAL
(18) Install the bus wire to the circuit breaker (F2) terminal. Use the same hex nut and washer that
were removed. (Refer to Power Junction Box - Maintenance Practices, Figure 201).
(19) Torque the nut to 20 inch-pounds to 25 inch-pounds (2.3 N-m to 2.8 N-m).
(20) If you replaced the diodes, do this test again to make sure that all diodes operate correctly.
(21) Install the junction box cover with the screws.
C.

Do an inspection of the essential and crossfeed bus diodes. (Refer to Figure 201). The inspection
procedure that follows is for airplanes that have Garmin G1000 avionics.
CAUTION: Do not remove bus wires from the circuit breakers with the MASTER
BAT or the STDBY BATT switches in the ON position.
(1)
(2)
(3)
(4)

Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the STDBY BATT and the AVIONICS master switches are in the OFF position.
Make sure that the landing and taxi lights come on.
Make sure that a minimum of 20 volts shows on the primary flight display (PFD) for the main
and essential bus voltmeters.
NOTE:

(5)
(6)
(7)
(8)
(9)
(10)
(11)

(12)
(13)
(14)
(15)
(16)
(17)
(18)

(19)
(20)
(21)
(22)

A minimum of 20 volts shows that there is power to the crossfeed and essential buses.
The GEA-71 must be on to show the voltage of the crossfeed bus. If there are no red
X's on the engine indications, the GEA-71 is on.

Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Remove the screws that attach the power junction box cover to the power junction box.
Remove the power junction box cover.
Remove the hex nut and lock washer that connect the bus wire to the circuit breaker (F1). Keep
the hex nut and lock washer. (Refer to Power Junction Box - Maintenance Practices, Figure
201).
Remove the wire terminal from the F1 circuit breaker stud that has a label of AUX and isolate
the end of the bus wire.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the landing light comes on and the main and essential bus voltages show a
minimum of 20 volts on the primary flight display (PFD). If the taxi light comes on or the main
and essential bus voltages do not show a minimum of 20 volts, or the PFD does not come on, do
a test of the essential and crossfeed bus diodes with the diode test function of a digital multimeter
to find which diodes must be replaced. Refer to Essential and Crossfeed Bus Diode Multimeter
Test.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
Install the bus wire to the circuit breaker (F1) terminal. Use the same hex nut and washer that
was removed. (Refer to Power Junction Box - Maintenance Practices, Figure 201).
Torque the nut to 20 inch-pounds to 25 inch-pounds (2.3 to 2.8 N-m).
Remove the hex nut and lock washer that connects the bus wire to the circuit breaker (F2).
(Refer to Power Junction Box - Maintenance Practices, Figure 201).
Remove the wire terminal from the circuit breaker (F2) stud and isolate the end of the bus wire.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the ON position.
Make sure that the taxi light comes on and the main and essential bus voltages show a minimum
of 20 volts on the PFD. If the landing light comes on, or the main and essential bus voltages do
not show a minimum of 20 volts, or the PFD does not come on, do a test of the essential and
crossfeed bus diodes with the diode test function of a digital multimeter to find which diodes
must be replaced. Refer to Essential and Crossfeed Bus Diode Multimeter Test.
Set the MASTER BAT, TAXI LIGHT, and LAND LIGHT switches to the OFF position.
With the hex nut and lock washer, install the bus wire to the circuit breaker (F2) terminal. (Refer
to Power Junction Box - Maintenance Practices, Figure 201).
(a) Tighten the nut to a torque of 20 inch-pounds to 25 inch-pounds (2.3 to 2.8 N-m).
If the diodes are replaced, do this test again to make sure that all diodes operate correctly.
Install the junction box cover with the screws.

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MODEL 172
MAINTENANCE MANUAL

4.

Essential and Crossfeed Bus Diode Multimeter Test
NOTE:

Do the essential or crossfeed bus diode inspection procedure applicable to your airplane before
the test that follows is done. Refer to Essential and Crossfeed Bus Diode Inspection.

NOTE:

The test that follows must be done only if required by the essential or crossfeed bus diode
inspections. The replacement of all the essential/crossfeed diodes is an alternative to the test
procedure that follows.

A.

Do a test of the essential/crossfeed bus diodes.
(1) Remove the circuit breaker panel to get access to the essential and crossfeed bus diodes. Refer
to Circuit Breaker - Maintenance Practices.
(2) Remove the nut and washer from each diode. (Refer to Figure 201).
(3) Isolate the diode from the bus bar on the circuit breaker panel. Do not remove the heat shrink
or wire from the diode.
(4) Do a test of each diode with the diode test function of a Fluke 75, 77, or 87 digital multimeter (or
equivalent digital multimeter with a diode test function).
(a) Connect the negative (-) or common lead of the meter to the threaded part of the diode
and the positive (+) lead of the meter to the opposite end of the wire to which the diode is
soldered. If the diode operates correctly, it will be conductive of an electric current and the
meter will show the forward voltage drop of the diode (approximately 0.2 to 0.8 volts).
(b) Interchange the meter leads. Connect the positive (+)lead of the meter to the threaded part
of the diode and the negative (-) or common lead of the meter to the opposite end of the
wire to which the diode is soldered. If the diode operates correctly, it will not be conductive
of an electric current and the meter will give an open circuit indication. This indication on
the meter will be the same as if the leads are not connected.
(c) Replace each diode that does not give a satisfactory indication during the multimeter test.
Refer to Essential and Crossfeed Bus Diode Removal/Installation.
(5) Install the diodes that give a satisfactory indication during the multimeter test. Refer to Essential
and Crossfeed Bus Diode Removal/Installation.
(6) When you replace the diodes, do the applicable essential/crossfeed diode inspection (3A, 3B,
or 3C) again to make sure that all diodes operate correctly.
(7) Install the circuit breaker panel. Refer to Circuit Breaker - Maintenance Practices.

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MODEL 172
MAINTENANCE MANUAL
ELECTRICAL LOAD ANALYSIS - DESCRIPTION AND OPERATION
1.

General
A.

The tables give an electrical load analysis of some of the components used on the airplane.

Table 1. Components on all airplanes
Component

Draw at 24 VDC
(Amperes)

Draw at 28 VDC
(Amperes)

Landing Light (4596 Lamp)

7.65

8.93

Landing Light (4591 Lamp)

3.06

3.57

Landing Light (35 Watt HID)

1.65

1.41

Taxi Light (4587 Lamp)

7.65

8.93

Taxi Light (4626 Lamp)

4.59

5.36

Taxi Light (35 Watt HID)

1.65

1.41

Navigation Lights

2.65

3.1

Wing Anti-collision Lights (average value) (Qty. 2)

1.98

1.7

Beacon Light (peak value)

1.07

1.25

Under Wing Courtesy Lights (Qty. 2)

0.98

1.14

Pilot Overhead Light (1864 Lamp)

0.14

0.16

Pilot Overhead Light (LED Lamp)

0.02

0.02

Copilot Overhead Light (1864 Lamp)

0.14

0.16

Copilot Overhead Light (LED Lamp)

0.02

0.02

Passenger Overhead Light (1864 Lamp)

0.14

0.16

Passenger Overhead Light (LED Lamp)

0.02

0.02

Map Light

0.08

0.09

Instrument Light (2 and 3 inch round) (Each)

0.02

0.02

Pedestal Lights (Qty. 1)

0.04

0.05

Flap Motor

2.06

2.4

Fuel Pump

3.00

3.50

Pitot Heat

3.33

3.89

12V Cabin Power Converter (Peak 10A out)

6.33

5.42

Hourmeter

0.01

0.02

Battery Relay Coil

0.29

0.33

Start Relay Coil

0.85

N/A

Alternator Relay Coil

0.29

0.33

Alternator Field and ACU Power (Maximum)

1.63

1.9

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Page 1

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
Table 1. Components on all airplanes (continued)
ACU Bus Sense

0.02

0.02

Start Motor

86

N/A

Autopilot Computer (KAP 140)

0.58

0.5

Pitch Servo & Clutch

0.58

0.5

Pitch Trim Servo & Clutch

0.58

0.5

Roll Servo & Clutch

0.53

0.45

Turn Coordinator

0.27

0.33

ADF Receiver (KR 87)

0.6

0.52

Table 2. Components used only on airplanes that do not have Garmin G1000 installation
Component

Draw at
24 VDC
(Amperes)

Draw at 28 VDC
(Amperes)

Glareshield Light (Fluorescent)

0.86

1

Glareshield Light (LED)

0.17

0.2

Radio Lights

0.17

0.2

Annunciator Panel (All annunciations on)

0.35

0.3

Avionics Fan

0.43

0.5

Engine and Fuel Gauges

0.38

0.45

Audio Panel (KMA-26) (Maximum)

1.5

1.29

Audio Panel (KMA-28) (Maximum)

1.5

1.29

MFD (KMD-550)

0.93

0.8

GPS (KLN 89/89B)

1.45

1.25

GPS (KLN 94)

1.4

1.2

Transponder (KT 73) (Maximum)

1.07

1.25

Transponder (KT 76) (Maximum)

0.6

0.7

Altitude Encoder (SSD120)

0.2

0.23

HSI (KCS 55A) (Maximum)

1.46

1.25

#1 Nav/Comm (KX 155A) (Receive)

0.8

0.69

#1 Nav/Comm (KX 155A) (Transmit) (Maximum)

6

6

#2 Nav/Comm (KX 165A) (Receive)

0.8

0.69

#2 Nav/Comm (KX 165A) (Transmit) (Maximum)

6

6

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

Table 3. Components used only on airplanes that have Garmin G1000 installation
Component

Draw at
24 VDC
(Amperes)

Draw at 28 VDC
(Amperes)

Circuit Breaker Panel Light (LED)

0.07

0.08

Switch Panel Light (LED)

0.07

0.08

Avionics Panel Lights (MFD, PFD, A/P)

0.17

0.2

Throttle/Flap Panel Light (LED)

0.07

0.08

Standby Battery Main Volt Sense

0.001

0.001

Standby Battery Controller

0.007

0.008

Standby Battery Test

2

N/A

Main Bus Voltage Sense

0.001

0.001

Essential Bus Voltage Sense

0.001

0.001

Deck Skin Fan

0.28

0.33

PFD Fan

0.08

0.09

MFD Fan

0.08

0.09

#1 Comm (GIA 63) (Receive)

0.22

0.19

#1 Comm (GIA 63) (Transmit) (VSWR 3)

4.96

4.16

#2 Comm (GIA 63) (Receive)

0.22

0.19

#2 Comm (GIA 63) (Transmit) (VSWR 3)

4.96

4.16

#1 Nav (GIA 63)

0.94

0.8

#2 Nav (GIA 63)

0.94

0.8

PFD (GDU 1040)

1.46

1.25

MFD (GDU 1040)

1.46

1.25

AHRS (GRS 77)

0.29

0.25

Air Data Computer (GDC 74)

0.25

0.21

Engine/Airframe Unit (GEA 71)

0.2

0.17

Transponder (GTX 33)

1.17

1

Audio Panel (GMA 1347)

1.58

1.36

FIS (GDL 69A)

0.42

0.36

24-70-00
© Cessna Aircraft Company

Page 3

Jan 2/2006

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
Table 3. Nav III Equipped Electrical Load Analysis (Optional Equipment) (continued)
Blind Turn Coordinator (KAP 140)

0.27

0.32

A

FIS (GDL69A)

0.42

0.36

A

ADF (KR 87)

0.60

0.52

A

Note

Definition

A

Current draw is from vendor data maximum.

B

Current draw is from previous load analysis report.

C

Current draw is from measurements on conformed equipment.

D

Avionics panel lights includes autopilot and ADF displays.

G

Fuel pump current draw: 3.0 amp maximum at 24.0 volts.

H

12 volt cabin power convertor has a maximum rating and current limited to 10 amps out. This
equals approximately 5.50 amp input.

I

Alternator field current maximum of 1.9 with 60 amp alternator. This includes alternator control
unit power.

J

For calculation, 1 minute of transmission for every 10 minutes of flight. Antenna VSWR 1:3.

K

For calculation, Comm #2 will be in receive mode 100% of the time. Comm #1 and Comm #2
cannot transmit at the same time.

M

Hour meter average current = 0.015 amps.

N

Beacon light has a 50% duty cycle ON/OFF period.

O
P

12 volt cabin converter has a pilot operating handbook limitation that prevents use during takeoff
and landing. Converter OFF current = 0.10 amp.
Equipment can draw power from the essential bus (HI020) and/or the avionics Bus 1 (HI018).
For calculation of the alternator operation collums, It is given that all power is from the Avionics
Bus 1.

Q

It is given that the dimmer control turned to FULL BRIGHT.

R

Main battery only operational after these electrical loads are OFF: Alternator Master, Avionics
Bus 1 Master, All external lights, Comm #2, Nav #2, audio, and 12 volt cabin power.

S

For calculation, pitch trim servo and clutch are given to be on 25% of the time.

T

Wing Anti-Collision Light average current = 0.85 amps with peak current of 1.7 amps.

24-70-00
© Cessna Aircraft Company

Page 4

Jan 3/2005

CHAPTER

EQUIPMENT/
FURNISHINGS

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

25-Title
25-List of Effective Pages
25-Record of Temporary Revisions
25-Table of Contents
25-00-00
25-10-00

Page 1

Janl1/2007

Pages 201-208

25-10-10

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Janl1/2007
Janl1/2007

25-20-00

25-22-00

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Apr 7/2003

25-50-00

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Apr 7/2003

25-60-00

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Janl1/2007

25-60-01

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Janl1/2007

25-60-01

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Janl1/2007

25-60-02

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Jan11/2007

25-60-02
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25-60-10

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Jan11/2007

25-80-00

Pages 201 -203

Apr 7/2003

©Cessna Aircraft Company

25

-

Jul 3/2006

Janl1/2007
Jan11/2007

LIST OF EFFECTIVE PAGES

Page 1 of 1
Janl1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
EQUIPMENT/FURNISHING - GENERAL ......................
Scope....................................
Tools, Equipment and Materials........................
Definition ..................................

25-00-00
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FLIGHT COMPARTMENT - MAINTENANCE PRACTICES ..............
General ...................................
Seat Removal/installation...........................
Shoulder Harness Guide Removal/Installation .................
Seat Rail Removal/installation ........................
Shoulder Harness and Seat Belt Inspection ..................
Crew Shoulder Harness and Seat Belt Removal/Installation ...........
Map Compartment Removal/installation ....................
INFLATABLE RESTRAINT SYSTEM - MAINTENANCE PRACTICES Airplanes with
AMSAFE Inflatable Restraint System........................
General...................................
Inflatable Restraint System Component Cleaning................
Inflatable Restraint System Inspection.....................
Storage of Spares ..............................
AMSAFE Inflatable Restraint Disarm/Arm ...................
Inflatable Restraint System Removal/installation ................
Inflatable Restraint System Adjustment/Test ..................
Inflatable Restraint System Troubleshooting ..................
PASSENGER COMPARTMENT - MAINTENANCE PRACTICES ...........
General...................................
Aft Seat Removal/installation .........................
Seat Belt and/or Shoulder Harness Assembly Removal/Installation........
Seat Belt and Shoulder Harness Assembly Test.................
INTERIOR UPHOLSTERY - MAINTENANCE PRACTICES..............
General...................................
Cabin Panels Removal/installation.......................
Door Panels, Carpet and Rubber Mat Removal/Installation............
CARGO TIE-DOWNS - MAINTENANCE PRACTICES ................
General...................................
POINTER EMERGENCY LOCATOR TRANSMITTER - MAINTENANCE PRACTICES..
General...................................
Pointer ELT Removal/installation .................
II.....I
ELT Remote Switch Removal/Installation....................
ELT Antenna Removal/installation (Integral Base with Coaxial Cable).......
ELT Whip Antenna Removal/Installation ....................
ELT Battery Pack Removal/installation .....................
Pointer ELT Operational Test .........................
ARTEX C406-N EMERGENCY LOCATOR TRANSMITTER - MAINTENANCE
PRA CTIC ES
. ...
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General...................................
Artex C406-N ELT Removal/installation.....................
ELT Remote Switch Removal/Installation....................
ELT Rod Antenna Removal/Installation.....................
Buzzer Removal/installation..........................
ARTEX C406-N EMERGENCY LOCATOR TRANSMITTER - INSPECTION/CHECK ...
General...................................
Artex C406-N ELT Functional Test.......................

©Cessna Aircraft Company

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25 - CONTENTS

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Janl1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
ARTEX ME406 EMERGENCY LOCATOR TRANSMITTER SYSTEM
AND OPERATION ................................
General...................................
Description .................................
Operation..................................

-

DESCRIPTION
25-60-02
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25 60 02
25-60-02

ARTEX
ME406
EMERGENCY
LOCATOR
TRANSMITTER
SYSTEM
TROUBLESHOOTING ..............................
General...................................
Tools and Equipment.............................
ME406 Emergency Locator Transmitter Self Test Preparation ..........

-

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MAINTENANCE PRACTICES........

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CARBON MONOXIDE DETECTOR - MAINTENANCE PRACTICES .........
111
General ...........................
Carbon Monoxide Detector Removal/Installation ................
SOUNDPROOFING AND INSULATION
General...................................

25 - CONTENTS
©Cessna Aircraft Company

1
1
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ARTEX ME406 EMERGENCY LOCATOR TRANSMITTER SYSTEM - MAINTENANCE
PRACTICES ...................................
General...................................
Emergency Locator Transmitter (ELT) Removal/Installation ...........
ELT Buzzer Removal/Installation .......................
Remote Switch Removal/Installation......................
ELT Antenna Removal/Installation.......................
ARTEX ME406 EMERGENCY LOCATOR TRANSMITTER (ELT) SYSTEM
INSPECTION/CHECK...............................
General...................................
Tools and Equipment.............................
Artex ME406 Emergency Locator Transmitter (ELT) Inspection..........
Artex ME406 Emergency Locator Functional Test................

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Page 2 of 2
Janl1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
EQUIPMENT/FURNISHING

-

GENERAL

1.Scope
A. This chapter describes the interior equipment and furnishings used throughout the airpiane. The
emergency locator transmitter and the carbon monoxide detector information is also included in this
chapter.
2.

Tools, Equipment and Materials
NOTE:

I

Equivalent substitutes may be used for the following listed items:

NAME

NUMBER

MANUFACTURER

USE

Aeroflex
Communications
Test Set

IFR 4000

Aeroflex, Wichita Division
10200 West York Street
Wichita, KS 67215-8935

To complete the
functional test of the Artex
ELT ME406 Emergency
Locator Transmitter.

Spray Adhesive

Airtac2

Advanced Materials Group
2542 East Del Amno Blvd.
Box 6207
Carson, CA

To adhere soundproofing
and insulation to fuselage
structure.

V23 System
Diagnostic Tool

508668-201

Cessna Aircraft Company Cessna
Parts Distribution, Department
701, 5800 East Pawnee Road
Wichita, KS 6721 8-5590

Test of the inflatable
restraint system.

SARSAT Beacon
Test Set

453-0131

Artex
P0 Box 1270
Canby, OR 97013

To complete the
functional test of the
Artex ELT.
To test the ELT.

30-dB Attenuator
3.

Definition
A. The chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief definition of the subjects
and sections incorporated in this chapter is as follows:
(1) The section on Flight Compartment covers those items installed in the cabin area, including
seats, seat restraints systems, carpets and interior panels.
(2) The section on emergency equipment covers the emergency locator transmitter installed behind
the aft baggage compartment. It also covers the carbon monoxide detector installed forward of
the instrument panel on airplanes that are equipped with Garmin G1000.
(3) The section on soundproofing and insulation covers the material used to deaden sound
throughout the airplane.

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Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
FLIGHT COMPARTMENT

-

MAINTENANCE PRACTICES

1.General
A. This maintenance practices section gives the removal and installation for the crew seats, seat
rails, seat belts, and shoulder harnesses. The seat belt and shoulder harness components are
non-repairable field items. You must replace any component that does not operate correctly.

WARNING: If the airplane has AMSAFE inflatable restraints, do not do
maintenance on the crew seats, seat rails, seat belts, or shoulder
harnesses until you first look at and obey all applicable precautions
and instructions supplied in AMSAFE publications and this
maintenance manual. If you do not obey these instructions and
safety precautions, damage to equipment and harm to personnel
can occur.
B.

2.

If your airplane has the AMSAFE inflatable restraint system, do not do maintenance on the seats
or the seat restraint system unless you first obey all applicable precautions and instructions in
the E508804 Supplemental Amsafe Maintenance Manual and this Maintenance Manual. Refer to
Inflatable Restraint System - Maintenance Practices.

Seat Remova~l/nstallation
A. Seat Removal (Refer to Figure 201).

WARNING: If the airplane has AMVSAFE inflatable restraints, do not remove
seats with the seat belts buckled or the EMA connected. Damage
can occur to the system and an accidental deployment of the
system can cause injury.
*

~~(1)

B.

Disarm the AMSAFE Inflatable Restraints. Refer to AMSAFE Inflatable Restraint Disarm/Arm.
(2) Remove the seat stops from the forward and aft of each seat track.
(3) Unlatch the seat from the seat track and move the seat forward on the seat track until the forward
roller clears the seat track.
(4) Move the seat aft on the seat track until the aft rollers clear the seat track.
(5) Remove the seat from the airplane.
Seat Installation (Refer to Figure 201).
(1) Set the aft roller of the seat in position on the seat track.
(2) Move the seat forward on the seat track until you can install the front roller on the seat track.
(3) Install the seat stops to the front and the rear of the seat track.

WARNING: Make sure the seat stops are set correctly. Incorrectly installed
seat stops can let the seat move during flight, with the result
of serious injury or death.
(4) Make sure the seat stops are installed correctly.
(5) Arm the AMVSAFE Inflatable Restraints. Refer to AMSAFE Inflatable Restraint Disarm/Arm.
(6) Complete a test of the seat through the full range of motion to make sure of the correct operation.
3.

Shoulder Harness Guide Removal/installation
NOTE:
A.

The removal/installation procedures are typical for the pilot and copilot seats.
Shoulder Harness Guide Removal (Refer to Figure 201).
(1) Move the seat in the full forward position.
(2) Put the seat back in the forward position.

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MAINTENANCE MANUAL

HEADREST

SHOULDER

HEIGHT
ADJUSTIt
CRANK

ASSEMBLY

E

DETAIL

A
0510T1007
A0519T1036

Seat Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

8219

BOLT

NUT PLATE
C

FLOORBOARD

N

SEAT
RAIL

BOLT

DETAIL
SPACER

B

WARNING: YOU MUST MAKE SURE THAT THE STOPS FOR THE SEATS ARE
INSTALLED CORRECTLY. THE MOVEMENT OF THE AIRPLANE CAN LET
THE SEAT DISENGAGE FROM THE SEAT RAILS WHICH WILL CAUSE
A DANGEROUS SITUATION.

B051 1T1 01

Seat Installation
Figure 201 (Sheet 2)
0 Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

6114

WASHERS
CYLINDER
LOCK

-IER
BOLT
WASHERS

DETAIL

C

WASHERS
FORWARD

BUSHING

R
AFT

HALVI-b

1

DETAIL

D

~BUSHING

ROLLER

DETAIL

E
C0519T 1037
D0519T1037
E05 19T1 039

Seat Installation
Figure 201 (Sheet 3)

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MAINTENANCE MANUAL
CAUTION: Make sure you are careful when you lift up the upholstery so you
do not cause damage.
(3) Lift the upholstery above the pocket on the seat back to get access to the headrest frame and
cotter pins.
(4) Remove the cotter pins from the headrest frame.
(5) Lift the headrest up and out of the seat back.
(6) Remove the shoulder harness guide.
(7) If you do not install a new shoulder harness guide, do the procedures that follow.
(a) Install the headrest into the seat back.
(b) Install new cotter pins in the headrest frame.

CAUTION: Make sure you are careful when you pull down the upholstery
so you do not damage it.

B.

(c) Pull down the upholstery over the seat back.
(d) Move the seat aft and set the seat back in the vertical position.
Shoulder Harness Guide Installation (Refer to Figure 201).
(1) If the seat is not in the same position as it was when the shoulder harness guide was removed,
complete the procedures that follow.
NOTE:

If the seat headrest is removed from the seat back, go on to the next step. You do
not have to complete this step.

(a) Move the seat in the full forward position.
(b) Put the seat backs in the forward position.

CAUTION: Make sure you are careful when you lift the upholstery so you
do not cause damage.
(c)

(2)
(3)
(4)
(5)

Lift the upholstery above the pocket on the seat back to get access to the headrest frame
and cotter pins.
(d) Remove the cotter pins from the headrest frame.
(e) Lift the headrest up and out of the seat back.
Install the shoulder harness guide on the headrest.
Install the headrest with the shoulder harness guide into the seat back frame.
Install new cotter pins in the headrest frame.
Move the seat aft and set the seat back in the vertical position.

CAUTION: Make sure you are careful when you pull down the upholstery so
you do not cause damage.
(6) Pull down the upholstery over the seat back.
(7) Move the seat aft and set the seat back in the vertical position.
4.

Seat Rail Removal/installation
A. Seat Rail Removal (Refer to Figure 201).
(1) Remove the bolts that attach the seat rails to the fuselage.
B. Seat Rail Installation (Refer to Figure 201).
(1) Install the seat rails to the fuselage with bolts.

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MAINTENANCE MANUAL

5.

Shoulder Harness and Seat Belt Inspection
A.

6.

The shoulder harness and seat belt assembly must be inspected in accordance with the time intervals
in Chapter 5, Inspection Time Limits. The shoulder harness and seat belt assemblies have a time life
associated with them. Refer to Chapter 5, Component Time Life for these limits.

Crew Shoulder Harness and Seat Belt Remova~l/nstallation
NOTE:
A.

B.

The removal and installation of the shoulder harness and seat belt assembly are typical.

Shoulder Harness and Seat Belt Assembly Removal (Refer to Figure 202).
(1) If necessary, disconnect the AMSAFE components as follows (refer to the applicable Warnings
and steps inlnflatable Restraint System - Maintenance Practices, Inflatable Restraint System
Removal/Installation):
(a) Disarm the AMVSAFE inflatable restraints.
(b) Disconnect the squib connector from the inflator assembly.
(c) Disconnect the gas hose from the inflator assembly.
(2) Remove the access covers (if installed) to get access to the attached hardware.
(3) Remove the nuts, bolts, washers, and spacers that attach the shoulder harness and seat belt
assembly to the fuselage and to the seats.
(4) Remove the shoulder harness and seat belt assembly from the airplane.
Shoulder Harness and Seat Belt Assembly Installation (Refer to Figure 202).
(1) Install the shoulder harness to the fuselage and/or the seat belt assembly to the seat.
(a) Make sure the spacers (if installed) are in the correct position.
(2) Install the access covers (if equipped).
(3) If necessary, connect the AMSAFE components as follows (refer to the applicable Warnings
and steps in Inflatable Restraint System - Maintenance Practices, Inflatable Restraint System
Removal/Installation):
(a) Connect the gas hose to the inflator assembly.
(b) Attach the squib connector to the inflator assembly.
(c) Arm the AMSAFE inflatable restraints.
(4) Complete a check of the system for the correct installation and operation.

7.

Map Compartment Removal/installation
A. Map Compartment Removal (Refer to Figure 203).
(1) Remove the interior screws that attach the map compartment to the instrument panel.
(2) Pull out the map compartment from the instrument panel.
B.

Map Compartment Installation (Refer to Figure 203).
(1) Put the map compartment in the instrument panel.
(2) Attach the map compartment to the instrument panel with the screws.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
B109

ANTI-CHAFE
PLATE
NTE

A

BOLT

B

DETAIL

PLUG BL
WA

HARNESS

Wi

DETAI
NUT
SEA:

DETAIL

C

C
L

1007
1046
1047
C051 9T1047B
01219T1001

I PIa-f-

Seat Belts and Restraints Installation
Figure 202 (Sheet 1)

©Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

81702

A
H-S

MAP
COMPARTMENT

SCREW

DOUBLER

HINGE

PIN
UUMrPdiI MLN I

DOOR

LAC
LATCH

DETAIL

A
A051 93003

Map Compartment Installation
Figure 203 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
INFLATABLE RESTRAINT SYSTEM - MAINTENANCE PRACTICES
Airplanes with AMVSAFE Inflatable Restraint System
1.General
A. This section has maintenance information for the AMVSAFE Aviation Inflatable Restraint (AAIR). The
AAIR is a self-contained, modular, three-point restraint system that will help to protect occupants from
head-impact injury during an accident. The AAIR system has four core components: the air bag
assembly, the inflation assembly, the electronics module assembly (EMVA), and the cable interface
assembly.

WARNING: Do not try to open the inflator assembly. Do not apply an electric
current to the electronics connection. The inflator assembly is
a stored, gas/energetic material device and can cause injury if
accidentally deployed.
2.

Inflatable Restraint System Component Cleaning
A. AMVSAFE recommends that the AAIR components be cleaned on a regular (annual) basis. Buildup
of dirt and unwanted material can cause problems with system operation, decrease the life of the
system, and help cause corrosion of the metal parts in the system. Glean the belt assembly, hoses,
cables, inflation device/cap assembly, and the EMVA.

CAUTION: Use care to keep contamination and cleaning agents away from the
hardware assemblies.
CAUTION: Do not let any part of the AAIR soak in any solution. This can cause
damage to the AAIR system. Do not use too much water when you
clean the AAIR parts. Too much water can cause damage to the internal
components and cause them to be unserviceable.
CAUTION: Only use sufficient cleaning agent to make minimal suds. Excess soap
must be removed before the part is installed in the system. Do not dry the
belt assembly in sunlight or near any source of heat. Do not dry clean
the belt assembly. Do not put the belt assembly fully into water.
CAUTION: Keep the isopropyl alcohol away from the webbing, air bag cover, and
the gas hose material.
CAUTION: Do not use soap or water on metal parts.
(1) Clean non-metallic parts with warm water and a household soap/laundry detergent and a moist
cloth.
(2) Flush the parts with clear water on a clean cloth.
(3) Use a soft brush, and cold soap solution to clean the webbing, air bag cover, and gas hose by
hand. Use a household liquid soap or detergent.
(4) Let the belt assembly dry by air.
(5) Clean any spacers, washers, nuts, or bolts with a lint-free cloth and isopropyl alcohol.
(6) Cover the cable opening into the EMVA with pieces of cloth. Clean the inflator and cables by hand
with a lint-free cloth and a cold water and mild soap solution.

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MODEL 172
MAINTENANCE MANUAL

3.

Inflatable Restraint System Inspection
The AMSAFE Aviation Inflatable Restraint (AAIR) must be examined in accordance with the time
intervals in Chapter 5, Inspection Time Limits. The AMSAFE Aviation Inflatable Restraint (AAIR)
assemblies have a time life associated with them. Refer to Chapter 5, Component Time Life for
these limits.
Do an inspection of the AAIR system parts.
(1) Air bag assembly.
(a) Make sure that the attachments are tightly connected.
(b) Do a visual inspection for dirt, oil, grease or other unwanted material.
(c) Do a check for wear on the edges of the belt.
(d) Do a check for damage on stitching or fabric threads.
(e) Do a check for holes or rub marks on the air bag cover.
(f) Do a check of the end fittings, buckle and connector for cracks, dents, or corrosion.
(2) Inflator hose.
(a) Do a check for fraying, wear, or tears.
(3) Cable interface assembly.
(a) Make sure all attachments are tightly connected.
(4) Inflator assembly.
(a) Do a check for loose mounting hardware.
(b) Do a check of the hose connection.
(c) Do a check of the electrical connection.
(5) Electronics module assembly (EMA).
(a) Do a check for loose connections and mounting hardware.

NOTE:

A.

4.

Storage of Spares
A.

Inflator Assembly.
NOTE:

The maximum continuous storage time for the inflator assembly is seven years from the
date of manufacture. After seven years, send the inflator assembly to AMSAFE Aviation
for inspection and repair.

(1) Keep the inflator assembly in a cool and dry area. The permitted temperature range is -300 C
(2) Keep the inflator assembly away from sunlight, dust, moisture, and other contamination.
(3) Keep the inflator assembly away from high electromagnetic, radio frequency, and electrostatic
environments.
(4) Obey all local storage regulations.
B.

Electronics Module Assembly (EMA).
NOTE:

The maximum continuous storage time for the EMA is seven years from the date of
manufacture. After seven years, send the EMVA to AMSAFE Aviation for inspection and
repair.

(1) Keep the EMA assembly in a cool and dry area. The permitted temperature range is -300 C to
+550

C.

(2) Make sure that the EMA is kept away from sunlight, dust, moisture, and other contamination.
(3) Keep the inflator away from EMI/RFI/ESD environments.
(4) Obey all local storage regulations.
C.

Air Bag Assembly.
(1) Keep the air bag assembly in a cool and dry area. The permitted temperature range is -300 C
(2) Make sure that the air bag assembly is kept away from sunlight, dust, moisture, and other
contamination.

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MAINTENANCE MANUAL

5.

AMSAFE Inflatable Restraint Disarm/Arm
A. Disarm the AMSAFE Inflatable Restraints.
(1) Make sure all seat belts are unbuckled.
(2) Find the end-release connector at the seat base.
(3) Remove the tie straps that attach the cable and end-release connector.
(4) Disconnect the end-release connector to disable the inflatable restraint.
B. Arm the AMSAFE Inflatable Restraints.
(1) Connect the end-release connector.
(2) Attach the cable and end-release connector to the seat frame with tie wraps.

6.

Inflatable Restraint System Remnova~l/nstalIlation

WARNING: Keep all magnetic fields away from the electronics module assembly
(EMA) during the removal and installation procedure. Accidental
deployment of the system can cause injury.
A.

Restraint System Removal. Refer to Figure 201.

WARNING: Do not remove seats from the airplane with the seat belts buckled
or the EMA connected. Damage can occur to the system and an
accidental deployment of the system can cause injury.
WARNING: Do not connect the EMA to the cable interface assembly unless
the EMA is first mounted to the airplane structure. Accidental
deployment can cause injury.
*

~~(1)

Disarm the AMSAFE inflatable restraints. Refer to AMSAFE Inflatable Restraint Disarm/Arm.
(2) Disconnect the squib connector from the inflator assembly.
(3) Disconnect the gas hose from the inflator assembly.
NOTE:

(4)
(5)
(6)

The gas hose barb has a layer of Loctite and is tightly attached to the fitting. Use
soft-grip channel locks to hold the barb while you disconnect the hose.

Loosen the clamps on the inflator-assembly mounting bracket.
Remove the inflator assembly from the mounting bracket.
Put shipping caps on the inflator-hose connector fitting. Refer to Table 201.

Table 201. Torque Values and Tool Sizes
PART DESCRIPTION
Inflator Shipping Cap

RELATED
SUBASSEMBLY
Inflator Assembly

TOOL AND SIZE

TORQUE (IN-LBS.)

Torque Wrench (In-lb.
5 - 10
type)
Hose Connection to
Air Bag Assembly/Inflator
Torque Wrench (In-lb.
110 - 130
the Inflator
Assembly
type)
(7) Remove the inertia reel (three-point air bag belt) from the airplane. Refer to Chapter 25, Flight
Compartment - Maintenance Practices.
(8) Remove the end-release buckle assembly from the airplane. Refer to Chapter 25, Flight
Compartment - Maintenance Practices.
(9) Disconnect the cable interface assembly from the EMA.
(a) Push down on the locking clip on the EMA connector and pull on the connector.
(10) Remove the cable interface assembly from the airplane.

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MAINTENANCE MANUAL

A
SEAT BACK
BUSHING
BOLT
WASHER

WA~c

___SEAT BACK

SQUIBG

Tr) Pi 1C(VI IP

IOLT
TIE S5
MOUNTIN
BRACKET

WASHER
INFLATOR
HOSE (TO AIR
BAG BELT)

INFLATOR
ASSEM BL

DETAIL

B

ND-RELEASE
,ONNECTOR
ECTRONICS MODULE
VIBLY (EMVA)
BOARD

DETAIL

051 OT1007
A0519T1004
B051 4T1056
CO0i 9T1074

C

AMVSAFE Aviation Inflatable Restraint System
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B3916

H

I

BOLT

WASHER

DETAIL
FO CREW SEATS

CABLE INTERFACE

FRONICS
JLE
MIBLY

TIE STRAP

(trv

%A

DETAIL

E

D
DIAGNOSTIC
CONNECTOR

C'l^j

END

Hun

-

RELEASE

TO INFLATOR
ASSEMBLY

0'~U ID

CONNEI

INFLATOR
HOSE

DETAIL

INFLATOR
ASSEMBLY

F

TO
BUCKLE
CABLE INTERFACE
ASSEMBLY
INFLATOR
ASSEMBLY
END

-

INFLAT OR HOSE
(TO AI R BAG BELT)

F

CON NE(

D0719T1 009
E0514T1 049
F071 9T1039
G0514T1 050

DETAIL U
AMSAFE Aviation Inflatable Restraint System
Figure 201 (Sheet 2)
©D
Cessna Aircraft Company

25-1 0-1 0

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MODEL 172
MAINTENANCE MANUAL

B6058

L-i

-j

LEFT HAND
CHILD SEAT ADAPTER

RIGHT HAND
CHILD SEAT ADAPTER

BU
SEAT BELT

a

B
SPACER

BO01-

SEAT BELT
BUCKLE
WASHER

WASH ER

WASHER

I

WASHER

DETAIL H

BENCH SEAT
NUT
H051 4T1 054

AMSAFE Aviation Inflatable Restraint System
Figure 201 (Sheet 3)

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MAINTENANCE MANUAL
(11)

B.

Remove the EMA from the airplane.
(a) Remove the nuts, washers and bolts that attach the EMA to the floorboard.
(b) Carefully remove the EMA from the airplane.
Restraint System Installation. Refer to Figure 201.
NOTE:
(1)

Leave the protective plastic bag on the air bag belt during installation to keep it clean.

Remove and keep the shipping caps from the inflator-hose connector fitting.
NOTE:

The shipping caps can be used again.

(2)

Put the inflator assembly into the mounting bracket. Do not tighten the clamps on the mounting
bracket.
(3) Remove and discard the end cap plug (if new) from the three-point air bag belt hose. Do not
remove the safety cable tie for the air bag connector tongue.
NOTE:

(4)

If the three-point air bag belt is not new and the inflator is new, apply a thin layer of
Loctite 242 thread locking compound on the hose barb threads before you attach the
inflator assembly.

Make sure that the three-point seat belt air bag belt is aligned correctly.
NOTE:

If aligned correctly, the gas hose will be on top of the seat belt attachment hardware.
The label will be on aft side of the belt.

(5) Connect the gas hose from the three-point air bag belt to the inflator assembly with the correct
torque. Refer to Table 201.
NOTE:
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)

(15)
7.

The inflator hose connector fitting is a pressure fitting which must be fully extended
onto the gas hose barb to make an airtight connection.

Attach the squib connector to the inflator assembly.
Tighten the clamps on the mounting bracket to between 21 and 25 inch-pounds of torque.
Attach the EMA to the floorboard with the washers, nuts, and bolts.
Connect the cable interface assembly to the EMA.
Make sure that the cables and hoses of the AAIR are clear of the height-adjustment crank, the
seat lock handle, and the seat-back adjustment lever.
Install the inertia reel (three-point air bag belt) in the airplane. Refer to Chapter 25, Flight
Compartment - Maintenance Practices.
Arm the AMSAFE inflatable restraints. Refer to AMSAFE Inflatable Restraint Disarm/Arm.
Remove the safety cable tie from the air bag buckle tongue.
Do a seat operation test on the pilot's and copilot's seat.
(a) Move the seat-back aft and forward to its maximum travel.
(b) Move the seat-base up an down to its maximum travel.
(c) Move the seat-base aft and forward to its maximum travel.
Do a functional test on the system. Refer to the AMSAFE Aviation AAIR Supplemental
Maintenance Manual, V23 System Diagnostic Tool - Operation and Maintenance Manual.

Inflatable Restraint System Adjustment/Test
A. The AAIR diagnostic check gives a system functional test of the AAIR circuits. To find problems in
system components, use a replace-and-test procedure. There are two seats in each AAIR system.
The 1 LED light will show an indication for the first seat on the AAIR system circuit. The 2 LED light will
show an indication for the second seat on the AAIR system circuit. Once the V23 system diagnostic
tool (SDT) is connected to the airplane, a check of the system is done one seat at a time.

© Cessna Aircraft Company

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MAINTENANCE MANUAL
B.

The V23 system diagnostic tool uses a 9-volt battery that can be replaced. A check of the diagnostic
tool must be done yearly. The label on the back of the diagnostic tool will show when a check of the
tool needs to be done. The diagnostic tool must only be sent to AMSAFE to be calibrated.

CAUTION: Calibrate the V23 system diagnostic tool again before use if it is hit,
shaken, or if it falls to the floor.
C.

Before the V23 system diagnostic tool is connected to the airplane, do the steps that follow.
(1) Set the SDT ON/OFF Switch to the ON position.
(2) Look at the Tool Battery Indicator LED light.
(a) If the LED light is green, the battery condition is satisfactory.
(b) If the LED light is red, replace the 9-volt battery on the back of the SDT.

D.

Do the System Functional Test.
NOTE:
(1)
(2)
(3)
(4)
(5)
(6)

There are two seats in each AAIR system. This functional test must be completed for each
AAIR system on the airplane.

Make sure that the seat belt safety buckles are not attached.
Remove the protective cap from the cable interface assembly.
Connect the V23 system diagnostic tool to the diagnostic connector.
Set the SDT ON/OFF Switch to the ON position.
Look at the Seat Position PASS/FAIL LED light.
If the 1 and 2 LED lights are amber, do the steps that follow. If the 1 and 2 LED lights do
not give an amber indication, troubleshoot the system. Refer to Inflatable Restraint System
Troubleshooting.
(a) Connect the air bag safety buckle on the seat.
(b) If the 1 LED light is green, the AAIR system for that seat is satisfactory.
(c) If there is an amber LED light indication, a red indication, or no indication, troubleshoot the
system. Refer to Inflatable Restraint System Troubleshooting.
(d) Disconnect the air bag safety buckle.
(e) Do the system functional test again for the second seat location.
NOTE:

For the second seat location, the 2 LED light will be used to give an indication.

(7) Set the SDT ON/OFF Switch to the OFF position.
(8) Disconnect the V23 system diagnostic tool from the diagnostic connector.
(9) Put the protective cap on the cable interface assembly.
8..

Inflatable Restraint System Troubleshooting
A. The procedures in this section must be done if the V23 system diagnostic tool gives an unsatisfactory
indication for the seats in the AAIR System Adjustment/Test. An unsatisfactory indication by the seat
LED light is an amber indication, red indication, or no indication. Ifthe V23 system diagnostic tool gives
a satisfactory indication after the replacement of the individual components, stop the troubleshooting
procedure.
(1) If an unsatisfactory indication is given before the safety buckle is connected, do the steps that
follow.
(a) Do a check of all connections and tighten loose connections that are found. Do the
Adjustment/Test procedure again if there are loose connections found.
(b) Replace the cable interface assembly. Do the Adjustment/Test procedure again.
(c) Replace the EMVA. Do the Adjustment/Test procedure again.
(d) Replace the inflator. Do the Adjustment/Test procedure again.
(2) If an unsatisfactory indication is given after the safety buckle is connected, do the steps that
follow.
(a) Replace the cable interface assembly. Do the Adjustment/Test procedure again.
(b) Replace the air bag safety buckle. Do the Adjustment/rest procedure again.
(c) Replace the EMA. Do the Adjustment/Test procedure again.
(d) Replace the inflator. Do the Adjustment/rest procedure again.

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MAINTENANCE MANUAL
PASSENGER COMPARTMENT - MAINTENANCE PRACTICES
1.

General
A.

This section gives instruction for the removal and installation of the aft seat and the seat belt and
shoulder harness assembly. The seat belt and shoulder harness components are non-repairable field
items. If any component does not operate correctly, the system must be replaced.

WARNING: If the airplane has AMSAFE inflatable restraints, do not do
maintenance on the seats, seat rails, seat belts, or shoulder
harnesses until you first look at and obey all applicable precautions
and instructions supplied in AMSAFE publications and this
maintenance manual. If you do not obey these instructions and
safety precautions, damage to equipment and harm to personnel
can occur.
B.

2.

If your airplane is equipped with the AMSAFE inflatable restraint system, do not do maintenance on
the seats or the seat restraint system unless you first obey all applicable precautions and instructions
in the E508804 Supplemental Amsafe Maintenance Manual and this Maintenance Manual. Refer to
Inflatable Restraint System - Maintenance Practices.

Aft Seat Removal/Installation
A.

Aft Seat Removal (Refer to Figure 201).

WARNING: If the airplane is equipped with AMSAFE inflatable restraints, do not
remove seats with the seat belts buckled or the EMA connected.
Damage can occur to the system and an accidental deployment of
the system can cause injury.
(1)
(2)

I

Remove the bolts and washers that attach the seat frame to the fuselage.
Remove the seat from the airplane.

B. Aft Seat Installation (Refer to Figure 201).
(1) Install the seat to the fuselage with the bolts and washers.
3.

|

4.

Seat Belt and/or Shoulder Harness Assembly Removal/Installation
A.

Seat Belt and Shoulder Harness Assembly Removal (Refer to Figure 201).
(1) If installed, remove the access covers to get access to the assembly hardware.
(2) Remove the nuts, bolts, washers, and spacers that attach the assemblies to fuselage and/or
seats.
(3) Remove the assembly from the airplane.

B.

Seat
(1)
(2)
(3)
(4)

Belt and Shoulder Harness Assembly Installation (Refer to Figure 201).
Install the assembly to the fuselage and/or the seat.
Make sure the spacers (if installed) are positioned correctly.
Install the access covers (if equipped).
Complete a check of the assembly for the correct installation and operation.

Seat Belt and Shoulder Harness Assembly Test
A.

The seat belt and shoulder harness assembly must have an inspection completed in accordance with
the time intervals in Chapter 5, Inspection Time Limits. Make sure you complete a check of the time
life of the assembly referred in Chapter 5, Component Time Life for these limits.

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MODEL 172
MAINTENANCE MANUAL

,

. A

SEA

ING

E
E

DETAIL

DETAIL

SEAT BACK
ADJUSTMENT
HANDLE

NUT

B(

DETAIL

B

SPACE
FLAT
WASHER
BOLT

DETAIL

BOLT

D

:Q
VVl-^lI 1c1 I

DETAIL C

0510T1007
A0519T1034
B0519T1035
C0519T1049
D0519T1049
E1219T1003

Aft Seat Installation
Figure 201 (Sheet 1)

25-20-00
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
INTERIOR UPHOLSTERY - MAINTENANCE PRACTICES
1.

General

A.
2.

Cabin Panels Removal/Installation
A.

I

3.

This section provides general instructions for removal and installation of the interior panels, carpet
and rubber mat.

Interior panels are typically attached to fuselage structure using screws. Refer to Figure 201 for an
exploded view of the interior panels, headliner and overhead console.

Door Panels, Carpet and Rubber Mat Removal/Installation
A.

Cabin door panels are typically attached to the fuselage and door structure using small screws. Carpet
and rubber mats are attached to the floorboard using Velcro. Refer to Figure 202 for a view of the
side panels, carpet and rubber mat.

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Apr 7/2003

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MODEL 172

MAINTENANCE MANUAL

BAGGAGE COMPARTMENT CLOSEOUT
UPPER BAGGAG
COMPARTMENT

SIDE PAN

DET
ILi"A rnl IkI-~lr-

I

f
SIDE WINDOW
TRIM

WINDLACE

GLARESHIELD
'UPPER FIREWALL UPHOLSTERY

DETAIL

B
7s

LOWER FIREWALL UPHOLSTERY
Cabin Interior Trim And Overhead Console Installation
Figure 201 (Sheet 1)

25-22-00
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
B1705

0

r=3'~~~~*

ELECTRICAL CONNECTOR

DETAIL C

C0519T1050

Cabin Interior Trim And Overhead Console Installation
Figure 201 (Sheet 2)

25-22-00
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B3271

DOORPOST MOLDING
/

J

GRILL CO\

DOORPOST

1O
DETAIL

D

LEFT SIDE SHOWN
RIGHT SIDE OPPOSITE
172080984 THRU 172081074 AND
172S087704 THRU 172S08908
D0719T1012

Cabin Interior Trim And Overhead Console Installation
Figure 201 (Sheet 3)

25-22-00
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Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1706

REAR PANEL

FORWARD SIDE PANEL

DOOR PANEL

/

/
0o

<:LL/i

.
'~~~~~~~~~~~~~~~~~~~~~~\
VIEW A-A
ACCENT TRIM
FORWARD SIDE PANEL

DOOR PANEL

REAR PANEL

o*

o

o

.y
I

ACCENT
TRIM

VIEW B-B
0510T1007
AA0519T1042
BB0519T1042

ACCENT TRIM

Cabin Side Panel And Floorboard Upholstery Installation
Figure 202 (Sheet 1)

25-22-00
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MODEL 172
MAINTENANCE MANUAL

B1707

AFT CARPET

R

FF PLATE

DETAIL A

A0519T1040

Cabin Side Panel And Floorboard Upholstery Installation
Figure 202 (Sheet 2)

25-22-00
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
CARGO TIE-DOWNS - MAINTENANCE PRACTICES
1.

General

A.

Cargo tie-downs are provided for the airplane to accommodate a variety of loading positions. These
tie-downs are secured directly to the floorboard through nutplates or indirectly to the floorboard through
seat rails. Refer to Figure 201 for an illustration of these tie- downs.

25-50-00
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Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
B1708

CARGO
RING
-- TIE-DOWN
- --

CARGO TIE-DOWN
LUG SLIDE ASSEMBLY

^

SEAT RAIL

0514T1010

Cargo Tie-Downs Installation
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
POINTER EMERGENCY LOCATOR TRANSMITTER

-

MAINTENANCE PRACTICES

1.General
A. This section gives maintenance practices for the Emergency Locator Transmitter (ELT). The ELT is
activated by an internal G-switch or manually by a remote switch on the instrument panel, or by the
ELT master switch. The ELT transmits an emergency distress signal on 121.5/243.0 MHz.
*2.

Pointer ELT Removal/installation

I
A.

ELT Removal (Refer to Figure 201).
(1) Get access to the ELT through the baggage compartment door on the left side.
(a) On airplanes without the G1000 system, remove the bolts, tiedowns, and plastic closeout
from the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and

~

(2)

~~~~Operation.

(b) On airplanes with the G1000 system, remove the molding between the upper baggage
comnpartment panel and the rear window trim.
Put the ELT master switch in the OFF/RESET (center)
position.

CAUTION: Do not disconnect the ELT remote connector before you put the ELT
master switch in the OFF/RESET (center) position. ELT internal
fuse failure can occur if the ELT remote connector is disconnected
before the ELT master switch is put in the OFF/RESET (center)
position.

B.

(3) Disconnect the ELT antenna coaxial cable from the ELT.
(4) Disconnect the ELT remote connector from the ELT.
(5) Disengage the attach strap from around the ELT and remove the ELT from the airplane.
ELT Installation (Refer to Figure 201).
(1) Complete an ELT G-Switch Operation Check. Refer to ELT Operational Test, ELT G-Switch
Operation Check.

CAUTION: Make sure that the direction-of-flight arrow on the ELT points to the
nose of the airplane.
CAUTION: Make sure that the ELT master switch is inthe OFF/RESET position.
ELT internal fuse failure can occur if the ELT remote connector is
installed with the ELT master switch in the ON or AUTO position.
(2) Put the ELT into the ELT bracket and tighten the ELT attach strap.
(3) Connect the ELT remote connector to the ELT.
(4) Connect the ELT antenna coaxial cable to the ELT.
(5) Put the ELT master switch in the AUTO position.
(6) Complete the Control Tower Monitored or Locally Monitored ELT Operational Test. Refer to
ELT Operational Test, Control Tower Monitored ELT Operational Test or Locally Monitored ELT
Operational Test.
(7) Install~the removed interior pieces.
(a) On airplanes without the Gi1 000 system, install the bolts, tiedowns, and plastic closeout to
the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and Operation.
(b) On airplanes with the G1000 system, install the molding between the upper baggage
compartment panel and the rear window trim.

©Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

INTERNAL
LOCKING

SKIN,

ANTENNA
DOUBLER

BRACKET
ASSEMBLY

SUPPORT

NEOPRENE
WASHER

MOUNTING
BRACKET
ATTACH STRAP
BASE PLATE

ITRANSMITTER
MASTER SWITCH

DETAIL

A

(WITH G-1000 SYSTEM)

REMOTE CONNECTOR
(TO REMOTE
MOUNTED SWITCH)
051 OTi007
A0518BT1
153

Pointer Emergency Locator Transmitter Installation
Figure 201 (Sheet 1)

25-60-00
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B220

DOUBLER

ANTENNA
ANCHOR

MASTER SWITCH
REMOTE CONNECTOR
(TO REMOTE MOUNTED SWITCH)
TRANSMITTER

BATTERY PACK
NEOPRI

MOUN]

DETAIL

A

(WITHOUT G-1 000 SYSTEM)
Pointer Emergency Locator Transmitter Installation
Figure 201 (Sheet 2)
©Cessna Aircraft Company

014
A0518BT1

25-6000

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B6406

DETAIL

B

REMOTE
SWITCH

DETAIL

C
B051 BT1109
C051 BT1109

Pointer Emergency Locator Transmitter Installation
Figure 201 (Sheet 3)

25-60-00
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MODEL 172

MAINTENANCE MANUAL

I

DETAIL

B

TCH

DETAIL

C

B0585T1 040
C0585T1 040

Pointer Emergency Locator Transmifter Installation
Figure 201 (Sheet 4)
©Cessna Aircraft Company

25-60-00

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL

3.

ELT Remote Switch Removal/installation

CAUTION: Do not disconnect the ELT remote connector before you put the ELT
master switch in the OFF/RESET (center) position. ELT internal fuse
failure can occur if the ELT remote connector is disconnected before the
ELT master switch is put in the OFF/RESET (center) position.
CAUTION: Disconnect the ELT remote connector from the ELT before you remove
the ELT remote switch or disconnect the ELT remote switch connector.
ELT internal fuse failure can occur if the ELT remote switch or disconnect
is removed before the ELT remote connector is disconnected.
A.

I
B.

ELT Remote Switch Removal (Refer to Figure 201).
(1) Put the aircraft master switch (ALT/BAT) to the OFF position.
(2) Get access to the ELT through the baggage compartment door on the left side.
(a) On airplanes without the GlOQO0 system, remove the bolts, tiedowns, and plastic closeout
from the lower baggage area (Zone 240). Refer to Airplane Zoning

~
(3)
(4)
(5)
(6)
(7)
ELT
(1)
(2)
(3)
(4)

-

Description and

~~~~Operation.

(b) On airplanes with the G1000 system, remove the molding between the upper baggage
compartment panel and the rear window trim.
Put the ELT master switch in OFF/RESET (center) position.
Disconnect the ELT remote connector from the ELT.
Get access to the back of the ELT remote switch (Zone 221).
Disconnect the ELT remote switch connector.
Compress and hold the locking tabs on the ELT remote switch. Pull the ELT remote switch aft
and away from the instrument panel.
Remote Switch Installation (Refer to Figure 201).0
Hold the edges of the ELT remote switch and put it into the instrument panel cutout.
Make sure the locking tabs engage and that the switch is correctly installed.
Connect the ELT remote switch connector.
Put the ELT remote switch to the AUTO position.

CAUTION: Make sure that the ELT master switch is inthe OFF/RESET position.

ELT internal fuse failure can occur if the ELT remote connector is
installed with the ELT master switch in the ON or AUTO position.
(5) Connect the ELT remote connector to the ELT.
(6) Put the ELT master switch in the AUTO position.
(7) Complete the Control Tower Monitored or Locally Monitored ELT Operational Test. Refer to
ELT Operational Test, Control Tower Monitored ELT Operational Test or Locally Monitored ELT
Operational Test.
(8) Install the removed interior pieces.
(a) On airplanes without the G1000 system, install the bolts, tiedlowns, and plastic closeout to
the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and Operation.
(b) On airplanes with the G1000 system, install the molding between the upper baggage
compartment panel and the rear window trim.
4.

ELT Antenna Removal/installation (integral Base with Coaxial Ca~ble)
A.

ELT Antenna Removal (Refer to Figure 201).
(1) Get access to the ELT and ELT antenna through the baggage compartment door on the left side.
(a) On airplanes without the G 1000 system, remove the bolts, tiedowns, and plastic closeout
from the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and

25-60-00
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C.--na Aircraft ComoanvI

-

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MAINTENANCE MANUAL
(b) On airplanes with the G1000 system, remove the molding between the upper baggage
compartment panel and the rear window trim.
(2) Disconnect the ELT antenna coaxial cable from the ELT.
(3) Remove all of the tie straps that attach the ELT antenna coaxial cable to the fuselage.
(4) On the external skin of the airplane, remove the six internal locking screws that attach the ELT
antenna to the fuselage.
NOTE:
(5)
B.

ELT
(1)
(2)
(3)
(4)
(5)
(6)

..91

5.

The ELT antenna has an integral base and coaxial cable.

Remove the ELT antenna from inside of the airplane.
Antenna Installation (Refer to Figure 201).
From inside the airplane, put the ELT antenna in position on the fuselage with the ELT antenna
pointing aft.
On the external skin of the airplane, use the internal locking screws to attach the ELT antenna
base to the fuselage.
Connect the ELT antenna coaxial cable to the ELT.
Use tie straps to attach the ELT antenna coaxial cable to the fuselage.
Complete the Control Tower Monitored or Locally Monitored ELT Operational Test. Refer to
ELT Operational Test - Control Tower Monitored ELT Operational Test or Locally Monitored ELT
Operational Test.
Install the removed interior pieces.
(a) On airplanes without the G 1000 system, install the bolts, tiedowns, and plastic closeout to
the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and Operation.
(b) On airplanes with the G1000 system, install the molding between the upper baggage
compartment panel and the rear window trim.

ELT Whip Antenna Removal/Installation.
A.

*

ELT

~~(1)
*
*
*

Whip

Antenna

Removal

(Refer

to

Figure

201).

Get access to the ELT and ELT antenna through the baggage compartment door on the left side.
~~~~(a)
On airplanes without the G 1000 system, remove the bolts, tiedowns, and plastic closeout
~~~~~from
the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and

~~~~~Operation.

()(b)

B.

Ank

W

6.

On airplanes with the G1000 system, remove the molding between the upper baggage
compartment panel and the rear window trim.
2)Disconnect the ELT whip antenna coaxial cable from the ELT whip antenna.
(3) From inside the airplane, remove the nut and washer that attach the ELT whip antenna to the
fuselage.
(4) Remove the ELT whip antenna from the external skin of the airplane.
ELT Whip Antenna Installation (Refer to Figure 201).
(1) Put the ELT whip antenna in position on the external skin of the fuselage with the ELT whip
antenna pointing aft.
(2) From inside the airplane, use the nut and washer to connect the ELT whip antenna to the
fuselage.
(3) Connect the ELT antenna coaxial cable to the ELT whip antenna.
(4) Complete the Control Tower Monitored or Locally Monitored ELT Operational Test. Refer to
ELT Operational Test, Control Tower Monitored ELT Operational Test or Locally Monitored ELT
Operational Test.
(5) Install the removed interior pieces.
(a) On airplanes without the G 1000 system, install the bolts, tiedowns, and plastic closeout to
the lower baggage area (Zone 240). Refer to Airplane Zoning - Description and Operation.
(b) On airplanes with the G1000 system, install the molding between the upper baggage
compartment panel and the rear window trim.

ELT Battery Pack Removal/installation.
A.

ELT Battery Pack Removal (Refer to Figure 201).

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WARNING: Obey the correct procedures to discard the unserviceable ELT
battery pack to prevent damage to the environment or personal
injury.
(1)
(2)
(3)
(4)
B.

Remove the ELT from the airplane. Refer to ELT Removal/installation.
Remove the screws that attach the ELT base plate to the ELT.
Disconnect the battery pack connector for the ELT.
Remove the ELT battery pack from the ELT.

ELT Battery Pack Installation (Refer to Figure 201).

CAUTION: Use only the recommended battery pack for the ELT, or the operating
life and/or signal strength of the ELT will decrease. The incorrect battery
pack can also change the mechanical configuration, which will cause too
much vibration and corrosion.
(1)
(2)

Put the ELT battery pack in the ELT.
Connect the ELT battery pack connector.

CAUTION: Do not tighten the ELT gasket and screws too much.
(3) Use screws to attach the ELT base plate and gasket to the ELT.
NOTE:

When the new battery pack expiration date is put in the airplane records, it is also
recommended that you record the expiration date in the ELT owner's manual for quick
reference.

Put the new replacement date on the outside of ELT transmitter with a stamp. Put the date on
the ELT switch nameplate, on the side of the ELT transmitter, and in instruction nameplate on
top of the ELT transmitter.
(5) Install the ELT in the airplane. Refer to ELT Removal/installation.
(4)

*7.

Pointer ELT Operational Test
A.

Control Tower Monitored ELT Operational Test.

CAUTION: Operate the Emergency Locator Transmitter (ELT) system only
during the first five minutes of each hour. Refer to the FAA Advisory
Circular AC-91 -44A.
(1) Request permission from the control tower and/or flight service station to do a test of the ELT
system.

CAUTION: Do not operate the ELT system for more than three pulses of the
audio signal. Longer operation can decrease the ELT battery power
supply.
NOTE:

The airplane's VHF receiver or ADF will not correctly do a check of the power of the
ELT audio signal.

(2) Put the ELT remote switch to the ON position.
(3) Contact the control tower and/or flight service station to make sure the ELT system operates
correctly.
(4) Momentarily put the ELT remote switch to RESET position.
(5) Put the ELT remote switch in the AUTO position.
(6) Contact the control tower and/or flight service station to make sure the ELT stopped transmission.

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B.

Locally Monitored ELT Operational Test.

CAUTION: Operate the Emergency Locator Transmitter (ELT) system only
during the first five minutes of each hour. Refer to the FAA Advisory
Circular AC-91-44A.
(1) (1) Put a small, hand held AM radio tuned to any frequency, within six inches of the ELT antenna.

CAUTION: Do not operate the ELT system for more than three pulses of the
audio signal. Longer operation can decrease the ELT battery power
supply.
NOTE:

The airplane's VHF receiver or ADF will not correctly do a check of the power of the
ELT audio signal.

(2) Put the ELT remote switch to the ON position.
(3) Make sure that the ELT signal is heard on the AM radio.
(4) Momentarily put the ELT remote switch to RESET position.
(5) Put the ELT remote switch in the AUTO position.
C.

ELT Master Switch Operational Test.

CAUTION: Operate the Emergency Locator Transmitter (ELT) system only
during the first five minutes of each hour. Refer to the FAA Advisory
Circular AC-91-44A.
CAUTION: Do not operate the ELT system for more than three pulses of the
audio signal. Longer operation can decrease the ELT battery power
supply.
(1)
(2)
(3)
(4)
D.

ELT
(1)
(2)
(3)
(4)
(5)
(6)

Put the ELT master switch to the ON position.
Make sure the signal is heard by either the Control Tower, Flight Service Station or AM radio.
Put the ELT master switch in the OFF/RESET position.
Put the ELT master switch in the AUTO position.
G-Switch Operational Check.
Remove the ELT from the airplane. Refer to ELT Removal/installation.
Put the ELT master switch in the AUTO position.
Hold the ELT tightly in one hand, and move the ELT fast in one direction, followed by a sudden
reversal of direction.
Make sure that the ELT G-switch has been actuated.
Put the ELT master switch in the OFF/RESET position to reset the ELT G-switch.
Install the ELT in the airplane. Refer to ELT Removal/installation.

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ARTEX C406-N EMERGENCY LOCATOR TRANSMI1TER

-

MAINTENANCE PRACTICES

1.General
A. This section gives maintenance practices for the emergency locator transmitter (ELT) system.
Components in the ELT system include the ELT, antenna, remote switch, and buzzer.
2.

Artex C406-N ELT Removal/installation.
A.

B.

ELT Removal (Refer to Figure 201).
(1) Get access to the ELT through the baggage compartment door on the left side.
(a) Remove the molding between the upper baggage compartment panel and the rear window
trim.
(2) Put the ELT master switch in the OFF position.
(3) Disconnect the electrical connector (PT905) and the coaxial connector (PT1 029) from the ELT.
(4) Loosen the knurl nuts on the end cap of the transmitter and the mounting tray.
(5) Pull the front cover away from the transmitter and the mounting tray.
(6) Carefully pull the mounting tray end and the tray away from the ELT.
(7) Remove the ELT from the mounting tray.
(8) Remove the screws that attach the mounting tray to the shelf assembly.
ELT Installation (Refer to Figure 201).
(1) Attach the mounting tray to the shelf assembly with the screws.

CAUTION: Make sure that the direction-of-flight arrow on the ELT points to the
nose of the airplane.
(2) Put the ELT transmitter in position in the tray at an angle. Move the locking ears at the end
opposite to the direction-of-flight arrow into the mounting tray locking slots.
(3) Make sure that the ELT switch on the ELT is in the OFF position.
(4) Put the mounting tray end in position on the ELT.
(5) Make sure that the slots at the end of the cover go into the locking ears on the ELT.
(6) Put the top cover on the top of the transmitter.
(7) Make sure that the top cover locks into the aft end of the transmitter.
(8) Put the end cap on the transmitter and the mounting tray.
(9) Tighten the knurl nuts.
(10) Connect the electrical connectors (PT905) and (PT1 029) to the ELT transmitter.
(11) Connect the electrical power to the airplane.
(12) Do a functional test of the ELT. Refer to Artex C406-N ELT Functional Test.
(13) Install the molding between the upper baggage compartment panel and the rear window trim.
3.

ELT Remote Switch Removal/installation
A. ELT Remote Switch Removal (Refer to Figure 201).
(1) Put the aircraft master switch (ALT/BAT) to the OFF position.
(2) Get access to the ELT through the baggage compartment door on the left side.
(a) Remove the molding between the upper baggage compartment panel and the rear window
trim.
(3) Put the ELT master switch in the OFF position.
(4) Disconnect the electrical connector (PT905) from the ELT.
(5) Get access to the back of the ELT remote switch (Zone 221).
(6) Disconnect the ELT remote switch connector.
(7) Remove the screws that attach the ELT remote switch to the instrument panel.
(8) Remove the ELT remote switch from the airplane.
B. ELT Remote Switch Installation (Refer to Figure 201).
(1) Put the ELT remote switch in position in the instrument panel.
(2) Attach the ELT remote switch to the instrument panel with the screws.
(3) Connect the ELT remote switch connector.
(4) Put the ELT remote switch to the AUTO position.

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SCREW

ANTENNA

SKI N
ELECTRICAL
CONNECTOR
(PT1 030)_

ASSEMBLY

BRACKET
ASSEMBLY

SUPPORT

0

MOUNTING
TRAY
SUPPORT
\JCY

SONA
BUZZI

TTER

COAX

NG
SWITCH
TRAY

I--L%
I 1I.jF

END CAP

CONNECTOR
(PT905)

DETAIL A

051OP1007
A0518T1 154

Artex C406-N ELT Installation
Figure 201 (Sheet 1)

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B6001

C

DETAIL

REMOTE
MOUNTED
SWITCH

B

Or' MEMAI

DETAIL

C
B0518T1 109
C0518T1 109

Artex 0406-N ELT Installation
Figure 201 (Sheet 2)
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(5) Connect the electrical connector (PT905) to the ELT.
(6) Make sure that the ELT master switch is set to the OFF position.
(7) Do a functional test of the ELT system. Refer to Refer to Artex 0406-N ELT Functional Test.
(8) Install the molding between the upper baggage compartment panel and the rear window trim.
4.

ELT Rod Antenna Removal/installation
A.

ELT Antenna Removal (Refer to Figure 201).
(1) Get access to the ELT and the ELT antenna through the baggage compartment door on the left
side.
(a) Remove the molding between the upper baggage compartment panel and the rear window
trim.
(2) Disconnect the coaxial cable connector (PT1 030) for the ELT antenna from the ELT.
(3) Remove the tie strap that attaches the ELT antenna coaxial cable to the fuselage.
(4) Remove the four screws that attach the ELT antenna to the fuselage.
(5) Remove the ELT antenna from the airplane.

B.

ELT Antenna Installation (Refer to Figure 201).
(1) Remove all of the old sealant from the ELT rod antenna and from the airplane skin. Refer to
Chapter 20, General Solvents/Cleaners - Maintenance Practices.
(2) Put the ELT antenna in position on the fuselage with the ELT antenna pointing aft.
(3) Install the four screws that attach the ELT antenna to the fuselage.
(4) Connect the ELT antenna coaxial cable to the ELT.
(5) With the tie strap, attach the ELT antenna coaxial cable to the mount on the fuselage.
(6) Make sure that there is a correct electrical bond between the antenna and the airplane structure.
(a) Remove one screw.
(b) With an ohmmeter, measure the electrical resistance from the antenna base metal insert
and back to the structure at the screw positon.
NOTE:

The maximum allowable resistance (in ohms) at each of the four measured
positions is 0.0025.

Install the screw and remove and install each of the remaining screws in turn as you
measure the electrical resistance at each screw hole.
(7) Apply a fillet seal around the antenna with Type I Class B Sealant. Do not cover the screw
head with the sealant. Refer to Chapter 20, Fuel, Weather and High-Temperature Sealing Maintenance Practices.
(8) Do a functional test of the ELT system. Refer to Refer to Artex 0406-N ELT Functional Test.
(9) Install the molding between the upper baggage compartment panel and the rear window trim.
(c)

5.

Buzzer Removal/installation
Buzzer Removal (Refer to Figure 201).
A.
(1) Get access to the buzzer through the baggage compartment door on the left side.
(a) Remove the molding between the upper baggage compartment panel and the rear window
trim.
(2) Make sure that the ELT master switch on the ELT transmitter is in the OFF position.
(3) Tag the wires and terminals for identification.
(4) Remove the screws that attach the electrical terminals to the buzzer.
(5) Loosen the black retainer ring on the outboard side of the buzzer.
(6) Remove the buzzer from the bracket.
B.

Buzzer Installation (Refer to Figure 201).
(1) Put the buzzer in the bracket.
(2) Install the black retainer ring on the outboard face of the buzzer.
(3) Connect the electrical wires to the buzzer with the screws.
(4) Do a check of the ELT system. Refer to Refer to Artex 0406-N ELT Functional Test.
(5) Install the molding between the upper baggage compartment panel and the rear window trim.

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ARTEX C406-N EMERGENCY LOCATOR TRANSMITTER

-

INSPECTION/CHECK

1.General
A. This section gives the procedures that are necessary to do the inspection and operational checks are
necessary to comply with 14 CFR 91 .207, for the Artex 0406-N Emergency Locator Transmitter (ELT)
System.
2.

Artex C406-N ELT Functional Test

CAUTION: Operate the Emergency Locator Transmitter system only during the first
five minutes of each hour. If you must complete the functional test at a
time other than the first five minutes of the hour, you must do the test
with a direct connection to the ELT and a 30 dB attenuator. Refer to the
FAA Advisory Circular AC-91-44A.
CAUTION: Do not operate the emergency locator transmitter for more than five
seconds at a time. Do not operate the ELT again for 15 seconds.
The ELT will transmit a 406.028 MHz signal after the ELT is active for
approximately 50 seconds. This signal is identified as a distress signal
A.

B.

C.

Prepare for the Artex C406-N ELT Functional Test.
(1) You must replace the ELT battery with a new ELT battery if one or more of the conditions that
follow occur:
*
Use of the ELT battery in an emergency
*
Operation for an unknown amount of time
*
Use for more than one hour of cumulative time
*
On or before the replacement date shown on the battery label.
(2) Examine the ELT battery to make sure that it is not due for replacement.
(3) If the battery must be replaced, follow the manufacturer's instructions to replace it.
(4) Supply +28 V, +0.25 or -0.25 V, external electrical power to the airplane.
(5) Initialize the global positioning system (GPS) on the multi function display (MFD).
Do the ELT Transmitter Test.
(1) Adjust the volume to make sure that the transmissions from the radio are heard in the cockpit.
(2) Adjust the COM 1 frequency to 121.50 MHz. Make sure that the audio is heard through the
cockpit speakers.
(3) Put the cockpit ELT switch in the ON position for approximately one second.
(4) Make sure that the ELT audio signal and the cockpit ELT switch light adjacent to the ELT remote
switch come on.
(5) Immediately put the cockpit ELT switch in the ARM position.
(6) Make sure that the LED stays on for approximately one second before it goes off.
(7) If the ELT system has sensed a fault in the system, the LED will flash a fault code at this time.
Refer to the Installation and Operation Manual for the Artex ELT system for information on the
possible codes.
Do the NAV Interface Test.
(1) Hold the SARSAT tester no more than fifteen feet from the antenna.
NOTE:

(2)
(3)
(4)
(5)
(6)

The SARSAT tester is used as an example to gather test information. However, other
equivalent test equipment such as the Aeroflex IFIR 4000 Communications Test Set
is acceptable.

Turn on the SARSAT tester.
Engage the receive function of the SARSAT tester.
Make sure that the display on the tester shows that it is searching for a signal.
Put the ELT remote switch in the ON position.
Within 15 seconds, put the ELT remote switch in the ARM position.

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(7) Monitor the SARSAT tester to see if it received a signal from the ELT system.
(a) If no signal was received, do the test again after the 15-second off cycle.
(8) Make sure that the tail number on the SARSAT tester is correct.
(9) Make sure that the Mode S code shown on the SARSAT tester is the same as the number that
is on the back of the transmitter.
(10) Make sure that the latitude and longitude information is the same as that shown on the MFD
display.
(11) Turn the SARSAT tester off.
(12) Disconnect external electrical power from the aircraft.
D.

Do the G-Switch Operational Test.

CAUTION: Operate the emergency locator transmitter (ELT) system only

during the first five minutes of each hour. If you must complete
the functional test at a time other than the first five minutes of the
hour, you must do the test with a direct connection to the ELT and
a 30-dB attenuator. Refer to the FAA Advisory Circular AC-91 -44A.
CAUTION: Do not operate the emergency locator transmitter (ELT) for more

than five seconds at a time. Do not operate the ELT again for 15
seconds. The ELT will transmit a 406.028 MHz signal after the ELT
is active for approximately 50 seconds. This signal is identified as
a distress signal.
(1) Remove the ELT from the airplane. Refer to Artex C406-N ELT Removal/Installation.
(2) Install a jumper wire between pins 12 and 13 on the electrical connector of the ELT.
NOTE:

The ELT will not activate with the G-switch unless electrical pins 12 and 13 have
a jumper wire installed between them (this happens automatically when the ELT is
locked into the mount tray with the electrical connector in position). Because of the
potential physical damage that can occur if the jumper wire is not installed correctly,
it is recommended that an experienced technician do this procedure.

(3) Put the ELT switch in the OFF position.
(4) Use a receiver, and set it to 121.5 MHz to listen for the aural warning sweep tone.
(5) Hold the ELT transmitter tightly in one hand and make a throwing movement followed by an
opposite movement of the ELT transmitter.
(6) Make sure that the G-switch operates and that the aural warning sweep tone is heard on the
receiver set to 121.5 MHz.
(7) Set the ELT switch to the ON position and then back to the OFF position to reset the G-switch.
(8) Remove the jumper wire from electrical pins 12 and 13 on the electrical connector of the ELT.
(9) Install the emergency locator transmitter in the airplane. Refer to Artex C406-N ELT Removal/
Installation.

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ARTEX ME406 EMERGENCY LOCATOR TRANSMITTER SYSTEM

-

DESCRIPTION AND OPERATION

1.General
A. An Artex ME406 Emergency Locator Transmitter (ELT) System is installed to help rescue teams find
the airplane in the event of a crash. It is made to operate in a wide range of environmental conditions
and is resistant to the forces caused by many types of accidents.
2.

Description
A.

B.

C.

3.

Artex ME406 ELT.
(1) The Artex ME406 Emergency Locator Transmitter (ELT) system includes an ELT unit, an integral
battery pack, warning buzzer, internal G-switch, antenna, remote switch, cable assembly, and
antenna coaxial cable. The ELT unit transmits on 121 .5 MHz and 406.028 MHz.
(2) The battery pack has two D-size lithium cells mounted under a battery cover. The battery pack
is replaced as necessary in the field.
(3) The ELT activates a buzzer that is installed near the ELT assembly. The buzzer makes a loud
noise to let people know that the ELT is on.
(4) The G-switch is internally installed in the ELT transmitter and is activated with a sudden reduction
in forward speed.
Artex ELT Antenna.
(1) The ELT system uses an antenna to transmit the emergency locator signal. The ELT antenna
is installed on top of the tailcone skin, forward of the vertical stabilizer. The ELT antenna is
connected with a coaxial cable to the ELT unit inside the dorsal.
ELT Remote Switch.
(1) The ELT remote switch is installed on the right panel. The ELT remote switch is a two-position
rocker switch that can be set in the ARM or the ON positions.

Operation

CAUTION: Operate the emergency locator transmitter (ELT) system only during the first
five minutes of each hour. If you must complete the functional test at a time
other than the first five minutes of the hour, you must do the test with a direct
connection to the ELT and a 30 dB attenuator. Refer to the FAA Advisory
Circular AC-91 -44A.
CAUTION: Do not operate the emergency locator transmitter (ELT) for more than five
seconds at a time. Do not operate the ELT again for 15 seconds. The ELT
will transmit a 406.028 MHz signal after the ELT is active for approximately
50 seconds. This signal is identified as a distress signal.
A.

B.

Artex ME406 ELT.
(1) During an accident, the ELT will activate automatically and transmit a standard swept tone on
121.5 MHz (emergency frequency). The 121.5 MHz signal will continue until the ELT battery has
expired. Every 50 seconds for 440 milliseconds, the 406.028 MHz transmitter will activate and
send a message to the satellite. The 406.028 MHz transmission will continue for 24 hours and
then stop. During operation, the ELT will receive electrical power from the ELT battery pack only.
ELT Remote Switch.
(1) The ELT can also be activated manually in the cockpit with the ELT remote switch. To manually
activate the ELT, put the ELT remote switch in the ON position. The red LED will come on when
the remote switch is set in the ON position. The ELT remote switch can also be used to do a
test of the ELT system (refer to Artex ME406 Emergency Locator Transmitter - Troubleshooting).
During typical operation, the ELT remote switch will be in the ARM position.

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ARTEX ME406 EMERGENCY LOCATOR TRANSMITTER SYSTEM

-

TROUBLESHOOTING

1.General
A. This section contains the information that is needed to complete the self test for the ARTEX ME406
Emergency Locator Transmitter (ELT) system. The system transmits on two frequencies at the same
time.
2.

3.

Tools and Equipment
A.
For information on tools and equipment, refer to Equipment and Furnishings

-

General.

ME406 Emergency Locator Transmitter Self Test Preparation

CAUTION: Operate the emergency locator transmitter (ELT) system only during the
first five minutes of each hour. If you must complete the functional test
at a time other than the first five minutes of the hour, you must do the
test with a direct connection to the ELT and a 30 dB attenuator. Refer to
the FAA Advisory Circular AC-91-44A.
CAUTION: Do not operate the emergency locator transmitter (ELT) for more than
five seconds at a time. Do not operate the ELT again for 15 seconds.
The ELT will transmit a 406.028 MHz signal after the ELT is active for
approximately 50 seconds. This signal is identified as a distress signal.
A.

B.

Prepare the Airplane for the ME406 Emergency Locator Transmitter Troubleshooting.
(1) Put the BATTERY switch in the ON position.
(2) Examine the ELT battery to make sure that it is serviceable.
(a) If the battery must be replaced, follow the manufacturers instructions to replace it.
ELT 121.5 MHz Test.
(1) Tune the receiver (usually the aircraft radio) to 121.5 MHz.
(2) Set the ELT instrument panel remote switch to the ON position and wait for 3 sweeps on the
receiver which takes about 1 second.
(3) Set the remote switch back to the ARM (OFF) position immediately and the switch LED and
buzzer will give 1 pulse. If more pulses are displayed, find the problem from the list below.
(a) One flash - Shows that the system is operational and that no error conditions were found.
(b) Three flashes - Shows an open or short condition on the antenna output or cable. Use the
list below to isolate and repair the problem:
1
Examine that the coaxial cable is connected and in good condition. Do a continuity
check of the center conductor and shield. Examine for a shorted cable.
2
Examine for a intermittent connection in the coaxial cable.
3 Examine the antenna installation if this error code persists. This can be examined
with a VSWR meter. Examine the antenna for opens, shorts, and a resistive ground
plane connection.
(c) Four flashes - This shows a low power condition. This occurs if the output power is below
approximately 33 dBrn (2 watts) for the 406.028 MHz signal, or 17 dBm (50mW) for the
121.5 MHz signal. Also this can show that the 406.028 MHz signal is off frequency. For
this error code the ELT must be sent back for repair or replacement.
(d) Five flashes - This shows that the ELT has not been programmed, however this does not
show erroneous or corrupted programmed data.
(e) Six flashes - This shows that the G-switch loop between pins 5 and 12 at the D-sub
connector is not installed. The ELT will not activate during a crash.
1
Do a resistance test to make sure the harness D-sub jumper is installed. There must
be less than 1 ohm of resistance between pins 5 and 12.
(f) Seven flashes - This shows that the ELT battery has too much accumulated operation time
and must be replaced to meet FAA specifications.

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I

C.

Put the BATTERY switch in the OFF position.

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-

MAINTENANCE PRACTICES

a

1.General
A. This section gives maintenance practices for the emergency locator transmitter (ELT) system.
Components in the ELT system include the ELT, antenna, remote switch, and buzzer.
2.

Emergency Locator Transmitter (ELT) Removal/installation
A. Remove the Emergency Locator Transmitter (ELT) (Refer to Figure 201).
(1) Make sure the MASTER switch is in the OFF position.
(2) Get access to the ELT through the baggage compartment door on the left side.
(a) Remove the closeout from the baggage area (Zone 240). Refer to Airplane Zoning
Description and Operation.
(3) Make sure the ONARM switch on the ELT in the ARM position.

-

CAUTION: Alth ough the ELT is off with the electrical connector removed, the
ELT can be activated if the switch on the front is moved to the ON
position. Be careful not to move the switch to the ON position.
(4) Disconnect the BNC connector (PT1 029) and the electrical connector (PT907) from the ELT.
NOTE:

B.

(5) Open the Velcro strap that holds the ELT to the mounting tray.
(6) Remove the ELT from the airplane.
Install the Emergency Locator Transmitter (ELT) (Refer to Figure 201).
NOTE:

0

The ELT is off when the electrical connector is removed from the ELT.

The ELT is off when the electrical connector is removed from the ELT.

CAUTION: Although the ELT is off with the electrical connector removed, the ELT
can be activated if the switch on the front is moved to the ON position.
Be careful not to move the switch to the ON position.
(1) Put the ELT in the mounting tray at an angle to engage the lock mechanism at the opposite end
of the ELT.
(2) Push the ELT down into the mounting tray until it is fully installed in the tray.
(3) Connect the Velcro strap that holds the ELT firmly to the mounting tray.
(4) Connect the BNC connector and the electrical connector to the ELT.
(5) Make sure the ONARM switch is in the ARM position.
(6) Complete a functional test of the ELT system to make sure the installation is correct. Refer to
Artex ME406 Emergency Locator Transmitter - Adjustment/Test.
(7) Install the closeout in the baggage area (Zone 240). Refer to Airplane Zoning - Description and
Operation.
3.

in

1W

ELT Buzzer Removal/installation
A. Remove the ELI Buzzer (Refer to Figure 201).
(1) Get access to the buzzer through the baggage compartment door on the left side.
(a) Remove the closeout from the baggage area (Zone 240). Refer to Airplane Zoning
Description and Operation.
(2) Make sure that the ELI master switch on the ELT transmitter is in the ARM position.
(3) Tag the wires and terminals for identification.
(4) Remove the screws that attach the electrical wire to the terminals to the buzzer.
(5) Loosen the black retainer ring on the outboard side of the buzzer.
(6) Remove the buzzer from the bracket.

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MAINTENANCE MANUAL

SCREW

SKIN
BNC
CONNECTOR
(PT1 030)_

ASSEMBLY

SUPPORT
BRACKET
MOUNTING

SUPPORT

WASHER
/
SCREW
BUZZE

::MERGENCY
-OCATOR
FRANSM ITTER

R

CONNECTOR
(PT1 029)

DETAIL A

051 0T1007
A0518T1 154

Artex ME406 Emergency Locator Transmitter System Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B6581

C

DETAIL

B

REMOTE

DETAIL

C
B0518T1 109
C0518T1 109

Artex ME406 Emergency Locator Transmitter System Installation
Figure 201 (Sheet 2)
Q Cessna Aircraft Company

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MODEL 172
MAINTENANCE MANUAL
B.

4.

5.

Install the ELT Buzzer (Refer to Figure 201).
(1) Put the buzzer in the bracket.
(2) Install the black retainer ring on the outboard face of the buzzer.
(3) Remove the tags from the wires and terminals.
(4) Connect the electrical wires to the buzzer with the screws.
(5) Do a check of the ELT system. Refer to Refer to Artex ME406 ELT Functional Test.
(6) Install the closeout in the baggage area (Zone 240). Refer to Airplane Zoning - Description and
Operation.

Remote Switch Removal/installation
A.

Remove the Remote Switch.
(1) Remove electrical power from the aircraft.
(2) Get access to the ELT through the baggage compartment door on the left side.
(a) Remove the closeout from the baggage area (Zone 240). Refer to Airplane ZoningDescription and Operation.
(3) Disconnect the electrical connector (PT907) from the ELT.
(4) Remove the screws from the front of the remote switch.
(5) Pull the remote switch from the panel to get to the electrical connector.
(a) Disconnect the connector from the back of the switch.

B.

Install the Remote Switch.
(1) Connect the electrical connector to the back of the switch.
(2) Put the remote switch into the panel.
(a) Install the screws that attach switch to the panel.
(3) Connect the electrical connector to the ELT.
(4) Complete a functional test of the ELT system to make sure the installation is correct. Refer to
Artex ME406 ELT Functional Test.
(5) Install the closeout in the baggage area (Zone 240). Refer to Airplane Zoning - Description and
Operation.

ELT Antenna Removal/installation
A.

B.

Remove the ELT Antenna (Refer to Figure 201).
(1) Remove the screws that attach the antenna to the fuselage.
(2) Pull the antenna upward from fuselage and disconnect the BNC connector (PT1030) from
antenna.
(3) Remove the antenna from the airplane.
(4) Remove sealant from antenna and airplane.
Install the ELT Antenna (Refer to Figure 201).
(1) Put the antenna near the mounting position and connect the BNC connector (PT1 030) to the
antenna.
(2) Install the screws that attach the antenna to the fuselage.
(3) Make sure that there is a correct electrical bond between the antenna and the airplane structure.
(a) Remove one screw.
(b) With an ohmmeter, measure the electrical resistance from the antenna base metal insert
to the structure at the screw position.
NOTE:

The maximum allowable resistance (in ohms) at each of the four measured
positions is 0.0025.

Install the screw and remove and install each of the remaining screws in turn as you
measure the electrical resistance at each screw hole.
(4) Apply a fillet seal around the antenna with Type I Class B Sealant. Do not cover the screw
head with the sealant. Refer to Chapter 20, Fuel, Weather and High-Temperature Sealing Maintenance Practices.
(5) Do a functional test of the ELT system. Refer to Artex ME406 ELT Functional Test.
(c)

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL
ARTEX ME406 EMERGENCY LOCATOR TRANSMITTER (ELT) SYSTEM

-

INSPECTION/CHECK

1.General
A. This section gives the procedures that are necessary to do the inspection and operational checks
necessary to comply with 14 CFR 91 .207, for the Artex ME406 Emergency Locator Transmitter (ELT)
System. The system transmits on two frequencies. The 121 .5 MHz frequency has the standard swept
tone that rescue personnel can follow to the source. The other frequency is 406.028 MHz and is used
to activate a satellite tracking system. The 406.028 MHz frequency includes other information such as
the country code of the airplane, the aircraft identification beacon serial number, the 24-bit address,
the tail number, or other identification.
2.

3.

Tools and Equipment
A. For information on tools and equipment, refer to Equipment and Furnishings

-

General.

Artex ME406 Emergency Locator Transmitter (ELT) Inspection
A. Get access to the ELT.
(1) Get access to the ELT through the baggage compartment door on the left side.
(a) Remove the bolts, tiedowns, and plastic closeout from the lower baggage area (Zone 240).
Refer to Airplane Zoning - Description and Operation.
B. Do an inspection of the ELT, mounting tray, antenna, and the ELT battery for condition and correct
installation.
(1) Make sure that the ELT switch, found on the forward end of the ELT, is set to the ARM position.
(2) Remove the ELT from the mounting tray. Refer to Artex ELT ME406 Emergency Locator
Transmitter System - Maintenance Practices.

CAUTION: Do not use solvents to clean the ELT, mounting tray, or electrical
contacts. Solvents used in these areas can cause damage to the
ELT housing.
(3) Examine the ELT and the mounting tray for correct installation, cleanliness, cracks, or other
damage.
(4) Examine the ELT battery for corrosion.
(5) Look at the battery expiration date.
(a) Make sure that the battery life limit is not expired.
(b) Make sure that the battery expiration date is shown correctly in the Maintenance Records.
NOTE:

The battery manufacturer puts a mark on the battery to show the battery life limit.
When you install a new battery in an ELT, make sure a record of the expiration
date is put in the space given on the ELT name and data plate.

(c) If you have to replace the ELT battery, refer to Artex Maintenance Manual 570-1600.
(d) You must replace the ELT battery with a new battery if one or more of the conditions that
follow occur:
* Use of the ELT battery in an emergency
* Operation for an unknown amount of time
* Use for more than one hour of cumulative time
* Replacement date shown on the battery label has expired.
(e) Record the new battery expiration date in the maintenance log if you replaced it.
(6) Examine the ELT antenna for correct installation and cracks or other damage.
(7) Install the ELT into the mounting tray. Refer to Artex ELT ME406 Emergency Locator Transmitter
System - Maintenance Practices.

© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

4.

Artex ME406 Emergency Locator Functional Test
NOTE:
A.

If possible, do the test procedure for the emergency locator transmitter inside a metal hangar
with the doors closed to decrease the signal transmission from the ELT unit during the test.

Do a G-Switch Operational Test:

CAUTION: Operate the Emergency Locator Transmitter (ELT) system only during

the first five minutes of each hour. If you must complete the functional
test at a time other than the first five minutes of the hour, you must do the
test with a direct connection to the ELT and a 30 dB attenuator. Refer to
the FAA Advisory Circular AC-91-44A.
CAUTION: Do not operate the Emergency Locator Transmitter (ELT) for more than

five seconds at a time. Do not operate the ELT again for 15 seconds.
The ELT will transmit a 406.028 MHz distress signal after it is activated
for approximately 50 seconds.

(1) Remove the ELT from the airplane. Refer to Artex ELT ME406 Emergency Locator Transmitter
System - Maintenance Practices.
(2) Install a jumper wire between pins 5 and 12 on the electrical connector of the ELT.

CAUTION: It is recommended that an experienced technician do this procedure
because of the potential physical damage that can occur if the
jumper wire is not installed correctly.
NOTE:

B.

The ELT will not activate with the G-switch unless electrical pins 5 and 12 have a
jumper wire installed between them (this happens automatically when the ELT is
locked into the mount tray with the electrical connector in position).

(3) Make sure the ELT switch is in the ARM position.
(4) Use a receiver set to 121 .5 MHz to listen for the aural warning sweep tone.
(5) Hold the ELT transmitter tightly in one hand and make a throwing movement followed by an
opposite movement of the ELT transmitter.
(6) Make sure that the G-switch operates and that the aural warning sweep tone is heard on the
receiver set to 121 .5 MHz.
the ELT switch to the ON position and then back to the ARM position to reset the G-switch.
Set
(7)
(8) Remove the jumper wire from electrical pins 5 and 12 on the electrical connector of the ELT.
(9) Install the emergency locator transmitter in the airplane. Refer to Artex ELT ME406 Emergency
Locator Transmitter System - Maintenance Practices.
Do a Transmitter Test of the Artex ME406 Emergency Locator Transmitter (ELT) System:

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MODEL 172
MAINTENANCE MANUAL

CAUTION: Operate the Emergency Locator Transmitter (ELT) system only
during the first five minutes of each hour. If you must complete the
functional test at a time other than the first five minutes of the hour,
you must do the test with a direct connection to the ELT and a 30
dB attenuator. Refer to the FAA Advisory Circular AC-91 -44A.
CAUTION: Do not operate the Emergency Locator Transmitter (ELT) for more
than five seconds at a time. Do not operate the ELT again for 15
seconds. The ELT will transmit a 406.028 MHz distress signal after
it is activated for approximately 50 seconds.
(1) Make sure the BATTERY switch and the AVIONICS switches are in the OFF position.
(2) Connect external electrical power to the airplane.
(3) Make sure that the COM/NAV 1 and AUD/MKR circuit breakers on the circuit breaker panel are
engaged.
(4) Set the BATTERY switch to the ON position.
(5) Set the AVIONICS switches to the ON position.
(6) Make sure that the ELT remote switch on the right panel is in the ARM position.
(7) Set one of the communication units to receive a frequency of 121.5 MHz.
(8) Set the communication unit to the airplane speakers at an audio level loud enough to be heard.
NOTE:

(9)

The SARSAT tester is used as an example to gather test information. However, other
equivalent test equipment such as the Aeroflex IFR 4000 Communications Test Set
is acceptable.

Have another person use the SARSAT tester set to the RECV function. Ref er to Figure 601.
NOTE:

The SARSAT tester must be less than 15 feet from the ELT antenna and must have
a line-of-sight between the ELT antenna and SARSAT tester.

NOTE:

The person with the SARSAT tester must make sure that the ELT buzzer is heard
during the test.

NOTE:

If it is necessary to do the transmitter test after the first five minutes of the hour, the
SARSAT tester is connected directly to the ELT with a coaxial cable and a 30 dB
attenuator. You will not hear the sweep tone from the ELT on the airplane speakers
with the attenuator installed.

(10) Install the 30 dB attenuator between the ELT and SARSAT tester if necessary.
(11) Set the ELT remote switch on the right panel to the ON position.
(12) Let the ELT make three sweeps on the airplane speakers.
NOTE:

This will take one second. The ELT remote switch will start to flash.

(13) Set the ELT remote switch back to the ARM position and monitor the LED.
NOTE:

The ELT will do a self-test. The LED will stay on for one second and the ELT sweeps
are not audible on the airplane speakers if the ELT operation is normal.

NOTE:

The ELT does not transmit a 406.028 MHz test signal to the SARSAT tester until the
ELT remote switch is set back to the ARM position.

(14) If the LED continues to flash, refer to Artex ME406 Emergency Locator Transmitter System Troubleshooting.
(15) If the SARSAT tester did not receivea 406.028 MHz signal and the ELT remote switch LED does
not show a transmitter problem, do the test again.

©DCessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(16) When the SARSAT tester receives a 406.028 MHz signal, scroll the pages on the tester and
make sure of the information that follows:
(a) Make sure the information shown by the SARSAT tester agrees with the placard on the
ELT.
NOTE:

(b)

The information that follows must match the data on the ELT placard:

* COUNTRY code
* 15-digit Hex code ID
* Aircraft identification number.
Make sure that the SARSAT tester shows the messages that follow:
* S TEST OK
* Frequency - PASS
* Homing frequency
* Message format (short).

NOTE:

When ownership of an aircraft is transferred within the same country, the ME406 ELT
should be reregistered with the applicable authority. When an aircraft with a ME406
ELT changes tail number or country registration, the ELT will need to have the new
identification data entered. The ELT will also need to be registered with the applicable
authority.

(17) Install the bolts, tiedowns, and plastic closeout to the lower baggage area (Zone 240). Refer to
Airplane Zoning - Description and Operation.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

L

ELT
BNC
CONNECTION
TO ANTENNA

DETAIL

A

NUME

F-

LIFT THE DOOR TO GET
ACCESS TO THE CONTRA ST
KNOB ADJUSTMENT

CLEAR

CAP

$.4

5

6--

F~F~1rn__rjFjFi

2137P

rM[-I C

mEI
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+

4
il

JDJJ l

COVER
0510T1007
A2618T1 109
66 18T1379

Artex ME406 Emergency Locator Transmitter (ELT) SARSAT Test Set-up
Figure 601 (Sheet 1)

Q Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

A64 137

COAXIAL CABLE
SARSAT TESTER

COAXIAL CABLE
TO ELT

ATTACHES TO ELT

380
6618ST1

Artex ME406 Emergency Locator Transmitter (ELT) SARSAT Test Set-up
Figure 601 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
CARBON MONOXIDE DETECTOR

-

MAINTENANCE PRACTICES

1.General
A. The carbon monoxide (GO) detector is installed on Airplanes 17281273 and On and Airplanes
172S1 01 03 and On that have the Garmin G1 000.
B. The CO detector detects, measures, and gives an alert to the crew before the cockpit level of CO
reaches a critical level. The CO data is displayed and controlled through the CO detector RS232
interface with the Multi-Function Display (MFD).

I
2.

Carbon Monoxide Detector Removal/installation
A. Carbon Monoxide Detector Removal (Refer to Figure 201).
(1) Put the AVIONICS MASTER switch in the off position.
(2) Remove the MFD from the pilot side of the instrument panel. Refer to Chapter 34, Control
Display Unit - Maintenance Practices.
(3) Disconnect the electrical connector (P1903) from the CO detector.
(4) Remove and keep the three screws and three washers that connect the CO detector to the
avionics support structure.
(5) Remove the CO detector from the airplane.
B. Carbon Monoxide Detector Installation (Refer to Figure 201).
(1) Put the CO detector in position on the avionics support structure.
(2) Attach the CO detector to the structure with the three kept screws and three kept washers.
(3) Connect the electrical connector (P1 903) to the CO detector.
(4) Install the MFD on the pilot side of the instrument panel. Refer to Chapter 34, Control Display
Unit - Maintenance Practices.
(5) Put the AVIONICS MASTER switch in the ON position.
(6) On the Primary Flight Display (PFD), do a check to make sure that the CO detector operates
correctly.

© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

AVIONICS
SUPPORT
STRUCTURE
(REFERENCE)

TRAY
ASSEMBLY
(REFERENCE)
CARBON
MONOXIDE
DETECTOR

DETAIL A
AIRPLANES THAT HAVE GARMIN G1 000

051lOTi 007
A0518T1 150

Carbon Monoxide Detector Installation
Figure 201 (Sheet 1)

25-60-10
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
SOUNDPROOFING AND INSULATION - MAINTENANCE PRACTICES
1.

General
A.

B.

The airplane utilizes soundproofing and insulation throughout the fuselage area. This material is glued
into place using spray adhesive. Anytime old material is being replaced, care should be taken to
ensure all traces are removed from fuselage skin before reapplication. For a list of spray adhesives,
refer to Equipment/Furnishing - General.
For an illustration of soundproofing and insulation locations, refer to Figure 201 and Figure 202.

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL

B1710

/

0519T1029

Soundproofing Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1711

0519T1030

Insulation Installation
Figure 202 (Sheet 1)

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CHAPTER

FIRE PROTECTION

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

26-00-00

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Apr 7/2003

26-20-00

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Apr 7/2003

26-Title
26-List of Effective Pages
26-Record of Temporary Revisions
26-Contents

26 - LIST OF EFFECTIVE PAGES
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RECORD OF TEMPORARY REVISIONS
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Number

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By

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MAINTENANCE MANUAL

CONTENTS
Scope and Definition ........................................................

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HAND FIRE EXTINGUISHER - DESCRIPTION AND OPERATION ...................
Description .................................................................
Operation ..................................................................

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FIRE PROTECTION - GENERAL..................................................

CONTENTS
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MAINTENANCE MANUAL
FIRE PROTECTION - GENERAL
1.

Scope and Definition
A.

This chapter contains a single section which describes the portable fire extinguisher used in the cabin.

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MAINTENANCE MANUAL
HAND FIRE EXTINGUISHER - DESCRIPTION AND OPERATION
1.

Description
A.

2.

A portable, hand operated fire extinguisher is mounted on the floor between the pilot and copilot
seats for use in the event of a fire. The extinguishing agent is Halon 1211 and may be used on
solid combustible, electrical or liquid fires. Servicing of the extinguisher can be handled by most
fire equipment dealers. The fire extinguisher is mounted within a quick release, clamp type bracket
assembly. (Refer to Figure 1).

Operation
A.

For operation of the fire extinguisher, refer to Section 7 of the Pilot's Operating Handbook.

26-20-00
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MAINTENANCE MANUAL

FIRE

B

_OT SEAT

DETAIL

A

BRACKET

DETAIL

B

0510T1007
A0514T1004
B0578T1001

Fire Extinguisher Installation
Figure 1 (Sheet 1)

26-20-00
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CHAPTER

FLIGHT CONTROLS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJ ECT

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DATE

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27
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Cessna Aircraft Company

-

LIST OF EFFECTIVE PAGES

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Number

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CONTENTS
FLIGHT CONTROLS - GENERAL .........................
G eneral. ...
... . . . . . . . . . . . . . . . . . . . . . . .
Tools, Equipment and Materials........................
Definition ..................................
CONTROL CABLE WIRE BREAKAGE AND CORROSION
MAINTENANCE PRACTICES ...........................
Examination of Control Cables ........................

. . . . . .

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AILERON CONTROL SYSTEM - TROUBLESHOOTING...............
Troubleshooting ...............................

27-10-00 Page 101
27-10-00 Page 101

AILERON CONTROL SYSTEM - MAINTENANCE PRACTICES............
General...................................
Control Yoke Removal/Installation.......................
Aileron Removal/installation..........................
Aileron Bell Crank Removal/installation ....................
Adjustment/Test ...............................
Cables And Pulleys Removal/installation....................
RUDDER CONTROL SYSTEM - TROUBLESHOOTING ...............
Troubleshooting ...............................
RUDDER CONTROL SYSTEM - MAINTENANCE PRACTICES............
General...................................
Rudder Pedal Assembly Removal/installation..................
Rudder Removal/installation .........................
Rudder Control Adjustment/Test........................

27-10-00
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ELEVATOR CONTROL SYSTEM - TROUBLESHOOTING ..............
Troubleshooting ...............................

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ELEVATOR CONTROL SYSTEM - MAINTENANCE PRACTICES...........
General...................................
Forward Elevator Bell Crank Removal/installation................
Aft Elevator Bell Crank Removal/Installation ..................
Elevator Removal/installation.........................
Elevator Control Adjustment/Test .......................
ELEVATOR TRIM CONTROL - TROUBLESHOOTING................
Troubleshooting ...............................
ELEVATOR TRIM CONTROL - MAINTENANCE PRACTICES.............
General...................................
Trim Tab Actuator Removal/installation.....................
Trim Tab Actuator Disassembly/Assembly ...................
Trim Tab Actuator Cleaning and Inspection...................
Trim Tab Free Play Inspection.........................
Trim Tab Control Wheel Removal/installation..................
Trim Tab Control Adjustment/Test .......................

27-30-00
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201
201
201
201
207
207
208
208

STALL WARNING SYSTEM - MAINTENANCE PRACTICES .............
General...................................
Scoop Assembly Removal/installation.....................
Stall Warning Horn Removal/Installation.....................

27-32-00
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27-32-00
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FLAP CONTROL SYSTEM - TROUBLESHOOTING.................
Troubleshooting ...............................

27-50-00 Page 101
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206
208

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL
FLAP CONTROL SYSTEM - MAINTENANCE PRACTICES..............
General...................................
Flap Motor and Transmission Assembly Removal/installation ..........
Flap Removal/Installation...........................
Flap Drive Pulley Removal/installation.....................
Flap Control System Adjustment/Test .....................
Operational Check..............................
FLAP FOLLOW UP AND INDICATING SYSTEM - MAINTENANCE PRACTICES.
Description and Operation ..........................
Follow Up and Indicating System Removal/Installation..............
System Rigging ...............................

27-50-00
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27 - CONTENTS
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
FLIGHT CONTROLS - GENERAL
1.

General
A.

2.

This chapter provides maintenance of components which furnish a means of manually controlling the
flight attitude characteristics of the airplane, including flaps.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes may be used for the following items:

NAME

NUMBER

Tensiometer

I

MANUFACTURER

USE

Available commercially

To measure and obtain
cable tension.

Inclinometer

SE716

Cessna
Aircraft
Company
Cessna
Distrubution
Department 701, CPD
25800 East Pawnee
Road
Wichita, KS
67218-5590

To measure control
surface deflection.

Polyurethane Tape

Y8761

3M
3M Center
Minneapolis, MN 55144

To prevent flap chafing.

3.

Definition
A.

This chapter is divided into sections and subsections to assist maintenance personnel in locating
specific systems and information. The following is a brief description of each section. For locating
information within the chapter, refer to the Table of Contents at the beginning of the chapter.
(1) The aileron section provides information on control wheels, cables, linkage and aileron
assemblies.
(2) The rudder section provides information on rudder pedals, cables, linkage and rudder assembly.
(3) The elevator section provides information on control column, cables, linkage and elevator
assemblies.
(4) The flap section provides information on the flap actuator, cables, linkage, and the flap
assemblies.

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MAINTENANCE MANUAL
CONTROL CABLE WIRE BREAKAGE AND CORROSION LIMITATIONS - MAINTENANCE PRACTICES
1.

Examination of Control Cables
A.

B.

C.

Control cable assemblies are subject to a variety of environmental conditions and forms of
deterioration. Some deterioration, such as wire or strand breakage, is easy to recognize. Other
deterioration, such as internal corrosion or cable distortion, is harder to identify. The following
information will aid in detecting these cable conditions.
Broken Wire Examination (Refer to Figure 201).
(1) Examine cables for broken wires by passing a cloth along length of cable. This will detect broken
wires, if cloth snags on cable. Critical areas for wire breakage are those sections of cable which
pass through fairleads, across rub blocks, and around pulleys. If no snags are found, then no
further inspection is required. If snags are found or broken wires are suspected, then a more
detailed inspection is necessary which requires that the cable be bent in a loop to confirm broken
wires. Loosen or remove cable to allow it to be bent in a loop as shown. While rotating cable,
inspect bent area for broken wires.
(2) Wire breakage criteria for cables in flap, aileron, rudder, and elevator systems are as follows:
(a) Individual broken wires at random locations are acceptable in primary and secondary
control cables when there are no more than six broken wires in any given ten-inch cable
length.
Corrosion.
(1) Carefully examine any cable for corrosion that has a broken wire in a section not in contact
with wear-producing airframe components, such as pulleys, fairleads, rub blocks, etc. It may be
necessary to remove and bend cable to properly inspect it for internal strand corrosion, as this
condition is usually not evident on outer surface of cable. Replace cable if internal corrosion is
found. If a cable has been wiped clean of its corrosion-preventive lubricant and metal-brightened,
the cable shall be examined closely for corrosion. For description of control cable corrosion, refer
to Chapter 51, Corrosion and Corrosion Control - Maintenance Practices

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MAINTENANCE MANUAL

B1713

BROKEN WIRE UNDETECTED BY
WIPING CLOTH ALONG CABLE

*'yzs

'y^

^^

,.--c^

ss-^

~

c-^

v-^

y ss^

BROKEN WIRE DETECTED VISUALLY
WHEN
AND BE

DO NOT BEND INTO LOOP SMALLER
THAN 50 CABLE DIAMETERS
NORMAL TECHNIQUE FOR
BENDING CABLE AND
CHECKING FOR BROKEN WIRES

5561T1 119

Cable Broken Wire Examination
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL
AILERON CONTROL SYSTEM - TROUBLESHOOTING
1.

Troubleshooting
A.

Actions listed in the Remedy column can be found in Aileron Control System - Maintenance Practices,
unless otherwise noted.

TROUBLE

PROBABLE CAUSE

REMEDY

LOST MOTION IN
CONTROL WHEELS

Loose control cables.

Adjust cables to proper tension.

Broken pulley or bracket, cable off
pulley or worn rod end bearings.

Replace worn or broken parts,
install cables correctly.

Sprung bellcrank.

Replace bellcrank.

Loose chains.

Adjust chain tension.

Cables too tight.

Adjust cables to proper tension.

Pulleys binding or cable off track.

Replace defective pulleys. Install
cables correctly.

Bellcrank distorted or damaged.

Replace bellcrank.

Defective U-joints.

Replace defective U-joints.

Clevis bolts in system too tight.

Loosen, then tighten properly and
safety.

Rusty chain or chain binding with
sprocket.

Replace chain or defective parts.

Improper adjustment of chains or
cables. With control wheel centered,
aileron bellcrank stop bushing should
be centered in slot (both left and right
bellcranks).

Adjust in accordance with Aileron
Control System - Maintenance
Practices (Adjustment/Test).

Improper adjustment of aileron
push-pull rods. If chains and cables
are properly rigged and bellcrank stop
bushings are not centered in slots,
push-pull rods are adjusted incorrectly.

Adjust in accordance with Aileron
Control System - Maintenance
Practices (Adjustment/Test).

DUAL CONTROL
WHEELS NOT
COORDINATED

Chains improperly adjusted.

Adjust in accordance with Aileron
Control System - Maintenance
Practices (Adjustment/Test).

INCORRECT
AILERON TRAVEL

Push-pull rods not adjusted properly.

Adjust in accordance with Aileron
Control System - Maintenance
Practices (Adjustment/Test).

Worn bellcrank stop bushings or
bellcrank slots.

Replace worn parts.

RESISTANCE TO
CONTROL WHEEL
MOVEMENT

CONTROL WHEELS
NOT LEVEL WITH
AILERONS NEUTRAL

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MAINTENANCE MANUAL
AILERON CONTROL SYSTEM - MAINTENANCE PRACTICES
1.

General
A.

2.

3.

The ailerons receive input from the pilot or copilot control wheel through a series of sprockets, chains,
pulleys, cables, bell cranks, and pushrods. For an overview of the system, refer to Figure 201. For a
breakdown of system components, refer to Figure 202, Figure 203, and Figure 204.

Control Yoke Removal/Installation
A.

Control Yoke Removal (Refer to Figure 202).
(1) Disconnect the battery cables and insulate the terminals as a precaution.
(2) Remove the center pedestal cover.
(3)
Remove the rudder bar shields, carpeting, and plates as necessary for access to the lower end
of the control yoke.
(4) Remove the avionics equipment and attaching hardware as necessary.
(5)
Remove the engine controls and the cabin air controls as necessary.
(6) Remove the right-forward side-upholstery panel.
(7) Remove the bolt from each end of the parking brake assembly and move the assembly away
from the work area.
(8) On the upper right side of the control yoke, remove the bolt that attaches the bearing to the
yoke. On the left side of the control yoke (Figure 202, Detail B), remove the equivalent bolt that
attaches the spacer and the roller to the upper yoke.
(9) Remove the instrument panel and the structure as necessary to let the yoke slide out under the
right side of the instrument panel.
(10) Remove the safety wire/clip and disconnect the direct cable turnbuckles.
(11) Remove the bolts that attach the control wheel tubes to the universal joints.
(12) Remove the bolt that attaches the elevator push-pull tube to the control yoke.
(13) Remove the pivot bolt from the bottom of the control yoke and carefully move the control yoke
out from under the right side of the instrument panel.

B.

Control Yoke Installation (Refer to Figure 202).
(1) Put the control yoke in position under the instrument panel.
(2) Attach the control yoke to the structure with the pivot bolt.
(3) Connect the elevator push-pull tube to the control yoke.
(4) Connect the control wheel tubes to the universal joints with the bolt.
(5) Connect the direct cable turnbuckles and safety the turnbuckles.
(6) Install the instrument panel structure and the instrument panel.
(7) Install the engine and the cabin-air control cables.
(8) Attach the spacers, rollers, bushings, and bearings on the upper left and the upper right control
yoke.
(9) Install the parking brake assembly to the structure.
(10) Do a rigging of the aileron cables. Refer to Adjustment/Test.
(11) Do a check and/or rigging of the elevator control system.
(12) Do a check and/or rigging of all of the engine and the cabin air controls.
(13) Do a check of all of the avionics and/or electrical equipment that possibly was disconnected or
stopped operation while you did the removal of the yoke.
(14) Install all items that you removed for access.

Aileron Removal/Installation
A.

Aileron Removal (Refer to Figure 203 and Figure 204).
(1) Remove the nut, washer(s), and bolt from the aileron pushrod, and disconnect the aileron
pushrod from the aileron.
(2) Disconnect the electrical bonding straps.
(3) Remove the screws and the nuts that attach the aileron hinges to the trailing edge of the wing.
(4) Carefully pull the aileron out and down to move the hinges from under the wing skin and the
auxiliary spar reinforcements.

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MAINTENANCE MANUAL

B

)

REFER TO FIGURE 204

D
IH

203

U

I AIL II

t

J

DETAIL C
DETAIL G

DETAIL J

DETAIL K

11007
T4001
T2001
IT.n-,
-UJol I lUU

DETAIL D
UtIAIL r

DETAIL

E

D0561T1012
E0561T1011
F0561T1006
G0561T1010
H0561T1009
J0561T1008
K0561T1012

Aileron Control System
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B2

A

CONTROL
WHEEL

BUSHING
BEARING

ROL
L

WASHER
-UNIVERSAL
JOINT
'SPROCKET

BOLT
UNIVERSAL JOINT
-CHAIN
-SECONDARY CABLE
TURNBUCKLE
- SECONDARY CABLE

PRIMARY CABLE

BUL I

DETAIL B

0510T1007
A0560T1001
B0560T1001

DETAILA
Control Yoke Installation
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL

.

. A

NOTE:

ADD WASHERS AS
NECESSARY TO
FILL THE GAP.

BUSHING
CARRY-THRU
CABLE TURNBUCKLE

SPAC
I
CARRY-THRU
CABLE

AILERON
PUSHROD

DIRECT CABLE

BRASS WASHER

LEFT AILERON
BELL CRANK

BOTTOM
WING SKIN
WASHERS

DETAIL A
LEFT SIDE SHOWN,
RIGHT SIDE TYPICAL

0510T1007
A05613001
A05613002

Aileron Bell Crank Installation
Figure 203 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B223

A

HINGE PIN

\

:,

o

o

o

DETAIL A
AILERON HINGE

0561T1014
A0561T1015

Aileron Installation
Figure 204 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
B.

4.

Aileron Installation (Refer to Figure 203 and Figure 204).
(1) Put the aileron hinges in position between the skin and the auxiliary spar reinforcements, and
install the screws and the nuts that attach the hinges to the trailing edge of the wing.
(2) Make sure that the hinge pins are attached with the screws and the nuts.
(3) Connect the electrical bonding straps.
(4) Attach the aileron pushrod to the aileron with the bolt, washer(s), and nut.
(a) Add washers as necessary to fill the gap.
(5) Do a check of aileron travel. Refer to Adjustment/Test below.

Aileron Bell Crank Removal/Installation
NOTE:

5.

The left and right aileron bell crank removal/installation is typical.

A.

Aileron Bell Crank Removal (Refer to Figure 203).
(1) Remove the access plate inboard of the bell crank on the underside of each wing.
(2) Loosen the carry-thru cable turnbuckle to release the control cable tension.
(3) Disconnect the control cables from the bell crank.
(4) Disconnect the aileron pushrod at the bell crank.
(5) Remove the nuts, washers, and bolts that attach the stop bushing of the bell crank and the bell
crank to the wing structure.
(6) Remove the bell crank through the access opening. Make sure that the bearing bushing is not
dropped from the bell crank.

B.

Aileron Bell Crank Installation (Refer to Figure 203).
(1) Install the bell crank to the structure. Make sure that the bushings are in the correct position.
(2) To take out excess clearance, install the brass washers between the lower end of the bell crank
and the wing channel.
(3) Connect the aileron pushrod to the bell crank.
(4) Connect the control cables to the bell crank. Make sure that the necessary spacers and bushings
are correctly installed.
(5) Adjust the cable tension. Refer to Adjustment/Test.
(6) Safety the turnbuckle. Refer to Chapter 20, Safetying - Maintenance Practices.

Adjustment/Test
A.

Rig Aileron Cables (Refer to Figure 205).
(1) Make sure that the primary cable is in the aft groove of the cable drum and that it is wound once
around the drum.
NOTE:

The primary cable lock is installed at the bottom of the drum and the direct cable lock
is installed at the top.

(2) With the control wheels in neutral, make sure that the chain ends are approximately equal
distances from the center of the sprockets.
(3) With the control wheels in the neutral position, tighten the secondary cable turnbuckles so that
the control wheels are level in the neutral position (synchronized). There must be sufficient
tension on the cables, but they must also move freely. Results of turnbuckle adjustment are as
follows:
(a) When you loosen the secondary cable turnbuckles and tighten the direct cable turnbuckles
at the center of the control yoke, the inboard sides of both control wheels move down.
(b) When you tighten one or both of the primary control cable turnbuckles and loosen the
secondary cable turnbuckles at the center of the control yoke, the outboard side of the
applicable control wheel will move down.
(4) Put a bar in position and attach it with tape across the two control wheels to hold them in the
neutral position.
(5) Adjust the direct cable turnbuckles below the control yoke and the single carry-thru turnbuckle at
the aileron bell crank so that the bell crank stop bushings are centered in the two bell crank slots
with 40 pounds, +10 or -10 pounds (177.93 N, +44.48 or -44.48 N) of tension at 70 °F (21 °C) on

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MODEL 172

MAINTENANCE MANUAL

1

70

EIw
J

J1

60 _

TENSION 40 POUNDS AT 70 "F

-

s

I

Q

-

I

I

_

I

U1LPPER LIMIT
-...
-1 - -

I

2

UJ

- -

I

"

I1

NOMINAL

A4

20II

I

!

;

2L

_

-

I

l

-fI

,
~, =

=

10

°

J

I;

-

0

i

r

I

AILERON CABLES 40.125-INCH DIAMETER)

z

0
30
U03

I

I

=

T|WTfTtl
TTrTtjT
tiT'T[lTiTTTT
ii
ITlTIIiii
-40 -30 -20 -10
0
10 20 30 40 50 60
DEGREES FAHRENHEIT

Tlil
iIliT l .l ITY'T
70
0B 80 90 100 1-O

300
TENSION 178 N AT 21 0C
Un

250

LU

I

E I

_

z
0

AILERON CABLES 3.18-mm DIAMETER)
200

z:

-i

UPPER IMI

1 sis
A* :iii,4i
I -

|

UPPER LIMIT

_ _

150

E =
]

1

NOMINAL

-1

--

[

1tO
MI

i

L,&~LO

.WER

L

IMIT

50
0

r

11

IIll

-40

fI

*35 -30

-25

-20

I

I

-15

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.I

T 11
Till

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rllll
ITill
11 r I
Th1A....1 1 I iiil""1
Ill 11111IIrtiiT
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.
.
I
5
10 15 20 25 30
35 40

DEGREES CELSIUS
Aileron Cable Tension
Figure 205 (Sheet 1)
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MODEL 172
MAINTENANCE MANUAL
the aileron carry-thru cable. Refer to Figure 205 for the correct tensions at other temperatures.
Ignore the tension on the direct cables. This tension will be different than the tension on the
carry-thru cable.
(6) Adjust the pushrods at the two ailerons until the ailerons are neutral with reference to the trailing
edge of the wing flaps. Be sure that the wing flaps are fully up when you make this adjustment.
(7) Remove the bar from the control wheels.
(8) With an inclinometer, do a check of the ailerons for correct travel. Make adjustments if necessary
and make sure that the bushing travel stops are correctly centered in the bell cranks.
NOTE:

For aileron rigging specifications, refer to Chapter 6, Airplane Dimensions and
Specifications - Description and Operation.

(9) Safety all turnbuckles. Refer to Chapter 20, Safetying - Maintenance Practices.
(10) Install all items that you removed for access.

WARNING: Make sure that the ailerons move in the correct direction when
you move the control wheel.
(11)
6.

Do a check for the correct travel of the aileron.

Cables And Pulleys Removal/Installation
A.

Cables and Pulleys Removal.
(1) Remove the access plates, wing root fairings, and upholstery as necessary.
(2) Disconnect the cables from the aileron bell cranks and remove the cable guards and the pulleys
as necessary to move the cables free of the aircraft.
NOTE:

B.

To ease the routing of cables, a length of wire can be attached to the end of the cable
before it is removed from the airplane. Leave the wire in position, installed through
me structure; ana men attacn tne caDle tnat you install ana use tne wire to pull me
cable into position.

Cables and Pulleys Installation.
(1) Route the cable and install the pulleys and the cable guards.
NOTE:

Make sure that the cable is in the correct position in the pulley groove before you
install the guard.

(2) Do a rigging of the aileron system.
(3) Safety the turnbuckles.
(4) Install the access plates, fairings, and upholstery.

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MAINTENANCE MANUAL
RUDDER CONTROL SYSTEM - TROUBLESHOOTING
1.

Troubleshooting
A.

Actions listed in the Remedy column can be found in Rudder Control System - Maintenance Practices,
unless otherwise noted.

TROUBLE

PROBABLE CAUSE

REMEDY

RUDDER DOES NOT
RESPOND TO PEDAL
MOVEMENT

Broken or disconnected cables.

Connect or replace cables.

BINDING OR JUMPY
MOVEMENT OF
RUDDER PEDALS

Cables too tight.

Ensure distance from firewall to
pivot shaft is 6.50 inches.

Cables not riding properly on pulleys.

Route cables correctly over
pulleys.

Binding, broken or defective pulleys or
cable guards.

Replace defective pulleys and
install guards properly.

Pedal bars need lubrication.

Lubricate as required.

Defective rudder bar bearings.

If lubrication fails to eliminate
binding, replace bearing blocks.

Defective rudder hinge bushings.

Replace defective bushings.

Clevis bolts too tight

Readjust to eliminate binding.

Steering rods not adjusted properly.

Re-rig system. Refer to Rudder
Control Adjustment/Test.

LOST MOTION
BETWEEN RUDDER
PEDALS AND
RUDDER

Insufficient cable tension.

Ensure distance from firewall to
pivot shaft is 6.50 inches.

INCORRECT
RUDDER TRAVEL

Incorrect rigging.

Re-rig system. Refer to Rudder
Control Adjustment/Test.

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MODEL 172
MAINTENANCE MANUAL
RUDDER CONTROL SYSTEM - MAINTENANCE PRACTICES
1.

General
A.

2.

Rudder control is maintained through use of conventional rudder pedals which also control nose wheel
steering. The system is comprised of rudder pedals, cables and pulleys, all of which link the pedals
to the rudder and nose wheel steering. For an illustration of the rudder system, refer to Figure 201.

Rudder Pedal Assembly Removal/Installation
A.

Remove Rudder Pedal Assembly (Refer to Figure 201).
(1) Remove upholstery from area below instrument panel as necessary.
(2) Disconnect master cylinders at pilot rudder pedals.
(3) Disconnect parking brake cables at master cylinders.
(4) Remove rudder pedals and brake links.
(5) Relieve cable tension at clevis adjustments.
(6) Disconnect cables, return springs, trim bungee and steering tubes from rudder bars.
(7) Remove bolts securing bearing blocks and work rudder bars out of area below instrument panel.

B.

Install Rudder Pedal Assembly (Refer to Figure 201).
NOTE:

(1)
(2)
(3)
(4)
(5)
(6)
(7)
3.

Rudder bar assemblies should be checked for excessive wear before installation. The
bearing blocks are nylon and require no lubrication unless binding occurs. A few drops of
general purpose oil should eliminate such binding.

Position rudder bars in area below instrument panel and secure bearing blocks with bolts.
Reconnect cables, return springs, trim bungee and steering tubes to rudder bars.
Set distance from pivot shaft to firewall at 6.50 inches.
Install rudder pedals and brake links.
Connect parking brake cables at master cylinders.
Connect master cylinders at pilot rudder pedals.
Install upholstery to tunnel area as necessary.

Rudder Removal/Installation
A.

Remove Rudder (Refer to Figure 201).
(1) Disconnect shackles at rudder bellcrank.
(2) Disconnect tail navigation light quick-disconnect at bottom of rudder.
(3) With rudder supported, remove hinge bolts (including electrical bonding strap) and lift rudder
free of vertical fin.

B.

Install Rudder (Refer to Figure 201).
(1) Install rudder (with electrical bonding strap) to vertical fin. Torque nuts to 50 to 70 inch pounds
plus free running torque.
(2) Reconnect tail navigation light quick-disconnect at bottom of rudder.
(3) Attach shackles to rudder bellcrank.
NOTE:

4.

Do not over tighten. Shackle must pivot freely.

Rudder Control Adjustment/Test
A.

Rig Rudder Controls.
NOTE:

For rudder travel angles, refer to Chapter 6, Airplane Dimensions and Specifications Description and Operation.

(1) Using a digital inclinometer, adjust travel stops on rudder to obtain proper rudder travel.

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MODEL 172
MAINTENANCE MANUAL

RIGHT
REAR

H

RIGHT
FRONT
CABLE

LEFT REAR
CABLE

J
LEFT FRONT
CABLE

DETAIL A
RIGHT FORWARD
RUDDER

6.50

C
AFT RUDDER BAR
BEARING BLOCK
RETURN SPRIN(
CLEARANCE HOLE ON
FORWARD RUDDER BAR
FORWARD RUDDER BAR

E

BRAKE TORQUE TUBE
MASTER '
CYLINDER

DETAIL C

DETAIL

B

BRACKET

B0562T2005
B0563T1002
C0562T1008

Rudder Control Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B224

.'

-l

.

,"

II

I. I -\

-LLY

- A D1

CABLE
GUARD

SPACER

I

DETAIL D
LE

DETAIL

J
BELLCRANK
PULLEY
rUIJLLL I
BRAKE TORQUE
TUBE

DETAIL E

DETAIL H

RUDDER
BAR

SHACI

^

RUDDER

'1_0

DETAIL

G

TRAVEL

DETAIL F

STOPS

D0562T3003
E0562T3003
F0562T2005
F0563T1002
G0562T2003
H0561T1007
J0563T1003
K0561T1013

Rudder Control Installation
Figure 201 (Sheet 2)

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(2) As an alternate means of establishing travel limits, refer to Figure 202 in conjunction with the
following steps:
(a) Establish neutral position of rudder by clamping straightedge (such as wooden 2 X 4) on
each side of fin and rudder, and blocking trailing edge of rudder half the distance between
straightedges as shown in Figure 202.
(b) Tape a length of soft wire to one elevator in such a manner that it can be bent to index with
a point on rudder trailing edge just above the lower rudder tip (disregard fixed trim tab).
(c) Using soft led pencil, mark rudder at point corresponding to soft wire indexing point
(neutral).
(d) Remove straightedges.
(e) Hold rudder against right, then left rudder stops. Measure the distance from pointer to
pencil mark on rudder in each direction of travel. Distance should be between 5.29 inch
and 5.91 inch.
(3) After rudder travel has been established, disconnect nose wheel steering tubes from nose strut.
(4) Establish rudder neutral position by clamping straight edge such as wooden 2x4 on each side
of vertical stabilizer and rudder and blocking trailing edge of rudder half the distance between
the straightedges.
(5) Adjust cables at clevis to align rudder and pedals in neutral position to 6.50 inches from firewall
to pedal pivot shafts. Cable tension is automatically set by return springs on the rudder bar.
NOTE:

Due to thickness of insulation of firewall, it is recommended that a piece of 0.0625
inch welding rod be ground to a sharp point and notched at the 6.50 inch dimension.
Pierce insulation on firewall and use notch to measure proper dimension.

(6) Tie down or weight tail to raise nose wheel free of ground.
(7) Center nose gear against external stop.
NOTE:

Do not compress springs when extending steering tubes.

(8) Extend steering tubes until free play is removed.
(9) Adjust steering tube rod ends to 1.00 inch between steering arm assembly and bolt hole and
tighten jam nuts.
(10) Adjust steering tube clevises to align with rod end bearings.
NOTE:

Extend steering tubes to seat rods against internal springs, but do not attempt to
preload these springs by shortening rod end clevises after alignment. Preload is built
into steering tubes.

(11) Install clevises on rod ends.
(12) Safety clevises, remove tail stand and straight edges and install all items removed for access.

WARNING: ENSURE THAT RUDDER MOVES IN CORRECT DIRECTION
WHEN OPERATED BY RUDDER PEDALS.
(13) Flight test airplane to determine if ground adjustment of fixed trim tab is necessary.
NOTE:

Do not rig rudder off-center unless trim tab does not provide adequate correction.

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MODEL 172
MAINTENANCE MANUAL

B226

STEP 1:

(2 X 4)

ESTABLISHING NEUTRAL
POSITION OF RUDDER.

STEP 2:

MEASURING
RUDDER TRAVEL.

VERTICAL

RUDDE

BLOCK
5.29 INCH TO-,,
5.91 INCH

BLOCK RUDDER HALF
THE DISTANCE BETWEEN
STRAIGHTEDGES

WIRE
POINTER

0562T1009
0562T1009

Rudder Travel Adjustment
Figure 202 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
ELEVATOR CONTROL SYSTEM - TROUBLESHOOTING
1.

Troubleshooting
NOTE:

Due to remedy procedures in the following troubleshooting chart, it may be necessary to rerig
system.

TROUBLE

PROBABLE CAUSE

REMEDY

NO RESPONSE TO
CONTROL WHEEL
FORE AND AFT
MOVEMENT

Forward or aft end of push- pull tube
disconnected.

Attach push-pull tube correctly.

Cables disconnected.

Attach cables and rig system.

Defective forward or rear bellcrank
pivot bearing.

Move to check for play or binding.
Replace bellcrank.

Cables slack.

Adjust to specified tension per
rigging procedure.

Cables not riding correctly on pulleys.

Open access plates and observe
pulleys. Route cables correctly
over pulleys.

Nylon bearing on instrument panel
binding.

Disconnect universal joint and
check for binding. Replace bearing
if binding is felt.

Defective control yoke pivot bearing.

Disconnect elevator push-pull tube
at lower end of control yoke and
check that control yoke moves
freely. Replace bearing if found
defective.

Defective elevator hinges.

Move elevators by hand checking
hinges. Replace defective hinges.

Clevis bolts too tight.

Readjust to eliminate bolt binding.

Lubrication needed.

Lubricate in accordance with
Chapter 12, Flight Controls Lubrication.

Defective pulleys or cable guards.

Replace defective parts and install
guards properly.

Stops are incorrectly set.

Check elevator travel with
inclinometer. Re-rig system if
required.

Cables tightened unevenly.

Re-rig system.

Interference at instrument panel.

Re-rig system.

BINDING OR JUMPY
MOTION FELT IN
MOVEMENT OF
ELEVATOR SYSTEM

ELEVATORS FAIL TO
ATTAIN PRESCRIBED
TRAVEL

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MODEL 172
MAINTENANCE MANUAL
ELEVATOR CONTROL SYSTEM - MAINTENANCE PRACTICES
1.

General
A.

2.

3.

The elevators are operated by power transmitted through forward and aft movement of the control
yoke. This movement goes to the elevators through a system that has a push-pull tube, cables, and
bell cranks. The elevator control cables, at their aft ends, are attached directly to a bell crank that is
installed between the elevators. This bell crank connects the elevators, and is a bearing point for the
travel stop bolts. A trim tab is installed on the right elevator. For an illustration of the elevator control
system, refer to Figure 201.

Forward Elevator Bell Crank Removal/Installation
A.

Forward Elevator Bell Crank Removal (Refer to Figure 201).
(1) Remove the front seats and the carpet. Refer to Chapter 25, Front Seats - Maintenance
Practices and Interior Upholstery - Maintenance Practices.
(2)
Remove the floorboard access panels. Refer to Chapter 6, Access/Inspection Plates Description and Operation.
(3) Release the cable tension at the turnbuckles and disconnect the cables from the forward bell
crank.
(4) Disconnect the push-pull tube from the forward bell crank.
(5) Remove the pivot bolt and remove the forward bell crank.

B.

Forward Elevator Bell Crank Installation (Refer to Figure 201).
(1) Put the forward bell crank in position and install the pivot bolt.
(2) Connect the push-pull tube to the forward bell crank.
(3) Install the cables to the forward bell crank and do a rigging of the system. Refer to Elevator
Control Adjustment/Test.
(4) Install the floorboard access panels. Refer to Chapter 6, Access/Inspection Plates - Description
and Operation.
(5) Install the seats and the carpet. Refer to Chapter 25, Front Seats - Maintenance Practices and
Interior Upholstery - Maintenance Practices.

Aft Elevator Bell Crank Removal/Installation
A.

Aft Elevator Bell Crank Removal (Refer to Figure 201).
(1) Remove the rudder. Refer to Rudder Control System - Maintenance Practices.
(2)
Release the cable tension at the turnbuckles and disconnect the cables from the rear bell crank.
(3)
Remove the bolts that attach the elevators to the bell crank.
(4)
Remove the bell crank pivot bolt and slide the bell crank out from between the tube assemblies.
NOTE:

B.

4.

If necessary, remove one of the stabilizer attach bolts for clearance when you remove
the bell crank pivot bolt.

Aft Elevator Bell Crank Installation (Refer to Figure 201).
(1) Put the bell crank in position and install the pivot bolt. Replace all components that it was
necessary to remove when you removed the aft bell crank.
(2) Install the bolts that attach the elevators to the bell crank.
(3) Connect the cables to the rear bell crank and do a rigging of the system. Refer to Elevator
Control Adjustment/Test.
(4)
Install the rudder. Refer to Rudder Control System - Maintenance Practices.

Elevator Removal/Installation
A.

Elevator Removal (Refer to Figure 202).
NOTE:
(1)

This procedure is written for the right elevator with the attached trim tab. The left elevator
removal/installation is almost the same, but without the trim tab.

Disconnect the push-pull channel from the elevator trim-tab horn.

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MODEL 172
MAINTENANCE MANUAL

bl

D.7 4A

E

UP
CABLE

F

a_

|

AW_

X

X

VJ/-'DLr

DETAIL

B

ABLE

UP CABLE

DOWr

BELL CRANK

DETAIL

G

DETAIL C
nFTAII
L

D

]KLE
0510T1007
A0563T3002
B0563T1015
C0563T1015
D0563T1015
E0563T1003
F0563T1015
G0563T1014

DETAIL C
DETAIL

F

CABLE
Elevator Control System
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

R171;
Y'

AFT
BELL CRANK
BE
;EMBLY

DETAIL A

CHANNEL

ELEVATOR TRIM TAB

DETAIL B

A
ELEVATOR

B
I

C
r»/\l

D

BALANCE WEIGHT

T

SCR

NGE
IACKET

HORIZC
STABILI

HINm

BRACKET

DETAIL C

DETAIL U ."..)

A05631009
B05631008
C05631007
D05631006

Elevator Installation
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL
(2) Remove the bolts that attach the tube assembly to the aft bell crank.
(3) With a support for the elevator installed, remove the bolts from the elevator hinge brackets and
remove the elevator half.
B.

5.

Elevator Installation (Refer to Figure 202).
(1) Attach the elevator to the horizontal stabilizer at the hinge points with the bolts.
(2) Attach the tube assembly of the elevator to the aft bell crank.
(3) Connect the push-pull channel (opening down) to the elevator trim-tab horn.

Elevator Control Adjustment/Test
A.

Do the rigging of the Elevator (Refer to Figure 202, Figure 203, and Figure 204).
(1) Lock the elevator control in the neutral position with a neutral rigging tool.
(2) Streamline the elevators to neutral with the horizontal stabilizer.
NOTE:

Neutral position is measured with the bottom of the elevator balance area flush with
the bottom of the stabilizer.

(3) While you hold the elevators in the neutral position, adjust the turnbuckles equally to 30 pounds,
+10 or -10 pounds (133.45 N, +44.48 or -44.48 N), of cable tension at 70 °F (21 °C). Refer to
Figure 204 for the correct tensions at other temperatures.
(4) Mount an inclinometer on the elevator and as you keep the elevator streamlined with the
stabilizer, set the inclinometer to 0 degrees.
(5) Remove the control-column neutral rigging tool and adjust the travel stop bolts to the range of
travel in Chapter 6, Airplane Dimensions and Specifications - Description and Operation.
(6) Make sure that the control yoke does not touch the instrument panel in the full UP position or
the firewall in the full DOWN position.

WARNING: Make sure that the elevators move in the correct direction
when operated by the controls.
(7) Safety the turnbuckles and the travel stop bolts.
(8) Do a check of the remaining elevator control system to make sure that it is correctly attached.
(9) Install all items that you removed for access.

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MODEL 172
MAINTENANCE MANUAL

B1716

NEUTRAL RIGGING TOOL

NT PANEL
CONTROL COLUMN

A

SUPF

0.62 INCH

0.46 INCH

U\-P

t

--

0.19-INCH
RADIUS
(TYPICAL)

1ju

PRESS FIT

1.95

INCH

-*

O0

0

0.35-INCH
RADIUS
(TYPICAL)

0.30 INCH

DETAIL

NOTE:

A

MAKE TOOL FROM 0.125-INCH STEEL PLATE AND
0.209-INCH DIAMETER DRILL ROD.
0560T1005
A0560T1004

Control Column Neutral Rigging Tool
Figure 203 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

n,

-

---

--

-

50VC

i 40'
'

-,

'

ELEVATOR CAB

^

TENSrIO

1''1 i

30 PC

30
1-

20

i

10-

0

300

IiI
ni11i
l i
-40 -30 -21o
0

0

t

:

zZ

*30

10

20 30 40
50
DEGREES FAHRENHEIT

70

80.

100 110

9

I

Iri I I I I I I
-4

250Z

0

ELEVATOR1 CA

(
-i--1
I
-_ TENSt
13
1 ENSION.133

Zo
p

-

0 W]
50 -

--------

50-IIII 1111 1 13 I
40 -35 -30 -25 -20 -15

.~~~~~

.

-10

-5

0

5

10

15

20

26

30

35

40

45

DEGREES CELSIUS -

Elevator Cable Tension
Figure 204 (Sheet 1)
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ELEVATOR TRIM CONTROL - TROUBLESHOOTING
1.

Troubleshooting
NOTE:

Due to remedy procedures in the following chart, it may be necessary to re-rig the system after
trouble has been corrected.

TROUBLE

PROBABLE CAUSE

REMEDY

TRIM CONTROL
WHEEL MOVES WITH
EXCESSIVE FORCE.

Cable tension too high.

Adjust tension from 15 to 20
foot-Lbs at average temperature
for the area.

Pulleys binding or rubbing.

Repair or replace as necessary.

Cables not in place on pulley.

Install cables correctly.

Trim tab hinge binding.

Disconnect actuator and move tab
to check resistance. Lubricate or
replace hinge as necessary.

Defective trim tab actuator.

Remove chain from actuator
sprocket and operate actuator
manually. Replace actuator if
defective.

Rusty chain.

Replace rusty chain.

Damaged sprocket.

Replace damaged sprocket

Bent sprocket shaft.

Observe motion of sprockets.
Replace bent sprocket shaft.

Cable tension too low.

Adjust tension from 15 to 20
foot-Lbs at average temperature
for the area.

Broken pulley.

Replace defective pulley.

Cables not in place on pulleys.

Install cables correctly.

Worn trim tab actuator.

Remove and replace worn
actuator.

Actuator attachment loose.

Tighten.

TRIM INDICATOR
FAILS TO INDICATE
CORRECT TRIM
POSITION.

Indicator incorrectly engaged on wheel
track.

Reset indicator.

INCORRECT TRIM
TAB TRAVEL.

Stop blocks loose or incorrectly
adjusted.

Adjust stop blocks on cables.

LOST MOTION
BETWEEN CONTROL
WHEEL AND TRIM
TAB.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ELEVATOR TRIM CONTROL - MAINTENANCE PRACTICES
1.

General
A.

2.

The elevator trim tab on the right elevator is controlled by a trim wheel in the pedestal. Movement to
operate the tab goes from the trim control wheel with chains, cables, and an actuator. A mechanical
pointer adjacent to the trim wheel shows the tab position. A nose up setting on the trim wheel gives
a tab down position. For an illustration of tab system components, refer to Figure 201.

Trim Tab Actuator Removal/nstallation
A.

Trim Tab Actuator Removal (Refer to Figure 201 and Figure 202).
(1) Remove the baggage compartment aft wall for access to the stop blocks for the elevator trim
control cable. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.

CAUTION: Put a support stand under the tail tiedown ring when you work in
the tail of the airplane or the tailcone can fall.
(2)
(3)
(4)
(5)
(6)
(7)
B.

Trim
(1)
(2)
(3)
(4)
(5)
(6)

3.

Remove the safety wire and release the cable tension at the turnbuckle.
At the elevator hinge gap, disconnect the push-pull channel from the actuator.
Remove the access plate 320AB. Refer to Chapter 6, Access/Inspection Plates - Description
and Operation.
Remove the chain guard.
Remove the chain from the actuator sprocket.
Remove the screws that attach the actuator clamps to the bracket, and carefully work the
actuator out through the access opening.
Tab Actuator Installation (Refer to Figure 201 and Figure 202).
Put the actuator in position and attach the actuator clamps to the bracket with the screws.
Install the chain to the actuator sprocket.
Install the chain guard.
Install the access plate 320AB. Refer to Chapter 6, Access/Inspection Plates - Description and
Operation.
At the elevator hinge gap, connect the push-pull channel to the actuator.
Do the rigging of the trim system. Refer to Trim Tab Control Adjustment/Test.

Trim Tab Actuator Disassembly/Assembly
A.

Trim Tab Actuator Disassembly (Refer to Figure 203).
(1) Remove the trim tab actuator. Refer to Tim Tab Actuator Removal/Installation.
(2) Turn the screw assembly to loosen and remove it from the actuator.

B.

Trim Tab Actuator Assembly (Refer to Figure 203).
(1) If a new bearing is necessary, press it into the boss on the screw assembly. Make sure that the
force pushes against the outer race of the bearing.
(2) Install the screw assembly into the actuator as follows:
(a) Pack the internal housing with MIL-G-21164C grease.
NOTE:

(3)
|

This supplies the lubrication for the screw assembly.

(b)
Install the screw assembly in the housing.
(c) If necessary, clean the unwanted grease from the housing.
Hold the screw assembly and turn the sprocket by hand to do a test of the actuator assembly.
NOTE:

The screw assembly must move smoothly in the actuator.

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MODEL 172
MAINTENANCE MANUAL

B

F
D
G
K

J
L

k
nFTAII

DETAIL

A

AFT

I

DETAIL M
RIGHI
FORW
CABLE

DETAIL R

DETAIL

B

DETAIL

D
0510T1007
A0563T2001
B0563T1016
D0563T1016
F0563T1011
F0563T3001
G0563T1016
J0563T1002
K0563T1003
L0563T1002
M0563T1016
P0513T1001
H0563 1001

CHAIN

Elevator Trim Tab Control System
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B1718

TAB UP

(/

TAB UP
A

-TAB DOWN

TAB DOWN

0~.Y:

DETAIL C

DETAIL Q
TAB UP

TAB DOWN
_

.

_

.

. _

AB UP

DETAIL

TAB DOWN

E

DETAIL N

TAB D(
TAB UP

DETAIL

H
C0563T1017
E0563T1017
H0563T1017
N0563T1017
Q0563T1017

Elevator Trim Tab Control System
Figure 201 (Sheet 2)

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MODEL 172
MAINTENANCE MANUAL

B1
.

.

CHAIN GUARD

CHAIN

UC I MIL r

0510T1007
A0563T1011
A0563T3001

Elevator Trim Tab Actuator Installation
Figure 202 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

C

ACTUATOR

DETAIL A

SCREW
ASSEMBLY

SEALED
BEARING

SPROCKET

DETAIL B
0510T1007
A0563T1010
B0563T1010

Elevator Trim Tab Actuator Cleaning and Inspection
Figure 203 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1721

CHORD LENGTH
HINGE
POINT

TRAILING
EDGE
TRIM TAB

DETAIL C

HINGE

TQA11 Mr-'r

EDGE

/

t
__

0

+

V

[]

FREE PLAY UP

*

NEUTRAL POSITION

0

FREE PLAY DOWN

A TOTAL FREE PLAY

C0563T1012

Elevator Trim Tab Actuator Cleaning and Inspection
Figure 203 (Sheet 2)

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MAINTENANCE MANUAL

4.

Trim Tab Actuator Cleaning and Inspection
A. Complete a Trim Tab Actuator Cleaning and Inspection (Refer to Figure 203).
(1) Remove the screw assembly from the housing. Refer to Trim Tab Actuator Disassembly/
Assembly.
(a) Do not remove the sealed bearing from the screw assembly unless the bearing replacement
is necessary.
(2) Wash the screw assembly, except the sealed bearing, in Stoddard solvent or equivalent. Do not
clean the sealed bearing.
(3) Examine the sealed bearing and screw assembly for wear and for parts that have scores. Refer
to Table 201 for dimensions.

Table 201. Actuator Wear Limits
COMPONENT

MAXIMUM DIMENSION

MINIMUM DIMENSION

Aft End Bearing Inside
Diameter

0.249 Inch

0.248 Inch

Screw Assembly
0.246 Inch (Shank)
0.245 Inch (Shank)
Outside Diameter
(4) Examine the screw assembly and the screw for threads that have damage or dirt particles that
can cause the assembly to operate incorrectly.
(5) Examine the screw assembly sealed bearing for smoothness of operation.
(6) Examine the housing components for stripped threads, cracks, deep nicks, dents, and other
signs of damage.
(7) Examine the sprocket for broken, chipped, and/or worn teeth.
(8) Examine the linear free play at the sprocket end of the housing.
NOTE:

The linear free play at the sprocket end must not be more than 0.010 inch maximum.

(a) If the free play is more than the permitted limits, replace the actuator.
(9) Do not try to repair the actuator assembly parts that have damage or wear.
(10) Install the screw assembly into the housing. Refer to Trim Tab Actuator Disassembly/Assembly.
5.

Trim Tab Free Play Inspection
A.

Do an Inspection for Trim Tab Free Play (Refer to Figure 203).
(1) Put the elevator and trim tab in the neutral position and keep the elevator from movement with
the elevator gust lock.
(2) Find the maximum amount of permitted free play.
(a) Measure the chord length at the inboard end of trim tab as shown in Detail C.
(b) Multiply the chord length by 0.025 to get the maximum permitted free play.
(c) Measure the free play at the same point on the trim tab that the chord length was measured.
(d) Make sure that the total free play is not more than the maximum permitted free play.
(3) Use a moderate hand pressure (up and down) to measure the free play at the trailing edge of
the trim tab.
(4) Ifthe trim tab free play is less than the maximum permitted free play, the system is in the permitted
limits.
(5) If the trim tab free play is more than the maximum permitted, examine the items that follow for
looseness while you move the trim tab up and down.
(a) Examine the push-pull channel to trim tab horn assembly attachment for looseness.
(b) Examine the push-pull channel to actuator assembly threaded rod end attachment for
looseness.
(c) Examine the actuator assembly threaded rod end for looseness in the actuator assembly.
(6) If looseness is apparent in the push-pull channel to trim tab horn assembly attachment or the
push-pull channel to actuator assembly threaded rod end attachment, repair with the installation
of new parts.

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MAINTENANCE MANUAL
(7) If looseness is apparent in the actuator-assembly threaded rod end, the screw assembly is out
of tolerance and you must replace it.
6.

7.

Trim Tab Control Wheel Removal/Installation
A.

Trim
(1)
(2)
(3)
(4)

Tab Control Wheel Removal (Refer to Figure 204).
Release the cable tension at the turnbuckle.
Remove the pedestal cover.
Remove the screws that attach the control wheel retainer.
Remove the retainer and the pointer. Hold the trim control wheel securely.

B.

Trim
(1)
(2)
(3)

Tab Control Wheel Installation (Refer to Figure 204).
Install the retainer and the pointer with the screws.
Install the pedestal cover.
Set the cable tension at the turnbuckle. Refer to Trim Tab Control Adjustment/Test.

Trim Tab Control Adjustment/Test

CAUTION: Put a support stand under the tail tiedown ring when you do work in the
tail of the airplane or the tailcone can fall.
A.

Set Trim Tab Control Cable Tension (Refer to Figure 205 and Figure 206).
(1) Remove the rear baggage compartment panel and the access plates as necessary.
(2) Loosen the travel stop blocks on the cables.
(3) Disconnect the actuator from the trim tab push-pull channel.
(4) Adjust the turnbuckle as necessary to get 15 to 20 pounds (66.72 to 88.96 N) of cable tension
at 70°F (21 °C). Refer to Figure 206 for the correct tensions at other temperatures.
NOTE:

For the installation of chains or cables, let the actuator screw turn freely, as chains
and cables are connected.

(5) Turn the trim wheel full forward. Make sure that the pointer does not limit wheel movement. If
necessary, move the pointer with a thin screwdriver to pry the trailing leg of the pointer out of
the groove.
(6) With the elevator and the trim tab in the neutral position, put an inclinometer on the tab and set
it at zero.
(7) Turn the actuator screw in or out as necessary to put the tab up with a maximum of two degrees
overtravel, with the actuator screw connected to the push-pull channel.
(8) Turn the trim wheel to put the tab up and down, and adjust the actuator screw as necessary to
get overtravel in the two directions.
(9) Put the stop blocks in position (standard configuration) (Refer to Figure 205).
(a) With the elevators in the neutral position, set the trim tab to neutral (streamlined).
(b) Put the stop blocks (2) and (3) approximately 0.25 inch forward and aft of the turnbuckle
and attach it to cable A.
(c) Put the inclinometer on the trim tab and run the tab to DOWN TRAVEL limit of 19 degrees,
+1 or -0 degree.
(d) Put the stop block (4) against the stop block (3) and attach it to cable B.
(e) Run the trim tab to UP TRAVEL limit of 22 degrees, +1 or -0 degree, place stop block (1)
against the stop block (2) and attach it to cable B.
(10) Put the stop blocks in position (configuration with optional dual-axis autopilot) (Refer to Figure
205).
(a) With the elevators in the neutral position, set the trim tab to neutral (streamlined).
(b) Put the stop block (3) approximately 1.0 inch forward of the turnbuckle, and attach it to
cable A.
(c) Put the inclinometer on the trim tab and run the tab to UP TRAVEL limit of 22 degrees, +1
or -0 degree.
(d) Put the stop block (2) against the stop block (3) and attach it to cable B.
(e) Run the trim tab to DOWN TRAVEL limit of 19 degrees, +1 or -0 degree, place the stop
block (1) against the stop block (2) and secure it to cable A.

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MODEL 172
MAINTENANCE MANUAL

I

A0563T1001

Elevator Trim Tab Wheel Installation
Figure 204 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B1723

CABLE A

CABI

.S;TnP
RI nr.K
1I
I * a-

TURNBUCKLE

STOP BLOCK 2

STOP BLOCK 4

BLOCK 3

0563T1013

Elevator Trim Tab Travel Adjustment
Figure 205 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

35i

| -4_(__

30---

._i

CO

-

ELEVATOR TRIM CABLES {0.094-INCH DIAMETER)

0

-

TENSION 17.5 POUNDS AT 70"

z 25
20
0

UPPER LIMIT

5-

Z

,~..
. w.I

_r

NOMI

-

i,

10
LOWER LIMIT

5
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.

.. ..

.. ..

I I I I II I II I II
-l0 -30 -20 -10

I

II I 1

I

10

0

I TI I

20

111 lIT 1 1 11 11 1 1 1 I

30

40

50

60

ll

I

70

- I-------11

80

I I II

90

1t0

100

DEGREES FAHRENHEIT

160
140^-120
u,

4

ij

ELEVATOR TRIM CAE
---TENSION 78 N AT 21

-~

100
u-4

s~80

J

11

i

l

U
fNOMtN

er

40
20
1il

0

-4

ill 1 ll 1II1

-35 -30

-25 -20

-15 -10

-5

0

5

10

15

20

25

30

35

40

45

DEGREES CELSIUS
Elevator Trim Cable Tension
Figure 206 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
Do a check of the pitch trim rigging.
1
Streamline the elevator and the trim tab. Put an inclinometer to the trim tab and set it
to 0 degrees. Manually move the trim tab to up and down limits and record the limits
of travel.
2
Put an observer at the bottom aft access opening in the tailcone. Apply power to
the aircraft and move the electric trim to full nose-up position until the observer sees
clutch slippage. With the servo clutch still slipping, apply an additional quarter turn of
the manual trim wheel nose-up (test load condition).
In this condition, the observer must make sure that the stop blocks do not slip on the
3
trim tab cables.
Release the trim wheel and disengage the autopilot. Manually move the trim to
4
full nose-up position and do a check of the trim tab deflection with an inclinometer.
Additional trim tab deflection (compared with the values that you recorded) shows
slippage of the stop blocks.
Do a rigging of the trim system.
5
Measure the torque on the stop block bolts and then do the check of the pitch trim
6
rigging
If the swaged ball needs adjustment, move the cable assembly chain on the gear
7
teeth of the actuator sprocket to make the adjustments. One chain link corresponds
to approximately 17 degrees of travel on the capstan. Tension the cable and do the
check of the pitch trim rigging again.
Do this procedure again for the full nose-down trim condition.
8
(11) Make sure that the trim wheel pointer travels the same distance from the ends of the slot in the
cover. If necessary, move the trailing leg of the pointer.
(f)

WARNING: Make sure that the trim tab moves in the correct direction
when you operate it with the trim wheel. The nose down trim
corresponds to the tab up position.
(12) Safety the turnbuckle and install all items removed to get access to the components.

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MODEL 172
MAINTENANCE MANUAL
STALL WARNING SYSTEM - MAINTENANCE PRACTICES
1.

General
A.

B.

2.

3.

The stall warning system includes a stall warning horn and a scoop assembly. The stall warning horn
is found on the inside of the cabin, behind the door post molding and to the outboard side of the pilot,
on the fuselage rib. The scoop assembly is installed on the leading edge of the left wing at WS 91.25.
The scoop assembly is operated by airflow over the surface of the wing. There is an internal reed
that will make a warning sound when the airspeed is approximately 4.5 to 9.0 knots faster than the
airplane stall speed.

Scoop Assembly Removal/Installation
A.

Remove the scoop assembly (Refer to Figure 201).
(1) Remove the screws that attach the wing strut fairing to the wing.
(2) Move the wing strut fairing to the center of the strut.
(3) Remove the access panel (510CB).
(4) Remove the screws from the outside of the wing that attach the scoop assembly to the inside
wing skin.
(5) Remove the clamp that connects the scoop assembly to the tube.
(6) Remove the scoop assembly from the airplane through the access panel (510CB).

B.

Install the scoop assembly (Refer to Figure 201).
(1) Put the scoop assembly in position against the wing skin through the access panel (510EB).
(2) Attach the tube to the scoop assembly with the clamp.
(3) Attach the scoop assembly to the inside of the wing skin with screws.
(4) Install the access panel (510CB).
(5) Move the wing strut fairing so that it is against the bottom of the wing.
(6) Install the screws that attach the wing strut fairing to the wing.

Stall Warning Horn Removal/Installation
A.

Remove the stall warning horn (Refer to Figure 201).
(1) Remove the scoop assembly. Refer to Scoop Assembly Removal/Installation.
(2) Remove the doorpost molding (LH). Refer to Chapter 25, Interior Upholstery - Maintenance
Practices.
(3) Remove the access panels (510AB and 510BB) from the wing.
(4) Remove the clamps and brackets from the tube through the access panels (51 OAB and 51OBB).
(5) Carefully remove the stall warning horn and tube from the wing through the cabin.

B.

Install the stall warning horn (Refer to Figure 201).
(1) Put the tube and stall warning horn into the wing through the upper door post shield.
(2) Install the clamps and brackets on the tube through the access panels (510AB and 510BB).
(3) Install the access panels (510AB and 510BB).
(4) Install the door post molding (LH). Refer to Chapter 25, Interior Upholstery - Maintenance
Practices.
(5) Install the scoop assembly. Refer to Scoop Assembly Removal/Installation.

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MODEL 172

MAINTENANCE MANUAL

M

^,^^

HORN ASSEMBLY

TUBE
T

CLAMP

TUBE

SCOOP PLATE

..

Ade

7

Is

A056rT1010

Stall Warning System Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
FLAP CONTROL SYSTEM - TROUBLESHOOTING
1.

Troubleshooting
NOTE:

Due to remedy procedures in the following chart, it may be necessary to re-rig the system after
trouble has been corrected.

TROUBLE

PROBABLE CAUSE

REMEDY

BOTH FLAPS FAIL TO
MOVE

Open circuit breaker.

Reset and check continuity.
Replace breaker if defective.

Defective switch.

Place jumper across switch.
Replace if defective.

Defective motor.

Remove and bench test motor.
Replace if defective.

Broken or disconnected wires.

Run a continuity check of wiring.
Connect or repair wiring.

Defective or disconnected
transmission.

Connect transmission. Remove,
bench test and replace
transmission if defective.

Defective limit switch.

Check continuity of switches.
Replace switches found defective.

Cables not riding on pulleys.

Check visually. Route cables
correctly over pulleys.

Bind in drive pulleys.

Check drive pulleys in motion.
Replace drive pulleys found
defective.

Broken or binding pulleys.

Check pulleys for free rotation or
breaks. Replace defective pulleys.

Frayed cable.

Check visually. Replace defective
cable.

Flaps binding on tracks.

Observe flap tracks and rollers.
Replace defective parts.

Disconnected or broken cable.

Check cable tension. Connect or
replace cable.

Disconnected push-pull rod.

Check visually. Attach push- pull
rod.

Incorrect rigging.

Rig correctly. Refer to Flap Control
System Adjustment/Test.

Defective operating switch.

Check continuity of switches.
Replace switches found defective.

BINDING IN SYSTEM
AS FLAPS ARE
RAISED AND
LOWERED.

LEFT FLAP FAILS TO
MOVE

INCORRECT FLAP
TRAVEL

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
TROUBLE

PROBABLE CAUSE

REMEDY

FLAPS FAIL TO
RETRACT

Defective or disconnected flaps UP
operating switch.

Check continuity of switch.
Connect or replace switch.

FLAPS FAIL TO
EXTEND

Defective or disconnected flaps DOWN
operating switch.

Check continuity of switch.
Connect or replace switch.

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CESSNA AIRCRAIFT COMPANY

MODEL 172
MAINTENANCE MANUAL
FLAP CONTROL SYSTEM

-

MAINTENANCE PRACTICES

1.General
A. The wing flap control system has an electric motor and transmission assembly, drive pulleys, push-pull
rods, cables, and a follow-up control. Power from the motor and the transmission assembly goes to
the flaps by a system of drive pulleys, cables, and push-pull rods. Electrical power to the motor is
controlled by two microswitches mounted on a floating arm assembly, a cam lever, and a follow-up
control. As the flap control lever moves to the necessary flap setting, the attached cam activates one
of the microswitches, and that activates the flap motor. As the flaps move to the necessary position,
the floating arm is turned by the follow-up control until the active microswitch clears the cam. The
circuit breaks and the motor stops. To move the flap in the opposite direction, the control lever is
moved in the opposite direction. This causes the cam to activate the second microswitch, which
changes the direction of the flap motor. The follow-up control moves the cam until it is clear of the
second switch, which stops the flap motor. Limit switches at the flap actuator assembly control flap
travel as the flaps get to the full UP or DOWN position.
B.
2.

For a schematic of the flap system, refer to Figure 201.

Flap Motor and Transmission Assembly Removal/installation
A.

B.

Flap
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Flap
(1)

Motor and Transmission Assembly Removal (Refer to Figure 202).
Lower the flaps.
Disconnect the electrical power.
Remove the access plate 61 0GB. Refer to Chapter 6, Access/Inspection Plates - Description
and Operation.
Remove the bolt that attaches the actuating tube to the drive pulley.
Turn the actuating tube in toward the transmission as far as possible by hand.
Remove the bolt that attaches the flap motor hinge to the wing.
Keep the brass washer that is installed between the hinge and the wing structure.
Disconnect the electrical connectors from the motor and the limit switches.
Carefully move the assembly from the wing through the access opening.
Motor and Transmission Assembly Installation (Refer to Figure 202).
Carefully move the assembly into the wing through the access opening.
NOTE:

If the hinge assembly was removed from the transmission, make sure that the short
end of the hinge is installed toward the top.

(2)
(3)
(4)
(5)
(6)

Connect the electrical connectors to the motor and the limit switches.
Attach the flap motor hinge to the wing with the bolt and the brass washer.
Turn the actuating tube out toward the bell crank.
Install the bolt that attaches the actuating tube to the drive pulley.
Install the access plate 610OGB. Refer to Chapter 6, Access/inspection Plates - Description and
Operation.
(7) Connect the electrical power.
(8) Do an operational check of the flaps. Refer to Flap System Adjustment/Test for the rigging
instructions.
3.

Flap Remova~l/nstallation
A.

Flap Removal (Refer to Figure 202).
(1) Make sure that the flap track slot width is 0.5735 inch +0.03 or -0.03 inch. If the width of the
flap track slot is not in these limits, you must replace the flap track.
(2) If necessary, apply 3M Y8671 (or equivalent) polyurethane tape to the upper flap skins. The
upper flap skins must not rub against the wing trailing edge.
(3) Put the Master Switch in the BAIT position and lower the flaps with the flap selector switch.
(4) Return the BATT portion of the Master Switch to the OFF position.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1724

FLAP MOTOR AND
TRANSMISSION

FWD

DRIVE PULLEY

DRIVE

SETSCREW

)R
3

Lt1-

RIGHT
PUSH-PULL
ROD

I

PUSH-PULL
ROD
TO LEFT
WING FLAP

TO RIGHT
WING FLAP

VIEW LOOKING DOWN

0525T1 007

Flap System Schematic
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B

3
C

D

TURNBUCKLE

DRIVE PULLI

Y
P

DETAIL

A

&---SCREW

BOLT

DETAIL

C

UAbLt UURhU

DETAILB
B

64I 1-4
64T 1004

Flap System Installation
Figure 202 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

21726

0.12 INCH, +0.05 OR -0.05 INCH

w

Flap System Installation
Figure 202 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B 1727

DETAIL

I

E

L-LJ%.J LI~J I

I %i

,CESS PLATE
ROLLER ASSEMBLY

/ BUSHING

BOLT
ROLLER
ASSEMBLY

PLATE
ACCESS PLATE
/SPACER
ASSEMBLY

FLAP
SUPPORT

DETAIL

H

INBOARD
ROLLER ASS EMBLYBUSHIN,
ACCESS PLATE

SUPPORT

OUTBOARD

G0564T1006A
H0525T 1005

Flap System Installation
Figure 202 (Sheet 3)

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MODEL 172
MAINTENANCE MANUAL

I

(5) Remove access panels 51liAT (61 1AT), 511 BT (611 BT), 511 CT (611 CT), and 511 DT (611 DT)
from the leading edge of the flap. Refer to Chapter 6, Access/Inspection Plates - Description

~

(6)
(7)
B.

I
4.

Flaps Installation (Refer to Figure 202).
(1) Install the flap to the flap tracks with the kept hardware.
(2) Connect the push-pull rod to the flap bracket.
(3) If the push-pull rod adjustment was changed during this procedure, you must do the rigging of
the flaps again. Refer to Flap Control Adjustment/Test.
(4) Install access panels 51 1AT (61 1AT), 511 BT (611 BT), 51liCT (611 CT), and 511 DT (611 DT) to
the leading edge of the flap. Refer to Chapter 6, Access/Inspection Plates - Description and

~

~~~Operation.

(5) Put the Master Switch in the BATT position and raise the flaps with the flap selector switch.
(6) Return the BATT portion of the Master Switch to the OFF position.
Flap Drive Pulley Removal/Installation
NOTE:
A.

Flap
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)

B.

5.

~~and
Operation.

Disconnect the push-pull rod at the flap bracket.
Remove the bolts at each flap track. As you remove the flap from the wing, all washers, rollers,
and bushings will fall free. Keep them.

Left and right flap drive pulley removal and installation are typical.
Drive Pulley Removal (Refer to Figure 202).
In the cockpit/cabin area, remove the overhead center console.
Remove the safety wire and loosen the flap adjustment turnbuckles.
Remove the access plate6l 0GB. Refer to Chapter 6, Access/Inspection Plates - Description and
Operation.
Remove the bolt that attaches the flap push-pull rod to the drive pulley and carefully lower the
right flap.
Remove the bolt that attaches the actuating tube to the drive pulley and carefully lower the left
flap.
Remove the cable locks that attach the control cables to the drive pulley. Tag the cables for
identification.
Remove the bolt that attaches the drive pulley to the wing structure.
Remove the drive pulley through the access opening. Do not drop the bushing.
Keep the brass washer that is installed between the drive pulley and the wing structure.

Flap Drive Pulley Installation (Refer to Figure 202).
(1) Install the drive pulley and the bushing through the access opening, install the brass washer,
and attach them to the wing structure with the bolt.
(2) Remove the tags and install the cable locks that attach the control cables to the drive pulley.
(3) Raise the left flap and install the bolt that attaches the actuating tube to the drive pulley.
(4) Raise the right flap and install the bolt that attaches the flap push-pull rod to the drive pulley.
(5) Do the rigging of the system. Refer to Flap Control Adjustment/Test.
(6) Install the access plate 61 0GB. Refer to Chapter 6, Access/Inspection Plates - Description and
Operation.
(7) Install the overhead center console.

Flap Control System Adjustment/Test
A.

Rigging of the Flap Control System (Refer to Figure 202 and Figure 203).
(1) In the cockpit/cabin area, remove the overhead console.
(2) With the flaps in the UP position, remove the clevis that attaches the follow-up cable to the bell
crank to disconnect the follow-up cable.
(3) Remove the safety wire, release the cable tension, disconnect the turnbuckles, and carefully
lower the left flap.
(4) Disconnect the push-pull rods at the drive pulleys in both wings and carefully lower the right flap.
(5) Disconnect the actuating tube from the drive pulley.

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0

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

Da2m

I

I

I

I

I

I
I
FLAP CABLES (0.094-INCH DIAMETER)

I
I
TENSKOtN 30 POUNDS AT 70 IF
I I
I
I
I

.I
.40

-0

.20

-10

0

10

20 30
DEGREES FAHRENHEIT

300
250

z
i9200

z
1i50
I100

0
-40 35-30 -25-20 -5

-10-5 0 5
10 15 20
DfE-GREES CELSIUS

26

30 3540 45

Flap Cable Tension
Figure 203 (Sheet 1)

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MAINTENANCE MANUAL
(6) Adjust both push-pull rods to 8.83 inches +0.12 or -0.12 inch between the centers of the rod end
bearings, and tighten the lock nuts on both ends. Connect the push-pull rods to the flaps and
the drive pulleys.
(7) If the control cables are not connected to the left and the right drive pulleys, you must disconnect
the actuating tube and the push-pull rods before you install the cables. If the drive pulleys are
not installed, you must attach the control cables before you install the drive pulleys in the wings.
(8) Turn the actuating tube in toward the transmission by hand to 0.12 inch +0.05 or -0.05 inch
between the switch actuating collar and the transmission.
(9) Temporarily connect the cables at the turnbuckles and test the flaps by hand to make sure that
the two flaps extend and retract together. If they do not, the cables are not correctly attached
to the drive pulleys. Make sure that the right drive pulley turns clockwise when you monitor it
from below, and extend the flaps. Put the tag on the cables for identification, and disconnect the
turnbuckles again.
(10) Loosen the setscrew that attaches the actuating tube to the switch actuating collar and hold
the collar to keep 0. 12 inch +0.05 or -0.05 inch while you hold the right flap up, and adjust the
actuating tube in or out as necessary to align it with the attachment hole in the drive pulley.
(11 ) Apply Loctite grade CV sealant to the threads of the setscrew and torque to 60 inch-pounds.
(12) Disconnect the push-pull rod at the drive pulley to let the connecting actuating tube drive the
pulley.
(13) Manually hold the right flap in the full up position and adjust the push-pull rod to align it with the
attachment hole in the drive pulley. Connect the push-pull rod and tighten the jam nuts.
(14) With the flaps in the full up position, loosen the setscrew and slide the up limit switch adjustment
block on support to just activate the switch and shut off the electrical power to the motor at this
position. Tighten the setscrew.
(15) Manually hold the left flap full up and connect the control cables at the turnbuckles. Remove the
tags that you installed for identification.
(16) Adjust the retract cable first. With the flaps up, adjust the turnbuckles to 30 pounds +10 or -10
pounds (133.45 N, +44.48 or -44.48 N) of tension on the cables at 70 OF (21 00). Refer to Figure
203 for the correct tensions at other temperatures.0
(17) Disconnect the push-pull rod at the left drive pulley.
(18) Run the motor to extend the flaps approximately 20 degrees and check the tension on each flap
cable.
(19) Adjust the turnbuckles as necessary to maintain 30 pounds +10 or -10 pounds (133.45 N +44.48
or -44.48 N) of tension on the cables at 70 OF (21 OC). Refer to Figure 203 for the correct tensions
at other temperatures.
(20) Fully retract the right flap.
(21) Manually hold the left flap in the up position and adjust the push-pull rod to align it with the attach
holes in the drive pulley.
(22) Connect the push-pull rod and tighten the lock nuts.
(23) Mount an inclinometer in the right flap and adjust to zero degrees.
(24) Run the flaps to the full down position and adjust the down limit switch to the stop motor and flap
at 30 degrees +0 or -2 degrees. Do the check on the left flap. Check the limit switch through
some flap cycles.
(25) Connect and do a rigging of the flap follow up system.
(26) Do an operational check of the system. Refer to the Operational Check.
(27) Check all items for correct safetying and install the items that you removed for access.
6.

Operational Check
A.

Operational Check Procedures
(1) Operate the flaps through their full range of travel, and look for uneven travel or jumpy motion,
binding, or lost motion. Make sure that the flaps move together through their full range of travel.
(2) Check for positive shut off of the motor at flap travel extremes to prevent damage to the actuator
assembly.
(3) With the flap full UP, mount an inclinometer on one flap and set to 0 degrees. Lower the flaps
to full DOWN position and check the flap angle as specified in Chapter 6, Airplane Dimensions
and Specifications - Description and Operation. Do this procedure again for the opposite flap.

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MODEL 172
MAINTENANCE MANUAL
FLAP FOLLOW UP AND INDICATING SYSTEM - MAINTENANCE PRACTICES
1.

Description and Operation
A.

2.

The flap follow up and indicating system consists of a sheathed cable assembly, pointers and micro
switches. One end of the cable is attached to the flap operating switch operating arm. The other
end is clamped to the flap direct cable, above the headliner in the rear cabin area. Motion of the flap
cable is transmitted through the follow up control to the pointer, attached to the switch mounting arm.
Pointer moves along a scale as the flaps are extended or retracted. When the motion of the switch
mounting arm with the attached operating switches positions the "active" operating switch to clear the
cam on flap lever, flap motor circuit is broken and flaps stop at selected position.

Follow Up and Indicating System Removal/Installation
A.

Figure 201 may be used as a guide for removal and installation of the flap follow up and indicating
system.
NOTE:

3.

If the knob on the flap selector lever becomes loose, remove knob and clean threads on
lever with methyl n-propyl ketone or equivalent. After threads have thoroughly dried, prime
threads and allow to dry. Secure knob to lever using loctite (MIL-S-22473) or equivalent.
Allow loctite to cure for approximately 30 minutes before returning to service.

System Rigging
A.

Rigging Procedures (Refer to Figure 201).
NOTE:

The flaps must be properly rigged before rigging the follow up system.

(1) Disconnect spring from switch mounting arm (Detail C).
(2) With flaps and flap lever in full UP position and holding flap position Indication to a clearance
of 0.03 inch maximum with top of instrument panel opening, pull center cable of flap follow up
cable (Detail B) to remove slack. Thread cable thru the clamp bolt (Detail C).
(3) Lubricate the slots of guide and bellcrank (Detail B) with LPS 3 or equivalent.
(4) Connect spring to switch mounting arm (Detail C).
(5) Adjust switches in slotted holes of mounting arm until cam is centered between switch rollers.
(6) Mount an inclinometer on one flap and set to 0 degrees. Turn master switch ON and move flap
lever to 10 degree position.
(7) Observe inclinometer reading when flap stops. Adjust flaps DOWN operating switch in slotted
holes on mounting arm as required to obtain flap travel of 10 degrees, + 0 or -2 degrees.
(8) Adjust flaps UP operating switch to obtain positive clearance with cam when flaps DOWN
operating switch has just opened in the 10 degree position.
(9) Repeat steps 6 thru 7 for the 20 degree flap position. Travel should be 20 degrees, +0 or -2
degrees.
(10) Run flaps to full DOWN position (30 degrees, +0 or -2 degrees). Ensure that flaps DOWN
operating switch remains closed as flap motor limit switch stops flaps in full DOWN position.
(11) Check flaps through several cycles, recheck all components for security, and replace items
removed for access.

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MODEL 172
MAINTENANCE MANUAL

B1
B

B

DETAIL A

ej

G
IOUNTING BRACKET
FOLLOW-UP
CABLE

ING
CKLE

DETAIL

B

0510T1007
A0564T1001
B0564T1003

Flap Indicator Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1729

;:VYVI
16nM
MOUNTING
AMOUNTING
ARM

FLAPS UP
OPERATING
SWITCH

DETAIL C

C0564T1002

Flap Indicator Installation
Figure 201 (Sheet 2)

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CHAPTER

FUEL

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

28-Title
28-List of Effective Pages
28-Record of Temporary Revisions
28-Table of Contents
28-00-00

Pages 1-2

Apr 7/2003

28-20-00

Pages 1-3

Jan 3/2005

28-20-00

Pages 201-223

Jul 1/2007

28-20-00

Pages 501-506

28-2 1-00

Pages 201 -218

Jul 1/2007
Apr 7/2003

©Cessna Aircraft Company

28 - LIST OF EFFECTIVE PAGES

Page 1 of 1
Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
FUEL

28-00-00
28-00-00
28-00-00
28-00-00

FUEL STORAGE AND DISTRIBUTION - DESCRIPTION AND OPERATION......
General...................................
FUEL STORAGE AND DISTRIBUTION - MAINTENANCE PRACTICES........
General...................................
Precautions.................................
Fuel Drain Valve Removal/Installation .....................
Fuel Level Sender Removal/Installation ....................
Fuel Level Indicator Removal/Installation....................
Fuel Reservoir Removal/installation......................
Fuel Selector Shaft Removal/Installation....................
Fuel Selector Valve Removal/Installation....................
Fuel Return Valve Removal/installation ....................
Fuel Shutoff Valve Control Cable/Arm Adjustment................
Electric Auxiliary Fuel Pump Removal/installation................
Fuel Bay Vents Adjustment/Test........................
Fuel Vent Check Valve Removal/Installation ..................
Vented Fuel Filler Cap Inspection .......................
Fuel Strainer Disassembly/Cleaning/Assembly .................
Auxiliary Fuel Pump Serviceable Test .....................
FUEL STORAGE AND DISTRIBUTION - ADJUSTMENT/TEST............
General...................................
Fuel Quantity Calibration And Check (Airplanes without Garmin G1000) .....
Fuel Quantity Calibration and Fuel Flow Test (Airplanes with Garmin G1000 with
software version 563.01 or earlier) .....................
Fuel Quantity Calibration and Fuel Flow Test (Airplanes with Garmin G1000 with
software version 563.02 or later) ......................

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-GENERAL ................................
Scope....................................
Tools, Equipment and Materials........................
Definition ..................................

FUEL BAY SEALING - MAINTENANCE PRACTICES ................
General...................................
Tools and Equipment.............................
Definition of Sealing Terms ..........................
Materials ..................................
General Requirements............................
Sealant Curing................................
Mixing of Sealants..............................
Cleaning ..................................
Sealing Application..............................
Sealant Repair................................
Classification of Fuel Leaks..........................
Sealing Fuel Leaks..............................
Testing Integral Fuel Bay...........................

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28 - CONTENTS
© Cessna Aircraft Company

Page
Page
Page
Page

Page
Page
Page
Page
Page
Page
Page
Page
Page
Page
Page
Page
Page
Page

201
201
201
204
205
206
207
207
209
209
215
216
218
218

Page 1 of 1
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
FUEL - GENERAL
1.

Scope
A.

2.

This chapter provides information on systems and componnets associated with fuel storage, fuel
distribution, refueling and fuel quantity indicating.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes may be used for the following items:

NAME

NUMBER

MANUFACTURER

USE

Sealant Type 1

CS-3204
Class A-1/2
Class A-2

Flame Master
Chem Seal Div.
11120 Sherman Way
Sun Valley, CA 91352

To seal fuel tank area.

Sealant Type 1

Pro-Seal 890
Class A-2

Courtaulds Aerospace
5426 San Femando Rd.
Glendale, CA 91209

To seal fuel tank area.

Sealant Type 1

PR-1440
Class A-1/2
Class A-2
Class B-2

Courtaulds Aerospace

To seal fuel tank area.

Sealant Type

Pro-Seal 890
Class B-1/2
Class B-2

Courtaulds Aerospace

To seal fuel tank area.

Sealant Type

PR-1440
Class B-1/2
Class B-2

Courtaulds Aerospace

To seal fuel tank area.

Sealant Type

PR-1826
Class B

Courtaulds Aerospace

To seal fuel tank area.

Sealant Type

CS-3204
Class B-1/2
Class B-2

Flame Master, Chem Seal Div.

To seal fuel tank area.

Sealant Type
VIII

PR-1428
Class B-1/2
Class B-2

Courtaulds Aerospace

To seal fuel tank access
panels.

Sealant Type
VIII

FR-1081
Class B-1/2
Class B-2

Fiber Resin Corp.
170 W. Providencia Ave.
Burbank, CA 91502

To seal fuel tank access
panels.

Pressure
Regulator

Commercially Available

To regulate input pressue.

Fahrenheit
Thermometer

Commercially Available

To monitor test area
temperature.

Eldorado Chemical Co. Inc.
14350 Lookout Road P.O.
Drawer 34837
San Antonio, TX 78265-4837

To locate source of leak.

Leak Detector

Eldorado LD-4

28-00-00
© Cessna Aircraft Company

Page 1

Apr 7/2003

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

NAME

NUMBER

MANUFACTURER

USE

Cleaner

Methyl
n-propyl

Commercially Available

To clean surfaces prior to
sealing.

ketone
Scotchbrite Pad

N/A

Commercially Available

To remove loose primer.

Fuel Quantity
Test Box

0580001-1

Cessna Aircraft Company

To calibrate fuel quantity
system.

680

Loctite

To improve the installation of
the fuel strainer fittings.

3.

Definition
A.

This chapter is divided into sections and subsections to assist maintenance personnel in locating,
specific systems and information. For locating information within the chapter, refer to the Table of
Contents at the beginning of the chapter.

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©Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
FUEL STORAGE AND DISTRIBUTION - DESCRIPTION AND OPERATION
1.

General
A.

The airplane has a wet wing fuel storage system. The system has two integral fuel tanks (one in each
wing), a three position selector valve, a fuel reservoir tank, an electrically-driven auxiliary fuel pump,
a fuel shutoff valve and a fuel strainer.

B.

Components forward of the fuel strainer include the engine-driven fuel pump, the fuel injection servo
and the fuel distribution valve. These components are part of the powerplant and are in Chapter
71, Engine - Description and Operation and in Chapter 73, Fuel Injection System - Description and
Operation.

C.

A schematic diagram of the fuel system is shown to help maintenance personnel know the system.
Refer to Figure 1.

28-20-00
©Cessna Aircraft Company

Page 1

Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1730

FUEL QUANTITY INDICATORS
F
C

TY
MITTER

RIGHT
FUEL
TANK

SELECTOF
VALVE
V

C
V

DRAIN

IR

TANK
AUXILIARYFUEL PUMP

AUXILIARY
FUEL PUMP
SWITCH
r;"

*I

.

-_

FUEL
STRAINER

~ENGINE DRIVEN
FUEL PUMP
FUEL INJECTION
SERVO

DRAIN
VALVE

TION
LEGEND

I . ..... I..

I

I

FUEL SUPPLY
VENT
MECHANICAL
LINKAGE
ELECTRICAL
CONNECTION

AIRPLANES
17280001 THRU
AND AIRPLANES
dj
I

7%OOQ fl4
n
-rTI
I/OOUU I I nnru

I

I I/o7-:Lu

0591R1001

Fuel System Schematic
Figure 1 (Sheet 1)

28-20-010
© Cessna Aircraft Company

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Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B3813

FUEL QUANTITY INDICATORS
FUEL
QUANTITY
TRANSMITTER

I

VALVES
(5 TOTAL)
DRAIN
VALVE

IIVALVE

FUEL RESERVOIR
TANK

0-T

It
1.
I

AUXILIARYFUEL PUMP
FUEL SHUTOFF
VALVE KNOB

-> -

P

'

FUEL
STRAINER

LEGEND

I
I
I

SERVO

I

FUEL SUPPLY

.-I

FUEL RETURN

VALVE

N

VENT
MECHANICAL
LINKAGE
ELECTRICAL
CONNECTION
ii'Ldui Jrlrn/

I

r

ODU'+--O-UO

0591R1001

Fuel System Schematic
Figure 1 (Sheet 2)

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© Cessna Aircraft Company

Page 3

Jan 3/2005

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
FUEL STORAGE AND DISTRIBUTION

-

MAINTENANCE PRACTICES

1.General
A.
2.

Precautions
A.

3.

This section gives information for the removal, installation and adjustment of fuel system components.
For an illustration of the fuel system, refer to Figure 201.

Obey the general precautions that follow and rules when fueling, defueling, fuel bay purging, repairing,
assembly or disassembly of system components, and electrical system checks and repairs on the
airplane fuel system.
(1) Plugs or caps must be placed on all disconnected hoses, lines and fittings to prevent residual
fuel drainage, thread damage, or entry of dirt or foreign material into fuel system.
(2) Any time the fuel system is opened, flush the system with 1/2 gallon of fuel at the inlet of servo
and flow divider with the fuel boost pump.
(3) When you do work on the fuel injection system, keep all the parts clean and free of contaminants.

Fuel Drain Valve Removal/installation
NOTE:

4.

Drain valve removal and installation is typical for all fuel drains on both wing tanks.

A.

Remove the Fuel Drain Valve (Refer to Figure 202).
(1) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(2) Use a fuel sampler cup to push the fuel drain valve up to make sure the fuel bay is drained.
(3) Cut the safety wire and remove the fuel drain valve from the fuel bay.

B.

Install the Fuel Drain Valve (Refer to Figure 202).
(1) Install the fuel drain valve in the fuel bay.
(2) Tighten the drain valve until the 0-ring compresses and makes a fuel-tight seat.
(3) Install safety wire on the drain valve. Refer to Chapter 20, Safetying - Maintenance Practices.
(4) Add a small quantity of fuel to the fuel bay and make sure the fuel drain valve does not leak.

Fuel Level Sender Removal/Installation
NOTE:

Fuel level sender removal/installation is typical for the left and right fuel bays.

A.

Make sure the fuel level sender operates correctly before the fuel quantity indicator is replaced.
(1) Make sure the resistance is 6 ohms, +5 or -5 ohms when the tanks are empty.
(2) Make sure the resistance is 90 ohms, +5 or -5 ohms when the tanks are full.

B.

Remove the Fuel Level Sender (Refer to Figure 203).
NOTE:

If the fuel level senders are replaced, the system must be calibrated. Refer to Fuel Quantity
Calibration.

(1)
(2)

Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
Remove access panels 510ODB and 51 OHB (left wing) or 61 0DB3 and 61OHB3 (right wing). Refer
to Chapter 6, Access/Inspection Plates - Description and Operation.
(3) Disconnect the wire ring terminals from the fuel level sender.
(4) Disconnect the fuel level sender ground wire from the wing rib.

CAUTION: Do not bend the fuel level sender float arm. A bent float arm will
give incorrect operation
(5) Remove the screws that attach the fuel level sender to the bracket.
(6) Carefully remove the fuel level sender from the fuel bay

28-20-00
© Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

0

FUEL SUPPLY
(RIGHT TANK)

REFER
FIGURE

AIRPLANES 17280001 THRU 17281187 AND
AIRPLANES 172S8001 THRU 172S9490
0510T1007
A0516TI005

Fuel System Installation
Figure 201 (Sheet 1)

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© Cessna Aircraft Company

Page 202
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B3810

FUEL SUPPLY
(RIGHT TANK)

DETAIL

A

AIRPLANES 17281188 AND ON, AND
AIRPLANES 172S9491 AND ON, AND
AIRPLANES THAT INCORPORATE SB04-28-01
A0516T1005A

Fuel System Installation
Figure 201 (Sheet 2)

28-20-00
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Page 203
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

1-1-

Ws
23.62

B

Ws
71 r,9

DETAIL

A

LOOKING UP AT BOTTOM OF WING
RIGHT SIDE SHOWN
(LEFT SIDE TYPICAL)

LOWER WING SKIN

DRAIN VALVE BOSS

FUEL DRAIN VALVE

0-RING

DETAIL

B

051OT1 007
A0516R 1016
B1516R 1017

Fuel Drain Valve Installation
Figure 202 (Sheet 1)

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©Cessna Aircraft Company

Page 204
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

.11-

B

MII IT

IK](-,

FUEL LEVEL SENDER

GASKET

ur-I

AIL-

-

LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)

I

DETAIL

kjL-L-

%IIAKITriTV 1K~r-ICrA-rn0

%aur"11

I I I

I

1114Lj1%ar%I %-II I

B

0510T1007
A0526T 1007
B0714T 1039

AIRPLANES WITHOUT GARMIN G1 000 OPTION
Fuel Level Sender
Figure 203 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
C.

Install the Fuel Level Sender (Refer to Figure 203).
NOTE:
(1)
(2)

If the fuel level senders are replaced, the system must be calibrated. Refer to Fuel Quantity
Calibration.

Install the new gaskets on the fuel level sender.
Install the five bushings into the mounting screw holes with the shoulder to the outside of the
transmitter.

CAUTION: Do not bend the fuel level sender float arm. A bent float arm will
give incorrect operation
(3) Carefully install the fuel level sender in the fuel bay.
(4) Attach the fuel level sender with screws and torque the screws to 20 inch-pounds.
(5) Connect the larger ring terminal to fuel level sender center stud (stud #1). Torque nut to 12
inch-pounds.
(6) Connect the fuel level sender ground wire to the small stud (stud #2).
(7) Install access panels 510ODB and 51 OHB (left wing) or 610ODB and 61 0HB (right wing). Refer to
Chapter 6, Access/Inspection Plates - Description and Operation.
(8) Do a check of the fuel quantity calibration. Refer to Fuel Quantity Calibration.
5.

Fuel Level Indicator Removal/installation
NOTE:
A.

B.

If the indicator is replaced, the system must be calibrated. Refer to Fuel Quantity Calibration.

Remove the Indicator (Refer to Figure 203).
(1) Make sure the electrical power is OFF.
(2) Get access to the forward of the fuel quantity indicator and disconnect the electrical connector.
(3) Remove the screws that attach the indicator to the instrument panel and remove the indicator
from the airplane.
Install the Indicator (Refer to Figure 203).
NOTE:

Fuel quantity calibration must be done after installing sender. Refer to Fuel Quantity
Cal ibration.

(1) Connect the electrical connector to the indicator.
(2) Put the indicator in position and attach to the instrument panel with screws.
(3) Make sure the fuel quantity gauge operates correctly.
6.

Fuel Reservoir Removal/installation
A.

Remove the Fuel Reservoir (Refer to Figure 204).
(1) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(2) Remove the copilot seat and carpet. Refer to Chapter 25, Front Seats and Rails - Maintenance
Practices and Chapter 25, Interior Upholstery - Maintenance Practices.
(3) Remove access panels 230BT and 230CT directly aft of the copilot rudder pedals to get access
to the reservoir. Refer to Chapter 6, Access/inspection Plates - Description and Operation .
(4) Put a container below the fuel drain in the fuselage.
(5) Drain the fuel from the reservoir.
(6) Disconnect the reservoir vent tube.
(7) Disconnect the reservoir inlet tube.
(8) Disconnect the reservoir outlet tube.
(9) Disconnect the line assembly on airplanes with the fuel return system,
(10) Remove the screws that attach the reservoir to the airplane structure.
(11) Remove the reservoir from the airplane.

B.

Install the Fuel Reservoir (Refer to Figure 204).
(1) Put the fuel reservoir in position and attach with the screws.

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© Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

FROM
SELECTOR
VALVE

TO AU)
FUEL P

JEL RESERVOIR
RAIN VALVE

DETAIL

A

AIRPLANES 17280001 THRU 17281187 AND
AIRPLANES 172S8001 THRU 1729490

01T10
A0516T 1004

Fuel Reservoir Installation
Figure 204 (Sheet 1)

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

0

83811

FUEL
RETURN
SYSTEM

-ROM
3ELECTOR
/ALVE

TO
FUE

EL RESERVOIR
1AIN VALVE

DETAIL

A

AIRPLANES 17281188 AND ON, AND
AIRPLANES 172S9491 AND ON, AND
AIRPLANES THAT INCORPORATE SB04-28-03
A0516T1004A

Fuel Reservoir Installation
Figure 204 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)

Connect the reservoir outlet tube.
Connect the reservoir inlet tube.
Connect the reservoir vent tube.
Connect the line assembly on airplanes with the fuel return system.
Make sure the fuel reservoir drain is closed.
Refuel the airplane. Refer to Chapter 12, Fuel - Servicing.
Put the fuel shutoff valve in the ON position.
Make sure the fuel reservoir connections do not have fuel leaks.
Operate the auxiliary fuel pump to make sure the fuel pressure gage has positive fuel pressure.
Install access panels 230BT and 230CT. Refer to Chapter 6, Access/Inspection Plates Description and Operation.
(12) Install the carpet and copilot seat. Refer to Chapter 25, Front Seats and Rails - Maintenance
Practices and Chapter 25, Interior Upholstery - Maintenance Practices.
7.

Fuel Selector Shaft Removal/installation
A. Remove the Fuel Selector Shaft (Refer to Figure 205).
(1) Make sure the fuel selector is in the BOTH position.
(2) Remove the plug button from the top of the fuel selector handle to get access to the screw.
(3) Remove the screw and washer from the top of the handle.
(4) Remove the pedestal cover and components to get access to the fuel shaft assembly.
(5) Remove the fuel selector placard from the pedestal.
(6) Remove the microphone mount bracket.
(7) Remove the fuel shut-off control knob.
(8) Disconnect the pedestal light.
(9) Remove the screws from the pedestal column.

CAUTION: Do not bend the pedestal cover too much when it is removed or it
will break.
(10)
(11)
(12)
(13)

B.

8.

Remove the pedestal cover.
Remove the support assembly.
Move the carpet as necessary to get to the floor access plate at the bottom of the pedestal.
Remove access panel 230FT to get access to the selector shaft assembly. Refer to Access!
Inspection Plates - Description and Operation.
(14) Remove and discard the cotter pin from the pin that attaches the selector shaft to the fitting.
(15) Remove the pin from the shaft assembly.
(16) Remove the selector shaft.
Install the Fuel Selector Shaft (Refer to Figure 205).
(1) Install the selector shaft into the fitting with the pin and a new cotter pin.
(2) Install access panel 230FT. Refer to Access/Inspection Plates - Description and Operation.
(3) Put the carpet in place.
(4) Install the selector shaft support.
(5) Install the pedestal cover.
(6) Connect the pedestal light.
(7) Install the fuel shut-off control knob.
(8) Install the fuel selector placard on the pedestal.
(9) Install the handle on the selector shaft with the washer, screw and plug button.
(10) Move the selector shaft to the LEFT, RIGHT and BOTH positions to make sure it operates
correctly.

Fuel Selector Valve Removal/installation
A.

Remove the Fuel Selector Valve (Refer to Figure 206).
(1) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(2) Remove the plug button from the top of the fuel selector handle to get access to the screw.
(3) Remove the screw and lift up on the handle to disconnect it from the fuel selector valve shaft.

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© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

PLUG BUTTON
r

)LE

A
PLACARD

SCI`

;NAP RING

UPPORT ASSEMBLY

WAII
LOCK

iP FITTING

'ELECTOR

COTT I
JiG

ECTOR
VE

DETAIL

A

0510T 1007
A0516R 1023

Fuel Selector Shaft
Figure 205 (Sheet 1)

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(DCessna Aircraft Company

Page 21 0
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(4) Remove the metal placard from the pedestal to get access to the valve, plumbing and universal
joints.
(5) Remove the carpet as applicable to get access to inspection plates aft of the pedestal structure.
Refer to Chapter 25, Interior Upholstery - Maintenance Practices
(6) Disconnect the fitting at the bottom of the shaft assembly from the valve shaft.
(7) Disconnect the fuel lines.
(8) Put caps on the fuel lines.
(9) Remove the screws that attach the valve to the bracket.
(110) Remove the valve.
B.

9.

Install the Fuel Selector Valve (Refer to Figure 206).
(1) Attach the selector valve to the bracket.
(2) Remove the caps and connect the fuel lines to the valve.
(3) Connect the valve shaft assembly.
(4) Refuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(5) Make sure the fuel lines do not leak.
(6) Install the inspection plates.
(7) Install the carpet. Refer to Chapter 25, Interior Upholstery - Maintenance Practices
(8) Install the metal placard to the center pedestal.
(9) Install the fuel selector valve handle to the shaft.
(10) Attach the fuel selector valve handle with the screw.
(11) Install the plug button.

Fuel Return Valve Removal/installation
A.

Remove the Fuel Return Valve (Refer to Figure 206).
(1) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(2) Remove the copilot seat and carpet. Refer to Chapter 25, Front Seats and Rails - Maintenance
Practices and Chapter 25, Interior Upholstery - Maintenance Practices.
(3) Remove access panels 230BT and 230CT directly aft of the copilot rudder pedals to get access
to the reservoir. Refer to Chapter 6, Access/Inspection Plates - Description and Operation.
(4) Put a container below the fuel drain in the fuselage.
(5) Drain the fuel from the reservoir.
NOTE:

Make a note of the arrow direction on the valve.

(6) Remove the valve.
(7) Put caps on the fuel return line assembly.
B.

Install the valve (Refer to Figure 206).
(1) Install the valve.
NOTE:

The arrow must point in the proper direction or fuel will not flow through the line
assembly.

(2)
(3)
(4)
(5)
(6)
(7)

Make sure the fuel reservoir drain is closed.
Refuel the airplane. Refer to Chapter 12, Fuel - Servicing.
Put the fuel shutoff valve in the ON position.
Make sure the fuel reservoir connections do not have fuel leaks.
Operate the auxiliary fuel pump to make sure the fuel pressure gage has positive fuel pressure.
Install access panels 230BT and 230CT. Refer to Chapter 6, Access/inspection Plates Description and Operation.
(8) Install the carpet and copilot seat. Refer to Chapter 25, Front Seats and Rails - Maintenance
Practices and Chapter 25, Interior Upholstery - Maintenance Practices.
10.

Fuel Shutoff Valve Control Cable/Arm Adjustment
A.

Adjust the Fuel Shutoff Cable and Control Arm (Refer to Figure 206).
(1) Remove the copilot seat. Refer to Chapter 25, Front Seats and Rails - Maintenance Practices.

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Page 211
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

----

LINE

FUEL
RESERVOIR
N

ELECTRIC
AUXILIARY
FUEL PUMP

.CTOR

TOR

I

B
FUEL
STRAINER

FUEL
SUIPPL
LINE

FUEL
SHUITOFF

VALVE
AIRPLANES 17280001 THRU 17281187 ANE
AIRPLANES 172S8001 THRU 1729490

)

5O10
A0510T1007

Fuel System Details
Figure 206 (Sheet 1)

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0

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B3812

FUEL
SUPPLY
FUEL VENT
LINE

FUEL

FUEL

ELECTRIC
FUEL PUMP

FOR

FIR
FIT

VALVE

B

I

FUEL

SHUTOFF

-Y

LINE
ASSEMBLY

FUEL
SELECTOR
VALVE

VALVE

FUEL
STRAINER

DETAIL

A

AIRPLANES 17281188 AND ON, AND
AIRPLANES 172S9491 AND ON, AND
AIRPLANES THAT INCORPORATE SB04-28-03

A0516T1007A

Fuel System Details
Figure 206 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B3263

LOCK NUT

RM

CLAMP

FUEL SHUTOFF
VALVE CABLE

DETAIL

B

B016T 10 14

Fuel System Details
Figure 206 (Sheet 3)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(2) Move the footwell carpet away from the copilot's rudder pedal shields to get access to the shield
screws.
(3) Remove the screws from the pedal shields.
(4) Remove the pedal shields from the airplane.
(5) Remove the lock nut.
NOTE:

Lock nuts can be used again unless they can be run-up finger tight.

NOTE:

When fiber-type self-locking nuts are used again, make sure the fiber locking function
has not decreased or become brittle.

(6)
(7)
(8)
(9)
(10)

Remove and replace the washers.
Install the lock nut and tighten to a minimum of 15 inch-pounds to attach the control cable.
Lubricate the swivel clamp with a dry film lubricant such as Molykote 321.
Make sure the control arm moves smoothly.
Operate the fuel shutoff control cable knob to make sure the fuel shutoff valve control cable/arm
connection moves smoothly.
(a) Adjust the control assembly until the connection operates smoothly.
(b) If adjustment does not give smooth operation, replace the assembly and adjust the control
assembly until it operates smoothly.
(11) Put the copilot's rudder pedal shields in position and attach with the screws.
(12) Install the footwell carpet.
(13) Install the copilot's seat. Refer to Chapter 25, Front Seats and Rails - Maintenance Practices.
11.

Electric Auxiliary Fuel Pump Removal/installation
A.

Remove the Electric Auxiliary Fuel Pump (Refer to Figure 206).
(1) Put the MASTER ALT/BAT switch to the OFF position.
(2) Disconnect the battery ground cable from the battery.
(3) Put the fuel selector handle to the fuel tank with less fuel.
(4) Defuel the fuel tank. Refer to Chapter 12, Fuel - Servicing.
(5) Remove the copilot seat and carpet. Refer to Chapter 25, Front Seats and Rails - Maintenance
Practices and Chapter 25, Interior Upholstery - Maintenance Practices.
(6) Remove access panels 230BT and 230CT. Refer to Chapter 6, Access/Inspection Plates Description and Operation.
(7) Disconnect the electrical connection (P1) from the electric auxiliary fuel pump (UIFOO5).
(8) Disconnect the fuel lines and drain line from the electric auxiliary fuel pump.
(9) Loosen the clamps that attach the electric auxiliary fuel pump.
(10) Remove the pump from the airplane.
(11) Remove all fuel fittings from the electric auxiliary fuel pump.
(12) Discard the inlet and outlet fuel fitting 0-rings.

B.

Install the Electric Auxiliary Fuel Pump (Refer to Figure 206).
(1) Put new 0-rings on the inlet and outlet fuel fittings.
(2) Install the inlet and outlet fuel fittings into the electric auxiliary fuel pump and tighten. Refer to
Chapter 20, Torque Data - Maintenance Practices.
(3) Install the fuel drain fitting into the electric auxiliary fuel pump and tighten. Refer to Chapter 20,
Torque Data - Maintenance Practices.
(4) Place the electric auxiliary fuel pump into the clamps.
(5) Loosely tighten the clamps.
(6) Connect the fuel lines to the inlet and outlet fittings and tighten by hand.
(7) Tighten the clamps. Refer to Chapter 20, Torque Data - Maintenance Practices.
(8) Tighten the fuel line fittings. Refer to Chapter 20, Torque Data - Maintenance Practices.
(9) Connect the electrical connection to the electric auxiliary fuel pump.
(10) Put the on/off valve to the OFF position.
(11) Put the fuel selector handle to the tank that has fuel.
(12) Make sure the electric auxiliary fuel pump and fuel fittings do not leak.
(13) Connect the battery ground cable to the battery.
(14) Loosen the fuel supply hose at the fuel injection servo inlet.

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(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)
12.

Put the mixture control to the OFF position.
Put the throttle control to the IDLE STOP position.
Put the on/off valve to the ON position.
Put the MASTER ALT/BAT switch to the ON position.
Put the FUEL PUMP switch to the ON position.
Operate the electric auxiliary fuel pump to bleed air from the fuel lines and prime the electric
auxiliary fuel pump.
Put the FUEL PUMP switch to the OFF position.
Put the MASTER ALT/BAT switch to the OFF position.
Tighten the fuel supply hose at the fuel injection servo inlet. Refer to Chapter 20, Torque Data Maintenance Practices.
Put the MASTER ALT/BAT switch to the ON position.
Put the FUEL PUMP switch to the ON position.
Operate the electric auxiliary fuel pump to make sure all fuel fittings do not leak.
Put the FUEL PUMP switch to the OFF position.
Put the MASTER ALT/BAT switch to the OFF position.
Install access panels 230BT and 230CT. Refer to Chapter 6, Access/Inspection Plates Description and Operation.
Install the carpet and copilot seat. Refer to Chapter 25, Front Seats and Rails - Maintenance
Practices and Chapter 25, Interior Upholstery - Maintenance Practices.

Fuel Bay Vents Adjustment/Test
NOTE:

If the fuel vent or vent bleed hole is blocked while the engine operates, the engine power can
decrease or stop because of a decrease in fuel supply.

NOTE:
A.

If the fuel vent or vent bleed hole is blocked while the engine does not operate, fuel expansion
can pressurize the fuel bays and cause fuel leaks.
Test the Fuel Bay Vents (Refer to Figure 207).
(1) Attach a rubber tube to the end of the vent line below the wing.
(2) Blow into the tube to pressurize the fuel bay.
NOTE:

The vent line is open if air can be blown into the fuel bay.

(3) After the tank is pressurized, put the end of the rubber tube in a container of water and look for
continuous bubbles.
NOTE:

Continuous bubbles show that the valve assembly bleed hole is open and that
pressure is released.

(4) Replace the fuel vent check valve if it does not operate correctly. Refer to Fuel Vent Check Valve
Removal/Installation.
(5) Loosen the filler cap on the opposite wing.
(6) Blow into the tube again to pressurize the fuel bay.
NOTE:
13.

The crossover line is open if pressure is released from the filler cap.

Fuel Vent Check Valve Removal/installation
A.

Remove the Fuel Vent Check Valve (Refer to Figure 208).
(1) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(2) Remove wing access panels 5l0KB and 6l0KBto get access to the fuel vent check valve. Refer
to Chapter 6, Inspection/Access Plates - Description and Operation.
(3) Remove the unserviceable fuel vent check valve.
(4) Put caps on the vent line.

B.

Install the Fuel Vent Check Valve (Refer to Figure 208).

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GROMMET

FAIR I

-*I
B

VIEw

A-A

IET

~~~~~~~vviI,,mu
~STRUT

RING

RING
VIEw

0510T1007
AA0526TI1008
H830526T1
008

B-B
Fuel Vent Location
Figure 207 (Sheet 1)

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LEFT FUEL
VENT LINE

DETAIL

BYPASS HOLE
(NOTE 1)

A

0
FUEL VENT
CHECK VALVE

DETAIL

C

(

LINE ASSEMBLY - VENT
NOTE 1: THE BYPASS HOLE MUST BE 11\N':
AT THE TOP OF THE FUEL BAY.

DETAIL

B

05lOT 1007
A1226R 1001
B1226R11004
C0516T1015

Fuel Vent Check Valve
Figure 208 (Sheet 1)

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WARNING: You must correctly align the fuel vent line below the wing near the
wing strut to prevent icing of the vent tube.
WARNING: You must correct any fuel vent component that is blocked or
restricted before the airplane returns to service.
(1) Remove the caps from the vent line.
NOTE:
(2)
(3)
(4)
(5)
(6)

The fuel vent check valve bypass hole on the valve flap must be at the top of the fuel
bay.

Install the new fuel vent check valve with the bypass hole on the valve flap at the top of the fuel
bay.
Install the wing access panels.
Do a test to make sure the fuel vent check valve operates correctly. Refer to Fuel Bay Vents
Adjustment/Test.
Refuel the airplane and make sure there are no leaks.
Make sure the fuel vent line below the wing is correctly aligned. Refer to Figure 207.

114. Vented Fuel Filler Cap Inspection
A.

Do an Inspection of the Vented Fuel Filler Cap (Refer to Figure 209).
(1) Remove the vented fuel filler cap from the adapter assembly.
(2) Disconnect the safety chain (if installed).
(3) Put a cover on the tank opening.
(4) Do a check of the gasket and frictionless washer.
(5) Replace the gasket and frictionless washer as required.

B.

Clean the rubber umbrella.
(1) Use cotton swabs and solvent to gently lift the edges of the rubber umbrella and to clean the
seat and the umbrella.
(2) Use a second swab to wipe the seat and umbrella thoroughly to remove cotton particles.
(3) Clean the rubber umbrella and seat until the swabs show no discoloration.

C.

Replace the umbrella if it leaks fuel or has deterioration.
(1) To remove the umbrella, lubricate the umbrella stem with hydraulic fluid (MIL-PRF-5606) to
prevent damage to the stem.
(2) To install the new umbrella, lubricate the stem with hydraulic fluid (MIL-PRF-5606) and use a
small blunt tool to insert the retaining knob on the umbrella into the check valve body.
Connect the fuel cap to safety chain (if installed) and install the cap in the adapter assembly.

D.
15.

Fuel Strainer Disassembly/Cleaning/Assembly
A. Disassemble and Clean the Fuel Strainer (Refer to Figure 210).
(1) Put the fuel selector valve in the off position.
(2) Disconnect and remove the safety wire, nut, and washer at the bottom of the filter bowl.
(3) Remove the bowl.
(4) Carefully remove the standpipe.
(5) Remove the filter screen and gasket.
(6) Wash the filter screen and bowl in solvent.
(7) Dry the filter screen with compressed air.
B.

Assemble the Fuel Strainer (Refer to Figure 21 0).
(1) Install a new gasket between the filter screen and top assembly.
(2) Install the screen.

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SCREW

lIfINVICM

=-L
CAP BODY

ASHER
fkSKET

'K VALVE

DETAIL

A

LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)

051OT1007
A0526R 1006

Vented Fuel Filler Cap
Figure 209 (Sheet 1)

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TOP
ASSEMBL'

GAS
0-RI
FILTER
ASSEME

STANDF

BOWI.

0-RIN'

NUT

0-RING
FUEL STRAINER
DRAIN VALVE

DETAIL

A

0510711007
A0516T 10
1

Fuel Strainer Assembly
Figure 210 (Sheet 1)

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(3) Install the standpipe finger tight.
NOTE:

The step-washer at the bottom of the bowl is installed so the step is against the 0ring. It is satisfactory to use 0-ring lubrication such as Dow Corning 4 (DC-4) Silicon
Grease, part number U000717.

(4) Install the bowl with new 0-rings. Torque the nut 25 to 30 inch-pounds.
NOTE:
(5)
(6)
(7)
(8)

16.

The safety wire must be twisted in the right hand direction with at least 45 degrees.

Safety wire the bottom nut to the top assembly.
Put the fuel selector valve in the on position and make sure there are no leaks.
Make sure the fuel selector valve operates correctly.
Bleed the air from the fuel strainer.
(a) Loosen the fuel supply hose at the fuel injection servo inlet.
(b) Set the mixture control to the OFF position.
(c) Set the throttle control to the IDLE STOP position.
(d) Set the FUEL PUMP switch to the ON position.
(e) Operate the electric auxiliary fuel pump until the air is removed from the fuel lines and the
electric auxiliary fuel pump is primed.
(f) Set the FUEL PUMP switch to the OFF position.
(g) Tighten the fuel supply hose at the fuel injection servo inlet. Refer to Chapter 20, Torque
Data - Maintenance Practices.

Auxiliary Fuel Pump Serviceable Test
A.

Do a Test of the Auxiliary Fuel Pump (Refer to Table 201).

WARNING: Obey all fuel system fire and safety procedures.
WARNING: Remove all flammable sources from the airplane and all vapor
hazard areas.
(1) Remove the fuel supply hose from the engine driven fuel pump inlet fitting.
(2) Install a T-fitting on the fuel supply hose.
(3) Connect a calibrated fuel pressure test gage and a locally purchased fuel shutoff valve to the
T-fitting.
(4) Point the fuel shutoff valve so it drains the fuel into a container.
(5) Use a multimeter to measure the electric current.
(6) Use a controlled electric power source to supply the 24 VDC electric power to the aircraft.
(a) Operate the auxiliary fuel pump and adjust the fuel shutoff valve to get a pressure value
as shown in Table 201 for the applicable part number to test.
(b) Monitor the current pull of the auxiliary fuel pump electric motor.
NOTE:
(c)

To help determine an acceptable pump output, the output will be 1 gallon in 2.5
minutes (24 GPH).

Measure the fuel pump current draw and pump output.
NOTE:

The Dukes Model 51 00-00-1 auxiliary fuel pumps that can give a minimum flow
rate of 23.5 GPH at 23 PSI and have a maximum current draw of 3.0 amps at
24 volts DC are serviceable.

NOTE:

Dukes Models 51 00-00-3 and 51 00-00-4 auxiliary fuel pumps that can give a
minimum flow rate of 23.5 GPH at 14 PSI and have a maximum current draw of
3.0 amps at 24 volts DC are serviceable.

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(7)
(8)

If the fuel pump does not meet the requirements, replace it with a pump that meets the
requirements.
If the fuel pump meets the requirements, it is serviceable.

Table 201. Dukes Model 5100 Serviceable Requirements
PUMP PART
NUMBER
________

FUEL FLOW
VOLUME
____

FUEL FLOW
PRESSURE

SUPPLIED
VOLTAGE

(M INIM UM )

MAXIMUM FUEL
PUMP CURRENT
_

_

_

_

5100-00-1 (or -1RX)

23.5 GPH

23 PSI

24 Volts DC

3.0 Amps

5100-00-3 (or -3RX)

23.5 GPH

14 PSI

24 Volts DC

3.0 Amps

51 00-00-4 (or -4RX)

23.5 GPH

14 PSI

24 Volts DC

3.0 Amps

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_

_

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(10) Use the EMS outer knob to go to the GEA page group.
(11) Use the EMS inner knob to go to the FUEL CALIBRATION page.

CAUTION: Ifthe Gl 000system has been turned off when the fuel was drained,
let the system become stable for a minimum of three minutes before
the calibration procedure is done.
NOTE:

The MFD will be in the configuration mode after the step that follows.

(12) Put the AVIONICS master switch to the ON position while the ENT button on the Multi-Function
Display (MFD) is held down.
(13) Release the ENT button after the words INITIALIZING SYSTEM show on the MED.
NOTE:

A password is required to do the calibration on the FUEL CALIBRATION page of the
FED.

(14) On the FUEL CALIBRATION page of the FED, push the softkeys in the sequence that follows
to input the password.
(a) Push Softkey 12 (far right softkey).
(b) Push Softkey 11 (R RESET).
(c) Push Softkey 10 (R FULL).
(d) Push Softkey 9 (R EMPTY).
(15) Make sure the FUEL FLOW ENG 1 SCALE value is 1.00000.
(a) Reset the system to 1.00000 if the value is not 1.00000. Refer to the Garmin G1 000 Line
Maintenance Manual.
(16) Push the L RESET softkey to set the left-hand calibration parameters to the default values.
NOTE:

When ENT is pushed to make the OK selection, the warning message "WARNING!
Pressing'OK'will cause calibration to revert to default settings" will be acknowledged.

(17) Push ENT to make the OK selection.
(18) Make sure the SLOPE of 1.00000e + 0.0 for the LEFT 1 SUB-TANK is shown.
(a) Do the fuel quantity system servicing if the SLOPE is not 1.00000 +0.0.
(19) Make sure the airplane is still level at two degrees nose up and zero degrees wings level attitude.
NOTE:

The CAL VAL value for the left tank must be stable.

(20) Make sure the CAL VAL value shown for the LEFT 1 SUB-TANK is stable.
(21) Push the L EMPTY softkey and make sure the SLOPE is no longer 1.00000e +0.0 for the LEFT
1 SUB-TANK.
(a) If the SLOPE is 1.00000e +/- 00, push the L EMPTY softkey again.
(b) If the SLOPE is still 1.00000e +/- 00, the fuel quantity system servicing must be done.
(22) Push the R RESET softkey to set the right-hand calibration parameters to the default values.
NOTE:

When ENT is pushed to make the OK selection, the warning message "WARNING!
Pressing 'OK'will cause calibration to revert to default settings" will be acknowledged.

(23) Push ENT to make the OK selection.
(24) Make sure the SLOPE of 1.00000e +/- 00 for the RIGHT 1 SUB-TANK is shown.
(a) Do the fuel quantity system servicing if the SLOPE is not 1.00000 +/- 00.
NOTE:

The CAL VAL value for the right tank must be stable.

(25) Make sure the CAL VAL value shown for the RIGHT 1 SUB-TANK is stable.
(26) Push the R EMPTY softkey and make sure the SLOPE is no longer 1.00000e +/- 00 for the

RIGHT 1 SUB-TANK.0

(a)

If the SLOPE is 1.00000e +1-00, push the R EMPTY softkey again.

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(b) If the SLOPE is still 1.00000e +/- 00, the fuel quantity system servicing must be done.

@
1

~

I

~~~~(27)
Make sure that the CAL VAL values are between -0.1 0 and 0.1 0 gallons (or -0.38 and 0.38 I) for
(a) Do the fuel quantity system servicing if the values are not in the range.
(28) Make sure that the CAL VAL values are between -0.1 0 and 0.1 0 gallons (or -0.38 and 0.38 I)for

~

(29)
(30)
(31)
(32)
(33)

~~the
RIGHT 1 SUB-TANK.

(a) Do the fuel quantity system servicing if the values are not in the range.
Put the AVIONICS master switch in the OFF position.
Put the BAT MASTER switch to the OFF position.
After a minimum of 10 seconds, put the BAT MASTER in the ON position.
Make sure the left "L" and right "R" fuel quantity pointers are on the red line.
(a) Do the fuel quantity system servicing if the values are not in the range.
Put the BAT MASTER switch to the OFF position.
NOTE:

The PFD will be in the configuration mode after the step that follows.

(34) Put the BAT MASTER switch to the ON position while the ENT button on the Primary Flight
Display (PFD) is held down.
(35) Release the ENT button after the words INITIALIZING SYSTEM show on the PFD.
NOTE:

The MFD will be in the configuration mode after the step that follows.

(36) Put the AVIONICS master switch to the ON position while the ENT button on the Multi-Function
Display (MFD) is held down.
(37) Release the ENT button after the words INITIALIZING SYSTEM show on the MFD.
(38) Add 8 gallons of fuel (low fuel level) to each fuel tank. Refer to Chapter 12, Fuel - Servicing.
(39) Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
(40) Let the airplane become stable for approximately 30 seconds.
(41) Make sure the airplane isstill level at two degrees nose up and zero degrees wings level attitude.
(42) Make sure the CAL VAL values are stable for the LEFT 1 SUB-TANK and RIGHT 1 SUB-TANK
on the PFD.
(43) Make sure the CAL VAL value for the LEFT 1 SUB-TANK is between 6.5 to 9 gallons.
(44) Make sure the CAL VAL value for the RIGHT 1 SUB-TANK is between 6.5 to 9 gallons.
(45) If the CAL VAL values are not in the range, move the wing tips again approximately 5 inches up
and down for approximately 10 seconds.
(46) Let the airplane become stable for approximately 30 seconds.
(47) Make sure the airplane is still level at two degrees nose up and zero degrees wings level attitude.
(48) Make sure the CAL VAL values are stable for the LEFT 1 SUB-TANK and RIGHT 1 SUB-TANK
on the PFD.
(49) Make sure the CAL VAL value for the LEFT 1 SUB-TANK is between 6.5 to 9 gallons.
(a) If the CAL VAL is still not in the range, drain the fuel from the tanks and do the fuel calibration
procedure again.
(50) Make sure the CAL VAL value for the RIGHT 1 SUB-TANK is between 6.5 to 9 gallons.
(a) If the CAL VAL is still not in the range, drain the fuel from the tanks and do the fuel calibration
procedure again.
(51) Put the AVIONICS switch to the OFF position.
(52) Put the BAT MASTER switch to the OFF position.
(53) After a minimum of 10 seconds, put the BAT MASTER in the ON position.
(54) Make sure the left "L"and right "R" fuel quantity pointers are near the top (right) of the yellow
range.
(a) If the values are in the range, the procedure is complete.
(b) If the values are not in the range, move the wing tips again approximately 5 inches up and
down for approximately 10 seconds.
(c) Let the airplane become stable for approximately 30 seconds.
(d) Make sure the airplane is still level at two degrees nose up and zero degrees wings level
attitude.
(e) Make sure the CAL VAL values are stable for the LEFT 1 SUB-TANK and RIGHT 1 SUB-

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Make sure the CAL VAL value for the
1
If the CAL VAL is still not in the
calibration procedure again.
(g) Make sure the CAL VAL value for the
If the CAL VAL is still not in the
1
calibration procedure again.
(f)

18.

LEFT 1 SUB-TANK is between 6.5 to 9 gallons.
range, drain the fuel from the tanks and do the fuel
RIGHT 1 SUB-TANK is between 6.5 to 9 gallons.
range, drain the fuel from the tanks and do the fuel

Fuel Strainer Disassembly/CleaninglAssembly
A.

Disassemble and Clean the Fuel Strainer (Refer to Figure 21 0).
(1) Put the fuel selector valve in the off position.
(2) Disconnect and remove the safety wire, nut, and washer at the bottom of the filter bowl.
(3) Remove the bowl.
(4) Carefully remove the standpipe.
(5) Remove the filter screen and gasket.
(6) Wash the filter screen and bowl in solvent.
(7) Dry the filter screen with compressed air.

B.

Assemble the Fuel Strainer (Refer to Figure 210).
(1) Install a new gasket between the filter screen and top assembly.
(2) Install the screen.
(3) Install the standpipe finger tight.
NOTE:

The step-washer at the bottom of the bowl is installed so the step is against the 0ring. It is satisfactory to use 0-ring lubrication such as Dow Corning 4 (DC-4) Silicon
Grease, part number U000717.

(4) Install the bowl with new 0-rings. Torque the nut 25 to 30 inch-pounds.
NOTE:
(5)
(6)
(7)
(8)

19.

The safety wire must be twisted in the right hand direction with at least 45 degrees.

Safety wire the bottom nut to the top assembly.
Put the fuel selector valve in the on position and make sure there are no leaks.
Make sure the fuel selector valve operates correctly.
Bleed the air from the fuel strainer.
(a) Loosen the fuel supply hose at the fuel injection servo inlet.
(b) Set the mixture control to the OFF position.
(c) Set the throttle control to the IDLE STOP position.
(d) Set the FUEL PUMP switch to the ON position.
(e) Operate the electric auxiliary fuel pump until the air is removed from the fuel lines and the
electric auxiliary fuel pump is primed.
(f) Set the FUEL PUMP switch to the OFF position.
(g) Tighten the fuel supply hose at the fuel injection servo inlet. Refer to Chapter 20, Torque
Data - Maintenance Practices.

Auxiliary Fuel Pump Serviceable Test
A.

Do a Test of the Auxiliary Fuel Pump (Refer to Table 201).

WARNING: Obey all fuel system fire and safety procedures.
WARNING: Remove all flammable sources from the airplane and all vapor
hazard areas.
(1) Remove the fuel supply hose from the engine driven fuel pump inlet fitting.
(2) Install a T-fitting on the fuel supply hose.
(3) Connect a calibrated fuel pressure test gage and a locally purchased fuel shutoff valve to the
T-fitting.

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IRI%7q

TO'
A S,

F
A

S

NUT

0-RING
FUEL STRAINER
DRAIN VALVE

DETAIL

A

0510T1007
A0516T 1010

Fuel Strainer Assembly
Figure 210 (Sheet 1)
©Cessna Aircraft Company

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(4) Point the fuel shutoff valve so it drains the fuel into a container.
(5) Use a multimeter to measure the electric current.
(6) Use a controlled electric power source to supply the 24 VDC electric power to the aircraft.
(a) Operate the auxiliary fuel pump and adjust the fuel shutoff valve to get a pressure value
as shown in Table 201 for the applicable part number to test.
(b) Monitor the current pull of the auxiliary fuel pump electric motor.
NOTE:
(c)

To help determine an acceptable pump output, the output will be 1 gallon in 2.5
minutes (24 GPH).

Measure the fuel pump current draw and pump output.
NOTE:

The Dukes Model 51 00-00-1 auxiliary fuel pumps that can give a minimum flow
rate of 23.5 GPH at 23 PSI and have a maximum current draw of 3.0 amps at
24 volts DC are serviceable.

NOTE:

Dukes Models 5100-00-3 and 5100-00-4 auxiliary fuel pumps that can give a
minimum flow rate of 23.5 GPH at 14 PSI and have a maximum current draw of
3.0 amps at 24 volts DC are serviceable.

If the fuel pump does not meet the requirements, replace it with a pump that meets the
requirements.
(8) If the fuel pump meets the requirements, it is serviceable.
(7)

Table 201. Dukes Model 5100 Serviceable Requirements
PUMP PART
NUMBER

FUEL FLOW
VOLUME

FUEL FLOW
PRESSURE

(MINIMUM)

MAXIMUM FUEL
PUMP CURRENT

SUPPLIED
VOLTAGE
_

_

_

_

_

_

_

5100-00-1 (or -lAX) 23.5 GPH

23 PSI

24 Volts DC

3.0 Amps

5100-00-3 (or -3RX)

23.5 GPH

14 PSI

24 Volts DC

3.0 Amps

510000-4(or -4RX)

23.5 GPH

14 PSI

24 Volts DC

3.0 Amps

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FUEL STORAGE AND DISTRIBUTION

-

ADJUSTMVENT/TEST

1.General
A.
2.

This section gives the adjustment/test procedures for the fuel storage and distribution system.

Fuel Quantity Calibration And Check (Airplanes without Garmin G1000)
A.

Fuel Indicator Calibration
(1) Put the fuel selector valve in the BOTH position.
(2) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(a) Open all the wing drain valves and drain the fuel bays until both are empty.
(b) Drain the fuel selector valve until empty.
(3) Put the fuel selector valve in the RIGHT position.
(4) Remove the fuel quantity indicator from the instrument panel.
(5) Install a 0580001 -1 test box between the wire harness connector and the fuel quantity indicator
connector.
NOTE:

The internal light for the fuel quantity indicator will not work when the test box is
connected.

(6) Make the airplane level.
(a) Make the wings level to 0.00 degree, +0.25 degree or -0.25 degree. Use blocks under the
wheels or adjust the tire pressure to make the wings level. Refer to Chapter 8, Leveling Maintenance Practices.
(b) Make the airplane level to 2.00 degrees, +0.25 or -0.25 degrees nose up position. Refer
to Chapter 8, Leveling - Maintenance Practices.
(7) Use an external power source to apply 28 VDC, +0.5 or -0.5 VDC, to the airplane, and put the
master switch in the ON position. Put both switches on the test box to the NORM position.
(8) Add unusable fuel to each fuel bay. Refer to Pilots'Operating Handbook for the amount of usable
fuel unusable fuel.
(9) Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
(10) Let the airplane become stable for approximately 30 seconds.
(11) Make sure that the airplane is still at 2 degrees nose up and the wings are still level.
(12) Adjust the "EMPTY" potentiometer, on the fuel quantity indicator, for the left and right gages until
the indicator pointer is in the middle of the red radial line.
NOTE:

A nonmagnetic screwdriver must be used when you adjust the potentiometers on the
fuel quantity indicator.

(13) Make sure that the low-fuel warning-lamps come on.
(14) Fill both fuel bays.
(15) Adjust the "FULL" potentiometer for the left and right gages until the pointer is in the middle of
the white radial line at the full indication.
(16) Make sure the low-fuel warning-lamps go off.
(17) Proceed to the Fuel Warning System Check.
B.

Fuel Warning System Check.
(1) Configure the airplane for the Fuel Warning System Check.
(a) Apply 28 VDC to the airplane.
(b) Set the master switch to ON.
(c) Move the test box switches to NORM.
(d) Make sure the fuel gages read FULL.
(e) Make sure the low-fuel annunciator is OFF.

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(2) Turn the NORM/OPEN switch on the text box to the OPEN position and start the timer.
NOTE:

The airplane's digital clock can be used in the timer mode to measure the time of the
annunciators. The interval for this test is from switch operation until the annunciator
begins to flash. The annunciators will flash for approximately 10 seconds before they
come continuously on without a flash.

(3) Monitor the fuel quantity indicator.
(a) Make sure the pointer goes to the power off position below the first graduation.
(b) The annunciators must come on within 75 seconds.
(4) Put the NORM/OPEN switch to the NORM position.
(a) The indicators must read full and the annunciators must go off.
(b) Set the timer again.
(5) Turn the SHORT/NORM/i100+ OHM switch to the 100+ OHM position. Start the timer.
(6) Monitor the fuel quantity indicator.
(a) Make sure the pointer goes to the power off position below the first graduation.
(b) The annunciators must come on within 75 seconds.
(7) Turn the SHORT/NORM/i100+ OHM switch to the NORM position.
(a) The indicators must read full and the annunciators must go off.
(b) Set the timer again.
(8) Turn the SHORT/NORM/i100+ OHM switch to the SHORT position. Start the timer.
(9) Monitor the fuel quantity indicator.
(a) Make sure the pointer goes to the power off position below the first graduation.
(b) The annunciators must come on within 75 seconds.
(10) Turn the SHORT/NORM/i 00+ OHM switch to the NORM position.
(a) The indicators must read full and the annunciators must go off.
(ii1) Set the airplane digital clock back to the clock mode.
(12) Set the master switch to OFF.
(13) Remove the test box.
(14) Install the fuel quantity indicator in the instrument panel.
(15) Set the master switch to ON.
(16) Make sure the fuel quantity indicators show FULL and the annunciators are off.
(17) Set the master switch to OFF.
3.

Fuel Quantity Calibration and Fuel Flow Test (Airplanes with Garmin G1000 with software version
563.01 or earlier)
NOTE:

The software version is shown on the upper right corner of the MED on the first page displayed
after power is applied the MVFD in normal operation.

NOTE:

If the fuel quantity indicator on the Garmin G1000 system has a red X on it during normal
operation, examine the sender and wiring and refer to the Garmin G1000 Line Maintenance
Manual for more Garmin system troubleshooting. If the values given on the Primary Flight
Display (PFD) are not the same as the values given in the calibration procedure, refer to the
Garmin G1000 Line Maintenance Manual for troubleshooting.

A.

Do a Fuel Quantity Calibration and Fuel Flow Test.
(1) Put the selector valve in the BOTH position.
(2) Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(a) Drain the fuel tanks with all wing drain valves until the two tanks are empty.
(b) Drain the fuel-selector drain valve until it is empty.
(3) Put the fuel selector valve in the RIGHT position.
(4) Make the airplane level.
(a) Make the wings level to 0.0 degrees, +0.25 or -0.25 degree. Use blocks under the wheels or
adjust the tire pressure to make the wings level. Refer to Chapter 8, Leveling - Maintenance
Practices.
(b) Make the airplane level to 2.00 degrees, +0.25 or -0.25 degree, in the nose up position.
Refer to Chapter 8, Leveling - Maintenance Practices.

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(5) Add unusable fuel to each fuel tank. Refer to the Pilot's Operating Handbook for the amount of
usable fuel.
(6) Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
(7) Let the airplane become stable for approximately 30 seconds.
(8) Put the BAT MASTER switch to the ON position while you push the ENT button on the PFD.
(9) Release the ENT button after the words INITIALIZING SYSTEM show on the PFD.
NOTE:

The PFD is now in the configuration mode.

(10) Use the Flight Management System (EMS) outer knob to go to the CAL page group.
(11 ) Use the EMS inner knob to go to the FUEL CALIBRATION page.
(12) Put the AVIONICS master switch in the ON position while you hold down the ENT button on the
MFD.
(13) Release the ENT button after the words INITIALIZING SYSTEM show on the MED.

CAUTION: Before you do the calibration procedure, you must turn on the
G1000 system and let it become stable for a minimum of three
minutes.
NOTE:

The MED is now in the configuration mode.

(14) Push the softkeys on the FUEL CALIBRATION page of the PED, in the sequence that follows,
to enter the password.
(a) Push Softkey 12 (far right softkey).
(b) Push Softkey 11.
(c) Push Softkey 10.
(d) Push Softkey 9.
(15) Make sure that the FUEL FLOW ENG 1 SCALE value is 1.00000.
(a) If the FUEL FLOW ENG 1 SCALE value is not 1.00000, use the EMS knobs to make it
1.00000. Push in the inner EMS knob to activate the cursor. Use the outer EMS knob to
select FUEL FLOW ENG 1 SCALE. Use the inner EMS knob to change the value.
(16) Push the L RESET softkey to set the left calibration parameters to the default values.
NOTE:

When L RESET is pushed, the system shows the warning message "WARNING!
Pressing 'OK' will cause the calibration to revert to the default settings."

(17) Push ENT to make the OK selection.
(18) Make sure that the airplane is level at 2.0 degrees nose up position and 0.0 degrees wings level
attitude.
(19) Make sure that the CAL VAL value shown for the LEFT 1 SUB-TANK is stable.
(20) Push the L EMPTY softkey.
(21) Push the R RESET softkey to set the right calibration parameters to the default values.
NOTE:
(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)

When R RESET is pushed, the system shows the warning message "WARNING!
Pressing 'OK' will cause calibration to revert to default settings."

Push ENT to make the OK selection.
Make sure that the CAL VAL value shown for the RIGHT 1 SUB-TANK is stable.
Push the R EMPTY softkey.
Make sure that the CAL VAL values are between -0. 10 and +0. 10 gallon ( -0.38 and +0.381) for
the LEFT 1 SUB-TANK.
Make sure that the CAL VAL values are between -0.1 0 and +0.1 0 gallon ( -0.38 and +0.381) for
the RIGHT 1 SUB-TANK.
Put the AVIONICS master switch in the OFF position.
Put the BAT MASTER switch in the OFF position.
After a minimum of 10 seconds, put the BAT MASTER switch in the ON position.
Make sure that the left, L, and right, R, fuel quantity pointers are on the red line.

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(31)
(32)
(33)
(34)
(35)
(36)

Put the BAT MASTER switch in the OFF position.
Put the BAT MASTER switch to the ON position while the ENT button on the PFD is held down.
Release the ENT button after the words INITIALIZING SYSTEM show on the PFD.
Use the EMS outer knob to go to the CAL page group.
Use the EMS inner knob to go to the FUEL CALIBRATION page.
Put the AVIONICS master switch to the ON position while the ENT button on the MED is held
down.
(37) Release the ENT button after the words INITIALIZING SYSTEM show on the MED.

CAUTION: Before you do the calibration procedure, you must turn on the
G1000 system and let it become stable for a minimum of three
minutes.
(38)
(39)
(40)
(41)
(42)
(43)
(44)
(45)
(46)
(47)
(48)
(49)

(50)
(51)
(52)
4.

Add 5 gallons of fuel (low fuel level) to the left fuel tank. Refer to Chapter 12, Fuel - Servicing.
Make sure the fuel is sensed in the LEFT 1 SUB-TANK.
Add 5 gallons of fuel (low fuel level) to the right fuel tank. Refer to Chapter 12, Fuel - Servicing.
Make sure the fuel is sensed in the RIGHT 1 SUB-TANK.
Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
Let the airplane become stable for approximately 30 seconds.
Make sure that the airplane is level at 2.0 degrees nose up position and 0.0 degrees wings level
attitude.
Make sure the CAL VAL values are stable for the LEFT 1 SUB-TANK and RIGHT 1 SUB-TANK
on the PFD.
Make sure the CAL VAL value for the LEFT 1 SUB-TANK is between 2.5 to 5 gallons.
Make sure the CAL VAL value for the RIGHT 1 SUB-TANK is between 2.5 to 5 gallons.
If the values are in the tolerance range, the procedure is complete.
If the CAL VAL values are not in tolerance:
(a) Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
(b) Let the airplane become stable for approximately 30 seconds.0
(c) Make sure that the airplane is level at 2.0 degrees nose up position and 0.0 degrees wings
level attitude.
(d) Make sure the CAL VAL values are stable for the LEFT 1 SUB-TANK and RIGHT 1 SUBTANK on the PFD.
(e) Make sure the CAL VAL value for the LEFT 1 SUB-TANK is between 2.5 to 5 gallons.
1
If the CAL VAL is still not in the tolerance range, drain the fuel from the tanks and do
the fuel calibration procedure again.
(f) Make sure the CAL VAL value for the RIGHT 1 SUB-TANK is between 2.5 to 5 gallons.
1
If the CAL VAL is still not in the tolerance range, drain the fuel from the tanks and do
the fuel calibration procedure again.
Inflate the tire to the correct pressure.
Put the AVIONICS switch to the OFF position.
Put the BAT MASTER switch to the OFF position.

Fuel Quantity Calibration and Fuel Flow Test (Airplanes with Garmin G1000 with software version
563.02 or later)
NOTE:

The software version is shown on the upper right corner of the MED on the first page displayed
after the MED is powered on in normal operation.

NOTE:

If the fuel quantity indicator on the Garmin G1000 system has a red X on it during normal
operation, examine the fuel quantity sender and wiring and refer to the Garmin G1000 Line
Maintenance Manual for more Garmin system troubleshooting. If the values given on the PFD
are not the same as the values given in the calibration procedure, refer to the Garmin G1lOQO
Line Maintenance Manual for troubleshooting.

A.

Do a Fuel Quantity Calibration and Fuel Flow Test.
(1) Put the selector valve in the BOTH position

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(2)
(3)
(4)

(5)
(6)
(7)
(8)
(9)

Defuel the airplane. Refer to Chapter 12, Fuel - Servicing.
(a) Drain the fuel tanks with all wing drain valves until the two tanks are empty.
(b) Drain the fuel-selector drain valve until it is empty.
Put the fuel selector valve in the RIGHT position.
Make the airplane level.
(a) Make the wings level to 0.0 degrees, +0.25 or -0.25 degree. Use blocks under the wheels
or adjust tire pressure to make the wings level. Refer to Chapter 8, Leveling - Maintenance
Practices.
(b) Make the airplane level to 2.00 degrees, +0.25 or -0.25 degrees nose up position. Refer
to Chapter 8, Leveling - Maintenance Practices.
Add unusable fuel to each fuel tank. Refer to the Pilot's Operating Handbook for the unusable
fuel quantity.
Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
Let the airplane become stable for approximately 30 seconds.
Put the BAT MASTER switch to the ON position while you push the ENT button on the PFD.
Release the ENT button after the words INITIALIZING SYSTEM show on the PED.
NOTE:

The PED is now in the configuration mode.

(10) Use the Flight Management System (FMS) outer knob to go to the CAL page group.
(11) Use the FMS inner knob to go to the FUEL CALIBRATION page.
(12) Put the AVIONICS master switch in the ON position while you hold down the ENT button on the
Multi-Function Display (MFD).
(13) Release the ENT button after the words INITIALIZING SYSTEM show on the MFD.

CAUTION: Before you do the calibration procedure, you must turn on the
G1000 system and let it become stable for a minimum of three
minutes.
NOTE:

The MFD is now in the configuration mode.

(14) Use the FMS outer knob to go to the GRS page group on the MFD.
(15) Use the FMS inner knob to go to the GRS/GMU CALIBRATION page on the MFD.
(16) Push the softkeys on the FUEL CALIBRATION page of the PFD, in the sequence that follows,
to enter the password.
(a) Push Softkey 12 (far right softkey).
(b) Push Softkey 11.
(c) Push Softkey 10.
(d) Push Softkey 9.
(17) Make sure that the FUEL FLOW ENG 1 SCALE value is 1.00000.
(a) If the FUEL FLOW ENG 1 SCALE value is not 1.00000, use the EMS knobs to make it
1.00000. Push in the inner FMS knob to activate the cursor. Use the outer EMS knob to
select FUEL FLOW ENG 1 SCALE. Use the inner FMS knob to change the value.
(18) Push the TNK SEL softkey to highlight the CURRENT TANK field.
(19) Turn the inner FMS knob to select LEFT.
(20) Make sure that the airplane is level at 2.0 degrees nose up and 0.0 degrees wings level attitude.
(21) Make sure that the CALIBRATED TOTAL value shown for the LEFT TANK is stable.
(22) Push the EMPTY softkey and press the enter (ENT) button to add the calibration point to the
CALIBRATION TABLE.
(23) Make sure that the CALIBRATED TOTAL values are between -0.10 and +0.10 gallon ( -0.38 and
+0.381) for the LEFT TANK.
(24) Push the TNK SEL softkey to highlight the CURRENT TANK field.
(25) Turn the inner FMS knob to select RIGHT.
(26) Make sure that the CALIBRATED TOTAL value shown for the RIGHT TANK is stable.
(27) Push the EMPTY softkey and press the ENT button to add the calibration point to the
CALIBRATION TABLE.

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(28) Make sure that the CALIBRATED TOTAL values are between -0.10 and +0.10 gallon (-0.38 and
+0.381) for the RIGHT TANK.
(29) Make sure there is only one calibration point in the CALIBRATION TABLE. Under ACTUAL
QUANTITY you must have "0.00 GL" and you must have one number under CALIBRATED
VALUE. If you have more points in the CALIBRATION TABLE highlight them and push the
DELETE softkey.
(30) Make sure that the left, L, and right, R, fuel quantity pointers are on the red line on the MED on
the GRS group GRS/GMU CALIBRATION page.
(31) Add 5 gallons of fuel (low fuel level) to the left fuel tank. Refer to Chapter 12, Fuel - Servicing.
(32) Make sure fuel is sensed in the LEFT TANK.
(33) Add 5 gallons of fuel (low fuel level) to the right fuel tank. Refer to Chapter 12, Fuel - Servicing.
(34) Make sure fuel is sensed in the RIGHT TANK.
(35) Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
(36) Let the airplane become stable for approximately 30 seconds.
(37) Make sure that the airplane is level at 2.0 degrees nose up and 0.0 degrees wings level attitude..
(38) Make sure the CALIBRATED TOTAL value for the LEFT TANK is stable and between 2.5 to 5
gallons.
(39) Make sure the CALIBRATED TOTAL value for the RIGHT TANK is stable and between 2.5 to 5
gallons.
(40) If the values are in tolerance, the procedure is complete.
(41) If the CALIBRATED TOTAL values are not in the range:
(a) Move the wing tips approximately 5 inches up and down for approximately 10 seconds.
(b) Let the airplane become stable for approximately 30 seconds.
(c) Make sure that the airplane is level at 2.0 degrees nose up and 0.0 degrees wings level
attitude.
(d) Make sure the CALIBRATED TOTAL value for the LEFT TANK is stable and between 2.5
to 5 gallons.
1
If the CALIBRATED TOTAL is still not in the tolerance range, drain the fuel from the
tanks and do the fuel calibration procedure again.
(e) Make sure the CALIBRATED TOTAL value for the RIGHT TANK is stable and between 2.5
to 5 gallons.
1
If the CALIBRATED TOTAL is still not in the tolerance range, drain the fuel from the
tanks and do the fuel calibration procedure again.
(42) Inflate the tire to the correct pressure.
(43) Put the AVIONICS switch to the OFF position.
(44) Put the BAT MASTER switch to the OFF position.

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MAINTENANCE MANUAL
FUEL BAY SEALING - MAINTENANCE PRACTICES
1.

General
A.

2.

The fuel bays may need to be resealed if a leak has developed, or if the wing has been repaired. This
procedures provides instructions for sealing fuel bays, classifying fuel leaks and testing fuel bays after
repair.

Tools and Equipment
NOTE:

Specified sealants, cleaning solvents, parting agents, adhesion inhibitors and equipment are
listed for use. Suitable substitutes may be used for sealing equipment only.
SEALANTS TYPE I, CLASS A- 1/2, OR A-2 - AMS-S-8802

NAME

NUMBER

MANUFACTURER

USE

Sealants

GC-408

Goal Chemical Sealant Corp.
3137 East 26th Street
Los Angeles, CA 90023

Fuel, pressure and
weather sealant brush
application.

Pro-Seal 890

Courtaulds Aerospace
5426 San Fernando Rd.
Glendale, CA 91209

PR-1422

Courtaulds Aerospace

PR-1440

Courtaulds Aerospace

MC-236

Morton Aerospace
Polymer Systems
9341 Anaconda Ave.
Garden Grove, CA 92641

SEALANTS TYPE I, CLASS B-1/4, QUICK REPAIR - MIL-S-83318
Sealant

GC-435

Goal Chemical Sealant Corp.

Fuel, pressure and
weather sealant. For
limited repairs requiring
rapid curing sealant.

SEALANTS TYPE I, CLASS B-1/2, B- 2 OR B-4 - AMS-S-8802
NAME

NUMBER

MANUFACTURER

USE

Sealants

GC-408

Goal Chemical Sealant Corp.

Fuel, pressure and
weather sealant spatula,
faying seals application.

Pro-Seal 890

Courtaulds Aerospace

PR-1422
Class B-1/2
Class B-2

Courtaulds Aerospace

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SEALANTS TYPE I, CLASS B-1/2, B- 2 OR B-4 - AMS-S-8802
NAME

NUMBER

MANUFACTURER

PR-1440
Class B-2
Class B-4

Courtaulds Aerospace

PR-1826

Courtalds Aerospace

MC-236

Morton Aerospace
Polymer Systems

USE

SEALANTS TYPE I, CLASS C- 20, C-48 OR C-80
Sealant

Pro-Seal 890

Courtaulds Aerospace

Fuel, pressure and
weather sealant. Suitable
for faying surface sealing.

SEALANT TYPE VIII
Sealant

PR-1428 Class
B2

Courtaulds Aerospace

PR-1081 Class
B2

Courtaulds Aerospace

Used in areas for access.

CLEANING SOLVENTS
NAME

NUMBER

MANUFACTURER

USE

1, 1, 1Trichloroethane
Technical
Inhibited (Methyl
Chloroform)

Federal
Specification
ASTM D4126

Commercially Available

Presealing cleaning.

Methyl-EthylKetone

Federal
Specification
TT-M-261

Commercially Available

Cleaning organic coating.

Naphtha Type II

Federal
Specification
TT-N-95

Commercially Available

Presealing cleaning.

Cleaning
compound

A-A-59281

Commercially Available

Presealing cleaning.

Isopropyl alcohol

Federal
Specification
TT-I-735

Commercially Available

Cleaning plastic
transparencies.

PARTING AGENTS
NAME

NUMBER

MANUFACTURER

USE

Silicone compound

AS 8660

Commercially available

Prevent sealant sticking.

Petrolatum
technical

Federal
Specification
VV-P-236

Commercially available

Prevent sealant sticking.

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MAINTENANCE MANUAL
EQUIPMENT
Pneumatic sealing
gun.

Semco
Number
250 with
accessories
(or equivalent)

Semco
Packaging
and
Applications Systems,
Division of Courtaulds Aerospace
5454 San Fernanco Rd.
Glendale, CA 91209

Injection sealing.

Hand-operated
sealing gun

Semco
Number 850

Semco
Packaging
and
Applications Systems,
Division of Courtaulds Aerospace

Injection sealing.

Semco
Packaging
and
Applications Systems,
Division of Courtaulds Aerospace

Application of sealant.

Polyethylene
cartridges with
plungers and caps
for sealant gun.

Commercially available

Application of sealant.

Metal spatulas with
either stainless
steel or glass
plates.

Commercially available

Mixing sealant.

Plastic lined cups,
wax-free with caps

Commercially available

Mixing sealant.

Sealant fairing
tools

Commercially available

To fair-in sealant.

Cheesecloth,
lint-free

Commercially available

Cleaning.

Plastic scraper,
45-degree cutting
edge.

Commercially available

Removing old sealant.

Rex Gauge Company, Inc.
3230 West Lake Avenue P.O. Box
46
Glenview, IL 60025

Testing cure of sealant.

Commercially available

Removing old sealant.

Nozzles,

Round 1/16 orifice

Semco No.
420

Round 1/8 orifice

Semco No.
440

Duckbill

Semco No.
8615

Duckbill

Semco No.
8648

Comb

Semco No.
8646

Durometer

Gloves, lightweight
lint-free white
cotton

Rex Model
1500 (or
equivalent)

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MAINTENANCE MANUAL

EQUIPMENT

Nylon bristle
brushes

Commercially available

Removing old sealant.

Pipe cleaners

Commercially available

Cleaning.

Funnel brushes

Commercially available

Cleaning.

3.

Definition of Sealing Terms
A.

The following definitions are included to provide a basic concept of the special terms used in sealing.
This list is not all inclusive but the more common terms are listed.
(1) Absolute Sealing - There can be no leakage allowed. All openings of any nature through the seal
plane are positively sealed. This is the first level of sealing. (All holes, slots, joggles, fasteners
and seams must be sealed.)
(2) Accelerator (Activator) - Curing agent for sealants.
(3) Application Time - The length of time sealant remains workable or suitable for application to
structure by brush, extrusion gun, spatula or roller.
(4) Base Compound - The major component of a two-part sealing compound which is mixed with the
accelerator prior to application to produce a fuel, temperature, pressure, weather and/or firewall
sealing material.
(5) Brush Coat - Apply an overcoating or continuous film of appropriate sealing compound by use
of a brush.
(6) Fay Seal or Faying Surface Seal - A seal barrier created by the sandwiching of sealant between
mating surfaces of structure. Special attention must be taken to avoid metal chips or dirt at the
faying surface.
(7) Fillet Seal - Sealant material applied at the seam, joint or fastener after the assembly has all
permanent fasteners installed and shall conform to the dimension in applicable figure.
(8) Hole - An opening that has no appreciable depth, such as a tool hole. Holes that penetrate the
seal plane must be metal filled with a fastener, gusset or patch.
(9) Injection Seal - Filling of channels by forcing sealant into a void or cavity after assembly.
(10) Integral Tank - Composition of structure and sealant material which forms a tank that is capable
of containing fuel without a bladder.
(11) Intermediate Seal - The second level of sealing. All holes, slots, joggles and seams in the seal
plane must be sealed. A minor amount of leakage is tolerable and permanent fasteners are not
required to be sealed.
(12) Post-Assembly Seal - A seal that is applied after the structure is assembled. (Fillet and injection
seals.)
(13) Preassembly Seal - Sealant material that must be applied during or prior to the assembly of the
structure. (Faying surface and pre-pack seals.)
(14) Pre-Pack Seal - A preassembly seal used to fill voids and cavities; can be a primary seal used
to provide seal continuity when used in conjunction with a fillet seal. It can be used as a backup
seal to support a fillet across a void. Fill the entire cavity to be pre- packed. Usage as a primary
seal should be kept to a minimum.
(15) Primary Seal - Sealant material that prevents leakage and forms a continuous seal plane. This
seal is in direct contact with the fuel, vapor, air, acid, etc. With few exceptions, it is in the form
of a fillet seal.
(16) Sealant - A compound applied to form a seal barrier.
(17) Seal Plane - A surface composed of structure, sealant and fasteners on which the continuity of
seal is established.
(18) Shank Sealing - Sealant compound shall be applied to the hole or to both the shank and the
underhead area of the fastener in sufficient quantity that the entire shank is coated and a small
continuous bead of sealant is extruded out around the complete periphery of each end of the
fastener when installed. The fastener shall be installed within the application time of the sealing
compound used.
(19) Squeeze-Out Life - Length of time sealant remains suitable for structure assembly in faying
surface seal application.

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(20) Tack-Free Time - Tack-free time is a stage, during the cure of the sealant compound, after which
the sealant compound is no longer tacky. When the sealant compound is pressed firmly with the
knuckles, but no longer adheres to the knuckles, the sealant compound is tack-free.
4.

Materials

A.

Type of Sealants - Sealants are categorized by type of usage. Type I sealants are separated into
classes to differentiate the materials according to method of application. Dash numbers following
the class designation indicate the minimum application time (in hours) for Class A and Class B, and
minimum work life (in hours) for Class C. Refer to Table 201 for application time, curing rate, etc., for
Type I sealants.
(1) Type I - Fuel, pressure, and weather sealant.
(a) Class A - Sealant which is suitable for brush application.
(b) Class B - Sealant which is suitable for application by extrusion gun, spatula, etc.
(c) Class C - Sealant which is suitable in faying surface applications.
(d) Quick Repair Sealant - This material is for use only in making repairs when an extremely
rapid curing sealant is required. A possible application includes sealing a leaking fuel tank
on an airplane which must be dispatched within a few hours.

CAUTION: QUICK REPAIR SEALANT MUST BE APPLIED WITHIN ITS
WORKING LIFE OF 15 MINUTES. ATTEMPTS TO WORK QUICK
REPAIR SEALANT BEYOND WORKING LIFE WILL RESULT IN
INCOMPLETE WETTING OF SURFACE AND WILL RESULT II\I
A FAILED SEAL.
(2) Type VIII - Low Adhesion Access Door Sealant. This Class B sealant is designed for sealing
faying surfaces where easy separation of the joined surfaces is required. The sealant has
low adhesion and forms a gasket that molds itself to fill all irregularities between two surfaces.
The sealant is exceptionally resistant to fuels, greases, water, most solvents and oils including
hydraulic oil.
NOTE:

Time periods presented below are based on a temperature of 77°F and 50 percent
relative humidity. Any increase in either temperature or relative humidity may shorten
these time periods and accelerate the sealant cure.

Table 201. Curing Properties of Type I Sealant
CLASS

APPLICATION
TIME (HOURS,
MINIMUM)

A-1/2

WORK LIFE
(HOURS,
MINIMUM)

TACK-FREE
TIME (HOURS,
MAXIMUM)

CURING RATE
(HOURS,
MAXIMUM)

1/2

10

40

A-2

2

40

72

B-1/2

1/2

4

6

B-2

2

40

72

B-4

4

48

90

C-24

8

24

96

168 (7 days)

C-48

12

48

120

336 (14 days)

C-80

8

80

120

504 (21 days)

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5.

General Requirements
A.

When working with sealants observe the following requirements.
(1) Unmixed sealants shall not be more than two months old when received. These sealants shall
not be more than six months old when used.
(2) Unmixed sealants stored at temperatures exceeding 80°F shall be used within five weeks.
(3) Sealants which have been premixed, degassed and flash frozen shall be maintained at -40°F or
lower and shall not be received more than two weeks beyond the date of mixing. These sealants
shall not be used more than six weeks after the date of mixing.
(4) Frozen sealant shall be thawed before being used. If sealant were applied at a temperature
below 60°F, it would not be sufficiently pliable for proper application and adhesion could be
critically reduced by condensation of moisture. On the other hand, although sealant must
extrude freely for proper application, it would be subject to excessive slumping if applied at a
temperature above 80°F. Frozen sealant may be thawed by any s uitable means which does
not cause contamination or overheating of the sealant and does not shorten the application
time of the sealant to an impractical period. Examples: Thawing by exposure to ambient air
temperature, accelerated thawing by exposure in a constant temperature bath (using clean, hot
water), accelerated thawing in a microwave oven. In any case, thawing temperature and time
shall be adjusted to give a thawed sealant temperature between 60°F, and 80°F at the time the
sealant is applied.
(5) Mixed, frozen sealants which have thawed shall not be refrozen.
(6) Complete preassembly operations such as fitting, filing, drilling, countersinking, dimpling and
deburring prior to cleaning and sealant application.
(7) Surfaces must be clean and dry, free from dust, lint, grease, chips, oil condensation or other
moisture and all other contaminating substances prior to the application of sealant.
(a) All exposed bonding primer or bonded assemblies which are to be sealed shall be cleaned
using Scotch Brite followed by solvent cleaning using Trichloroethane.
NOTE:

Bond primer shall not be removed; just lightly scuffed with Scotch Brite.

(8) Sealant materials may be applied to unprimed or primed surfaces. Nonchromated or epoxy
primers shall have good adhesion to the substrate material and shall have aged at least 48
hours prior to sealant application. Adhesive bonding primer shall be scotchbrited and cleaned
before applying sealant.
(9) Sealants shall not be applied when the temperature of either the sealant or the structure is below
60°F.
(10) Sealant applied by the fillet or brush coat methods shall always be applied to the pressure side
of a Joint if possible.
(11) After application, sealants shall be free of entrapped air bubbles and shall not exhibit poor
adhesion. All fillets shall be smoothed down and pressed into the seam or joint with a filleting
tool before the sealant application time has expired.
(12) Where fasteners have been shank or underhead sealed, extruded sealant shall be evident
around the complete periphery of the fastener to indicate adequate sealing. Sealant extruded
through a hole by a rivet shall be wiped from the end of the rivet before bucking. Threaded
fasteners which have been shank or underhead sealed shall not be retorqued after the
expiration of the application time of the sealant. Prior to torqueing, sealant shall be removed
from the threads. In torqueing, turn the nut rather than the bolt, if possible.
(13) Pressure testing shall not be accomplished until the sealant is cured.
(14) Sealant shall not be applied over ink, pencil or wax pencil marks. If these materials extend into
the sealing area, they must be removed.
(15) If sealing is to be accomplished over primer and the primer is removed during the cleaning
process, it is permissible to seal directly over the cleaned area and then touch up the exposed
areas after the sealant has been applied and is tack free.
(16) Sealed structure shall not be handled or moved until sealant is tack free (sealant may be
dislodged or have the adhesion damaged). Excessive vibration of structure, such as riveting,
engine run up, etc. is not permitted.

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(17) Drilling holes and installing fasteners through a fay sealed area shall be performed during the
working life of the faying sealant or the entire shank and area under fastener head shall be fay
sealed.
6.

Sealant Curing
A.

Room Temperature.
(1)
(2)
(3)

B.

7.

Room temperature curing properties are based on a temperature of 77°F, +5°F or -5°F and a
relative humidity of 50 percent unless otherwise indicated.
Room temperature curing properties of Type I sealants are given in Table 201.
Curing properties of Type VIII, Class B sealants are the same as for Type I, Class B. Adhesion
to aluminum should be (peel) less than two pounds per inch width.

Accelerated Curing.
(1) Accelerated curing of sealant can be accomplished in several ways. The procedure to be used
is dependent on the type of sealant and other factors.
(2) The cure of Type I sealants can be accelerated by an increase in temperature and/or relative
humidity. Warm circulating air at a temperature not to exceed 140°F may be used to accelerate
cure. Heat lamps may be used if the surface temperature of the sealant does not exceed 140°F.
At temperatures above 120°F, the relative humidity will normally be so low (below 40 percent)
that sealant curing will be retarded. If necessary, the relative humidity may be increased by the
use of water containing less than 100 parts per million total solids and less than 10 parts per
million chlorides.

Mixing of Sealants
A.

Requirements.
(1) Sealants shall be mixed or thinned in accordance with the manufacturer's recommendations and
thoroughly blended prior to application. All mixed sealant shall be as void free as possible.
(2) Prior to mixing, the sealing compound base and its curing agent, both in their respective original
unopened containers, shall be brought to a temperature between 75°F and 90°F along with all
required mixing equipment.

B.

Hand Mixing of Sealant.
(1) Weigh into clean, wax-free containers the correct amount of base and curing agent, per
manufacturer's instructions, immediately prior to mixing. An alternate method is to mix the
sealant on a flat plate with a spatula. The scales and weighing process must be controlled
within +2 or -2 percent to ensure good quality.
(2) Do not allow the accelerator to come into contact with the sides of the container.
(3) Materials shall be accurately weighed on scales that are calibrated and maintained for required
accuracy.
(4) Mix the components until the color is uniform taking care not to trap air in the sealant.
(5) Transfer the sealant to another clean container and complete the mix.

C.

Sem-Kit Mixing.

WARNING: T-IE CARTRIDGE SHOULD BE HELD FIRMLY, BUT MUST NOT
BE SQUEEZED, AS THE DASHER BLADES MAY PENETRATE
THE CARTRIDGE AND INJURE THE HAND.
(1)
(2)

Pull dasher rod to the FULL OUT position so that the dasher is at the nozzle end of the cartridge.
Insert ramrod in the center of the dasher rod against the piston and push the piston in
approximately one inch.
NOTE:

Extra force will be needed on the ramrod at the beginning of accelerator injection into
the base material.

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(3) Move the dasher rod in approximately one inch, then push piston in another inch. Repeat this
action until accelerator is distributed along the entire length of the cartridge.
NOTE:

The accelerator has been fully injected into the cartridge when the ramrod is fully
inserted into the dasher rod.

(4) Remove and properly discard the ramrod.
NOTE:

Mixing the accelerator and base material can be accomplished manually, or as an
alternate method, with the use of a drill motor.

(5) Manual Mixing.
(a) Begin mixing operation by rotating the dasher rod in a clockwise direction while slowly
moving it to the FULL OUT position.
NOTE:

Do not rotate the dasher rod counterclockwise; the four-blade dasher inside the
cartridge will unscrew and separate from the dasher rod.

(b) Continue clockwise rotation and slowly move the dasher rod to the FULL IN position.
A minimum of five full clockwise revolutions must be made for each full-out stroke and
1
for each full-in stroke of the dasher rod. Approximately sixty strokes are necessary
for a complete mix.
NOTE:

If streaks are present in the sealant (viewing through the side of the
cartridge), the sealant is not completely mixed.

End mixing operation with the four-blade dasher at the bottom of the cartridge.
Hold cartridge upright; unscrew dasher rod from the four-blade dasher by gripping the
cartridge at the four-blade dasher and turn the dasher rod counterclockwise. Remove
dasher rod.
(e) Screw appropriate nozzle into the cartridge. If sealant gun is to be used, install cartridge
in gun.
(6) Drill motor mixing.
(c)
(d)

NOTE:
(a)

A tapered rotary file or a 25/64 inch drill bit may be used with a drill motor to turn the
dasher rod.

Insert the rotary file/drill bit into the dasher rod approximately 1/2 inch.

WARNING: THE CARTRIDGE SHOULD BE HELD FIRMLY, BUT NOT
SQUEEZED, AS THE DASHER BLADES MAY PENETRATE
THE CARTRIDGE AND INJURE THE HAND.
(b) Verify the drill motor will rotate the dasher rod clockwise (looking toward the nozzle end of
the cartridge).
(c) With the cartridge held firmly in one hand and the drill motor in the other, rotate the dasher
rod at approximately 50 revolutions-per- minute while moving the dasher rod to FULL IN
and FULL OUT positions.
Mix sealant for at least 50 strokes (a stroke is one complete full-in and full-out stroke
1
of the dasher rod).
NOTE:
(d)

If streaks are present in the sealant (viewing through the side of the
cartridge), the sealant is not completely mixed.

End mixing operation with the four-blade dasher at the bottom of the cartridge.

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(e) Hold cartridge upright; remove drill motor and rotary file/drill bit from the dasher rod;
unscrew dasher rod from the four- blade dasher by gripping the cartridge at the four-blade
dasher and turn the dasher rod counterclockwise. Remove dasher rod.
(f) Screw appropriate nozzle into the cartridge. If sealant gun is to be used, install cartridge
in gun.
8.

Cleaning
A.

All surfaces to which sealant is to be applied shall be clean and dry.

B.

Remove all dust, lint, chips, shavings, etc. with a vacuum cleaner where necessary.

C.

Cleaning shall be accomplished by scrubbing the surface with clean cheesecloth moistened with
solvent. The cloth shall not be saturated to the point where dripping will occur. For channels and
joggles, pipe cleaners and/or funnel brushes may be used instead of cheesecloth.
(1) The solvents to be used for the cleaning in the integral fuel tank are A-A-59281 or TT-M-261
for the first or preliminary cleaning. For the final cleaning, O-T-620, 1, 1, 1 - Trichloroethane,
Technical, Inhibited only must be used.

D.

The cleaning solvent should never be poured or sprayed on the structure.

E.

The cleaning solvent shall be wiped from the surfaces before evaporation using a piece of clean, dry
cheesecloth in order that oils, grease, wax etc. will not be redeposited.

F.

It is essential that only clean cheesecloth and clean solvent be used in the cleaning operations.
Solvents shall be kept in safety containers and shall be poured onto the cheesecloth. The cheesecloth
shall not be dipped into the solvent containers and contaminated solvents shall not be returned to the
clean solvent containers.

G.

Final cleaning shall be accomplished immediately prior to sealant application by the person who is
going to apply the sealant.
(1) The area which is to be sealed shall be thoroughly cleaned. A small clean paint brush may be
needed to clean corners, gaps, etc. Always clean an area larger than the area where the sealant
is to be applied. Never clean an area larger than 30 inches in length when practical. When the
area is being scrubbed with a moistened cloth in one hand, another clean dry cloth shall be held
in the other hand and shall be used to dry the structure. The solvent must be wiped from the
surfaces before it evaporates.
(2) The above procedure shall be repeated until there is no discoloration on the clean drying cloth.
Marks resulting from wax or grease pencils must be removed from parts prior to sealing.
Allow all cleaned surfaces to dry a minimum of 5 minutes before the application of sealant materials.

H.

9.

I.

Sealant shall be applied as soon as possible after cleaning and drying the surfaces to be sealed.
Do not handle the parts between the cleaning and sealing operations. Sealant application personnel
handling cleaned surfaces shall wear clean white gloves to prevent surface contamination. In the
event contamination does occur, the surfaces shall be recleaned.

J.

Safety precautions should be observed during the cleaning and sealing operation. Cleaning solvents
are toxic and flammable in most cases. Fresh air masks and/or adequate ventilation are required for
all closed areas. The structure shall be electrically grounded before starting any cleaning or sealing
operation.

Sealing Application
A.

General.
(1) All new sealing shall be accomplished using the type of sealing material required for the area
being sealed. All sealant repairs shall be accomplished using the same type of sealing material
as that which is being repaired.
(2) Application time of the sealing compound shall be strictly observed. Material which becomes
too stiff and difficult to work or which does not wet the surface properly shall be discarded even
though the application time has not expired.
(3) For an illustration of the integral fuel bay and sealing techniques, refer to Figure 201.
(4) Prior to sealant application, all surfaces to be sealed shall be cleaned per paragraph 8.

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B1738

INSPECTION
COVER
(TYPICAL)

R TRAILING
SKIN

UPP

SKIN

Ir Ii

D AU/

NG EDGE
;TIFFENER

0526T 1010
0526T1009
0526T1011

Integral Fuel Bay Sealing
Figure 201 (Sheet 1)

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B1739

FAYING SURFACE SEAL

TYPICAL RIB
SECTION

FAY SEAL
(SEALANT
EXTRUDED

SEALANT EXTRUDED
CONTINUOUSLY

,/
"'

NOTE:

I

CONTINUOUSLY)

_·M

METHODS
THE FOLLOWING EXAMPLES SHOW TYPICAL CROSS SECTIONS OF SEALING
SKIN AND RIB
AND TECHNIQUES USED IN THE FUEL BAY AREA. IN MOST CASES, MGX
THICKNESS COMBINED IS APPROXIMATELY 0.070 INCH. MINIMUM SEALANT
APPLICATION AT ANY POINT SHOULD NOT BE LESS THAN 0.060 INCH.
5598T2007
5598T2007

Integral Fuel Bay Sealing
Figure 201 (Sheet 2)

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B1740

IJ

J/

.^^'-

I

*

T'.

I

,"d

\

",

.3

/

S

\'N
I&

'A1

?S^
I

I
5598T1010
6280T1003

Integral Fuel Bay Sealing
Figure 201 (Sheet 3)

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B1741

S

5598T1009

Integral Fuel Bay Sealing
Figure 201 (Sheet 4)

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B.

Faying Surface Sealing - The application of a faying surface seal shall be made only when new
structure is being added to the airplane and requires a faying surface seal or when the structure
and/or parts have been disassembled for reasons other than a faulty seal. Fay sealed joints must be
closed and fastened before expiration of the work life given in Table 201. Excess sealant must squeeze
out of a fay sealed joint when attachment is made. Countersinking and reaming of holes through a
fay sealed joint is permissible when every other hole is held firm by temporary or permanent holding
fasteners. Spring loaded plunger type clecos are inadequate to create sufficient pressure for sealant
squeeze-out. Fabrication and changes done after sealing are not recommended and shall be held to
a minimum. Fasteners installed after the sealant has cured to replace temporary fasteners shall be
installed wet with sealing compound.
NOTE:

Pre- assembly operations such as fitting, filing, drilling, dimpling and deburring shall be
completed prior to cleaning and sealing application.

(1) Immediately prior to final closure of the joint, sealant shall be applied to one mating surface of the
joint with a sealant gun, spatula, roller or other suitable tool. Sufficient sealant shall be applied
so that the space between the assembled faying surfaces is completely filled with sealant and
a small excess is squeezed out in a continuous bead around the periphery of the joint when the
joint is secured (refer to Figure 201, Sheet 2 ).
(2) Place parts in assembly position and install the fasteners within the application time of the
faying surface sealant. When assembly with permanent type fasteners is not feasible, temporary
fasteners (clecos or bolts) may be used, but when the temporary fasteners are used, they must
be replaced by permanent type fasteners prior to the expiration of the work life of the faying
surface sealant. Removal of each individual temporary fastener shall be followed immediately
by the installation of the permanent fastener.
(3) When a fillet seal is required around the periphery of a fay sealed joint, it is not necessary to
remove the sealant squeeze out where the fillet is to be applied, provided that the material
which was squeezed out has been shaped into a small fillet configuration prior to the expiration
of the application time. When the squeeze-out has been shaped, a final or full bodied seal
can be applied over the shaped squeeze-out without waiting for the squeeze-out to cure. If the
squeezed out material was not shaped before the expiration of its application time, it shall be
cured to a tack-free condition and then removed, by use of a plastic tool, from locations where
a fillet is to be applied.
(4) Immediately after the assembly is completed and all permanent type fasteners have been
installed, remove uncured sealant which extrudes onto the exterior of the airplane using clean
rags moistened with A-A-59107, Toluene or TT-M-261, Methyl- Ethyl-Ketone.
C.

Injection Sealing.
(1) Sealant shall be injected into the channel, joggle, void or cavity from one point only, using a
sealant gun, in such a manner that no air is entrapped and the channel, joggle, void or cavity is
completely filled and sealant is observed emerging from the prescribed opening (refer to Figure
201, Sheet 4). If multiple exits or channels exist, block each channel exit after it is filled, without
stopping the injection, so that sealant extrudes into all necessary channels.
(2) Remove excess sealant before the expiration of its application time and smooth flush with the
surface using a suitable tool.

D.

Fillet Sealing.
(1) Fastener considerations:
(a) Do not fillet seal any parts until they are held completely together by permanent fasteners.
(b) Prior to filleting the periphery of bolted structure and fittings, it is necessary that all bolts,
accomplishing the attachment, be properly torqued.
(2) The sealant shall be applied using a sealant gun or spatula.
(3) When using a sealant gun for fillet sealing, the nozzle tip shall be pointed into the seam or joint
and shall be maintained nearly perpendicular to the line of travel. A continuous bead of sealant
shall precede the tip and the tip size, shape and rate of travel shall be such that sufficient sealant
shall be applied to produce the required fillet.
(4) Fillets shall be shaped or formed to meet the size and shape requirements as shown in applicable
figures using the nozzle tip and/or fairing tools to press against the sealant while moving parallel
to the bead. Exercise caution to prevent folds and entrapment of air during application and

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(5)

(6)
(7)
(8)
(9)
(10)

(11)
(12)

10.

shaping of the fillet and work out any visible air bubbles. The fillet shall be formed so that the
highest portion of the fillet is centered over the edge of the structure or fitting. Lubrication in
any form shall not be used for smoothing purposes. In all cases, fillet size shall be kept as near
minimum as practical.
Where it is more convenient or fillet slumping is encountered, the fillet may be applied in two
stages. A small first fillet should be applied which is allowed to cure to a tack-free state, followed
by a second application of sealant sufficient to form the final fillet conforming to the specified
dimensions for a fillet seal. If the first fillet has cured, it must be cleaned before the second
application of sealant is made. If the fillet has only cured to a tack-free state, it shall be wiped
lightly with a gauze pad or cheesecloth pad dampened with cleaning solvent.
Allow the sealant to cure to a tack-free condition prior to the airplane being moved, handled
and/or worked on.
In cases where a fillet seal connects to an injection seal, the full bodied fillet shall extend past
the end of the injection and then taper out.
Lap joint and seam fillets shall be as shown in Figure 201, Sheet 3.
Butt joint fillets shall be as shown in Figure 201, Sheet 3.
Bolts shall be fillet sealed as shown in Figure 201, Sheet 3. The area for sealing shall consist of
the area of the structure surrounding the base of the fastener end plus the entire exposed area of
the fastener. An optional method of sealing threaded fasteners is to apply a brush coat of Type
I, Class A sealant. Where brush coating is used as the method of sealing threaded fasteners,
the sealant must be worked around each fastener with a stiff brush and considerable care to be
effective. A simple pass of the brush with the sealant is not sufficient to produce an effective
seal.
Dome-type nutplates shall be fillet sealed as shown in Figure 201, Sheet 3. The area for sealing
shall consist of the area of the structure surrounding the base of the fastener and from there up
over the rivets to the dome.
Hole filling and slot fillets shall be as shown in Figure 201, Sheet 3.
(a) Tooling holes shall be plugged with a shank sealed soft rivet and then brush coated with
Type I, Class A sealant.

Sealant Repair
A. Materials - Repairs, in general, shall be accomplished with the same type of material as that being
repaired.

B.

NOTE:

Type I, Class B-1/2 is recommended for use during cold weather to obtain an accelerated
cure.

NOTE:

Type I, Quick Repair sealant may be used as a repair for sealant in pressure vessels and
fuel tanks if desired for fast cure and rapid dispatch.

Temperature Requirements.
(1) The structure shall be above 60°F before the sealant is ap plied and shall remain above 60°F
until the sealant is tack-free.
NOTE:

For outside operations only, the temperature of the structure may be allowed to drop
below 60°F but not below 58°F, after application for a period of time not to exceed 48
hours; however, the structure must be subsequently heated to above 60°F and the
sealant allowed to become tack-free before the tanks are refueled.

(2) The maximum air temperature allowed to come in contact with the curing sealant is 120°F.
C.

Fillet and Fastener Sealing Repairs.
(1) Repair of damaged or faulty sealant applications shall be accomplished as follows:
(a) Remove all damaged or faulty sealant to ensure solid residual material.
(b) Sealant shall be cut so as to produce a smooth continuous scarfed face. The sealant shall
be completely removed in the affected areas. The cutting tools should only be made from
nonmetallic materials that are softer than aluminum.

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(c)

Inspect repair areas for clean and smooth cuts. Loose chunks or flaps of sealant on the
cut areas shall be removed.
(d) Clean the area to be sealed, including the scarfed face of the old seal, per paragraph 8.
(e) Apply new fillet seals. Slight overlapping of the fresh material over the existing fillet is
permissible. A large buildup of sealant shall not be allowed.
(f) Rework of a fillet which has been oversprayed or brushed with primer shall be
accomplished by a scarfed joint and removal of the fillet having primer on it, in the area of
the repair. The primer shall not be sandwiched between the old and new sealants.
(g) If the primer is removed during the cleaning operation, it is permissible to apply the new
fillet seal directly over the clean bare metal and then touch up with the proper primer all
exposed areas of bare metal after the sealant has been applied.
D.

Faying Surface Sealing Repair - After determining the area which contains the faulty and/or leaking
faying surface seal, the repair shall be accomplished by applying a fillet seal along the edge of the
part adjacent to the faying surface seal long enough to fully cover the area of the faulty and/or leaking
seal.

E.

Brush Coat Sealing Repair - Repair of damaged or leaking brush coat seals shall be accomplished by
removing the discrepant brush coat. Clean the area of sealant removal and the surrounding structure
and sealant per paragraph 8. Apply a new brush coat of sealant.

F.

Integral Fuel Tank Sealing Using PR-1826 Class B Rapid Curing Sealant.
(1) Remove damaged section of sealant with a sharp plexiglass scraper. Taper all cuts in old sealant
at 45 degree angles.
(2) Thoroughly clean with solvent and abrade old areas which are to be over coated. Clean one
small area at a time, then dry with a clean cloth before the solvent evaporates.
NOTE:

Always pour solvent on the cloth to maintain a clean solvent supply.

NOTE:

In fuel tanks which have been in operation, the sealant will be soaked and should be
dried in area of the repair with a vapor- proof heat lamp or hot air blower before new
sealant is applied.

(3) After the surface has been cleaned and dried, apply a heavy layer of PR-1826 Adhesion
Promoter with a clean brush or gauze pad. Allow adhesion promoter a minimum of 30 minutes
to dry.
NOTE:

Care must be taken to obtain a uniform thin coat of adhesion promoter. Thin enough
to cover the surface, but not heavy enough to run.

(4) Mix PR-1826 Class B sealant according to instructions supplied with the material.
(5) Apply PR-1826 Class B sealant, 1/8 to 3/16 of an inch thick, to the repair area with a spatula or
paddle shaped tool. Firmly press sealant in place and form to desired shape. Overlap PR-1826
Class B sealant over old sealant from 1/8 to 1/4 of an inch.
NOTE:

Sealant may be applied up to 8 hours after the application of adhesion promoter. After
8 hours, the surface should be recleaned and adhesion promoter reapplied.

(6) Allow sealant to cure a minimum of 2 hours at 77° F before re fueling. Curing time is solely
based on temperature and will be halved for every 18°F increa se, and doubled for every 18°F
decrease from the standard 77° F.

11.

Classification of Fuel Leaks
A.

Fuel leaks are classified into one of four categories based on the observed size of the leaks.
Dependent on where the leak is located, immediate corrective action may be required prior to flight.
Leaks may be classified as follows and are illustrated in Figure 202:
(1) Stains - An area of 0.75 inch or less in diameter.
(2) Seep - An area from 0.75 inch to 1.50 inch in diameter.
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MODEL 172

MAINTENANCE MANUAL

B1742

HEAVY
SEEP

SEEP

0.75 TO
1.50 INCH
1.50 TO
4.00 INCHES

I
I

4 0
STAIN
0.75 INCH
MAXIMUM
RUNNING
LEAK

SIZE WILL VARY
WITH LOCATION
AND INTENSITY
OF LEAK.

FUEL WILL USUALLY
FLOW IN THIS AREA
ALONG SKIN CONTOUR
AFTER IT IS WIPED DRY.

FUEL USUALLY DRIPS
AT THIS POINT.

0516T1006

Classification of Fuel Leaks
Figure 202 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B.

(3) Heavy Seep - An area from 1.50 inch to 4.00 inch in diameter.
(4) Running Leak -- Size varies with location and intensity of leak.
The following leaks require corrective action before further flight:
(1) Running leaks in any area.
(2) Stains, seeps or heavy seeps in an enclosed area.
An enclosed area is defined as the wing leading edge and the section of wing inboard
or outboard of the fuel bays.
The following leaks require correction when the airplane is grounded for other maintenance:
(1) Stains, seeps or heavy seeps not in an enclosed area.
NOTE:

C.

12. Sealing Fuel Leaks
A.

B.

13.

Determine Source of Leak.
(1) Fuel can flow along a seam or structure of the wing for several inches, making the leak source
difficult to find. A stained area is an indication of the leak source.
(2) Fuel leaks can be found by testing the complete bay as described in Testing Integral Fuel Bay.
(3) Another method of detecting the source of a fuel leak is to remove access doors and blow with
an air nozzle from the inside of the bay in the area of the leak while soap bubble solution is
applied to the outside wing skin.
Repair Leak.
(1) Remove existing sealant in the area of the leak.
(2) Clean the area and apply a filet seal. Press sealant into leaking area with a small paddle, working
out all air bubbles.
(3) If leakage occurs around a rivet or bolt, replace the rivet or loosen bolt, retorque and reseal
around nutplate.
(4) Apply Type VIII sealant to access doors, fuel quantity transmitter, etc., as required and reinstall
to structure.
(5) Allow sealant to completely cure.
(6) Test fuel bay for leakage. Refer to Testing Integral Fuel Bay.

Testing Integral Fuel Bay
A. The fuel system consists of two vented, integral fuel tanks (one in each wing). The following procedure
should be used only after sealant has fully cured.
(1) Remove vent line from vent fitting and cap fitting.
(2) Disconnect fuel lines from bay.
(3) To one of the bay fittings, attach a water manometer capable of measuring 20 inches of water.
(4) To the other bay fitting, connect a well-regulated supply of air (0.5 PSI maximum, or 13.8 inches
of water). Nitrogen may be used where the bay might be exposed to temperature changes while
testing.
(5) Make sure filler cap is installed and sealed.
(6) Apply pressure slowly until 0.5 PSI is obtained.
(7) Apply a soap solution as required.
(8) Allow 15 to 30 minutes for pressure to stabilize.
(9) If bay holds for 15 minutes without pressure loss, seal is is acceptable.
(10) Reseal and retest if any leaks are found.

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CHAPTER

INDICATING/
RECORDING
SYSTEMS

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

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DATE

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31 - LIST OF EFFECTIVE PAGES
© Cessna Aircraft Company

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Number

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By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
INDICATING/RECORDING SYSTEMS - GENERAL .................................
Scope......................................................................
Definition...................................................................
INSTRUMENT AND CONTROL PANELS - MAINTENANCE PRACTICES.............
Description and Operation ...................................................
Panel Removal and Installation...............................................
INSTRUMENT AND CONTROL PANELS - MAINTENANCE PRACTICES Airplanes with
Garmin G1000...................................................................
General ....................................................................
Center Panel Removal/Installation............................................
Switch Panel Removal/Installation .........
...........
....................
Throttle/Flap Panel..........................
................................
Instrument Panel Removal/Installation ........................................
DIGITAL CLOCK - MAINTENANCE PRACTICES ...................................
Description and Operation ...................................................

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HOUR METER - MAINTENANCE PRACTICES.....................................
Description and Operation ...................................................
Hour Meter Removal/Installation
.............................. ........

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ANNUNCIATOR PANEL - MAINTENANCE PRACTICES ............................

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Description and Operation ...................................................
Annunciator Panel Removal/Installation .......................................

© Cessna Aircraft Company

31 - CONTENTS

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
INDICATING/RECORDING SYSTEMS - GENERAL
1.

Scope
A.

2.

This chapter contains information on those systems and components used to indicate and/or record
various parameters of the engine, airframe or related flight operations. Also included in this chapter
is information on the instrument panels that house the indicating/recording systems.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The section on instrument and control panels provides general removal and installation
instructions for the various panels used in the cockpit.
(2) The section on indicating provides information on the digital clock.
(3) The section on recording provides information on the hour meter.
(4) The section on annunciation provides information on the multi-system panel annunciator.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
INSTRUMENT AND CONTROL PANELS - MAINTENANCE PRACTICES
1.

Description and Operation
A.

The instrument panel is divided into sections to facilitate easy removal and installation of particular
components without removing the entire panel.
(1) The pilot side of the instrument panel is broken up into three separate panels, with the flight
instruments grouped in a panel, the avionics dials and tachometer located in a panel, and the
indicating/recording instruments grouped in a third panel.
(2) The switch panel is located below the pilot side instrument panel and houses the majority of
switches and circuit breakers in a single location.
(3) The copilot side of the instrument panel houses the Hobbs meter and remote ELT activation
switch, and is designed to allow for panel expansion.
NOTE:

2.

For an overview of the various sub panels which make up the instrument panel, refer
to Figure 201.

Panel Removal and Installation
A.

The individual panels may be removed by unscrewing the perimeter screws located on each panel.
The flight instrument sub-panel has been designed to be moved aft without disconnecting the electrical
or mechanical connections to that panel.

B.

If entire panels are being removed, it may be necessary to disconnect various electrical and/or
mechanical connections prior to removing the panel.

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MODEL 172
MAINTENANCE MANUAL

B1743

PILOT'S

ENGINE

OUTBOARD
PANEL

PILOT'S

CENTER
PANEL

PILOT'S
INBOARD
PANEL

/

COPILOT'S
PANEL

RADIO
PANEL

.6

/

of

0

«*

JC
.

0

a

>.o

I

R@.

a

SWITCH AND
CIRCUIT BREAKER
PANEL

ENGINE
CONTROLS

.

a

I

0

r-~L

HEATING AND
VENTILATING
CONTROLS

0585T1040

Instrument Panels
Figure 201 (Sheet 1)

31-'10-00
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

INSTRUMENT AND CONTROL PANELS - MAINTENANCE PRACTICES
Airplanes with Garmin G1000
1.

General
A.

2.

3.

4.

5.

This section gives removal and installation procedures for the center panel, switch panel, throttle/flap
panel, and instrument panel.

Center Panel Removal/Installation
A.

Remove the Center Panel (Refer to Figure 201).
(1) Make sure the MASTER and AVIONICS switches are in the off position.
(2) Remove the screws that attach the center panel to the instrument panel.
(3) Carefully pull out the center panel as necessary to get access behind the panel.
(4) Put labels on the electrical connectors and hoses and disconnect them from the instruments.

B.

Install the Center Panel (Refer to Figure 201).
(1) Connect the electrical connectors and hoses to the applicable instruments.
(2) Remove the labels from the electrical connectors and hoses.
(3) Carefully put the center panel in the instrument panel.
(4) Install the screws that attach the center panel.

Switch Panel Removal/Installation
A.

Remove the Switch Panel (Refer to Figure 201).
(1) Make sure the MASTER and AVIONICS switches are in the off position.
(2) Remove the screws that attach the switch panel to the instrument panel.
(3) Carefully pull the switch panel out from the instrument panel to get access behind the panel.
(4) Disconnect the switches from the electrical connections.

B.

Install the Switch Panel (Refer to Figure 201).
(1) Connect the electrical connections to the switches.
(2) Put the switch panel in the instrument panel.
(3) Attach the switch panel with the screws.

Throttle/Flap Panel
A.

Throttle/Flap Panel Removal (Refer to Figure 201).
(1) Disconnect the negative cable from airplane battery. Refer to Chapter 24, Battery - Maintenance
Practices.
(2) Make sure the MASTER ALT/BAT and AVIONICS switches are in the off position.
(3) Remove the screws that attach the throttle/flap panel to the instrument panel.
(4) Carefully pull the throttle/flap panel out from the instrument panel to get access behind the panel.
(5) Disconnect the switches from the electrical connections.

B.

Throttle/Flap Panel Installation (Refer to Figure 201).
(1) Connect the electrical connections to the switches.
Put the throttle/flap panel in the instrument panel.
(2)
(3) Attach the throttle/flap panel with the screws.
(4) Connect the negative battery cable. Refer to Chapter 24, Battery - Maintenance Practices.

Instrument Panel Removal/Installation
A.

Remove the Instrument Panel (Refer to Figure 201).
(1) Disconnect electrical power to the airplane.
(a) Make sure the AVIONICS switch is in the off position.
(b)
Disengage the two PFD circuit breakers, the MFD, STDBY BATT, STDBY IND-LTS AUDIO
circuit breakers.
Remove the center panel. Refer to Center Panel - Removal/Installation.
(2)
(3) Remove the switch panel. Refer to Switch Panel - Removal/Installation.
(4) Remove the Audio Panel. Refer to Audio Panel - Maintenance Practices.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

INSTRUMENT
PANEL

SWITCH
PANEL

/

00

CIRCUIT
BREAKER
PANEL

CENTER
PANEL

THROTTLE/
FLAP
PANEL

DETAIL A
AIRPLANES WITH GARMIN G1000

0510T1007
A051T1 109

Instrument and Control Panel Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
(5) Remove the screws that attach the control column collars to the instrument panel.
(6) Remove the hourmeter.
(a) Remove the screws for the hourmeter.
(b) Pull the hourmeter out and disconnect the connector.
(7) Remove the Control Display Units (CDU). Refer to Control Display Unit (CDU) - Maintenance
Practices.
(8) Remove the screws from the instrument panel.
(9) Disconnect and remove the ELT switch from the instrument panel.
NOTE:

The ELT switch can only be removed from the back of the instrument panel.

(10) Remove the instrument panel.
B.

Install the Instrument Panel (Refer to Figure 201).
(1) Put the instrument panel in position.
(2) Install the ELT switch and connect the electrical connector.
(3) Install the instrument panel screws.
(a) Make sure to put the electrical connector for the hourmeter through the panel hole for the
hourmeter installation.
(4) Connect the electrical connector to the hourmeter.
(5) Install the hourmeter.
(6) Attach the collar for the control column to the instrument panel.
(7) Put the switch panel in position and connect the electrical connections to the switches.
(8) Install the switch panel to the instrument panel with the screws.
(9) Put the center panel in position and connect the electrical connectors and vacuum hoses to the
instruments.
(10) Install the center panel to the instrument panel with the screws.
(11) Install the Control Display Units (CDU). Refer to Control Display Unit (CDU) - Maintenance
Practices.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
DIGITAL CLOCK - MAINTENANCE PRACTICES
1.

Description and Operation
A.

The digital clock is located in upper left side of the instrument panel and incorporates clock,
temperature and voltage readings in a single unit. For removal/installation of the OAT/Clock, refer to
Chapter 34, Outside Air Temperature Gauge - Maintenance Practices.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
HOUR METER - MAINTENANCE PRACTICES

1.

2.

Description and Operation
A.

The hour (Hobbs) meter is located in the upper right corner of the instrument panel and provides
indication of flight hours based on engine operation.

B.

The hour meter receives power through the WARN circuit breaker located on the lower instrument
panel. The hour meter is grounded through the Oil Pressure Switch, and anytime oil pressure exceeds
20 PSI a ground is sent from the switch to the hour meter, completing a circuit and activating the hour
meter.

Hour Meter Removal/Installation
A.

Remove Hour Meter (Refer to Figure 201).
(1) Gain access to backside of instrument panel and hold nuts while loosening screws.
(2) Disconnect electrical connectors leading into hour meter.

B.

Install Hour Meter (Refer to Figure 201).
(1) Connect electrical connectors to hour meter.
(2) Install hour meter to panel and secure using screws and nuts.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1745

II

HOUR METER
NUT

INSTRUMENT
PANEL
SCREW

DETAIL A

0585T1040
A0518T1020

Hour Meter Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL -172
MAINTENANCE MANUAL
ANNUNCIATOR PANEL - MAINTENANCE PRACTICES
1.

Description and Operation
A.

The annunciator panel is a multi-system display which provides visual warning and caution information
related to various systems and fuel levels throughout the airplane. The annunciator presents this
visual information in either amber (caution) or red (warning) messages. Refer to Table 201 for a
breakdown of messages and their inputs.

B.

Table 201 is provided to give a basic overview of the annunciator system and its inputs. This table
should be used in conjunction with the Wiring Diagram Manual to aid in system troubleshooting.

Table 201. Annunciator Panel Messages and Inputs
MESSAGE

COLOR

MEANING

SOURCE OF SIGNAL

L LOW FUEL

Amber

Low fuel condition detected in
the left tank.

Left fuel quantity system.

LOW FUEL R

Amber

Low fuel condition detected in
the right tank.

Right fuel quantity
system.

L LOW FUEL R

Amber

Low fuel condition detected
in both the left and right fuel
tanks.

Left and right fuel quantity
systems.

L LOW FUEL and
left fuel gauge
needle parked
below 0

Amber

Short, open or increasing
resistance over time.

Left fuel transmitter or
electrical line between
transmitter and fuel
gauge.

LOW FUEL R and
right fuel gauge
needle parked
below 0

Amber

Short, open or increasing
resistance over time.

Right fuel transmitter or
electrical line between
transmitter and fuel
gauge.

L LOW FUEL
R and both fuel
gauge needles
parked below 0

Amber

Short, open or increasing
resistance over time.

Left and right transmitters
or electrical lines
between transmitters
and fuel gauge.

OIL PRESS

Red

Oil pressure less than 20 PSI.

Oil pressure switch
(SN001) supplying
ground to annunciator.

L VAC

Amber

Vacuum less than 3.0 In.Hg.

Left vacuum switch
(SN012) supplying
ground to annunciator.

VAC R

Amber

Vacuum less than 3.0 In.Hg.

Right vacuum switch
(SN011) supplying
ground to annunciator.

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MAINTENANCE MANUAL
Table 201. Annunciator Panel Messages and Inputs (continued)
MESSAGE
COLOR
MEANING

SOURCE OF SIGNAL

LVAC R

Amber

Vacuum less than 3.0 In.Hg.

Right vacuum switch
and left vacuum switch
supplying ground to
annunciator.

VOLTS

Red

Voltage less than 24.5 VDC,
+0.35 or -0.35 VDC.

Ground from the
alternator control unit
to the annunciator panel.

PITCH TRIM

Red

Autopilot pitch trim failure.

Autopilot flight computer.

2.

Annunciator Panel Removal/Installation
A.

Remove Annunciator Panel (Refer to Figure 201).
(1) Ensure electrical power to airplane is OFF.
(2) Gain access to backside of annunciator panel and disconnect electrical connector.
(3) Remove screws securing annunciator panel to instrument panel and remove from airplane.

B.

Install Annunciator Panel (Refer to Figure 201).
(1) Connect electrical connector to annunciator panel.
(2) Position annunciator panel to instrument panel and secure using screws.
(3) Restore electrical power to airplane.
(4) Check annunciator panel for proper operation.

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MAINTENANCE MANUAL

A

B1746

.OR

0m
d]'^.
ELECTRI

ELECTRICAL
CONNECTOR
L

....

,

__

SCREW

DETAIL A

0585T1040
A051BT1022

Annunciator Panel Installation
Figure 201 (Sheet 1)

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CHAPTER

LANDING GEAR

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

Page 1
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32-Title
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32

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Apr 7/2003

LIST OF EFFECTIVE PAGES

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RECORD OF TEMPORARY REVISIONS
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Number

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
LANDING GEAR - GENERAL ...........................
Scope....................................
Definition ..................................
MAIN LANDING GEAR - TROUBLESHOOTING...................
Troubleshooting ...............................
MAIN LANDING GEAR - MAINTENANCE PRACTICES ...............
General...................................
Main Wheel Speed Fairing Removal/Installation ................
Brake Fairing Removal/installation.......................
Cap Fairing Removal/installation .......................
Tubular Strut Fairing Remova/Installation....................
Fuselage Fairing...............................
Main Landing Gear Removal/Installation....................
Step Bracket Removal/installation.......................
Alignment Inspection/Check ..........................
NOSE LANDING GEAR - TROUBLESHOOTING ..................
Troubleshooting ...............................
NOSE LANDING GEAR - MAINTENANCE PRACTICES ...............
Description and Operation ..........................
Nosewheel Speed Fairing Removal/Installation.................
Nose Landing Gear Removal/installation....................
Nose Landing Gear Steering Tube Removal/installation.............
Torque Link Removal/Installation .......................
Shimmy Damper Removal/Disassembly/Installation...............
Shock Strut Disassembly/Inspection/Assembly.................
Steering Rod Assembly Adjustment ......................
MAIN LANDING GEAR WHEEL AND AXLE - MAINTENANCE PRACTICES......
General...................................
Main Landing Gear Wheel Removal/Installation.................
Main Wheel Axle Removal/installation.....................
Main Wheel Disassembly/Assembly......................
Main Wheel Inspection/Check.........................
Wheel Balancing...............................
NOSE LANDING GEAR WHEEL - MAINTENANCE PRACTICES ...........
General...................................
Nose Landing Gear Wheel Removal/Installation ................
Nose Landing Gear Wheel Disassembly/Assembly ...............
Nose Landing Gear Wheel Inspection/Check..................
BRAKES - TROUBLESHOOTING .........................
Troubleshooting ...............................
BRAKE SYSTEM - MAINTENANCE PRACTICES ..................
Description and Operation ..........................
Brake Line Removal .............................
Brake Assembly and Line Removal/installation.................
Brake Component Inspection .........................
New Brake Lining Conditioning ........................
Master Cylinder Removal/Disassembly/Installation ...............
Brake System Bleeding............................
Parking Brake System ............................

© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
LANDING GEAR - GENERAL

1.

Scope
A.

2.

This chapter contains maintenance information concerning the landing gear and associated
components which provide a means of supporting, braking and steering the airplane during takeoff,
landing, taxiing, towing and parking.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The section on main landing gear provides troubleshooting, maintenance practices and
adjustment instructions for the main landing gear.
(2) The section on nose landing gear provides troubleshooting, maintenance practices and
inspection/checks for the nose landing gear.
(3) The section on wheels and brakes provides description/operation, troubleshooting, maintenance
practices and adjustment/test instructions for the main gear brake system.
(4) The section on nose gear steering provides troubleshooting, maintenance practices and
adjustment/test instructions for the nose gear steering system and related components.

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MAINTENANCE MANUAL
MAIN LANDING GEAR - TROUBLESHOOTING
1.

Troubleshooting

TROUBLE

PROBABLE CAUSE

REMEDY

AIRPLANE LEANS TO ONE SIDE.

Incorrect tire pressure.

Ensure tire is inflated to correct air
pressure.

Landing gear attaching parts not
tight.

Tighten loose parts or replace
defective parts with new parts.

Landing
gear
tubular
excessively sprung.

Replace tubular strut. Refer to
Main Landing Gear - Maintenance
Practices.

TIRES WEAR EXCESSIVELY.

Bent axle.

Replace axle.
Refer to Main
Landing Gear Wheel and Axle Maintenance Practices.

Incorrect tire pressure.

Ensure tire is inflated to 28 PSI air
pressure.

Main wheels out of alignment.

Check main wheel alignment.
Refer to Main Landing Gear Wheel
and Axle - Maintenance Practices.

Landing
gear
tubular
excessively sprung

TIRE BOUNCE EVIDENT
SMOOTH SURFACE.

ON

strut

strut

Replace tubular strut. Refer to
Main Landing Gear - Maintenance
Practices.

Bent axle.

Replace axle.
Refer to Main
Landing Gear Wheel and Axle Maintenance Practices.

Dragging brakes.

Adjust brakes. Refer to Brakes Maintenance Practices.

Wheel bearings excessively tight.

Properly install wheel bearings.
Refer to Main Landing Gear Wheel
and Axle - Maintenance Practices.

Tire out of balance.

Balance tire.
Refer to Main
Landing Gear Wheel and Axle Maintenance Practices.

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MAINTENANCE MANUAL
MAIN LANDING GEAR - MAINTENANCE PRACTICES
1.

2.

General
A.

The airplane is installed with fixed, tubular spring, steel main gear struts that are bolted into the
fuselage bottom. Attached to the outboard end of each strut is a die-cast aluminum wheel and disc
brake assembly.

B.

The maintenance practices give instructions for the fairing, strut and step bracket removal/installation.
Also included in this section are procedures for a check of the main wheel alignment.

C.

For the wheel and tire maintenance, refer to Main Landing Gear Wheel and Axle - Maintenance
Practices. For the brake maintenance, refer to Brakes - Maintenance Practices.

Main Wheel Speed Fairing Removal/Installation
A.

B.

Remove the Main Wheel Speed Fairings (Refer to Figure 201).
(1) Remove the screws that attach the brake fairing to the main wheel speed fairing.
(2) Remove the screws that attach the main wheel speed fairing to the attach plate, which is bolted
to axle.
(3) Remove the bolt that attaches the outboard side of the main wheel speed fairing to the axle nut.
(4) Loosen the mud scraper if necessary, and work the main wheel speed fairing from the wheel.
Install the Main Wheel Speed Fairings (Refer to Figure 201).
(1) Work the speed fairing over the wheel.

CAUTION: Damage will result if the correct clearance is not set between the
tire and the mud scraper. You must do a check of the clearance
every time the scraper has been moved, the tire changed, or the
speed fairings installed. If any mud, snow or ice collects on the
scraper, it will prevent the tire from correct rotation. You must clean
the scraper for correct tire rotation.
(2)

Complete a check of the clearance between the tire and scraper.
(a) Clean off any dirt or ice that has collected on the scraper.
(b) Adjust the clearance as necessary to have a minimum of 0.55 inch (14 mm) to a maximum
of 0.80 inch (20 mm).
(3) Install the bolt that attach outboard side of main wheel speed fairing to the axle nut.
(4) Install the screws that attach the main wheel speed fairing to the attach plate, which is bolted to
axle.
(5) Install the screws that attach the brake fairing to the main wheel speed fairing.
3.

4.

Brake Fairing Removal/Installation
A.

Remove the Brake Fairing (Refer to Figure 201).
(1) Remove the screws from the bottom side of the brake fairing.
(2) Remove the brake fairing from the landing gear.

B.

Install the Brake Fairing (Refer to Figure 201).
(1) Set the brake fairing over the landing gear.
(2) Install the screws in the bottom side of the brake fairing.

Cap Fairing Removal/Installation
A.

Remove the Cap Fairing (Refer to Figure 201).
(1) Remove the screws and clamp that attaches the cap fairing to the tubular strut fairing.
(2) Remove the cap fairing and clamp.

B.

Install the Cap Fairing (Refer to Figure 201).
(1) Set the cap fairing and clamp over the tubular strut.
(2) Attach the cap fairing with the screws and clamp.
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MAINTENANCE MANUAL

STEP
TREAD

STEP

/

STEP
BRACKET

DETAIL

C

FUSELAGE
FAIRING

STRUT
FAIRING
INBOARD
LANDING GEAR
BULKHEAD
BRAKE
FAIRING

TUBULAR'
STRUT

C

DING
EEL

STIFFENER

BRAKE

AIN WHEEL
PEED FAIRING

DETAIL A

0510T1007
A0541T3001
B0541T3002
C0741T1008

DETAIL B
Main Landing Gear Installation
Figure 201 (Sheet 1)

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5.

Tubular Strut Fairing Remova/Installation
A.

B.

6.

Remove the Tubular Strut Fairing (Refer to Figure 201).
(1) Remove the screws that attach the step to the step bracket.
(2) Remove the screws from the bottom side of the tubular strut fairing.
(3) Carefully remove the tubular strut fairing along the aft edge and move it over the step bracket.
(4) Pull the tubular strut fairing out of the fuselage fairing and remove it from the tubular strut.
Install the Tubular Strut Fairing (Refer to Figure 201).
(1) Set the tubular strut fairing over the tubular strut and position it over the step bracket and into
the fuselage fairing.
(2) Attach the tubular strut fairing with screws.
(3) Install the step to the step bracket.

Fuselage Fairing
A.

B.

Remove the Fuselage Fairing (Refer to Figure 201).
(1) Remove the main landing gear wheel. Refer to Main Landing Gear Wheel And Axle Maintenance Practices.
(2) Remove the main wheel speed fairing attach plate.
(3) Remove the brake torque plate.
(4) Remove the screws that attach the fuselage fairing to the fuselage.
(5) Move the fuselage fairing down the tubular strut and move it over the main landing gear axle.
Install the Fuselage Fairing (Refer to Figure 201).
(1) Move the fuselage fairing over the main landing gear axle and slide it up to the fuselage.
(2) Attach the fuselage fairing with screws.
(3) Install the brake torque plate.
(4) Install the main wheel speed fairing attach plate.
(5) Install the main landing gear wheel. Refer to Main Landing Gear Wheel And Axle - Maintenance
Practices.
CAUTION: Damage can result to the fairings if the tire pressure is not correct.
(6) Complete a check of the tire pressure and adjust it as necessary. Refer to Chapter 12, Tires Servicing.

7.

Main Landing Gear Removal/Installation
A. Remove the Main Landing Gear (Refer to Figure 201).
(1) Remove the front seat(s) to get access to the fuselage floor. Refer to Chapter 25, Equipment/
Furnishings - Maintenance Practices.
(2) Pull up the carpet and remove the floorboard access plate (231AT) to get access to the landing
gear components under the fuselage floorboard. Refer to Chapter 6, Access/Inspection Plates
- Description and Operation.

(3)
(4)
(5)
(6)
(7)
(8)

Jack the airplane. Refer to Chapter 7, Jacking - Maintenance Practices.
Remove the screws that attach the fuselage fairing to the fuselage.
Remove screws at the splice in the fuselage fairing.
Remove the fuselage fairing from the strut fairing.
Drain the hydraulic fluid from the brake line on the strut.
Disconnect the hydraulic brake line at the fitting where the brake line comes out from the fuselage
skin.
(9) Put a cap or plug on disconnected fittings.
(10) Remove the nut, washer and bolt the attach the inboard end of the tubular strut to the inboard
landing gear bulkhead fitting.

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CAUTION: Be careful when you remove the strut to prevent damage to the
hydraulic brake line.
(11) Pull the tubular strut from the fitting and bushing.
NOTE:
B.

8.

The tubular strut is a compression fit in the bushing in the outboard landing gear
forging.

Install the Main Landing Gear (Refer to Figure 201).
(1) Install all parts removed from strut.
(2) Apply U000992 grease to approximately 11 inches on the top end of the tubular strut. For the
grease supplier, refer to Chapter 12, Lubricants.
(3) Move the tubular strut into position through the bushing in the outboard strut fitting and into the
inboard strut fitting.
(4) Align the bolt holes in the tubular strut and the inboard fitting.
(5) Install the bolt through the tubular strut and the inboard fitting.
(6) Install the washer and nut on the bolt and tighten to a torque value of 100 foot-pounds, +8 or -8
foot-pounds (136 N.m., +11 or -11 N.m).
(7) Connect the hydraulic brake line to the fitting.
(8) Fill and bleed brake the system.
(9) Install the fuselage fairing.
(10) Remove the airplane from the jacks. Refer to Chapter 7, Jacking - Maintenance Practices.
(11) Install the floorboard access plate (231AT). Refer to Chapter 6, Access/Inspection Plates Description and Operation.
(12) Install the carpet and seat(s). Refer to Chapter 25, Equipment/Furnishings - Maintenance
Practices.

Step Bracket Removal/Installation
A.

Remove the Step Bracket (Refer to Figure 201).
(1) Remove the main landing gear fairings. Refer to Main Landing Gear Fairings Removal/
Installation.
(2) Remove the step bracket.
(a) Use long handled pliers or other similar tool to apply an upward force to the step support.
CAUTION: Do not continue to apply heat to the tubular strut to a
temperature where the paint or epoxy blisters.
(b) Apply heat to epoxy using heat gun, until epoxy softens and upward force of pliers breaks
step support away from landing gear strut. Quickly remove heat.
CAUTION: Do not finish sand the parts. A rough surface is necessary to get a
good bond.
(3) Use 180 grit aluminum oxide sandpaper or cloth to remove all the corrosion and old adhesive
from the step bracket and the tubular strut.
(4) Blend all nicks and scratches.

B.

Install the Step Bracket (Refer to Figure 202).
(1) Mark the position of the step support so that the new step support will be installed in the same
position on the strut.
(2) Clean the surfaces that you will bond together. If you use a solvent, make sure to remove all of
the solvent with a clean, dry cloth. It is important that the bonding surfaces are clean and dry.
(3) Make sure to do a check fit of the step support on the tubular strut. A small gap is acceptable
between the step support and the tubular strut.
(4) Apply primer to the step bracket. Refer to Chapter 20, Interior and Exterior Finish - Cleaning/
Painting.

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Apply primer to the tubular strut. Refer to Chapter 20, Interior and Exterior Finish - Cleaning/
Painting.
(6) Bond the step bracket to the tubular strut with EA9309 adhesive. Use the manufacturers
procedures to mix the adhesive.
(7) Apply a layer of adhesive on each of the bonding surface.
(8) Set the step bracket in position on the tubular strut.
(9) Use a clamp to attach the step bracket to the strut to make sure of a good, tight fit.
(10) Apply a small fillet of the adhesive at all edges of the bonded surfaces.
(5)

CAUTION: Do not set any weight on the step or strut until the sealant has fully
cured.
(11) Let the adhesive to fully cure. Refer to the manufacture's instructions.
(12) Apply paint to the tubular strut and step bracket after the adhesive is fully cured.
(13) Install the main landing gear fairings. Refer to Main Landing Gear Fairings Removal/Installation.
9.

Alignment Inspection/Check
A.

Check the Main Wheel Alignment (Refer to Figure 202).
(1) The toe-in limitations are 0.00 to 0.18 inch (0.00 to 4.57mm).
(2) The camber limitations are 2 to 4 degrees.
(3) If the wheel alignment is out of the limits, a new tubular spring strut will have to be installed.
NOTE:

There is no adjustment for the main landing gear strut.

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MAINTENANCE MANUAL

B1748

NOTE:

MAKE SURE THE FLOOR IS LEVEL IN THE WORK AREA. ATTACH A PLUMB BOB
FROM THE TAIL TIE-DOWN RING (AFT). LOOSEN THE FORWARD SCREW ON THE
COVER PLATE FOUND JUST AFT OF THE NOSE GEAR AND ATTACH A SECOND
PLUMB BOB TO THE COVER PLATE.

SQUARES

0541T1003
0541T1003

Main Wheel Alignment Check
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL

B1749

TOP VIEW OF THE TOE-IN CHECK
CARPENTER'S
SQUARE

FWD

STRAIGHTEDGE
MEASURE THE TOE-IN AT THE EDGES OF THE WHEEL FLANGE.
THE DIFFERENCE IN MEASUREMENTS IS THE TOE-IN FOR
ONE WHEEL. (HALF OF THE TOTAL TOE-IN.)

FRONT VIEW OF THE CAMBER CHECK
POSITIVE
CAMBER

NEGATIVE
CAMBER

INBD

HOLD THE PROTRACTOR LEVEL VERTICAL AGAINST THE
OUTBOARD FLANGES OF THE WHEEL TO MEASURE AND
READ THE CAMBER.

NOTE:

THESE PROCEDURES ARE FOR A MAIN WHEEL ALIGNMENT CHECK.
NO PROVISIONS ARE MADE TO ALIGN THE NOSE WHEEL. FOR CAMBER AND
TOE-IN SPECIFICATIONS, REFER TO CHAPTER 6, AIRPLANE DIMENSIONS AND
SPECIFICATIONS.
05411004
05411004

Main Wheel Alignment Check
Figure 202 (Sheet 2)

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MODEL 172
MAINTENANCE MANUAL
NOSE LANDING GEAR - TROUBLESHOOTING
1.

Troubleshooting

TROUBLE

PROBABLE CAUSE

REMEDY

NOSE WHEEL
SHIMMY.

Nose strut attaching bolts loose.

Tighten nose strut attaching bolts.

Loose or worn nose wheel steering
linkage.

Tighten linkage. Replace defective
parts with new parts.

Nose wheel out of balance.

Balance nose wheel. Refer to
Nose Landing Gear - Maintenance
Practices.

Wheel bearings too loose.

Properly install wheel bearings.

Defective shimmy damper.

Repair or install new damper.

Shimmy damper fluid low.

Service shimmy damper. Refer to
Chapter 12, Nose Gear Shimmy
Damper - Servicing.

Loose torque links.

Add shims, or install new parts as
required.

Defective strut seals.

Install new seals. Refer to Nose
Landing Gear - Maintenance
Practices.

Defective or loose air filler valve.

Check gasket and tighten loose
valve. Install new valve if defective.

Defective strut seals.

Install new seals. Refer to Nose
Landing Gear - Maintenance
Practices.

NOSE STRUT DOES
NOT HOLD AIR
PRESSURE.

HYDRAULIC FLUID
LEAKAGE FROM
NOSE STRUT.

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MAINTENANCE MANUAL
NOSE LANDING GEAR

-

MAINTENANCE PRACTICES

Description and Operation
A. The airplane has a steering nosewheel that is linked through the rudder pedals to give ground control.
Major components of the nose landing gear are as follows:
(1) Shock Strut - The shock strut is made of top and bottom machined cylinders that contain a
mixture of oil and air. The top and bottom cylinders give changes in the shock-absorb rates.
(2) Torque Links - The torque links give a mechanical link between the top and bottom parts of the
shock strut and help to keep the nosewheel aligned with the airframe.
(3) Nosewheel Steering - The nosewheel steering operates through the use of the rudder pedals.
The spring-loaded steering rod assemblies connect the nose gear steering arm assembly to the
arms on the rudder pedals. The steering gives up to approximately 10 degrees each side of
neutral, after which the brakes can be used to get a maximum deflection of 30 degrees right or
left of the center.
(4) Shimmy Damper (For airplanes with the Lord Shimmy Damper) - The shimmy damper uses
rubber with a lubricant to absorb nosewheel vibration. The damper is connected between the
shock strut and the steering arm assembly.
(5) Shimmy Damper (For airplanes that do not have the Lord Shimmy Damper) - The shimmy
damper gives resistance to shimmy when it moves hydraulic fluid through the small orifices in a
piston. The damper is connected between the shock strut and the steering arm assembly.
2.

Nosewheel Speed Fairing Removal/Installation
A. Speed Fairing Removal (Refer to Figure 201).
(1) Remove the bolt that attaches the cover plate to the bottom torque link and remove the cover
plate. Install the bolt.
(2) Weight or tie down the tail of the airplane to raise the nosewheel from the floor.
(3) Remove the nosewheel axle stud.
(4) Remove the bolt that attach the speed fairing and towbar spacers to the strut.
(5) Move the speed fairing up and remove the nosewheel. Loosen the scraper as necessary.
(6) Turn the speed fairing 90 degrees to center line of airplane and work the fairing down over the
fork to remove it.
B. Speed Fairing Installation (Refer to Figure 201).
(1) Move the speed fairing up over the nose gear fork with the speed fairing at 90 degrees to the
center line of the airplane.
(2) Move the speed fairing up and install the nosewheel in fork.
(3) Install the axle stud.
(4) Set the speed fairing over the nosewheel and tighten the axle stud nut until you feel friction when
the wheel is turned.
(5) Loosen the nut to the nearest castellation and install a cotter pin.
(6) Install the bolt, towbar spacers, washers, and the nut that attach the fairing to the strut.

CAUTION: Damage will result if the correct clearance is not set between the
tire and scraper. You must do a check of the clearance every time
the scraper moves or the tire is changed when you install the speed
fairings. If any mud, snow, or ice collects on the scraper, it will
prevent the tire from correct rotation. You must keep the scraper
clean for correct tire rotation.
(7) Complete a check of the clearance between the tire and the scraper.
(a) Clean off any dirt or ice that has collected on the scraper.
(b) Adjust the clearance as necessary to have aminimum of 0.55 inch (14 mm) to amaximum
of 0.80 inch (20 mm).
(8) Lower the nose of the airplane to the floor.
(9) Remove the bottom torque link attach bolt.
(10) Set the cover plate over the speed fairing and attach it with the bottom torque link attach bolt.

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NUT

DETAIL A
PLUG
0510T1 007
A05-42T1012
B05-42T1014

Nosewheel Speed Fairing Installation
Figure 201 (Sheet 1)

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3.

Nose Landing Gear Removal/installation
A. Nose Landing Gear Removal (Refer to Figure 202).
(1) Remove the cowl. Refer to Chapter 71, Cowl - Removal/installation.
(2) Weight or tie down the tail of the airplane to raise the nosewheel from the floor.
(3) Disconnect the nosewheel steering tubes from the nose gear steering collar.

CAUTION: Make sure the strut is fully deflated before you remove the bolt or
roll pin at the top of the strut.

B.

(4) Remove the strut clamp cap and shims from the bottom strut fitting.
(5) Deflate the strut fully and extend the strut to its shortest length.
(6) Remove the bolt from the top of the strut.
(7) Pull the strut assembly down from the top attach forging.
Nose Landing Gear Installation (Refer to Figure 202).
(1) Before you inflate the nose gear strut, install the top of the strut in the top attach forging and
attach it with a bolt.
(2) Extend the strut to connect the cap to the strut clamp with the bottom strut fitting on the firewall.
(3) Install the shims and the cap for the strut clamp attaching strut to lower strut fitting.
NOTE:

When you install the cap, examine the gap between the cap and the strut fitting before
the attach bolts are tightened. The gap tolerance is 0.01 0 inch (0.254 mm) minimum
and 0.01 6 inch (0.406 mm) maximum. Ifthe gap is more than the maximum tolerance,
install shims as necessary. Replace the cap with shims to get the correct gap if the
gap is less than the minimum. Install the shims as equal as possible between the
sides of the gap.

(4) Inflate and service the shock strut. Refer to Chapter 12, Nose Landing Gear Shock Strut Servicing.
(5) Rig the nosewheel steering tubes. Refer to Chapter 27, Rudder Control System - Maintenance
Practices.
(6) Remove the weights or the tie down from the tail, and lower the nosewheel to the floor.
(7) Install the cowl. Refer to Chapter 71, Cowl - Removal/installation.
4.

*
*

Nose Landing Gear Steering Tube Removal/installation
A.
Nose Landing Gear Steering Tube Removal (Refer to Figure 202).
(1) Remove the upholstery from the area below the instrument panel as necessary.
(2) Weight or tie down the tail of the airplane to raise the nosewheel from the floor.
(3) Loosen the clamp that holds the fire sleeve around the steering tube.
(4) From inside the airplane, remove the nut that attaches the ball joint part of the steering tube to
the rudder bar.
(5) Remove the bolt and the nut that attach the clevis on the steering tube to the rod end on the
nosewheel strut.
(6) Remove the steering tube from the airplane.
B. Nose Landing Gear Steering Tube Installation (Refer to Figure 202).
(1) From inside the airplane, attach the ball joint part of the steering tube to the rudder bar with the
nut.
~~(2) Loosen the jam nut.
(3) Turn the clevis until the holes in the rod end and the clevis align.
(4) Attach the clevis to the rod end with the bolt and the nut.
~~(5) Tighten the jam nut.
(6) Pull the fire sleeve down around the steering tube and attach it with the clamp.
(7) Remove the weights or the tie down from the tail and lower the nosewheel to the floor.
(8) Install the upholstery in the area below the instrument panel as necessary.

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BOLT

"'A
TUBE

SHIMNv

G TUBE

SHIMMY DAMPER A

DETAIL

A

051 OTi 007
A05421006

Nose Landing Gear Installation
Figure 202 (Sheet 1)

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B1752

DETAIL

B

LOWER
STRUT
FITTrI N

SHI

STEERING
TUBE
ASSEMBLY

NUT

LEVI

DETAIL

DETAIL

D

C

B0542R1013
C0542T1 007
D0542R81013

Nose Landing Gear Installation
Figure 202 (Sheet 2)

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REFER TO
SHEET 3

81755

lUT
PACKING
SUPPORT
RING BACI
RING

0-RING
PACKING
SUPPORT
RING
RETAINING
RING

SCRAPER
RING

/0-F
-~

BA(

RING
LOCK
RING

RIN
SCF
RINI

LOCK
RING
viEw A-A

TOWBAF
SPACER

FORK

O-RIN(
E0542 101 0
AA0S.42 1010

DETAIL E=
Nose Landing Gear Installation
Figure 202 (Sheet 3)

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B1756

0-RING

SNAP
RINGS

0-RINGS

DETAIL

F

F05421 003

Nose Landing Gear Installation
Figure 202 (Sheet 4)

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81754

FILLER
VALVE
E-MBLY
ioD

:ND
0-RING
ORIFICE
PISTON
SUPPORT.-

viEw B-B

UPPER
STRUT
NO. 40
0.098-INCH
HOLE

UPPER
STRUT

DECAL
VIEW C-C

C
RING

>C
ROD END
ROD
END~

SHIM
(AS REQUIRED)

REFER TO
SHEET 4

DETAIL

.. , -

- I

G

G05421010
BB05421 010
CC05421101 0

Nose Landing Gear Installation
Figure 202 (Sheet 5)

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(9) Do the rigging of the nosewheel steering tubes. Refer to Chapter 27, Rudder Control System
Maintenance Practices.
5.

-

Torque Link Removall/Installation
A. Torque Link Removal (Refer to Figure 202).

WARNING: Completely deflate the shock strut before you remove the
torque links.

B.

(1) Disconnect the top and bottom attach bolts, spacers, shims, and nuts.
(2) Remove the torque links.
Torque Link Installation (Refer to Figure 202).
NOTE:

If the safety lug and stop lug are removed from the top torque link during disassembly,
they must be installed and the retaining bolts tightened 20 to 25 In-lbs (2.26 to 2.82 N.m).
After you tighten the bolts, bend the tips of the safety lug to safety them into position.

(1) Install the top and bottom torque link assemblies with the shock strut fully deflated.
(2) Install the bolt that attaches the top and bottom assemblies.
(3) Tighten the nuts at each end of the torque links until they are almost tight. Then tighten the nuts
to align the next castellation with a cotter pin hole in the bolt.
(4) Examine the top and bottom torque link for looseness. If looseness is apparent, shims can be
installed to remove any slack. This will help to prevent nosewheel shimmy.
(5) Fill and inflate the shock strut to the correct pressure. Refer to Chapter 12, Nose Landing Gear
Shock Strut - Servicing.
6.

Shimmy Damper Removal/Disassembly/Installation
A.
Shimmy Damper Removal (Refer to Figure 202).

I
B.

NOTE:

~~~Shimmy
Dampener is discarded.

(1) Remove the cotter pin, nut, washer, and bolt that attach the piston shaft clevis to the bracket
that is welded on the bottom of the top strut tube.
(2) Remove the cotter pin, nut, spacer, and bolt that attach the housing to the steering arm assembly.
(3) Remove the shimmy damper.
(4) For airplanes with the Lord shimmy damper, discard the Lord Shimmy Damper.
Disassemble and Assemble the Hydraulic Shimmy Damper (Refer to Figure 202).
NOTE:

C.

There are no inspection or overhaul requirements for the Lord Shimmy Damper. The Lord

~

There are no inspection or overhaul requirements for the Lord Shimmy Damper. The Lord
Shimmy Dampener is discarded.

(1) Use Detail F as a guide to disassemble the shimmy damper. When you assemble the damper,
all of the new 0-rings must be used. All parts must be lubricated before you assemble with clean
hydraulic fluid.
(2) When the damper is fully assembled, it must be serviced using procedures in Chapter 12, Nose
Landing Gear Shimmy Damper - Servicing.
Shimmy Damper Installation (Refer to Figure 202).
(1) Before you install the shimmy damper, do the maintenance that follows:
(a) If a Lord Shimmy Damper has been in storage for a long period, make sure that the shaft
moves freely before you install it. Refer to Chapter 12, Nose Landing Gear Shimmy
Damper - Servicing.
(b) Make sure that the tire is in good condition, is balanced, and has no tears or foreign objects
in it.

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(c)

Examine the interface between the bottom of the steering collar and the top of the nose
gear fork. If there is looseness here, replace or add more shims under the collar.
(d) Examine the assembly hardware such as bolts and nuts for wear, and replace as
necessary.
(e) Examine the shimmy damper arm attach points on the landing gear and structure for wear
and replace as necessary.
(2) Attach the shimmy damper housing to the steering arm assembly with the bolt, spacer, nut, and
cotter pin.
(3) Attach the shimmy damper piston rod clevis to the bracket that is welded on the bottom of the
top strut tube with the bolt, washers (as necessary), and nut.
(4) For cleaning and servicing of the shimmy damper, refer to Chapter 12, Nose Landing Gear
Shimmy Damper - Servicing.
7.

Shock Strut Disassembly/InspectionlAssembly
A.

Dissemble the Shock Strut (Refer to Figure 202).
NOTE:

The procedures that follow apply to the nose gear shock strut after it has been removed
from the airplane and the speed fairings and nosewheel have been removed. If you
separate the top and the bottom strut, you do not have to remove or completely
disassemble the strut to do an inspection and parts installation.

WARNING: Make sure that you completely deflate the shock strut before
you remove the lock ring in the bottom end of the top strut and
before you disconnect the torque links.
(1) Remove the shimmy damper. Refer to Shimmy Damper Removal/Disassembly/Installation.
(2) Remove the torque links. Refer to Torque Link Removal/Installation.
(a) To help in assembly, record the position of the washers, shim, and spacers.
(3) Remove the lock ring from the groove inside the bottom end of the top strut.
NOTE:

There is a small hole at the lock ring groove to help you remove the lock ring.

NOTE:

Hydraulic fluid will drain from the strut halves as the bottom strut is pulled from the
top strut.

(4) Use a straight, hard pull to separate the top and bottom struts.
(a) Turn the bottom strut upside down and drain the hydraulic fluid.
(5) Remove the lock ring and the bearing at the top end of the bottom strut assembly.
(a) Make a mark on the top side of the bearing for assembly.
(6) Slide the packing support ring, scraper ring, retaining ring, and lock ring from the bottom strut.
(a) Make a mark at the relative position and the top side of each ring. Wire or tape the rings
together to be sure that you install them in the correct position.
(7) Remove the 0-ring and the backup rings from the packing support ring.
(8) Remove the bolt that attaches the towbar spacers.
NOTE:

The bolt that attaches the towbar spacers also holds the bushing and the base plug
in position.

(9) Remove the bolt that attaches the fork to the strut barrel.
(10) Remove the base plug and the metering pin from the bottom strut.
(11) Remove the 0-rings and the metering pin from the base plug.
NOTE:

The bottom strut barrel and fork are a press fit and are drilled on the assembly.
Separation of these parts is not recommended unless you install a new part.

(12) Remove the retaining ring that attaches the steering arm assembly on the top strut.

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B.

C.

(13) Remove the steering arm assembly, shims (if installed), and washer.
(a) If shims are installed, record the quantity and position of each shim.
(14) Push the orifice support from the top strut and remove the 0-ring.
(15) Remove the filler valve from the orifice support.
Inspect/Repair the Strut.
(1) Clean all the parts in cleaning solvent.
(2) Examine all the parts for damage and wear.
(3) Replace all parts that show wear or damage and all 0-rings and backup rings with new parts.
(4) Sharp metal edges must be smoothed with Number 400 emery paper and cleaned with solvent.
Assemble the Shock Strut (Refer to Figure 202).
NOTE:

All parts must be cleaned and lubricated with hydraulic fluid before assembly. All 0-rings
must be new.

(1) Install the washer and the shims.
(2) Lubricate the needle bearings in the steering collar.
(3) Install collar and retaining ring.
(4) Make sure the steering collar has a tight fit against washer.
(a) Shims of variable thicknesses are available from Cessna Aircraft Company to give a tight
fit for the collar against the washer. Refer to the Model 172 Illustrated Parts Catalog for
the shim numbers.
(5) Install the rod ends in the steering collar.
(6) Adjust the rod ends to the dimensions specified in View A-A.
(7) Install the 0-rings and filler valve in the orifice piston support.
(8) Install the orifice piston support in the top strut.
(9) Install the 0-ring and metering pin with the 0-ring in the base plug. Attach with a nut.
NOTE:

If the base plug is to be replaced, the new part will need to be line-drilled to accept
the NAS75-5 bushing.

(10) Install the bushing (if removed) in the base plug.
(11) Install the base plug assembly in the bottom strut.
(a) Align the holes of the bushing, hole in the bottom strut, and the hole in the fork.
(b) Install the towbar spacer under the head of the bolt.
(c) Install the bolt through the fork, bottom strut and bushing, which is installed in base plug.
(d) Install the towbar spacer on the threaded end of the bolt.
(e) Install and tighten the nut.
(12) Install the lock ring, retaining ring, and scraper ring on the bottom strut. Make sure they are
installed in the same positions before they were removed.
(13) Install the 0-rings and backup rings in the packing support ring.
(14) Move the packing support ring over the bottom strut.
(15) Install the bearing and the lock ring at the top end of the bottom strut assembly. Note top side
of bearing.
(16) Install the top strut assembly over the bottom strut assembly.
(17) Install the lock ring in the groove of the bottom end of the top strut.
(a) Set the lock ring in position so that one of its ends covers the small access hole in the lock
ring groove (View C-C).
(18) Install the torque links.
(a) Set the washers, shims, and spacers in the same positions as before they were removed.
(19) Install the shimmy damper.
(20) After the shock strut assembly is complete, install the strut on the airplane.
(21) Fill and inflate the strut. Refer to Chapter 12, Nose Landing Gear Shock Strut - Servicing.
8.

Steering Rod Assembly Adjustment
A. Adjustment Criteria (Refer to Figure 202).
(1) Adjust the rod ends to the dimension specified in Detail E, View A-A.

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(2) Attach the nosewheel steering rods to the rod ends protruding from the steering arm assembly.
NOTE:

The nosewheel steering and rudder systems are connected. An adjustment to one
system can have an effect on the other system and must be taken into consideration.

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MAIN LANDING GEAR WHEEL AND AXLE - MAINTENANCE PRACTICES
1.

General
A.

2.

The main landing gear wheel maintenance practices give removal/installation instructions for left main
wheel. The removal/installation for the right main wheel is typical.

Main Landing Gear Wheel Removal/Installation
NOTE:

3.

A.

Remove the Wheel (Refer to Figure 201).
(1) Lift the airplane with jacks. Refer to Chapter 7, Jacking - Maintenance Practices.
(2) Remove the speed fairing if it is installed. Refer to Main Landing Gear - Maintenance Practices.
(3) Remove the hub caps, cotter pin and the axle nut.
(4) Remove the bolts that attach the brake backing plate to the brake cylinder.
(5) Remove the backing plate.
(6) Pull the wheel from the axle.

B.

Install the Wheel (Refer to Figure 201).
(1) Set the wheel assembly on the axle.
(2) Install and tighten the axle nut until a you feel friction when the wheel is rotated.
(3) Loosen the nut to the nearest castellation.
(4) Install the cotter pin.
(5) Set the brake backing plate in position and attach with bolts.
(6) Install the hub cap.
(7) Install the speed fairing. Refer to Main Landing Gear - Maintenance Practices.

Main Wheel Axle Removal/Installation
A.

B.

4.

The wheel removal is not necessary to reline the brakes or to remove the brake parts, other than
the brake disc on the torque plate.

Remove the Axle (Refer to Figure 201).
(1) Remove the speed fairing. Refer to Main Landing Gear - Maintenance Practices.
(2) Remove the wheel. Refer to Main Landing Gear Wheel Removal/Installation.
(3) Disconnect, drain and put a cap or plug in the hydraulic brake line of the wheel brake cylinder.
(4) Remove the bolts that attach the brake torque plate and speed fairing mounting plate to the axle.
(5) Remove the cotter pin, nut, washer and bolt that attach the axle to the tubular strut.
(6) Remove the axle from the spring strut.
Install the Axle (Refer to Figure 201).
(1) Apply epoxy primer to the surfaces of the axle and tubular strut.
(2) Install the axle onto the tubular strut with the tapered edge on the bottom, when the primer is
wet.
(3) Install the bolt, washer and nut that attach the axle to the tubular strut.
(4) Install the cotter pin after you tighten the nut.
(5) Install the brake components and the speed fairing mounting plate to the axle.
(6) Install the wheel on the axle.
(7) Connect the hydraulic brake line to the wheel brake cylinder.
(8) Fill and bleed the hydraulic brake system. Refer to Brakes - Maintenance Practices.
(9) Install the main wheel speed fairing. Refer to Main Landing Gear - Maintenance Practices.

Main Wheel Disassembly/Assembly
A.

Disassemble the Wheel (Refer to Figure 202).
WARNING: DO NOT REMOVE THE WHEEL WITH THE TIRE AND TUBE
INFLATED WITH AIR. SERIOUS INJURY OR DEATH CAN
RESULT.
(1) Fully deflate the tire and tube.
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B

A
TUBULAR
STRUT
MAIN LANDING
GEAR AXLE
BRAKE
BACKPLATE

TIRE

-

COTTER PIN
HUB CAP

DETAIL A
0510T1007
A0541T3001

Main Wheel Installation
Figure 201 (Sheet 1)

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B

A,

RETAINING
RING
GREASE SEAL

GREASE SEAL
FELT

BEARING CONE
WHEEL HALF

TIRE

TUBE

NUT

/

WASHER

7

BEARING CUP

BEARING
CONE
AL

BEARING CUP

GREASE SEAL
FELT
GREASE SEAL
RETAINER

DETAIL A

RETAINING
RING
0510T1007
A0541T1001

Main Wheel Assembly
Figure 202 (Sheet 1)

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CAUTION: BE CAREFUL TO PREVENT TOOL DAMAGE TO THE TIRE
WHEN YOU REMOVE THE TIRE FROM THE WHEEL HALVES.
Break loose the tire bead.
Remove the bolts that attach the wheel halves together.
Separate and remove the tire and tube from the wheel halves.
Remove the retaining rings, grease seal retainers, grease seal felts, grease seal retainers and
bearing cones.
(6) The bearing cups (races) are a press fit in the wheel halves and must not be removed unless a
new part is to be installed.
(a) To remove the bearing cups, heat the wheel half in boiling water for 30 minutes or in an
oven, not to exceed 250°F (121°C).
(b) Use an arbor press if available, to press out bearing cup and press in a new bearing cup
while the wheel half is still hot.
(2)
(3)
(4)
(5)

B.

Assemble the Wheel (Refer to Figure 202).
(1) Apply a small quantity of SAE 10 oil for lubrication on the felt grease seal.
(2) Install the bearing cone, grease seal retainer, grease seal felt, grease seal retainer and retaining
ring into each wheel half.
(3) Install the tube in the tire. Make sure to align the index marks on the tire and tube.
(4) Set the wheel half into the tire and tube (side opposite valve stem).
(5) Install the bolt through the wheel half with a washer under the head of the bolt.
(6) Set the other wheel half into the other side of the tire and tube. Make sure to align the valve
stem in the valve slot.
(7) Make sure the tube is not pinched between the wheel halves before you torque the nuts.

CAUTION: MAKE SURE THE NUTS HAVE THE CORRECT TORQUE. THE
BOLTS CAN CAUSE DAMAGE OF THE WHEEL IF THE NUTS DO
NOT HAVE THE CORRECT TORQUE.
CAUTION: DO NOT USE IMPACT WRENCHES ON THE BOLTS OR NUTS.
(8) Install the washers and nuts on the bolts.
(9) Tighten the nuts to a dry torque of 90 inch-pounds, +2 or -2 inch-pounds (10.17 N.m, +0.23 or
-0.23 N.m).
(10) Inflate the tire to seat the tire beads.
(11) Adjust the air in the tire to the correct pressure.
5.

Main Wheel Inspection/Check
A.

Remove the Wheel. Refer to Main Wheel Removal/Installation.

B.

Disassemble the Wheel. Refer to Main Wheel Disassembly/Assembly.

C.

Inspect the Main Wheel (Refer to Figure 202).
(1) Clean all metal parts and grease seal felts in solvent, and dry thoroughly.
NOTE:

A soft bristle brush can be used to remove hardened grease, dust or dirt.

(2) Examine the wheel halves for cracks or damage.
(3) Examine the bearing cones, cups, retaining rings, grease seal retainers, grease seal felts and
grease seal retainers for wear or damage.
(4) Examine the bolts for cracks in the bolt head.
(5) Replace the wheel half if it is cracked or damaged.
(6) Replace damaged retainer rings and seals.
(7) Replace worn or damaged bearing cups and cones.
(8) Replace any worn or damaged bolts.
(9) Remove any corrosion or small nicks with a minimum of 320 grit sandpaper.
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(10) Clean and paint repaired areas with a layer of clear lacquer paint. Refer to Chapter 20, Interior
and Exterior Finish - Cleaning/Painting.
(11) Pack the bearings with MIL-PRF-81322 wheel bearing grease.

6.

D.

Assemble the Wheel. Refer to Main Wheel Disassembly/Assembly.

E.

Install the Wheel. Refer to Main Landing Gear Wheel Removal/Installation.

Wheel Balancing
A.

Tire wear that is not equal is usually the result of the wheel not correctly balanced. Replacement of
the tire will usually correct the condition.
(1) The light weight point of the tire is marked with a red dot on the tire sidewall. The heavy weight
point of the tube is marked with a contrasting color line (usually near the inflation valve stem).
When you install a new tire, set the marks adjacent to each other. The wheel can be statically
balanced but not dynamically balanced if a wheel shows indication of unbalance when you
service it.
NOTE:

Static balance is the balance of the control surface, which is balanced from its hinge point.
A tire that is not dynamically balanced will cause vibration and can be examined when the
tire rotates.

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NOSE LANDING GEAR WHEEL - MAINTENANCE PRACTICES
1.

General
A.

2.

3.

The maintenance practices for the wheel of the nose landing gear gives instructions for the nose wheel
removal/installation, nose wheel disassembly/assembly and the nose landing gear wheel inspection/
check.

Nose Landing Gear Wheel Removal/nstallation
A.

Remove the Wheel (Refer to Figure 201).
(1) Weight or tie down the tail of the airplane to lift the nose wheel from the floor.
(2) Remove the nose wheel axle stud.
(3) Pull the nose wheel assembly from the fork.
(4) Remove the axle tube from the nose wheel. Loosen the wheel scraper as necessary on airplanes
that are installed with a speed fairing.

B.

Install the Wheel (Refer to Figure 201).
(1) Install the axle tube in the nose wheel.
(2) Install the nose wheel assembly in the fork.
(3) Install the nose wheel axle stud.
(4) Tighten the axle stud until you feel friction when the wheel is rotated.
(5) Loosen the nut to the nearest castellation and install the cotter pins.
(6) Airplanes that are installed with speed fairings will require a check of the scraper clearance.
Refer to Nose Landing Gear - Maintenance Practices.

Nose Landing Gear Wheel Disassembly/Assembly
A.

Disassemble the Wheel (Refer to Figure 201).

WARNING: DO NOT REMOVE THE WHEEL WITH THE TIRE AND TUBE
INFLATED WITH AIR. SERIOUS INJURY OR DEATH CAN
RESULT.
(1) Fully deflate the tire and tube.
(2) Loosen the tire beads.
(3) Remove the bolts and washers.
CAUTION: BE CAREFUL TO PREVENT TOOL DAMAGE TO THE TIRE
WHEN YOU REMOVE THE TIRE FROM THE WHEEL HALVES.
(4) Separate and remove each wheel half from the tire and tube.
(5) Remove the retaining rings, grease seal retainer, felt grease seal, grease retainer and bearing
cone from each wheel half.
(6) Bearing cups (races) are a press fit in each wheel half and must not be removed unless a new
part is to be installed.
(a) To remove the bearing cups, heat the wheel half in boiling water for 30 minutes or in an
oven, no more than 250°F (121°C).
(b) Use an arbor press if available, to press out the bearing cup.
(c) Press in a new bearing cup with the wheel half is still hot.
B.

Assemble the Wheel (Refer to Figure 201).
(1) Apply a small quantity of SAE 10 oil for lubrication on the felt grease seal.
(2) Install the bearing cone, grease seal retainer, felt grease seal, grease seal retainer and retaining
ring into each of the wheel halves.
(3) Install the tube in the tire. Make sure to align the index marks on the tire and tube.
(4) Set the wheel half into the tire and tube.
(5) Install the bolt through the wheel half with the washer under the head of the bolt.

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B1759

A
RETAINING RING
GREASE SEAL RETAINER

.WHEEL HALF
G
SEAL
RETAINER

BEARING
CONE
WHEEL HALF
BEARING CUP

BEARING

BEARING CUP

CUP

WASHER
F

DETAIL A

RETAINING RING
0510T1007
A0542T1001

Nose Landing Gear Wheel Assembly
Figure 201 (Sheet 1)

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(6) Set the other wheel half into the other side of the tire and tube.
(a) Make sure to align the valve stem in the valve slot.
(7) Make sure the tube is not pinched between the wheel halves before you tighten the nuts.

CAUTION: MAKE SURE THE NUTS HAVE THE CORRECT TORQUE. THE
BOLTS CAN CAUSE DAMAGE TO THE WHEEL IF THE NUTS DO
NOT HAVE THE CORRECT TORQUE.
CAUTION: DO NOT USE IMPACT WRENCHES ONTHE BOLTS OR NUTS.
(8) Install the washers and nuts on the bolts.
(9) Tighten the nuts to a dry torque of 90 inch-pounds, +2 or -2 inch-pounds (10.17 N.m, +0.23 or
-0.23 N.m).
(10) Inflate the tire to seat the tire beads.
(11) Adjust the air in the tire to the correct pressure.
4.

Nose Landing Gear Wheel Inspection/Check
A.
B.

Remove the Wheel. Refer to Nose Landing Gear Removal/Installation.
Disassemble the Wheel. Refer to Nose Landing Gear Wheel Disassembly/Assembly.

D.

Inspect the Wheel (Refer to Figure 201).
(1) Clean all of the metal parts and felt grease seals in Stoddard solvent or equivalent, and dry fully.
(2) Examine the wheel halves for cracks or damage.
(3) Examine the bearing cones, cups, retaining rings, and seals for wear or damage.
(4) Examine the bolts and nuts for cracks in the threads or radius of the bolt heads.
(5) Replace cracked or damaged wheel half.
(6) Replace damaged retaining rings and seals.
(7) Replace any worn or cracked bolts or nuts.
(8) Replace worn or damaged bearing cups or cones.
(9) Remove any corrosion or small nicks with a minimum of 320 grit sandpaper.
(10) Clean and paint repaired areas with a layer of clear lacquer paint. Refer to Chapter 20, Interior
and Exterior Finish - Cleaning/Painting.
Assemble the wheel. Refer to Nose Landing Gear Wheel Disassembly/Assembly.

E.

Install the wheel. Refer to Nose Landing Gear Removal/Installation.

C.

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BRAKES - TROUBLESHOOTING
1.

I

Troubleshooting

TROUBLE

PROBABLE CAUSE

REMEDY

DRAGGING BRAKES.

Brake pedal binding.

Check and adjust properly. Refer
to Brakes - Maintenance Practices.

Parking brake linkage holding brake
pedal down.

Check and adjust properly. Refer
to Brakes - Maintenance Practices.

Worn or broken piston return spring in
master cylinder.

Repair, or install new master
cylinder. Refer to Brakes Maintenance Practices.

Restriction in hydraulic lines or
restrictions in compensating port in
master cylinder.

Drain brake line and clean inside of
brake line with filtered compressed
air. If cleaning lines fails to give
satisfactory results, the master
cylinder may be faulty and should
be repaired.

Worn, scored or warped brake disc.

Install new disc and brake linings.
Refer to Brakes - Maintenance
Practices.

Damaged or accumulated dirt
restricting free movement of wheel
brake parts.

Clean and repair or install new
parts as necessary. Refer to
Brakes - Maintenance Practices.

Leak in system.

If brake master cylinders or wheel
cylinder assemblies are leaking,
repair, or install new parts. Refer
to Brakes - Maintenance Practices.

Air in system.

Bleed system. Refer to Brakes Maintenance Practices.

Lack of fluid in master cylinders.

Fill and bleed system. Refer to
Brakes - Maintenance Practices.

Defective master cylinder.

Repair or install new parts as
necessary. Refer to Brakes Maintenance Practices.

BRAKES FAIL TO
OPERATE.

I

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BRAKE SYSTEM - MAINTENANCE PRACTICES
1.

2.

Description and Operation
A.

The hydraulic brake system is comprised of two master cylinders, located immediately forward of
the pilot's rudder pedals, brake lines and hoses, and single-disc, floating cylinder brake assemblies
located at each main landing gear wheel.

B.

The parking brake system is comprised of a pull-type handle and mechanical connections which are
linked to the rudder pedal assembly. Pulling aft on the brake handle applies mechanical pressure to
the rudder pedals, activating the brakes and locks the handle in place. Turning the handle 90 degrees
will release the parking brake and allow for normal operation through the rudder pedals.

C.

Brake operation is accomplished by pushing on the upper part of each rudder pedal. This motion is
mechanically transmitted to the respective brake master cylinder, and through fluid-carrying lines out
to the brake assembly where fluid pressure acts to exert friction (through brake pads) against brake
discs.

D.

For an illustration of brake system, refer to Figure 201. For an illustration of the brake master cylinder,
refer to Figure 202.

Brake Line Removal
A.

3.

Brake lines in the system are mostly metal, with flexible rubber lines installed near the master cylinders.
Rigid lines may be replaced in sections using pre-formed parts available from Cessna. Flexible lines
should be inspected for cracks, deterioration wear and damage, and are also available in replacement
assemblies through Cessna.

Brake Assembly and Line Removal/Installation
A.

Remove Brake Assembly (Refer to Figure 201).
(1) Ensure parking brake is OFF.
(2) Disconnect brake line at brake assembly.
(3) Remove bolts securing back plate and remove brake assembly.
NOTE:

If torque plate needs to be removed, wheel must be removed from axle. If brake disc
is to be removed, the tire and wheel assembly must be removed, deflated and split.

(4) Inspect components. Refer to Brake Component Inspection below.

4.

B.

Install Brake Assembly (Refer to Figure 201).
(1) Position brake assembly in place and secure using bolts. Torque from 80 to 90 In-lbs.
(2) Reconnect brake line and bleed brakes.

C.

Remove Brake Lining (Refer to Figure 201).
(1) Remove back plate.
(2) Pull brake cylinder out of torque plate and slide pressure plate off anchor bolts.
(3) Place back plate on a table with lining side down flat. Center a 9/64-inch punch in the roller rivet,
and hit the punch sharply with a hammer. Punch out all rivets securing the linings to the back
plate and pressure plate in the same manner.

D.

Install Brake Lining (Refer to Figure 201).
(1) Install new lining on back and pressure plates. Secure to plates using rivets.
(2) Position pressure plate on anchor bolts and place cylinder in position so that anchor bolts slide
into the torque plate.
(3) Install back plate with bolts and washers. Torque from 80 to 90 In-lbs.
(4) Burn in brake lining. Refer to procedure below.

Brake Component Inspection
A.

Brake components should be inspected as follows:
(1) Clean all parts except brake linings and O-rings in dry cleaning solvent and dry thoroughly.
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MAINTENANCE MANUAL

D.7:n
O

INSTRUMENT
PANEL ASSEMBLY

LOWER
INSTRUMENT
PANEL COVER

SPACER

SCREW
PARKING
BRAKE
VIEW A-A

j

E

N
N

TUBE

CLAMP
*^

CATCH

\

CLAMP

CABLE

N;-11

POSITIONING PIN
POSITIONING RACK
RUDDER
PEDALS

IF
TUBE
;EMB
ASSEMBLY
\BELLCRANK
BRACKET

DETAIL B
PRING
BRACKET

0514T1008
A-A0514T1011
A0514T3001
A0514T3003
B0514T1011

DETAIL A
Brake System Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1761

BRAKE
LINE

BRAK
LINE

DETAIL C
BRAKE
LINE

BRAKE
LINE

BRAKE
LINE

DETAIL

D

BRAKE
MASTER
CYLINDER

BRAKE
LINES

BRAKE
HOSE

DETAIL E
C0514T1009
D0514T1009
E0514T3002

Brake System Installation
Figure 201 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1762

GREASE SEAL
RING
GREASE SEAL
FELT
GREASE SEAL
RING

SNAP RING

GREASE SEAL
CONE

WHEEL HALF

TIRE

TUBE
NUT

RING CUP

WASHER

WHEEL
HALF
BEARING
CONE

BEARING CONE

TORQUE PLATE
TORQUE PLATE
BUSHING

LINING

GREASE SEAL
RING

BACK
LINING
BOLT
PISTON PISTON
O-RING
BLEEDER SCREW
0541T2001

Brake System Installation
Figure 201 (Sheet 3)

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MODEL 172
MAINTENANCE MANUAL
(2) Install all new O-rings. Ensure all components are clean and lubricated with brake fluid before
reinstallation.
(3) Check brake linings for deterioration and wear. Minimum allowable thickness is 3/32-inch.
(4) Inspect brake cylinder bore for scoring. A scored cylinder will leak or cause rapid O-ring wear.
Install a new brake cylinder if the bore is scored.
(5) If the anchor bolts on the brake assembly are nicked or gouged, they must be sanded smooth
to prevent binding with the pressure plate or torque plate. When new anchor bolts are installed,
press out old bolts and install new bolts with a soft mallet.
(6) Inspect wheel brake disc for thickness. Minimum thickness is 0.205 inch.
5.

New Brake Lining Conditioning
A.

Non-asbestos organic lining:
(1) Taxi airplane for 1500 feet with engine at 1700 RPM, applying brake pedal force as needed to
develop a 5 to 9 knot taxi speed.
(2) Allow brakes to cool for 10 to 15 minutes.
(3) Apply brakes and check to see if a high throttle static run up may be held with normal pedal
force. If so, burn-in is completed.
(4) If static run up cannot be held, allow brakes to completely cool then repeat steps 1 through 3 as
needed to successfully hold.

B.

Iron-based metallic lining:
(1) Perform two consecutive full stop braking applications from 30 to 35 knots. Do not allow the
brake discs to cool substantially between stops.
NOTE:

6.

Light brake usage can cause the glaze to wear off, resulting in reduced brake
performance. In such cases, the lining may be conditioned again following the
instructions set forth in this conditioning procedure.

Master Cylinder Removal/Disassembly/Installation
A.

Remove Master Cylinder (Refer to Figure 201).
(1) Remove front seats and rudder bar shield to access the brake master cylinders.
(2) Remove bleeder screw at wheel brake assembly and drain hydraulic fluid from brake cylinders.
(3) Disconnect parking brake and disconnect brake master cylinders from rudder pedals.
Disconnect hydraulic hose from brake master cylinders and remove cylinders.
(4) Plug or cap hydraulic fittings, hose and lines to prevent entry of foreign material.

B.

Disassemble Master Cylinder (Refer to Figure 202).
(1) Unscrew clevis and nut from piston.
(2) Remove filler plug.
(3) Unscrew cover and remove from piston.
(4) Remove piston and spring.
(5) Remove packing and back-up ring from piston.

C.

Inspect and Repair Master Cylinder.
(1) Repair is limited to installation of new parts and cleaning. Use clean hydraulic fluid as a lubricant
during reassembly of the cylinders. Replace packing and back-up ring. Filler plug must be
vented so pressure cannot build up during brake operation. If plug is not vented, drill a 1/16-inch
hole, 30 degrees from vertical. Refer to Figure 202, View A-A for vent location.

D.

Reassemble Master Cylinder (Refer to Figure 202).
(1) Install spring in cylinder body.
(2) Install back-up ring and packing in groove of piston.
(3) Install piston in cylinder body. Install cover over piston and screw cover into cylinder body.
(4) Install nut and clevis on piston.
(5) Install filler plug. Ensure vent hole is open.

E.

Install Master Cylinder (Refer to Figure 201).
(1) Connect hydraulic hoses to brake master cylinders and install cylinders.
(2) Connect brake master cylinders to rudder pedals and connect parking brake linkage.
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B1763

-7

landing light
ballast.

I

/Do a check for broken,
(disconnected, or loose wires
\Repair any that are found/

Engage the
circuit breakers.

Landing/Taxi Light Troubleshooting
Figure 101 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
LANDING/TAXI LIGHTS - MAINTENANCE PRACTICES
1.

2.

General
A.

Airplanes 17280001 thru 17281233 and Airplanes 172S8001 thru 172S9770 not incorporating MK17233-01 have an incandescent landing and taxi light installed. The landing and taxi lights are installed
on the left wing leading edge between WS 100.00 and WS 118.00. The landing and taxi lights are
controlled by two switches on the circuit panel assembly. The landing light is operated by the landing
light switch and the taxi light is operated by the taxi light switch.

B.

Airplanes 17281234 and On and Airplanes 172S9771 and On, and Airplanes 17280001 thru 17281233
and Airplanes 172S8001 thru 172S9770 incorporating MK172-33-01 have a high-intensity discharge
(HID) landing and taxi light installed. The landing and taxi lights have an igniter installed on the back
side of each light. A ballast is necessary for the operation of the HID bulbs. The ballast for the
landing light HID bulb (inboard bulb) is installed on a bracket that is attached to a wing leading-edge
rib inboard of the bulb. The ballast for the taxi light HID bulb (outboard bulb) is installed on a bracket
that is attached to a wing leading-edge rib outboard of the bulb. The wiring is almost the same as
the incandescent bulb installation, but there is one more cable necessary to connect the ballast to the
HID bulbs. The landing and taxi light switches, and the landing and taxi light circuit breakers for the
HID lighting system are the same as those for the incandescent lighting system.

Troubleshooting
A.

For troubleshooting of the HID landing and taxi light installation, refer to Chapter 33, Landing/Taxi
Lights - Troubleshooting.

3.

Light Adjustment
A.

4.

The landing and taxi lights are set to specified positions, but you can adjust them as necessary. The
procedures that follow give information on the correct landing and taxi light adjustment procedure.
The procedures that follow are typical for incandescent and HID lights.
(1) Park the airplane on a flat, level surface with the landing and taxi lights in front of a light-reflecting
object. Make sure that the waterline of the airplane is level and that the wings are level. Refer
to Chapter 8, Leveling - Maintenance Practices.
(2) Park the airplane so that the distance from the light-reflecting object to the rivet line on the bottom
of the front spar is approximately 3 feet.
(3) Set the landing light switch to the LAND position.
(4) Measure the distance from the floor to the center of the beam that shines on the light-reflecting
object. The correct distance is 74.41 inches.
(5) Set the landing light switch to the OFF position
(6) Set the taxi light switch to the TAXI position.
(7) Measure the distance from the floor to the center of the beam that shines on the light-reflecting
object. The correct distance is 73.29 inches.
(8) Set the taxi light switch to the OFF position.
(9) To adjust the beam to the correct position, add or remove washers between the spacers and the
plate.

Light Removal and Installation
NOTE:
A.

Removal and installation is typical for incandescent and HID landing and taxi lights.

Remove the Light (Refer to Figure 201).
(1) Disconnect the main battery from the airplane. Refer to Chapter 24, Battery - Maintenance
Practices.
(2) Set the landing light and the taxi light switches to OFF.
(3) Remove the screws that attach the lens assembly to the leading edge of the wing.
(4) Remove the screws, brackets, and nuts that hold the light in position against the plate.
NOTE:

Some airplanes that have the HID landing and taxi lights have an aluminum ring
installed between the HID landing and taxi lights and the bracket.
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

nanny

S

DETAIL A
AIRPLANES 17280001 THRU 17281233 AND
AIRPLANES 172S8001 THRU 172S9770
NOT INCORPORATING MK172-33-01
051 T1007
A052BR3001

Landing and Taxi Light Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B4006

HID LANDING
LIGHT BALLAST

SCREW

LIGHT

DETAIL A
AIRPLANES 17281234 AND ON AND
AIRPLANES 172S9771 AND ON AND
AIRPLANES 17280001 THRU 17281233
AND AIRPLANES 172S8001 THRU 172S9770
INCORPORATING MK172-33-01

A0528T1002

Landing and Taxi Light Installation
Figure 201 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
(5) Disconnect the electrical wires from the back side of the light and remove the light from the
airplane.
B.

Install the Light (Refer to Figure 201).
(1) Put the light at the correct wing location (between WS 100.00 and WS 118.00) and connect the
electrical wires to the light.
(2) With screws and nuts, attach the light to the bracket so the light is attached tightly against the
plate.
NOTE:

The top of the nuts is not flush with the lip of the plate. The remaining part of the nuts
is behind the plate at the screw opening.

NOTE:

Some airplanes that have the HID landing and taxi lights will have an aluminum ring
installed between the HID landing and taxi lights and the bracket.

(3) Install the lens assembly to the leading edge of the wing.
(4) Connect the main battery to the airplane. Refer to Chapter 24, Battery - Maintenance Practices.
(5) Set the landing light switch to LAND and the taxi light switch to TAXI.
(6) Do a check of the operation of the landing and taxi lights.
5.

High-Intensity Discharge (HID) Ballast Removal and Installation
NOTE:
A.

The procedures that follow are for airplanes that have the HID landing and taxi light installation.

Remove the HID ballast (Refer to Figure 201).
NOTE:

Removal and installation procedures are typical for the HID landing and taxi lights.

(1) Disconnect the main battery from the airplane. Refer to Chapter 24, Battery - Maintenance
Practices.
(2) Put the landing and taxi light switches in the OFF position.
(3) Remove the HID landing and taxi lights. Refer to Light Removal and Installation.
(4) Remove the screws and nylon washers that attach the HID ballast to the support bracket on the
wing leading-edge rib.
(5) Disconnect the electrical connectors from the HID ballast.
(a) Landing light connectors: PL010 and UL005.
(b) Taxi light connectors: PL011 and UL006.
(6) Remove the HID ballast from the airplane.
B.

Install the HID ballast (Refer to Figure 201).
(1) Disconnect the main battery from the airplane. Refer to Chapter 24, Battery - Maintenance
Practices.
(2) Put the landing and taxi light switches in the OFF position.
(3) Put the ballast at the correct wing location.
(a) Landing light: outboard side of the wing rib found at WS 100.00.
(b) Taxi light: inboard side of the wing rib found at WS 118.00.
(4) Connect the electrical connectors to the HID ballast.
(a) Landing light connectors: PL010 and UL005.
(b) Taxi light connectors: PL011 and UL006

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MODEL 172

MAINTENANCE MANUAL

CAUTION: Do not install the HID ballast to the support bracket without the
nylon shoulder washers between the HID ballast and the support
bracket and the nylon washers between the HID ballast and the
screw head. If the HID ballast is installed without the nylon washers,
an electromagnetic field in the wing structure can cause incorrect
operation of the magnetometer.
(5) Install the screws and nylon washers that attach the HID ballast to the support bracket on the
wing leading-edge rib.
(6) Install the HID landing and taxi lights. Refer to Light Removal and Installation.
(7) Connect the battery to the airplane. Refer to Chapter 24, Battery - Maintenance Practices.
(8) Set the landing light switch to LAND and the taxi light switch to TAXI.
(9) Do a check of the operation of the landing and taxi lights.

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MODEL 172
MAINTENANCE MANUAL
COURTESY WING LIGHTS - MAINTENANCE PRACTICES
1.

Description and Operation
A.

2.

Each wing is equipped with a courtesy light located near the strut/wing intersection. The left wing
light, the right right light and the rear dome light are connected in parallel on a single circuit. Pressing
the overhead light switch supplies power to all three lights.Pressing the overhead light switch again
removes power from all three lights.

Courtesy Wing Light Removal/Installation
A.

B.

Remove Light (Refer to Figure 201).
(1) Ensure electrical power to the airplane is OFF.
(2) Remove screws securing cover to underside of wing.
(3) Push in on lamp, rotate counterclockwise and remove lamp from bayonet socket.
Install Light (Refer to Figure 201).
(1) Insert lamp into bayonet socket. Turn clockwise until lamp seats in socket.
(2) Reinstall cover to underside of wing.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
A . _s

B1

TINNERMAN
D
C,'

r C\ AI

TINNE
NUT

T
N

3 SHOWN,
Lt-

I INNth-MMAN

SCREW

"'/

l

"'A I

I VVIINU ITrIIAL

DETAIL A
0510T1007
A0528T1001

Courtesy Wing Light Installation
Figure 201 (Sheet 1)

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CHAPTER

NAVIGATION

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

34-00-00

Page 1

Apr 7/2003

34-11-00

Pages 201 -213

Jul 3/2006

34-1 2-00

Pages 201-203

Apr 7/2003

34-13-00

Pages 201 -202

Jan 3/2005

34-20-00

Pages 201 -21 0

Jan 2/2006

34-21-00

Pages 201-202

Apr 7/2003

34-22-00

Pages 201-202

Jul 1/2007

34-23-00

Pages 201-203

Jan 3/2005

34 -30-00

Pages 201 -202

Jan 3/2005

34-50-00

Pages 201 -202

Jul 1/2005

34-50-10

Page 201

Janl1/2007

34-5 1-00

Pages 201-202

Apr 7/2003

34-52-00

Pages 201-204

Jul 3/2006

34-53-00

Pages 201-202

Jan 3/2005

34-53-01

Pages 201 -202

Jan 2/2006

34-53-10

Pages 201 -204

Jan 3/2005

34-54-00

Page 1

Jan 2/2006

34-54-00

Pages 201-202

Jan 2/2006

34-55-00

Pages 201-203

Jul 3/2006

34-60-01

Pages 201 -202

Jul 1/2005

34-60-10

Pages 201 -203

Jan 3/2005

34-Title
34-List of Effective Pages
34-Record of Temporary Revisions
34-Table of Contents

©Cessna Aircraft Company

34 - LIST OF EFFECTIVE PAGES

Page 1 of 1
Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
NAVIGATION - GENERAL.............................
Scope....................................
Definition ..................................

34-00-00 Page 1
34-00-00 Page 1
34-00-00 Page 1

PITOT/STATIC SYSTEM - MAINTENANCE PRACTICES...............
Description and Operation ..........................
Pitot Tube Removal/Installation ........................
Sump Assembly Removal/installation .....................
Pitot Tube Heater Insulation Removal/installation ................
Vertical Speed Indicator Removal/Installation..................
Alternate Static Source Valve Removal/Installation ...............
Blind Encoder Removal/Installation (For Airplanes without Garmin G1 000) ....
Altimeter Removal/Installation.........................
Airspeed Indicator Removal/Installation ....................
Pitot System Leak Test............................
Static System Leak Test ...........................
Blow Out the Lines..............................

34-11 -00
34-1 1-00
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Page 211
Page 211
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Page 212
Page 212

OUTSIDE AIR TEMPERATURE INDICATOR - MAINTENANCE PRACTICES .....
Description and Operation ..........................
OAT Probe Removal/Installation........................
Clock/OAT Indicator Removal/installation ...................

34-12-00
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34-12-00

Page
Page
Page
Page

201
201
201
201

AIR DATA COMPUTER - MAINTENANCE PRACTICES ...............
General...................................
Troubleshooting ...............................
GDC 74A Air Data Computer Removal/Installation ...............
ATTITUDE AND DIRECTION - MAINTENANCE PRACTICES.............
General...................................
Operation Notes...............................
Precautions.................................
Prepare the Gyroscopic Instruments for Shipping................
Horizon Attitude Gyro Description and Operation ................
Horizon Gyro Removal and Installation.....................
Horizon Attitude Gyro Operational Check....................
Directional Gyro Description and Operation...................
Directional Gyro Removal and Installation (Airplanes without Garmin G-1000)...
Directional Gyro Operational Check ......................
Turn Coordinator Removal and Installation (Airplanes without Garmin G1 000) ....
Turn Coordinator Removal and Installation (Airplanes with Garmin G1OQO) ....

34-13-00
34-13-00
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Page 205
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Page 206
Page 207
Page 208
Page 209

COMPASS INSTALLATION - MAINTENANCE PRACTICES .............
General...................................
Compass Removal/Installation ........................

34-2 1-00 Page 201
34-21 -00 Page 201
34-21 -00 Page 201

MAGNETOMETER - MAINTENANCE PRACTICES .................
General...................................
Troubleshooting ...............................
GMU 44 Magnetometer Removal/Installation..................

34-22-00
34-22-00
34-22-00
34-22-00

Page
Page
Page
Page

201
201
201
201

ATTITUDE HEADING REFERENCE SYSTEM (AHRS) - MAINTENANCE PRACTICES
General...................................
Troubleshooting ...............................
GRS 77 AHRS Removal/installation......................
AHRS and Magnetometer Checkout Procedure.................

34-23-00
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34 - CONTENTS

Page 1 of 3
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
MARKER BEACON - MAINTENANCE PRACTICES.................
General...................................
Audio Panel Removal/installation .......................
Marker Beacon Antenna Removal/installation..................

34-30-00
34-30-00
34-30-00
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Page
Page
Page
Page

NAV/COM - MAINTENANCE PRACTICES .....................
General ..................................
Nay Antenna Removal/installation.......................
Nay Antenna Coupler Removal/Installation...................
Nay Indicator Removal/Installation.......................

34-50-00
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GIA 63 INTEGRATED AVIONICS INSTALLATION - MAINTENANCE PRACTICES ...
General...................................
Troubleshooting ...............................
GIA 63 Integrated Avionics Unit Removal/Installation ..............

34-50-10
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GPS

34-51 -00
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Page

201
201
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201

KR-87 ADF SYSTEM - MAINTENANCE PRACTICES ................
General...................................
KR-87 ADF Receiver Removal/installation (Airplanes without Garmin G1 000) ..
KR-87 ADF Receiver Removal/Installation (Airplanes with Garmin G1000) ....
KA-44B ADF Antenna Removal/Installation (For Airplanes With or Without Garmin
G100) ..................................
KI-227 ADF Indicator Removal/Installation ...................

34-52-00
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Page

201
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201

KT76C TRANSPONDER - MAINTENANCE PRACTICES...............
General...................................
Transponder Removal/installation.......................
Transponder Antenna Removal/Installation...................

34-53-00
34-53-00
34-53-00
34-53-00

KT-73 MODE S TRANSPONDER - MAINTENANCE PRACTICES...........
General...................................
KT-73 Mode S Transponder Removal and Installation..............

34-53-01 Page 201
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GTX 33 TRANSPONDER - MAINTENANCE PRACTICES ..............
General...................................
Troubleshooting ...............................
GTX 33 Transponder Removal/Installation...................
Transponder Antenna Removal/Installation...................

34-53-1 0
34-53-10
34-53-1 0
34-53-1 0
34-53-1 0

MAINTENANCE PRACTICES........................
General...................................
GPS Removal/installation...........................
G PS Antenna Removal/Installation ......................
-

201
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34-54-00 Page 1
34-54-00 Page 1

GDL-69A FIS - DESCRIPTION AND OPERATION..................
General...................................
GDL-69A FIS - MAINTENANCE PRACTICES....................
General...................................
GDL-69A XM Weather Data Link Removal/Installation..............

34-54-00 Page 201
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DME

34-55-00
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34-60-01
34-60-01
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Page
Page
Page
Page

201
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- MAINTENANCE PRACTICES........................
General...................................
KN-63 DME Receiver Removal/Installation...................
DME Antenna Removal/installation ......................

KMD-540 MULTI-FUNCTION DISPLAY - MAINTENANCE PRACTICES ........
General...................................
KMD-540 Multi-Function Display (MFD) Removal and Installation ........
Operational Check of the MD-540 Multi-Function Display ............

34 - CONTENTS
© Cessna Aircraft Company

Page 2of 3
Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
GARMIN DISPLAY UNIT (GDU) - MAINTENANCE PRACTICES ...........
General...................................
Troubleshooting ...............................
Control Display Unit Removal/Installation ... .................

©D Cessna Aircraft Company

34-60-10
34-60-10
34-60-10
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34 - CONTENTS

Page
Page
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Page

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Page 3 of 3
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
NAVIGATION - GENERAL
1.

Scope
A.

2.

This chapter describes the navigation systems, units, and components which provide airplane
navigational information. Included are pitot/static temperature, gyros, compass, VOR and indicators.
For King KAP140 Autopilot information refer to Chapter 22.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the table of Contents will further assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The Flight Environmental Data Section describes systems that sense environment conditions,
and use data to influence navigation of the airplane. This includes systems that depend on pitot
and static information.
(2) The Attitude and Direction Section describes systems that use magnetic gyroscopic and inertia
forces. This includes items like gyros, compass, magnetic heading, and turn and bank.
(3) The Dependent Position Determining Section describes systems that provide information to
determine position, and are mainly dependent on ground installation. This includes systems
like VOR, ADF, GPS, and transponders.

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MODEL 172
MAINTENANCE MANUAL
PITOT/STATIC SYSTEM - MAINTENANCE PRACTICES
1.

2.

Description and Operation
A.

The pitot system supplies ram air pressure to the airspeed indicator. The static system connects
the vertical speed indicator, altimeter, and airspeed indicator to atmospheric pressure through
plastic tubing connected to a static port. A static line sump is installed at the source button to
collect condensation in the static system. A heated pitot tube is standard, with the heating element
controlled by a switch on the instrument panel and powered by the electrical system. An alternate
static source valve is installed on the instrument panel to use when the external static source is not
in operation. Refer to Figure 201 for the pitot/static system schematic.

B.

On airplanes with an autopilot, there is a tube that connects the autopilot to a static port on the left
side of the airplane at FS 117.25. This part of the pitot/static system is not connected to the other
parts of the pitot/static system.

C.

Correct maintenance of pitot and static system is essential for correct operation of altimeter, vertical
speed and airspeed indicators, and, if installed, the autopilot. Leaks, moisture, and blockage can have
an effect on the readings of the instruments. Under instrument flight conditions, you must use the
instrument readings for the safe operation of the airplane. Keep the system clean and all instruments
and all parts of the system correctly attached to the airplane. Keep the pitot tube and static ports clean
with no blockage.
(1) Test the pitot/static system in accordance with the time limits set forth in Chapter 5, Inspection
Time Limits, or anytime components or lines within the system are opened. Refer to 14 CFR
91.411.

Pitot Tube Removal/Installation
A.

B.

Pitot Tube Removal (Refer to Figure 202).
(1) Remove the screws that attach the pitot tube to the wing and remove the pitot tube.
(2) Disconnect the ram air tube from the pitot.
(3) Disconnect the electrical connectors from the pitot heater and the pitot heat ground.
Pitot Tube Installation (Refer to Figure 202).

CAUTION: Do not blow through the pitot lines toward the instrument, as damage
will occur to the instruments.
CAUTION: You must keep the pitot tube assembly clean and all system components
free of blockage and leaks for correct operation.
(1) Connect the ram air tube to the pitot.
(2) Connect the electrical connectors to the pitot heater and the pitot heat ground.
(3) Do a check of the system for leaks. Refer to Pitot System Leak Test.
3.

Sump Assembly Removal/Installation
NOTE:

The removal/installation is typical for the two sump assemblies.

A.

Sump Assembly Removal (Refer to Figure 202).
(1) Get access to the sump assembly.
(2) Loosen the nut that connects the static tube to the sump assembly nipple.
(3) Turn the sump assembly and remove the sump assembly from the elbow.

B.

Sump Assembly Installation (Refer to Figure 202).
(1) Attach the sump assembly to the elbow. Apply Teflon® tape (U000912) as necessary where
plastic and metal connections interface.
(2) Connect static tube to the sump assembly nipple with nut.
(3) Do a leak check. Refer to the Static Pressure System Inspection and Leakage Test.

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MODEL 172
MAINTENANCE MANUAL

B227

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HEATED PITOT TUBE
Al RSPEED

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AIRPLANES WITHOUT GARMIN G1000

0595T1001

Pitot/Static System Schematic
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B5979

AUTOPILOT

SOURCE

LEGEND
PITOT
/
XO STATIC

059 I5T1001

AIRPLANES WITH AUTOPILOT

Pitot/Static System Schematic
Figure 201 (Sheet 2)

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MODEL 172
MAINTENANCE MANUAL

B5980

HEATED PITOT TUBE
AIRSPEED
INDICATOR

I///////////

AIR DATA
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ALTERNATE STATIC AIR SOURCE KNOB
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0595T1001

Pitot/Static System Schematic
Figure 201 (Sheet 3)

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MODEL 172
MAINTENANCE MANUAL
-

IBAA

PITOT LINE
(TO AIRSPEED
INDICATOR)
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D

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0510T1007
A0518R1046
B0518T1040

AIRPLANES WITHOUT GARMIN G1000
Pitot/Static System Installation
Figure 202 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

B3262

PITOT TUBE
HEATER ASSEMBLY
WIRE LEADS

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Pitot/Static System Installation
Figure 202 (Sheet 2)

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MODEL 172
MAINTENANCE MANUAL

B5985

/

/

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AIRPLANES WITH KAP-140 AUTOPILOT

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Pitot/Static System Installation
Figure 202 (Sheet 3)

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MODEL 172

MAINTENANCE MANUAL

B59ss

I

AIR DAT
COMPU

DETAIL E
AIRPLANES WITH GARMIN G1000
E0518T1152

Pitot/Static System Installation
Figure 202 (Sheet 4)

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MAINTENANCE MANUAL

4.

Pitot Tube Heater Insulation Removal/lnstallation.
A.

Pitot
(1)
(2)
(3)

Tube Heater Insulation Removal (Refer to Figure 202).
Set the ALT/BATT Master Switch to OFF.
Make sure that the PITOT HEAT/OFF switch is put in the OFF position.
Remove the 510BB access plate. Refer to Chapter 6, Access/Inspection Plates - Description
And Operation.

CAUTION: Do not disconnect the pitot ram air tube from the pitot tube.
(4) Remove the screws that attach the pitot tube to the wing.
(5) Remove and discard all nylon spiral wrap insulation.
B.

Pitot Tube Heater Insulation Installation (Refer to Figure 202).
(1) Cut new nylon spiral wrap into two pieces. Make one piece that is 4.0 inches in length and make
one piece that is 8.0 inches in length.
(2) Start 0.10 inch from the pitot tube and install the 4.0-inch piece of spiral wrap around the pitot
tube heater assembly.
(a) Trim as necessary.

CAUTION: Do not let the pitot heater assembly wire leads touch the pitot ram
air tubing, wire bundles, or heat-sensitive components. The pitot
tube heater assembly wire leads operate at high temperatures.
(3) Install the 8.0-inch piece of spiral wrap around the pitot ram air tube.
(a) Trim as necessary.
(4) Attach the pitot tube to the wing with the screws.

CAUTION: Do not blow through the pitot lines toward the instrument, as
damage will occur to the instruments if you do.
CAUTION: Keep the pitot tube assembly clean and make sure that all system
components are free of blockage and leaks for correct operation.
(5) Install the 510BB access plate. Refer to Chapter 6, Access/Inspection Plates - Description And
Operation.
(6) Connect electrical power to the airplane as necessary.
5.

6.

Vertical Speed Indicator Removal/Installation
A.

Vertical Speed Indicator (VSI) Removal (Refer to Figure 203).
(1) Remove the screws that attach the flight instrument panel to the instrument panel.
(2) Disconnect the static tube and the electrical connector from the VSI.
(3) Remove the screws that attach the VSI to the flight instrument panel.
(4) Remove the VSI from the airplane.

B.

Vertical Speed Indicator (VSI) Installation (Refer to Figure 203).
(1) Put the VSI on the flight instrument panel and attach it with screws.
(2) Connect the static tube and the electrical connector to the VSI.
(3) Attach the flight instrument panel to the instrument panel with the screws.
(4) Do a check of the system for leaks. Refer to the Static System Leak Test.

Alternate Static Source Valve Removal/Installation
A.

Alternate Static Source Valve Removal (Refer to Figure 202).
(1) Behind the stationary control panel, loosen the nuts that attach the two static tubes to the
alternate static source valve. Disconnect the static tubes from the alternate static source valve.
(2) Remove the screws that attach the alternate static source valve to the stationary control panel.
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MAINTENANCE MANUAL

ISPEED
DICATOR

COMPUTER

DETAIL A
AIRPLANES WITH
GARMIN G1000

0510T1007
A0718R1006
A0518T1151

Pitot and Static System Indicator Installation
Figure 203 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
(3)
B.

7.

Remove the alternate static source valve from the airplane.
Alternate Static Source Valve Installation (Refer to Figure 202).
(1) Put the alternate static source valve behind the stationary control panel and attach the static
tubes with the nuts.
(2) Attach the alternate static source valve to the stationary control panel with the screws.

Blind Encoder Removal/Installation (For Airplanes without Garmin G1000)
A. Blind Encoder Removal (Refer to Figure 202).
NOTE:

The blind encoder is under the dash on the copilot side.

(1) Disconnect the static tube and the electrical connector and remove the encoder from the
airplane.
(2) Loosen the knurled knob and remove the encoder from the mount.
B.

8.

9.

10.

Blind
(1)
(2)
(3)

Encoder Installation (Refer to Figure 202).
Put the encoder on the mount and attach with the knurled knob.
Connect the static tube and the electrical connector to the encoder.
Do a check of the system for leaks. Refer to the Static System Leak Test.

Altimeter Removal/nstallation
A.

Altimeter Removal (Refer to Figure 203).
(1) To get access to the back of the altimeter, remove the screws that attach the flight instrument
panel to the instrument panel.
(2) Disconnect the static tube and the electrical connector from the altimeter.
(3) Remove the screws that attach the altimeter to the flight instrument panel.
(4) Remove the altimeter from the airplane.

B.

Altimeter Installation (Refer to Figure 203).
(1) Put the altimeter on the flight instrument panel and attach it with screws.
(2) Connect the static tube and the electrical connector to the altimeter.
(3) Attach the flight instrument panel to the instrument panel with the screws.
(4) Do a check of the system for leaks. Refer to the Static System Leak Test.

Airspeed Indicator Removal/Installation
A.

Airspeed Indicator Removal (Refer to Figure 203).
(1) Remove the screws that attach the flight instrument panel to the instrument panel to get access
to the back of the airspeed indicator.
(2) Disconnect the static tube and the electrical connector from the airspeed indicator.
(3) Remove the screws that attach the airspeed indicator to the flight instrument panel.
(4) Remove the airspeed indicator from the airplane.

B.

Airspeed Indicator Installation (Refer to Figure 203).
(1) Put the airspeed indicator on the flight instrument panel and attach with the screws.
(2) Connect the static tube and the electrical connector to the airspeed indicator.
(3) Attach the flight instrument panel to the instrument panel with the screws.
(4) Do a check of the system for leaks. Refer to the Static System Leak Test.

Pitot System Leak Test
A.

Test Procedures.
(1) Put a piece of tape over the small hole in the lower aft end of the pitot tube.
(2) Attach a piece of rubber or plastic tubing over the pitot tube and close the opposite end of the
tube.
(3) Slowly roll up the tube until the airspeed indicator shows in cruise range.

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MAINTENANCE MANUAL
(4) Attach the tube to prevent air pressure change, and look at the airspeed after one minute. If
there is a leak, the pressure in the system is reduced, and you will see a lower airspeed on the
airspeed indicator.
(5) If there is a leak in the system, you must examine and tighten all connections, hoses, and fittings
before you do another check.
(6) If there are no leaks, slowly unroll the tubing to let the pressure in the instrument slowly return
to ambient pressure.
11.

Static System Leak Test
A.

Test Procedures.
(1) Make sure that the static system is free from moisture that is caught in the system, and that there
are no restrictions in the system.
(2) Make sure that there are no changes in or deformations to the airframe surface that can affect
the relation between the air pressure in the static pressure system and true ambient static air
pressure for any flight configuration.
(3) Close the static pressure alternate source control.
(4) Attach a vacuum source to the static pressure source opening.
(5) Slowly apply the vacuum source until the altimeter indication is a 1,000-foot increase in altitude.
(6) Cut off the vacuum source to make sure that there is a closed system for one minute.
(7) If the altimeter loss is not more than 100 feet after one minute, the system is good and you can
slowly release the vacuum until the system goes back to ambient. If the altimeter loss is more
than 100 feet, tighten all connections and do the leak test again. If the rate continues to be more
than the maximum allowable, do as follows.
(a) Disconnect the static pressure lines from the airspeed indicator and the vertical speed
indicator. Use suitable fittings to connect the lines together so that the altimeter is the only
instrument connected into the static pressure system.
(b) Do the leakage test again to see if the static pressure system or the instruments that you
bypassed are the cause of the leakage. If the instruments are the cause of the leak, you
must have the instruments repaired by an approved repair station, or replaced. If the static
pressure system is the problem, do as follows.

CAUTION: Do not apply positive pressure with the airspeed indicator or
the vertical speed indicator connected to the static pressure
system.
1
2
3
4
5
12.

Attach a source of positive pressure to the static source opening.
Slowly apply positive pressure until the altimeter indication decreases 500-feet, and
stops on this value.
Put a solution of mild soap and water on the line connections and the static source
flange, and look for bubbles to find leaks.
Tighten all leaking connections. Repair or replace all damaged parts.
Connect the airspeed and the vertical speed indicators into the static pressure system
and do the static system leak test again.

Blow Out the Lines

CAUTION: Do not blow through the pitot or static lines toward the instrument as damage
will occur to the instrument.
A. Pitot Lines.
(1) Although the pitot system drains down to the pitot tube opening, condensation can collect at other
areas in the system and cause some blockage of the line. To remove the blockage, disconnect
the line at the airspeed indicator. With low-pressure air, blow from the indicator end of the line
toward the pitot tube.

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MODEL 172
MAINTENANCE MANUAL

I

B.

Static Lines.
(1) Keep static lines clear and keep connections tight. All models have a static source sump which
collects moisture and keeps the system clear. If necessary, disconnect the static line at the first
instrument to which it is connected, and then blow line clear with low-pressure air.

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MODEL 172
MAINTENANCE MANUAL
OUTSIDE AIR TEMPERATURE INDICATOR - MAINTENANCE PRACTICES
1.

Description and Operation
A.

Outside air temperature is measured using a remote-mounted probe connected to a cockpit-mounted
indicator.
(1) The OAT (outside air temperature) probe is mounted on the upper cabin roof line at FS 46.46.
This probe transmits an electrical millivolt signal to the cockpit mounted gauge through a pair
of wires which route above the cabin headliner, through the left side windshield pillar, and
terminating behind the instrument panel.
(2) The cockpit-mounted indicator is located in the upper left portion of the instrument panel. The
indicator also incorporates a digital clock and voltage-reading functions. Inputs into the indicator
include 28.0 VDC for power, internal lighting and keep-alive clock functions, and millivolt inputs
from the temperature probe.
NOTE:

B.

2.

The indicator has provisions for a single 1.5 VDC "AA" battery used to power the
clock independent of airplane power. This battery, if installed, should be replaced
every two years.

Maintenance practices consist of removal and installation of the probe and indicator. The probe and
indicator are not matched, and may be replaced independent of each other. Probe replacement will
require new shielded terminal pins to be attached at the indicator end of the probe.

OAT Probe Removal/Installation
A.

Remove Probe (Refer to Figure 201).
(1) Remove overhead console. Refer to Chapter 25, Interior Upholstery - Maintenance Practices,
Figure 201.
(2) From outside of cabin, loosen and remove nut securing probe to roof skin.
(3) From inside of cabin, withdraw probe through roof skin.
(4) Remove interior panels as required to free probe wiring from airplane structure.
(5) Disconnect electrical connector from backside of OAT/Clock indicator.
(6) Remove probe pins from electrical connector.

B.

Install Probe (Refer to Figure 201).
(1) Install new terminal pins to end of replacement probe. Ensure shielded wiring is properly
grounded. Refer to Model 172R Wiring Diagram Manual, Chapter 20, Bonding and Grounding
- Maintenance Practices.

(2)
(3)
(4)
(5)
(6)
3.

Install terminal pins into electrical connector.
Reconnect electrical connector to backside of OAT/Clock indicator.
Reroute probe wiring in cabin area, and insert probe and ground lug through roof skin.
From outside of cabin, install metal washer (with o-ring insert) and hex nut to probe. Tighten
until o-ring compresses and forms a water-tight seal.
Reinstall interior panels and overhead console. Refer to Chapter 25, Interior Upholstery Maintenance Practices, Figure 201.

Clock/OAT Indicator Removal/nstallation
A.

Remove Indicator (Refer to Figure 201).
(1) Remove fuse F4 from the power junction box.
(2) Remove screws securing instrument sub panel to airplane structure.
(3) Withdraw sub panel aft to gain access to electrical connector.
(4) Remove electrical connector from OAT indicator.
(5) Remove screws securing OAT indicator to sub panel.

B.

Install Indicator (Refer to Figure 201).
(1) Secure OAT indicator to instrument sub panel using screws.
(2) Connect electrical connector to backside of OAT Indicator.
(3) Reinstall instrument sub panel to airplane structure.
(4) Reinstall fuse F4 to power junction box.

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MODEL 172
MAINTENANCE MANUAL

,..

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0510T1007
A0518R1067

Outside Air Temperature Installation
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
(5) Test for proper operation. Refer to Pilot's Operating Handbook and FAA Approved Airplane
Flight Manual, Supplements, for operation/test instructions.

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MODEL 172

MAINTENANCE MANUAL
AIR DATA COMPUTER - MAINTENANCE PRACTICES
1.

General
A.

B.
2.

Troubleshooting
A.

3.

On airplanes with Garmin G1000, the GDC 74A air data computer compiles information from the
pitot/static system and various sensors. The GDC 74A gives pressure, altitude, airspeed, vertical
speed, and OAT information to the G1000 system. The GDC 74A communicates with the GIA 63
Integrated Avionics Units, GDU 1040 Control Display Units, and GRS 77 AHRS.
Maintenance practices give procedures for the removal and installation of the GDC 74A air data
computer. The unit is in the tailcone.

For troubleshooting procedures, refer to the Garmin G1000 Line Maintenance Manual.

GDC 74A Air Data Computer Removal/Installation
A.

Remove the Air Data Computer (Refer to Figure 201).
(1) Put the MASTER switch in the off position.
(2) Put the AVIONICS switch in the off position.
(3) Remove the aft seat. Refer to Chapter 25, Passenger Compartment - Maintenance Practices.
(4) Remove the baggage compartment closeout. Refer to Chapter 25, Interior Upholstery Maintenance Practices.
(5) Loosen the two thumb screws that attach the air data computer to the mounting rack.
(6) Disconnect the electrical connector.
(7) Disconnect the pitot/static lines.
CAUTION:

Do not let foreign object debris get In the air data computer. Foreign

object debris can cause a blockage and make the computer give
Incorrect Indications.

B.

(8) Put caps on the pitot/static lines and air data computer ports.
Install the Air Data Computer (Refer to Figure 201).
NOTE:

If a new air data computer is installed, the software must be loaded.

(1) Make sure the electrical connector and connector pins have no damage.
(a) Replace the electrical connector or connector pins if applicable. Refer to the Model 172
Wiring Diagram Manual and the Garmin G1000 Line Maintenance Manual.
(2) Remove the caps from the pitot/static lines and air date computer ports.
(3) Make sure the pitot/static lines and air data computer ports have no damage.
(a) Replace the pitot/static lines and/or air data computer ports if applicable. Refer to Chapter
34, Pitot/Static System - Maintenance Practices.
(4) Connect the electrical connector.
(5) Connect the pitot/static lines.
(6) Tighten the two thumb screws that attach the air data computer to the mounting rack.
(7) If a new unit is installed, load the software. Referto the Garmin G1000 Line Maintenance Manual.
(8) Do a pitot system leak test and a static system leak test. Refer to Chapter 34, Pitot/Static System
- Maintenance Practices.
(9) Do a check to make sure the air data computer operates correctly. Refer to the Garmin G1000
Line Maintenance Manual.
(10) Install the baggage compartment closeout. Refer to Chapter 25, Interior Upholstery Maintenance Practices.
(11) Install the aft seat. Refer to Chapter 25, Passenger Compartment - Maintenance Practices.

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MAINTENANCE MANUAL

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CORROSION ELIMINATION BY APPLICATION OF ORGANIC FILM

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Corrosion Identification
Figure 1 (Sheet 1)

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MAINTENANCE MANUAL
of the couple becomes the cathode of the galvanic cell. The degree of attack depends on the
relative activity of the two surfaces; the greater the difference in activity the more severe the
corrosion. Relative activity in descending order is as follows:
(a) Magnesium and its alloys.
(b) Aluminum alloys 1100, 3003, 5052, 6061, 220, 355, 356, cadmium and zinc.
(c) Aluminum alloys 2014, 2017, 2024, 7075 and 195.
(d) Iron, lead and their alloys (except stainless steel).
(e) Stainless steels, titanium, chromium, nickel, copper, and their alloys.
(f) Graphite (including dry film lubricants containing graphite).
(4) Intergranular Corrosion - Selective attack along the grain boundaries in metal alloys is referred to
as intergranular corrosion. It results from lack of uniformity in the alloy structure. It is particularly
characteristic of precipitation hardened alloys of aluminum and some stainless steels. Aluminum
extrusions and forgings in general may contain nonuniform areas, which in turn may result in
galvanic attack along the grain boundaries. When attack is well advanced, the metal may blister
or delaminate, which is referred to as 'exfoliation".
(5) Stress Corrosion - This results from the combined effect of static tensile stresses applied
to a surface over a period of time. In general, cracking susceptibility increases with stress,
particularly at stresses approaching the yield point, and with increasing temperature, exposure
time and concentration of corrosive ingredients in the surrounding environment. Examples
of parts which are susceptible to stress corrosion cracking are aluminum alloy bellcranks
employing pressed-in taper pins, landing gear shock struts with pipe thread-type grease fittings,
clevis joints and shrink fits.
(6) Corrosion Fatigue - This is a type of stress corrosion resulting from the cyclic stresses on a metal
in corrosive surroundings. Corrosion may start at the bottom of a shallow pit in the stressed area.
Once attack begins, the continuous flexing prevents repair of protective surface coating or oxide
films and additional corrosion takes place in the area of stress.
4.

Typical Corrosion Areas
A.

This section lists typical areas of the airplane which are susceptible to corrosion. These areas should
be carefully inspected at periodic intervals to detect corrosion as early as possible.
(1) Engine Exhaust Trail Areas.
(a) Gaps, seams and fairings on the lower right side of the fuselage, aft of the engine exhaust
stack, are typical areas where deposits may be trapped and not reached by normal cleaning
methods.
(b) Around rivet heads, skin laps and inspection covers on the airplane lower fuselage, aft of
the engine secondary exhaust stack, should be carefully cleaned and inspected.
(2) Battery Box and Battery Vent Opening.
(a) The battery, battery cover, battery box and adjacent areas, especially areas below
the battery box where battery electrolyte may have seeped, are particularly subject to
corrosive action. If spilled battery electrolyte is neutralized and cleaned up at the same
time of spillage, corrosion can be held to a minimum by using a weak boric acid solution
to neutralize the battery electrolyte (ni-cad battery) or baking soda solution to neutralize
the lead acid-type battery electrolyte. If boric acid or baking soda is not available, flood
the area with water.
(3) Steel Control Cables (including Stainless Steel).
(a) Checking for corrosion on control cables is normally accomplished during the preventative
maintenance check. During preventative maintenance, broken wires and wear of the
control cables are also checked.
(b) If the surface of the cable is corroded, carefully force the cable open by reverse twisting
and visually inspect the interior. Corrosion on the interior strands of the cable constitutes
failure and the cable must be replaced. If no internal corrosion is detected, remove loose
external rust and corrosion with a clean, dry, coarse-weave rag or fiber brush.
NOTE:

Do not use metallic wools or solvents to clean installed cables. Use of metallic
wool will embed dissimilar metal particles in the cables and create further
corrosion. Solvents will remove internal cable lubricant, allowing cable strands
to abrade and further corrode.
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After thorough cleaning of the exterior cable surface, apply a light coat of lubricant (VV-L800) to the external cable surface.
(4) Internal Fuel Tanks.
(a) The presence of soil contamination (a brown slimy substance) and pitting-type corrosion
may occur in the lower areas of the integral fuel tanks of certain airplanes. This condition
can cause a general degradation of some top coating and some depolymerization and
loosening of sealant materials in lower areas.
(b) The contaminants resemble normal aluminum corrosion products, including a considerable
quantity of iron. The brown, slimy deposits are microbial in nature. Examination of the
corrosion pits by metallurgical techniques indicate the presence of intergranular attacks.
(c)

5.

Corrosion Detection
A.

6.

Corrosion Defoliation. The primary means of corrosion detection is visual, but in situations where
visual inspection is not feasible, other techniques must be used. The use of liquid dye penetrant,
magnetic particle, X-ray and ultra-sonic devices can be used, but most of these sophisticated
techniques are intended for the detection of physical flaws within metal objects, rather than the
detection of corrosion.
(1) Visual Inspection. A visual check of the metal surface can reveal the signs of corrosive attack,
the most obvious of which is a corrosive deposit. Corrosion deposits of aluminum or magnesium
are generally a white or grayish-white powder, while the color of ferrous compounds varies from
red to dark reddish-brown.
(a) The indications of corrosive attack are small, localized discolorations of the metal surface.
Surfaces protected by paint or plating may only exhibit indications of more advanced
corrosive attack by the presence of blisters or bulges in the protective film. Bulges in lap
joints are indications of corrosive build-up which is well advanced.
(b) In many cases the inspection area is obscured by structural members, equipment
installations or, for other reasons, are awkward to check visually. In such cases, mirrors,
borescope or similar devices can be used to inspect the obscured areas. Any means
which allows a thorough inspection can be used. Magnifying glasses are valuable aids
for determining whether or not all corrosive products have been removed during clean up
operations.
(2) Liquid Dye Penetrant Inspection. Inspection for large stress-corrosion or corrosion fatigue cracks
on nonporous or nonferrous metals may be accomplished using dye penetrant processes. The
dye applied to a clean metallic surface will enter small openings or cracks by capillary action.
After the dye has an opportunity to be absorbed by any surface discontinuity, the excess dye is
removed and a developer is applied to the surface. The developer acts like a blotter and draws
the dye from cracks or fissures back to the surface, giving visible indication of any fault that is
present on the surface. The magnitude of the fault is indicated by the quantity of dye brought
back to the surface by the developer.

Corrosion Damage Limits
A.

Following cleaning and inspection of the corroded area, the actual extent of the damage may
be evaluated using the following general guidelines and good, sound maintenance judgement.
Determine the degree of corrosion damage (light, moderate, or severe) with a dial-type depth gage,
if accessibility permits. If the area is inaccessible, clay impressions, or any other means which will
give accurate results, should be used. In the event the corrosion damage is severe, contact Cessna
Propeller Aircraft Product Support for assistance.
(1) Light Corrosion - Characterized by discoloration or pitting to a depth of approximately 0.001 inch
maximum. This type of damage is normally removed by light hand-sanding or a minimum of
chemical treatment.
(2) Moderate Corrosion - Appears similar to light corrosion except there may be blistering or some
evidence of scaling or faking. Pitting depths may be as deep as 0.010 inch. This type of damage
is normally removed by extensive hand-sanding or mechanical sanding.
(3) Severe Corrosion - General appearance may be similar to moderate corrosion with severe
blistering exfoliation and scaling or flaking. Pitting depths may be as deep as 0.10 inch. This
type of damage is normally removed by extensive mechanical sanding or grinding (if not
complete part replacement).
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CHAPTER

DOORS

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LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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Temporary Revision
Number

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By

Date Removed

By

CESSNA AIRCRAFT COMPANY

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CONTENTS
DOORS - GENERAL .........

............................

........................

S cope......................................................................
Definition ...................................................................
CABIN DOORS - DESCRIPTION AND OPERATION ................................

Description .................................................................
Operation ............................ ...........
...........................
CABIN DOORS - MAINTENANCE PRACTICES ....................................
G en eral ....................................................................
Cabin Door Removal/Installation ....................
.........................
Cabin Door Weatherstrip Removal/Installation .........
........................
Cabin Door Latch Lock Removal/Installation ..............................
Cabin Door Latch Assembly Removal/Installation ..............................
Cabin Door Latch Cable Assembly Installation .................................
Cabin Door Lock Assembly Removal/Installation (on airplanes with standard locks)
Cabin Door Lock Assembly Removal/Installation (on airplanes with Medeco locks)
Cabin Door Lock Cam Assembly Removal/Installation (on airplanes with standard
locks)................
...
.................................................
Cabin Door Lock Cam Assembly Removal/Installation (on airplanes with Medeco
locks)...............
.........
......... ...................................
Cabin Door Adjustment/Test .........
.........
...............................
Cabin Door Latch Cable Assembly Rigging ....................................
Latch Assembly Adjustment/Test .............................................
BAGGAGE DOOR - MAINTENANCE PRACTICES.................................
G eneral ....................................................................
Baggage Door Removal/Installation. ..........................................
Baggage Door Weatherstrip Removal/Installation ..........
....................
Baggage Door Weatherstrip Inspection .......................................
Baggage Door Lock Assembly Removal/Installation (On airplanes with Medeco
lock).................................... .................................
Baggage Door Lock Cam Assembly Removal/Installation (On airplanes with
Medeco lock).............................................................

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DOORS - GENERAL

1.

Scope
A.

2.

This chapter provides maintenance information on doors.
instructions and rigging procedures.

Provided are removal/installation

Definition
A.

This chapter is divided into sections and subsections to assist maintenance personnel in locating
specific systems and information. The following is a brief description of each section. For locating
information within the chapter, refer to the Table of Contents at the beginning of the chapter.
(1) The cabin door section provides information on removal/installation and rigging of the doors.
(2) The baggage door section provides information on removal/installation of baggage door, seal
replacement and inspection.

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CABIN DOORS - DESCRIPTION AND OPERATION
1.

Description
A.

2.

A cabin door is installed on each side of the airplane. Each door has an outer sheet skin that is
chemically bonded to an inner pan assembly. Each door has a latch assembly, an inside handle, a
pair of external hinges, and a doorstop assembly.

Operation
A.

The cabin doors open by the inside or outside handle, that is connected to internal components.
(1) The cabin door latch is a two-part assembly latch base, external handle, spring-loaded latch bolt
and pull-bar assembly, and a spring-loaded catch pin assembly. The interior handle base plate
assembly is directly connected to the cabin door latch by an adjustable push rod assembly. This
push rod assembly has two clamps attached 180 degrees apart on the main rod. These clamps
operate a cable assembly that moves a cable pin from the top aft end of the cabin door into the
aft top door sill.
(2) The door latch exterior handle is extended when the cabin door is open. The handle is held in
position by the spring-loaded latch catch engaged with the latch bolt through the hole in the bolt.
The push rod assembly will move forward. The attached cable assembly will be retracted from
the top door sill with the cable pin in a recess in the pin guide. The interior handle will move
approximately 15 degrees aft of the vertical position.

B.

The cabin doors close and latch by the internal or external handle connected with internal components.
(1) The cabin door moves the catch pin over the actuator attached to the cover plate. The cover
plate is on the rear door post. The catch pin disengages the latch catch from the latch bolt as the
catch pin is moved forward. The latch handle extends and the pull-bar assembly compresses.
The latch handle is pulled in and the latch bolt is moved on the latch striker. The latch striker is
on the rear door post.
(2) The push rod assembly moves aft and moves the cable pin from the pin guide in the door into
the top aft door sill receptacle when the exterior handle is pushed flush with the fuselage skin.
The interior door handle has moved from approximately 15 degrees aft of the vertical position
to approximately 45 degrees forward of the vertical position. The interior handle pushed to the
horizontal position, flush with the armrest, will overcenter the door latch.

C.

The cabin doors have a key lock.
(1) The key lock turns and moves the pin into the exterior latch handle when the cabin door is closed
and the exterior latch handle is flush.
NOTE:

It is possible to lock the cabin door when the exterior handle is used and the push rod
assembly is not adjusted correctly. The rigging and adjustment procedures must be
used to correctly adjust the push rod.

,

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CABIN DOORS - MAINTENANCE PRACTICES
1.

I
2.

General
A.

The cabin door maintenance practices give procedures for the removal and installation of the cabin
doors, weatherstrip, locks, latches, handles, and cable assemblies.

B.

The cabin door maintenance practices also give procedures for the adjustment and test of the cabin
door, latch cable, and inside handle.

C.

An optional Medeco lock is installed on the cabin doors on some airplanes.

Cabin Door Removal/Installation
NOTE:

3.

4.

The removal and installation procedures given are for the pilot's door. The procedures for the
copilot's door are typical.

A.

Cabin Door Removal (Refer to Figure 201).
(1) Open the cabin door.
(2) Remove the nut, screw, and spacers from the stop fitting.
(3) Remove the nuts and screws that attach the hinges to the fuselage structure.
(4) Remove the cabin door from the airplane.

B.

Cabin Door Installation (Refer to Figure 201).
(1) Put the cabin door in position and attach the door with the screws and nuts.
(2) Install the screw, spacers, and nut on the stop fitting.
(3) Close and latch the cabin door.
(4) Make sure the cabin door is correctly adjusted. Refer to Cabin Door Adjustment/Test.

Cabin Door Weatherstrip Removal/Installation
A.

Cabin Door Weatherstrip Removal (Refer to Figure 201).
(1) Use a nonmetallic scraper to remove the weatherstrip and adhesive from the door assembly.
(2) Use solvent to remove all remaining adhesive from the door surface.

B.

Cabin Door Weatherstrip Installation (Refer to Figure 201).
(1) Cut the new weatherstrip to the correct length with the used weatherstrip as a template.
(2) Cut a small notch in the butt ends of the new weatherstrip to let water drain.
(3) Put the weatherstrip in position with the notches at the door low point.
(4) Apply a thin, smooth layer of EC-1300L, or equivalent adhesive to the two surfaces.
(5) Let the adhesive dry until it is tacky.
(6) Push the weatherstrip in position.
(7) Do not stretch the weatherstrip around the door corners.

Cabin Door Latch Lock Removal/Installation
A.

Cabin Door Latch
(1) Remove the
(2) Remove the
(3) Remove the

B.

Cabin Door Latch Lock Installation (Refer to Figure 201).
(1) Assemble the locking arm with the locking arm pin.
(a) Put one washer on each side of the locking arm.
(b) Swage the locking arm pin so there is minimum movement between the parts.
(c) Cut the unwanted material from the pin.
(2) Put the locking arm pin into the 0.125 inch (3.2 mm) diameter hole at the catch base assembly.
(3) Align the hole in the locking arm with the hole in the latch base assembly and install the pin.
(4) Put three washers between the cam and the locking arm.
(5) Attach the cam to the latch side of the locking arm.

Lock Removal (Refer to Figure 201).
cam from the latching side of the locking arm.
washers between the cam and the locking arm.
locking arm pin from the locking arm and the catch base assembly.

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A

3

I
TOP
HING

CLEVIS
PIN

DETAIL A
RIGHT SIDE SHOWN,
LEFT SIDE OPPOSITE
NUT
WASHER

DETAIL B
AIRPLANES WITH
STANDARD LOCKS

DETAIL C

0510T1007
A0511R1004
B0511R1005
C0511R1005

Cabin Door Installation
Figure 201 (Sheet 1)

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B230

PIN-

1

CABLE
ASSEMBLY

PIN
PUSHROD

SPACER

NU
CLAMP
BOLT

DETAIL

PULL
BAR

D

D0511R2003
E0511R2001

Cabin Door Installation
Figure 201 (Sheet 2)

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8231

AS NECESSARY
FOR GOOD SEAL
(TYPICAL ENTIRE
PERIMETER)

4.

WEATHERSTRIP

DOOR
STRUCTURE

VIEW A-A

WEATHERSTRIP

rnnn

0.25 INCH
NOTCH

VIEW B-B

AA0511T1003
F0511T1003

Cabin Door Installation
Figure 201 (Sheet 3)

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B6020

BEND THESE TABS TO MAKE SURE
THAT THEY DO NOT TOUCH THE
LATCH HOUSING

DD

VIEW C-C
AIRPLANES WITH MEDECO LOCK

COTTER PIN
WASHEF
LOCKING ARM

MACHINE SCREW

\

~// .'
, .'

SPACER

I_. A/~
?
l<
'_/,/
Xv

ANTI-ROTATIONAL
WASHER

SHELL

I

SERRATED WASHEER
RETAINING WA\SHER
CAM/PIN
/
_
.ASSEMBLY

'

j

I 0.5-0.75-INCH HEX NUT

\

LOCK TUMBLER
ASSEMBLY

VIEW D-D
CC1211T1038
DD1211T1038

LOCK SHOWN IN UNLOCKED POSITION
Cabin Door Installation
Figure 201 (Sheet 4)

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5.

Cabin Door Latch Assembly Removal/Installation
A.

Cabin Door Latch Assembly Removal (Refer to Figure 201).
(1) Remove the cabin door lock assembly. Refer to Cabin Door Lock Assembly Removal/
Installation.
(2)
Remove the rivets that attach the latch base to the door skin.
(3) Remove the screws that attach the latch to the door pan.
(4) Remove the pushrod and bolt.
(5) Pull the latch handle through the cutout in the door skin.
(6) Remove the latch assembly from the airplane.

B.

Cabin Door Latch Assembly Installation (Refer to Figure 201).
(1) Put the latch assembly in the closed position between the door pan and the door skin.
(2) Make sure the cable assembly is forward of the latch base attach plate, and inboard of latch
base cup.
(3) Extend the latch handle through the cutout in the door skin.
(4) Push the latch assembly aft so the bolt and pushrod extend through their related holes.
(5) Release the pushrod so the bolt is fully extended and the handle is flush.
(6) Attach the latch to the door pan with the screws through the base assembly and through the aft
flange of the door pan.
(7) Make sure the door skin dimension around the latch assembly is correct.

CAUTION: Do not make the holes oversize in the latch base.
Drill eleven 0.128 inch (3.25 mm) diameter holes that align with the latch base.
Make sure the cabin door latch cable assembly rigging and the cabin door inside handle rigging
is done before the latch base is attached to the skin. Refer to Cabin Door Latch Cable Assembly
Adjustment/Test and Cabin Door Inside Handle Rigging.
(10) Attach the latch base to the door skin with rivets.
(11) Install the cabin door lock assembly. Refer to Cabin Door Lock Assembly Removal/Installation.
(8)
(9)

6.

Cabin Door Latch Cable Assembly Installation
A.

Cabin Door Latch Cable Assembly Removal (Refer to Figure 201).
(1) Remove the screw and clamp that attach the cable assembly to the door.
(2) Remove the plug button.
(3) Remove the pin from the pin guide.
(4) Pull the pin end of the cable from the top of the door.
(5) Remove the nut and clamp from the opposite end of the cable casing.
(6) Remove the cable assembly from the door.

B.

Cabin Door Latch Cable Assembly Installation (Refer to Figure 201).
(1) Attach the clamp and nut one inch (25 mm) from the end of the cable casing on the pin end of
the cable assembly.
(2)
Put the pin end of the cable between the door pan and the door skin at the aft end of the door.
(3) Push the pin end of the cable to the top of the door.
(4)
Remove the plug button and align the pin of the cable with the pin guide.
(5) Put the pin through the pin guide.
(6) Align the clamp on the cable casing through the hole that is below the 0.875 inch (22.22 mm)
access hole.
(7) Install the screw.
(8) Make sure the cable operates freely.
(a) Add washers as required if the cable does not operate freely.
(9) Do the cabin door latch cable assembly rigging. Refer to Cabin Door Latch Cable Assembly
Rigging.

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7.

|

Cabin Door Lock Assembly Removal/Installation (on airplanes with standard locks)
A. Cabin Door Lock Assembly Removal (Refer to Figure 201).
(1) Remove the lower door accent panel and main door panel to get access to the cabin door lock
assembly. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(2) Remove the armrest door plugs, door panel insert, armrest, door handle, and cover plate from
the door to get access to the cabin door lock assembly.
(3) Remove the nut and washer.
(4) Remove the cabin door lock assembly.
B.

Cabin Door Lock Assembly Installation (Refer to Figure 201).
(1) Put the cabin door lock assembly in position.
(2) Install the washer and nut.
(3) Install the armrest door plugs, door panel insert, armrest, door handle and cover plate.
(4) Install the lower door accent panel and main door panel. Refer to Chapter 25, Interior Upholstery
- Maintenance Practices.

8.

9.

Cabin Door Lock Assembly Removal/Installation (on airplanes with Medeco locks)
A.

Cabin Door Lock Assembly Removal (Refer to Figure 201).
(1) Remove the lower door accent panel and main door panel to get access to the cabin door lock
assembly. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(2) Remove the armrest door plugs, door panel insert, armrest, door handle, and cover plate from
the door to get access to the cabin door lock assembly.
(3) Remove the cotter pin, washer, locking arm, and spacer from the lock assembly.
(4) Remove the hex nut and the anti-rotational washer that attach the lock tumbler assembly to the
door structure and the cam assembly.
(5) Remove the lock assembly from the door.

B.

Cabin Door Lock Assembly Installation (Refer to Figure 201).
(1) Put the cabin door lock assembly in position on the cabin door.
(2) Install the hex nut and the anti-rotational washer that attach the lock tumbler assembly to the
door structure and the cam assembly. Make sure that the anti-rotational washer is installed
under the hex nut.
(3) Torque the nut.
(4) Bend the applicable tab on the anti-rotational washer against the flat part of the nut.
(5) Install the spacer, locking arm, washer, and cotter pin that connect the lock assembly to the door
handle.
(6) Bend the applicable tabs on the cam-pin assembly to make sure that they do not touch the latch
housing.
(7) Install the armrest door plugs, door panel insert, armrest, door handle, and cover plate.
(8) Install the lower door accent panel and the main door panel. Refer to Chapter 25, Interior
Upholstery - Maintenance Practices.

Cabin Door Lock Cam Assembly Removal/Installation (on airplanes with standard locks)
A.

Cabin Door Lock Cam Assembly Removal (Refer to Figure 201).
(1) Remove the lower door accent panel and the main door panel to get access to the cabin door
lock cam assembly. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(2) Remove the armrest door plugs, door panel insert, armrest, door handle, and cover plate from
the door to get access to the cabin door lock cam assembly.
(3) Remove the cam stop screw from the cabin door lock cam assembly.
(4) Remove the cam assembly.

B.

Cabin Door Lock Cam Assembly Installation (Refer to Figure 201).
(1) Put the cam assembly in position.
Install the cam stop screw with Loctite 242.
(2)
(3) Install the armrest door plugs, door panel insert, armrest, door handle and cover plate.
(4) Install the lower door accent panel and main door panel. Refer to Chapter 25, Interior Upholstery
- Maintenance Practices.

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10.

11.

Cabin Door Lock Cam Assembly Removal/Installation (on airplanes with Medeco locks)
A.

Cabin Door Lock Cam Assembly Removal (Refer to Figure 201).
(1) Remove the lower door accent panel and main door panel to get access to the cabin door lock
cam assembly. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.
(2) Remove the armrest door plugs, door panel insert, armrest, door handle, and cover plate from
the door to get access to the cabin door lock cam assembly.
(3) Remove the machine screws, serrated washers, and retaining washer from the cabin door lock
cam assembly.
(4) Remove the cam assembly.

B.

Cabin Door Lock Cam Assembly Installation (Refer to Figure 201).
(1) Put the cam assembly in position.
(2) Install the machine screws, serrated washers, and retaining washer that attach the cam
assembly to the cabin door lock. Install the machine screws with Loctite 242.
(3) Install the armrest door plugs, door panel insert, armrest, door handle, and cover plate.
(4) Install the lower door accent panel and main door panel. Refer to Chapter 25, Interior Upholstery
- Maintenance Practices.

Cabin Door Adjustment/Test
A.

Adjust the new cabin doors.

CAUTION: Do not adjust the bonded door flange or the airplane structure with
force. Damage to the bonded areas and the structural components
can occur.
(1) Trim the door flange as required to get a gap between the door skin and fuselage skin of 0.09
inch (2.3 mm) or less.
B.

Adjust the cabin doors.
NOTE:

The cabin doors must be smooth with the fuselage skin.

(1) Use the slots at the door latch plate to adjust the latch assembly and the bolt engagement with
the rotary clutch on the door post.
12.

Cabin Door Latch Cable Assembly Rigging
A.

Do the Cabin Door Latch Cable Assembly Rigging (Refer to Figure 201).
(1) Pull the cable tight.
(2) Attach the clamp and the nut to the cable so it aligns with the 0.193 inch (4.9 mm) diameter hole
in the door pan.
(3) Make sure the door latch is open.
(4) Cut the casing of the cable assembly approximately two inches (50 mm) from the clamp bolt on
the push rod assembly.
(5) Put the core of the cable through the clamp.
(6) Pull the core of the cable through the clamp bolt so the pin extends approximately 0.125 inch
(3.2 mm) from the door pan contour.
(7) Cut the core of the cable approximately one inch (25 mm) forward of the push rod clamp.
(8) Attach the two nuts to the push rod clamp bolt.
(9) Make sure the latch operates freely.
(a) Remove the cable core from the clamp and operate the latch if the latch binds and will not
operate freely.
(b) Do a check of the cable for possible adjustments that will make the operation easier.
(10) Install the cover assembly and do another check of the cable operation.

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13.

Latch Assembly Adjustment/Test
A.

Do the adjustment of the latch assembly. (Refer to Figure 201).
(1) Make sure the cabin door is installed and fitted to the fuselage before the adjustment/test can
be done.
(2) Make sure the cabin door latch is in the OPEN position before the adjustment/test can be done.
(3) Make sure the door latch operates smoothly and freely.
(4) Make sure the bolt or pull bar are not filed, ground or sanded in any way.
NOTE:
(5)

Install shims to adjust the striker plate forward to give a minimal clearance between the bolt and
the striker plate.
NOTE:

(6)

A noise can be heard when the inside handle is pushed down. It is recommended
that the outside door handle be flush with the door skin, although the noise is heard.

This adjustment will make sure the pushrod will engage the latch catch. It will also
make sure the exterior handle will stay open until the door is closed again when the
door is opened from the outside.

Install shims as required, beneath the actuator on the cover assembly.
NOTE:

If the cabin door is too far forward for correct operation of the door latch, the latch
assembly pushrod will not let the bolt move.

Close the cabin door.
Make sure the exterior handle is flush with the door skin when the door is closed.
(a) Adjust the push-pull rod out, if the exterior handle is not flush with the door skin when the
door is closed.
1
Remove the screws and nuts that attach the base plate to the door.
2
Remove the smaller end of the push-pull rod and turn it 180 degrees.
3
Install the screws and nuts that attach the base plate.
(9) Do a check for slippage between the cable casing and clamps that attach the cable.
(10) Install the cotter pin in the clevis pin.
(7)
(8)

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MAINTENANCE MANUAL
BAGGAGE DOOR - MAINTENANCE PRACTICES
1.

2.

3.

4.

General
A.

A baggage door is installed on the left side of the airplane, aft of the cabin door. The baggage door
allows access into the baggage area and into the tailcone.

B.

A rubber weatherstrip is cemented around the edge of the baggage door. It seals the door to the
fuselage structure when the door is closed.

C.

An optional Medeco lock is installed on the baggage door on some airplanes.

Baggage Door Removal/Installation
A.

Baggage Door Removal (Refer to Figure 201).
(1) Open the baggage door.
(2) Disconnect the doorstop chain.
(3) Remove the upholstery panel from the door.
(4) Remove the bolts that attach the door to the hinges.

B.

Baggage Door Installation (Refer to Figure 201).
(1) Put the baggage door in position on the hinges and attach it with the bolts.
(2) Install the upholstery panel to the door.
(3) Connect the door stop chain.
(4) Close the baggage door and do a check for smooth operation.

Baggage Door Weatherstrip Removal/Installation
A.

Baggage Door Weatherstrip Removal (Refer to Figure 201)..
(1) Remove the baggage door.
(2) With a nonmetallic scraper, remove the seal and adhesive from the baggage door.
(3) Remove the adhesive residue and clean the door seal area with DeSoclean 110 Solvent.
(4) Install the baggage door.

B.

Baggage Door Weatherstrip Installation (Refer to Figure 201)..
(1) With the old seal or the door seal area of the baggage door as a pattern, measure and cut the
new seal to length.
(2) Apply a thin, even coat of RTV157 Adhesive around the circumference of the door seal area of
the baggage door.
(3) Make sure that you do not stretch the seal around the corners of the door.
(4) Push the new seal into the adhesive. Let the adhesive cure in accordance with the
manufacturer's instructions, and make sure that the seal is completely adhered to the door with
no gaps between the seal and the door.

Baggage Door Weatherstrip Inspection
A.

Do an Inspection of the Baggage Door Weatherstrip.
(1) Put a 4-inch by 11-inch piece of paper between the baggage doorframe and the baggage door.
Close the baggage door. Slowly pull on the paper to make sure that there is seal tension. Move
the paper around the perimeter of the door to do a test of the door seal tension.
(2) Remove the paper from the doorframe. Make sure that the baggage door is closed. Pour a
gallon of water over the door and tailcone doorframe. After the water no longer drips, open the
door and do an inspection for leaks.
(3) If any leaks are found, towel dry the upholstery with a clean, dry towel. Install the weatherstrip
again as necessary to make sure that there are no leaks around the seal area of the baggage
door.
(4) If necessary, apply U064158 Aerodynamic Filler Compound before you install the seal. Sand
and do a touch-up of the paint as necessary.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

8113

A

STRIKER
PLATE

DETAIL C

A
iGAGE
)R

b
BOLT
LATCH
AQCCQfMPI V

DOOR HINGE

LUJ'-r\

ASSEMBLY

A

DETAIL

B

DETAIL
AIRPLANES WITH STANDARD LOCK

0512T1004
A0512T1006
B0512T1005
C0512T1007

Baggage Door Installation
Figure 201 (Sheet 1)

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MODEL 172

MAINTENANCE MANUAL

B6019

B
DCKE

K

VIEW A-A
AIRPLANES WITH MEDECO LOCK

HEX NUT

LATCH ASSEMBLY

-1

LOCK TUMBLER ASSEMBLY

VIEW B-B
LOCK SHOWN IN LOCKED POSITION

AA0711T1048
BB071 1T1048

Baggage Door Installation
Figure 201 (Sheet 2)

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5.

6.

Baggage Door Lock Assembly Removal/Installation (On airplanes with Medeco lock)
A.

Baggage Door Lock Assembly Removal (Refer to Figure 201).
(1) Remove the baggage door panel to get access to the baggage door lock assembly. Refer to
Chapter 25, Interior Upholstery - Maintenance Practices.
(2) Remove the 0.75-inch hex nut and the anti-rotational washer that attach the lock tumbler
assembly to the door structure and the cam assembly.
(3) Remove the lock assembly from the door.

B.

Baggage Door Lock Assembly Installation (Refer to Figure 201).
(1) Put the baggage door lock assembly in position on the baggage door.
(2) Install the 0.75-inch hex nut and the anti-rotational washer that attach the lock tumbler assembly
to the door structure and the cam assembly. Make sure that the anti-rotational washer is installed
under the 0.75-inch hex nut.
(3) Torque the nut.
(4) Bend the applicable tab on the anti-rotational washer against the flat part of the nut.
(5) Install the baggage door panel to the baggage door. Refer to Chapter 25, Interior Upholstery Maintenance Practices.

Baggage Door Lock Cam Assembly Removal/Installation (On airplanes with Medeco lock)
A.

Baggage Door Lock Cam Assembly Removal (Refer to Figure 201).
(1) Remove the baggage door panel to get access to the baggage door lock assembly. Refer to
Chapter 25, Interior Upholstery - Maintenance Practices.
(2) Remove the hex nut and the serrated washer that attach the cam assembly to the baggage door
lock.
(3) Remove the cam assembly.

B.

Baggage Door Lock Cam Assembly Installation (Refer to Figure 201).
(1) Put the cam assembly in position.
(2) Install the hex nut and the serrated washer that attach the cam assembly to the baggage door
lock. Install the hex nut with Loctite 242.
(3) Install the baggage door panel to the baggage door. Refer to Chapter 25, Interior Upholstery Maintenance Practices.

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CHAPTER

STABILIZERS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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55-Record of Temporary Revisions
55-Contents

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Temporary Revision
Number

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Date Removed

By

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CONTENTS
STABILIZERS - GENERAL .......................................................

Scope .....................................................................
Definition ..................................................................
HORIZONTAL STABILIZER- MAINTENANCE PRACTICES..........................
General ....................................................................

Horizontal Stabilizer Removal/Installation .....................................
VERTICAL STABILIZER FIN - MAINTENANCE PRACTICES ........................

G eneral ....................................................................
Vertical Stabilizer Fin Removal/Installation..................................

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MODEL 172
MAINTENANCE MANUAL
STABILIZERS - GENERAL
1.

Scope
A.

2.

This chapter provides maintenance information on the horizontal and vertical stabilizer.

Definition
A.
B.

The section on horizontal stabilizer provides instructions for removal and installation of the horizontal
stabilizer.
The section on vertical stabilizer fin provides instructions for removal and installation on the vertical
stabilizer fin.

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MODEL 172
MAINTENANCE MANUAL

HORIZONTAL STABILIZER - MAINTENANCE PRACTICES
1.

2.

General
A.

The horizontal stabilizer is primarily of all-metal construction, consisting of ribs and spars covered
with skin. A formed metal leading edge is riveted to the assembly to complete the structure. The
elevator trim tab actuator is contained within the horizontal stabilizer. The underside of the stabilizer
contains a covered opening which provides access to the actuator. Hinges are located on the rear
spar assembly to support the elevators.

B.

This section provides removal and installation instructions for the horizontal stabilizer.

Horizontal Stabilizer Removal/Installation
A.

Remove Horizontal Stabilizer (Refer to Figure 201).
(1) Remove elevators. Refer to Chapter 27, Elevator Control System- Maintenance Practices.
(2) Remove rudder. Refer to Chapter 27, Rudder Control System - Maintenance Practices.
(3) Remove vertical stabilizer. Refer to Vertical Stabilizer - Maintenance Practices.
(4) Disconnect elevator trim control cables at clevis and turnbuckle inside tailcone.
(5) Remove pulleys which route the aft cables into horizontal stabilizer, and pull cables out of
tailcone.
(6) Remove bolts securing horizontal stabilizer to fuselage.
NOTE:
(7)

B.

Note the order in which any spacers or shims are removed for reinstallation.

Remove horizontal stabilizer.

Install Horizontal Stabilizer (Refer to Figure 201).
(1) Install horizontal stabilizer to fuselage using bolts.
NOTE:
(2)
(3)
(4)
(5)
(6)

Reinstall any spacers and shims in the exact order in which they were removed.

Reroute cables into tailcone and install pulleys.
Reconnect elevator trim control cables at clevis and turnbuckle inside tailcone.
Install vertical stabilizer. Refer to Vertical Stabilizer - Maintenance Practices.
Install rudder. Refer to Chapter 27, Rudder Control System - Maintenance Practices.
Install elevators. Refer to Chapter 27, Elevator Control System - Maintenance Practices.

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MAINTENANCE MANUAL

B232

A

UPPER RIGHT
FAIRING

B

UPPER LEFT
FAIRING

HORIZONTAL
LIZER

FORWARD RIGHT
FAIRING

,
FORWARD LEFT
FAIRING

STABILIZER
TIP

OUTBOARD
ELEVATOR
HINGE

BRACKET

DETAIL

A

BUSHING

DETAIL C
INBOARD
ELEVATOR
HINGE

DETAIL B

BUSHING
0532T1004
A0532T1003
B0532T1003
C0532T1002

Horizontal Stabilizer Installation
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
VERTICAL STABILIZER FIN - MAINTENANCE PRACTICES
1.

2.

General
A.

The vertical stabilizer fin is of metal construction, consisting of ribs and spars covered with aluminum
skin. The trailing edge of the fin contains three hinges used to attach the rudder.

B.

Maintenance practices consist of removal and installation of the vertical stabilizer fin.

Vertical Stabilizer Fin Removal/Installation
A.

Remove Vertical Stabilizer Fin (Refer to Figure 201).
(1) Remove rudder. Refer to Chapter 27, Rudder Control System - Maintenance Practices.
(2) Remove upper left and upper right fairings.
(3) Disconnect all electrical, navigation light, and antenna leads from base of fin area.
(4) Remove screws attaching dorsal to fin.
(5) Disconnect elevator cable from elevator bellcrank.
(6) Remove bolts and shims (if installed) attaching fin rear spar to fuselage fitting.
(7) Remove upper elevator stop bolt.
(8) Remove bolts attaching fin front spar to fuselage bulkhead and remove fin from fuselage.

B.

Install Vertical Stabilizer Fin (Refer to Figure 201).
(1) Place fin on fuselage and secure front spar of fin to fuselage.
(2) Install upper elevator stop bolt.
(3) Attach fin rear spar to fuselage fitting using shims (if required) and bolts
NOTE:

If new fin is being installed, gap between the fin rear spar and the fuselage fitting
should not exceed 0.030 inch. If gap exceeds this dimension, it is permissible to use
one shim per bolt to obtain desired clearance. Use the following chart for shim part
numbers:

Gap between fitting and spar

Shim Thickness

Shim Part Number

0.030 to 0.050 inch

0.020 inch

0531115-1

0.050 to 0.070 inch

0.040 inch

0531115-2

(4)
(5)
(6)
(7)

(8)

Connect elevator cable to elevator bellcrank.
Secure dorsal to fin using screws.
Reconnect all electrical, navigation, and antenna leads.
Install upper left and upper right fairings.
Install rudder. Refer to Chapter 27, Rudder Control System - Maintenance Practices.

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MAINTENANCE MANUAL
.
.B112

NOTE:

UPPER
RUDDER
IINGE

FAIRING AND DORSAL
FIN ARE RIVETED TO
FUSELAGE.

FIN TIP

DORSAL

DETAIL A

CENTER

FAIRING

FIN
ASSEMBLY

NUTPLATES
UPPER
RIGHT
FAIRING

AILB
LOWER
RUDDER
HINGE
SHIM

WASHER
FUSELAGE

FAIRING

DETAIL C
0560T1012
A0560T1006
B0560T1007
C0560T1008

Vertical Stabilizer Fin Installation
Figure 201 (Sheet 1)

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CHAPTER

WINDOWS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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56 - LIST OF EFFECTIVE PAGES
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Jan 2/2006

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
WINDOWS - GENERAL ..........................................................

Scope......................................................................
Tools, Equipment and Materials ..............................................
Definition ...................................................................
WINDSHIELDS AND WINDOWS - DESCRIPTION AND OPERATION ................
General ....................................................................
Tools, Equipment and Materials ..............................................
Cleaning Instructions........................................................
Windshield and Window Preventive Maintenance ..............................
Windshield and Window Installation Techniques ...............................
Windshield Rain Repellent...................................................
WINDSHIELD - MAINTENANCE PRACTICES......................................
General ....................................................................
Windshield Removal/Installation..............................................
Temporary Repairs ..........................................................
CABIN WINDOWS - MAINTENANCE PRACTICES .................................
G en era l ....................................................................
Rear Window Removal/Installation............................................
Side Window Removal/Installation ............................................
CABIN DOOR WINDOWS - MAINTENANCE PRACTICES ..........................
General ....................................................................
Cabin Door Window Removal/Installation .....................................

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
WINDOWS - GENERAL
1.

Scope
A.

2.

This chapter provides information on windows used throughout the airplane.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes may be used for the following listed items:

NAME

NUMBER

Mild Soap or
Detergent (hand
dishwashing type
without abrasives)

MANUFACTURER

USE

Commercially Available

To clean windshields and
windows.

Aliphatic Naphtha

Type II
Federal
Specification
TT-N-95

Commercially Available

To remove deposits
from windshields and
windows.

Novus

Number 1

Commercially Available

To clean acrylic
windshields and
windows.

Novus

Number 2

Commercially Available

To remove minor
surface scratches in
acrylic windshields and
windows.

Novus

Number 3

Commercially Available

To remove heavy
scratches and abrasions
in acrylic windshields and
windows.

Mirror Glaze

MGH-7

Meguiars Mirror Bright Polish
210 N First Ave.
Arcadia, CA 91006

To clean and polish
acrylic windshields and
windows.

Commercially Available

To apply and remove wax
and polish.

Soft cloth, such
as: Cotton flannel
or cotton terry
cloth
Windshield
sealant tape

U000927S

Available from
Cessna Parts Distribution
Cessna Aircraft Company
Department 701
5800 E. Pawnee Rd.
Wichita, KS 67218-5590

To seal windshield.

Repcon rain
repellent

6850-00-1395297

Unelko Corporation
7428 East Karen Drive
Scottsdale, Arizona 85260

To repell rain from
windshield.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

3.

Definition
A.

This chapter is divided into sections and subsections to assist maintenance personnel in locating
specific systems and information. The following is a brief description of each section. For locating
information within the chapter, refer to the Table of Contents at the beginning of the chapter.
(1) The section on windshields and windows provides installation notes and precautions applicable
to the entire chapter.
(2) The section on flight compartment windows provides maintenance instructions for repair and
replacement of the windshield.
(3) The section on cabin windows provides maintenance instructions for the cabin side and cabin
rear windows.
(4) The section on door windows provides maintenance instructions for openable windows located
in the cabin doors.

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MAINTENANCE MANUAL
WINDSHIELDS AND WINDOWS - DESCRIPTION AND OPERATION
1.

General
A.

2.

Tools, Equipment and Materials
A.

3.

This section provides instructions and tips for cleaning and installing windshields and windows used
in the airplane.

For a list of required tools, equipment and materials, refer to Windows - General.

Cleaning Instructions

CAUTION: WINDSHIELDS
AND
WINDOWS
(ACRYLIC-FACED)
ARE
EASILY DAMAGED BY IMPROPER HANDLING AND CLEANING
TECHNIQUES.
CAUTION: DO NOT USE METHANOL, DENATURED ALCOHOL, GASOLINE,
BENZENE, XYLENE, METHYL N-PROPYL KETONE, ACETONE,
CARBON TETRACHLORIDE, LACQUER THINNERS, COMMERCIAL
OR HOUSEHOLD WINDOW CLEANING SPRAYS ON WINDSHIELDS
OR WINDOWS.
A.

Instructions For Cleaning.
(1) Place airplane inside hangar or in shaded area and allow to cool from heat of suns direct rays.
(2) Using clean (preferably running) water, flood the surface. Use bare hands with no jewelry to feel
and dislodge any dirt or abrasive materials.
(3) Using a mild soap or detergent (such as a dishwashing liquid) in water, wash the surface. Again
use only the bare hand to provide rubbing force. (A clean cloth may be used to transfer the soap
solution to the surface, but extreme care must be exercised to prevent scratching the surface.)
(4) When contaminants on acrylic windshields and windows cannot be removed by a mild detergent,
Type II aliphatic naphtha, applied with a soft clean cloth, may be used as a cleaning solvent. Be
sure to frequently refold cloth to avoid redepositing contaminants and/or scratching windshield
with any abrasive particles.
(5) Rinse surface thoroughly with clean fresh water and dry with a clean cloth.
(6) Hard polishing wax should be applied to acrylic surfaces. (The wax has an index of refraction
nearly the same as transparent acrylic and will tend to mask any shallow scratches on the
windshield surface).
(7) Acrylic surfaces may be polished using a polish meeting Federal Specification P-P-560 applied
per the manufacturers instructions.
NOTE:

4.

When applying and removing wax and polish, use a clean, soft cloth, such as cotton
or cotton flannel.

Windshield and Window Preventive Maintenance
NOTE:
A.

Utilization of the following techniques will help minimize windshield and window crazing.

General Notes and Techniques For Acrylic Windshields.
(1) Keep all surfaces of windshields and windows clean.
(2) If desired, wax acrylic surfaces.
(3) Carefully cover all surfaces during any painting, powerplant cleaning or other procedure that
calls for use of any type of solvents or chemicals.
(4) Do not park or store airplane where it might be subjected to direct contact with or vapors from:
methanol, denatured alcohol, gasoline, benzene, xylene, methyl n-propyl ketone, acetone,
carbon tetrachloride, lacquer thinners, commercial or household window cleaning sprays, paint
strippers, or other types of solvents.

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(5) Do not leave sun visors up against windshield when not in use. The reflected heat from these
items causes elevated temperatures on the windshield. If solar screens are installed on the
inside of the airplane, make sure they are the silver appearing, reflective type.
(6) Do not use a power drill motor or other powered device to clean, polish, or wax surfaces.
5.

Windshield and Window Installation Techniques
A.

Installation Techniques.
(1) Special drills must be used when drilling holes in acrylic. Standard drills will cause the hole to
be oversized, distorted, or excessively chipped.
(2) Whenever possible, a coolant such as a plastic drilling wax should be used to lubricate the drill
bit.
(3) Drilled holes should be smooth with a finish of 125 rms (root mean square).
(4) The feed and speed of the drill is critical. Refer to Table 1 for thickness verses drill speed
information.

Table 1. Material Thickness vs. Drill Speed

Thickness (in inches)

Drill Speed (RPM)

0.062 to 0.1875

1500 to 4500

0.250 to 0.375

1500 to 2000

0.4375

1000 to 1500

0.500

500 to 1000

0.750

500 to 800

1.00

500

(5) In addition to feed and speed of the drill bit, the tip configuration is of special importance when
drilling through acrylic windows and windshields. Tip configuration varies with hole depth, and
the following information applies when drilling through acrylic:
(a) Shallow Holes - When hole depth to hole diameter ratio is less than 1.5 to 1, the drill shall
have an included tip angle of 55 degrees to 60 degrees and a lip clearance angle of 15
degrees to 20 degrees.
(b) Medium Deep Holes - When hole depth to hole diameter ratio is from 1.5 to 1 up to 3 to 1,
the drill shall have an included tip angle of 60 degrees to 140 degrees and a lip clearance
angle of 15 degrees to 20 degrees.
(c) Deep Holes - when hole depth of hole diameter ratio is greater than 3.0 to 1,the drill shall
have an included tip angle of 140 degrees and a lip clearance of 12 degrees to 15 degrees.
(6) Parts which must have holes drilled shall be backed up with a drill fixture. Holes may be drilled
through the part from one side. However, less chipping around holes will occur if holes are drilled
by drilling the holes from both sides. This is accomplished by using a drill with an acrylic backup
piece on the opposite side. Remove the drill from the hole and switch the backup plate and finish
drilling from the opposite side.
6.

Windshield Rain Repellent
A.

Repcon is a rain repellent and surface conditioner that may be used to increase the natural cleaning
of the windshield during rain. Apply in accordance with manufacturers instructions.

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MAINTENANCE MANUAL
WINDSHIELD - MAINTENANCE PRACTICES

1.

General
A.

2.

This section provides instructions for removal and installation of the window as well as repair
techniques applicable to acrylic windshields and windows.

Windshield Removal/Installation
A.

Remove Windshield (Refer to Figure 201).
(1) Remove wing fairings.
(2) Remove air vent tubes.
(3) Drill out rivets securing front retainer strip.
CAUTION:

B.

3.

IF WINDSHIELD IS TO BE REINSTALLED,
PROTECT WINDSHIELD DURING REMOVAL.

BE

SURE TO

(4) Pull windshield straight forward, out of side and top retainers. Remove top retainer if necessary.
(5) Clean sealer from inner sidewalls and bottom of retainers.
Install Windshield (Refer to Figure 201).
(1) If windshield is to be reinstalled, clean off old sealer and felt, then install new felt around edges
of windshield.
(2) If new windshield is to be installed, remove protective cover and clean.
(3) Apply new felt to edges of windshield.
(4) Apply windshield sealant tape along the sides and bottom of felt. Refer to Windows - General
for a list of sealant tape.
(5) Position the bottom edge of windshield against deck skin.
(6) Using a piece of bent sheet metal (8 inches wide x length of top edge of windshield) placed
under top edge of upper retainer, bow windshield and guide top edge of windshield into upper
retainer using bent sheet metal in a shoe horn effect.
(7) Secure front retainer strip using rivets.
(8) Install air vent tube.
(9) Install wing fairings.

Temporary Repairs
A.

Temporary repairs to windshields and windows can be accomplished using techniques illustrated and
described in the Single Engine Structural Repair Manual, Chapter 56, Plastic Window Surface Repair.

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MAINTENANCE MANUAL

B1

OUTER

FELT

INNER
RETAINER

DETAIL A

jOUTER
RETAINER

FELT
SEAL

RETAINER

DETAILD

DETAIL

D

0510T1007
A0511T3002
B0511T3002
C0511T3002
D0511T3002

RETAINER

DETAIL C
Windshield Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
CABIN WINDOWS - MAINTENANCE PRACTICES
1.

General
A.

2.

3.

The airplane is equipped with two side windows and a rear window, all located in the rear cabin area.
Maintenance practices are limited to removal and installation of the windows. For instructions on
temporary repair, refer to Windshield - Maintenance Practices.

Rear Window Removal/Installation
A.

Remove Rear Window (Refer to Figure 201).
(1) Remove external center strip retainer.
(2) Remove upholstery as necessary to expose retainer strips inside cabin. Refer to Chapter 25,
Interior Upholstery - Maintenance Practices.
(3) Drill out rivets as necessary to remove outer retainer strip along aft edge of window.
(4) Remove window by lifting aft edge and pulling window aft. If difficulty is encountered, rivets
securing retainer strips inside cabin may also be drilled out and retainer strips loosened or
removed.

B.

Install Rear Window (Refer to Figure 201).
(1) If old window is being reinstalled, remove all traces of old sealant from window.
(2) Clean out channels and retainers to remove all traces of old sealant.
(3) Check fit and carefully file or grind away excess plastic.
(4) Apply felt strip and sealant to all edges of window to prevent leaks.
(5) Reinstall rear window to airplane and secure using retainer strips and rivets.
(6) Install upholstery. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.

Side Window Removal/nstallation
A. Remove Side Window (Refer to Figure 201 ).
(1) Remove upholstery as required to gain access to retainer strips inside cabin. Refer to Chapter
25, Interior Upholstery - Maintenance Practices.
(2) Drill out rivets securing retainer strips to airplane.
B. Install Side Window (Refer to Figure 201).
(1) If old window is being reinstalled, remove all traces of old sealant from window.
(2) Clean out channels and retainers to remove all traces of old sealant.
(3) Apply felt strip and sealant to all edges of window to prevent leaks.
(4) Reinstall retainer strips using rivets.
(5) Reinstall upholstery. Refer to Chapter 25, Interior Upholstery - Maintenance Practices.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1784

IAREAR
1 KI r%/r'%AI

SIDE
WINDOW

0512T4001

Cabin Windows Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
CABIN DOOR WINDOWS - MAINTENANCE PRACTICES
1.

General
A.

2.

This maintenance practices section consists of removal and installation of the hinged windows located
in each door. For instructions on temporary repair to the cabin door windows, refer to Windshield Maintenance Practices.

Cabin Door Window Removal/Installation
A.

Remove Cabin Door Window (Refer to Figure 201).
(1) Disconnect arm from window assembly.
(2) Remove hinge pins from hinge.

B.

Install Cabin Door Window (Refer to Figure 201).
(1) Position window assembly to door.
(2) Secure window assembly to hinge using hinge pin.

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MODEL 172

MAINTENANCE MANUAL

B1

LATCH
BRACKET

WINDOW
ASSEMBLY

DETAIL B

HINGE
ASSEMBLY

ARM

DETAIL

A
0510T1007
A0511T3001
B0511T1002

Cabin Door Window Installation
Figure 201 (Sheet 1)

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CHAPTER

WINGS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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57-List of Effective Pages
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Number

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By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
W INGS - GENERAL..........

..................................................

S cope......................................................................
Tools, Equipment and Materials ..............................................
Definition ...................................................................
WINGS AND WING STRUTS - MAINTENANCE PRACTICES........................
Description and Operation ...................................................
Wing and Strut Removal/Installation ..........................................
Adjustment (Correcting Wing Heavy Conditions) ...............................
Strut Damage and Repair Criteria ............................................
Wing Tip Removal/Installation ................................................

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
WINGS - GENERAL
1.

Scope
A.

2.

This chapter provides instructions on wing removal and installation. Information and repair procedures
beyond the scope of this chapter can be found in the Single Engine 1996 and On Structural Repair
Manual.

Tools, Equipment and Materials
NOTE:

Equivalent substitutes may be used for the following listed items:

NAME

NUMBER

MANUFACTURER

USE

Grease

MIL-G-21164

E/M Corporation
Box 2200
Highway 52 N.W.
West Lafayette, IN 47906

To lubricate wing attach
fittings and bolts upon
reinstallation.

3.

Definition
A.

This chapter contains a single section on wing removal, installation and adjustment.

© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
WINGS AND WING STRUTS - MAINTENANCE PRACTICES
1.

2.

Description and Operation
A.

Each metal wing is a strut braced type, with two main spars and suitable ribs for the attachment of the
skin. Skin panels are riveted to ribs, spars and stringers to complete the structure. An all metal, piano
hinged aileron, flap and detachable wing tip are mounted on each wing assembly. Each wing also
incorporates an integral fuel bay located between the two spars at the inboard portion of the wing.
Each wing is supported in position by a single lift strut which consists of a streamlined tube riveted to
two end fittings for attachment at the wing and at the fuselage.

B.

For a skeletal view of the wing assembly, refer to Chapter 6, Airplane Stations - Description and
Operation, Figure 2.

Wing and Strut Removal/Installation
A.

Remove Wing and Strut (Refer to Figure 201).
NOTE:

Wings are most easily removed if four people are available to handle the wing. Otherwise,
the wing should be supported with a sling or maintenance stand when the fasteners are
loosened.

(1) Remove fasteners from fairings at wing/fuselage intersections.
(2) Remove inspection plates as required to allow for disconnection of all electrical, mechanical and
fuel connections.
(3) Drain fuel from wing.
(4) Disconnect electrical wires at wing root disconnects.
(5) Disconnect fuel lines at wing root.
(6) On left wing, disconnect pitot line.
(7) Disconnect fresh air distribution duct at wing root.
(8) Loosen and disconnect aileron cables at aileron bellcrank.
(9) Disconnect flap cables at turnbuckle above cabin headliner, and pull cables into wing root area.
NOTE:

To ease rerouting of cables, a guide wire may be attached to each cable before it
is pulled free from the wing. Cable may then be disconnected from the guide wire.
Leave the guide wire routed through the wing; it will be reattached to the cable during
installation and used to pull the cable into place.

(10) Remove screws from strut fairings and slide fairings toward center of strut.
(11) Support wing at outboard end. Remove strut-to-wing attach bolt and strut-to-fuselage attach
bolt.
(12) Remove strut from between wing and fuselage.
NOTE:

Tape flaps in the streamlined position during wing removal. This will prevent flap
movement during handling.

(13) Mark position of wing attachment eccentric bushings in relationship to fittings. These bushings
are used to rig out wing heaviness, and if bushings are not marked, wings may require
readjustment at installation.
(14) Remove nuts, washers, bushings and bolts attaching wing spars to fuselage.
NOTE:

It may be necessary to rock the wings slightly and/or to use a long drift punch to
remove attaching bolts.

(15) Remove wing and lay on padded stand.

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CESSNA AIRCRAFT COMPANY

MODE

172

MAINTENANCE MANUAL

B234

WASHERS

NUT

LOWER
REAR
FAIRING

ECCENTRIC
BUSHINGS

A

FAIRING

DETAIL A
WING
FLAP

AILERC

FUEL
FILLER
CAP
COURTESY
LIGHT

G TIP

WASHERS

NAVIGATION AND
STROBE LIGHTS

BOLT
NUT

DETAIL

B

0520T2001
A0520T1003
B0520T1002

Wing Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B233

NOTE:

LUBRICATE BOLT AND HOLE
PRIOR TO INSTALLATION

A
TIE-DOWN
RING

SCREW

LOWER
FAIRING
FAIRING

SPACER

WING STRUT

WING
WING STRUT
STRUT

ATTACHMENT

RING
FUSEL
ATTAC
FITTING

DETAIL
DETAIL B

A
0520T1006
0520T 1006
0520T1006
A0520T1006
B0520T1006

BOLT
(NOTE)
Wing Installation
Figure 201 (Sheet 2)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
B.

Install Wing and Strut (Refer to Figure 201).
(1) Hold wing in position and install bolts, bushings, washers and nuts attaching wing spars to
fuselage fittings. Ensure eccentric bushings are positioned as marked.
NOTE:

Lightly lubricate wing attach bolts and holes with MIL-G-21164 grease before
installing bolts.

CAUTION: DO NOT LUBRICATE THE THREADS OF THE BOLTS.
(2) Torque front wing spar bolts from 300 to 690 inch pounds. Torque rear wing spar bolts from 300
to 500 inch pounds.
(3) Position upper and lower strut fairings on strut.
NOTE:

Wrap wing strut using 3MY8671 polyurethane tape (1 inch wide) centered at point
where cuff terminates.

(4) Install bolts, spacers and nuts to secure upper and lower ends of wing strut to wing and fuselage
fittings. Torque nuts to 480 to 690 inch-pounds.
NOTE:

Lightly lubricate bolts and holes with MIL-G-21164 grease before installing bolts.

CAUTION: DO NOT LUBRICATE THE THREADS OF THE BOLTS.
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
3.

Route flap and aileron cables, using guide wires.
Reconnect all fuel, electrical and mechanical connections removed above.
Rig flap system. Refer to Chapter 27, Flap Control System - Maintenance Practices.
Rig aileron systems. Refer to Chapter 27, Aileron Control System - Maintenance Practices.
Refuel wing tank.
Check operation of all mechanical, electrical and fuel systems.
Install wing root fairings.
Install all removed access/inspection plates and upholstery.

Adjustment (Correcting Wing Heavy Conditions)
NOTE:
A.

If considerable control wheel pressure is required to keep the wings level in normal flight, a "wing
heavy" condition exists and can be corrected by the following procedure.

Adjustment Procedures (Refer to Figure 201, Detail A).
(1) Remove wing fairing strip on the wing heavy side of the airplane.

CAUTION: ENSURE THE ECCENTRIC BUSHINGS ARE ROTATED
SIMULTANEOUSLY. ROTATING THEM SEPARATELY WILL
DESTROY THE ALIGNMENT BETWEEN THE OFF-CENTER
BOLT HOLES IN THE BUSHINGS, THUS EXERTING A
SHEARING FORCE ON THE BOLT, WITH POSSIBLE DAMAGE
TO THE HOLE INTHE WING SPAR.
NOTE:

The eccentric cams should only be adjusted after other flight control systems have
been adjusted and rigged.

(2) Loosen nut and rotate eccentric bushings simultaneously until the bushings are positioned with
the thick side of the eccentrics up. This will lower the trailing edge of the wing, and decrease
wing heaviness by increasing angle of incidence of the wing.
(3) Torque the nut from 300 to 500 inch pounds and reinstall fairing strip.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
(4)

(5)
4.

Strut Damage and Repair Criteria
A.

5.

Test fly the airplane. If the wing heavy condition still exists, remove fairing strip on the lighter
wing, loosen nut and rotate bushing simultaneously until the bushings are positioned with the
thick side of the eccentrics down. This will raise the trailing edge of the wing, thus increasing
wing heaviness to balance heaviness in the opposite wing.
Torque nut from 300 to 500 inch pounds, install fairing strip and repeat flight test.

For wing strut damage and repair criteria, refer to the Single Engine Structural Repair Manual Chapter
57, Wing Damage Classification.

Wing Tip Removal/Installation
A.

Remove Wing Tip (Refer to Figure 202).
(1) Remove screws securing wing tip to wing.
(2) Remove screw securing strobe light and navigation light ground straps to power supply.
(3) Disconnect navigation light electrical connector.
(4) Disconnect strobe light electrical connector.
(5) Remove wing tip from wing.

B.

Install Wing Tip (Refer to Figure 202).
(1) Connect strobe light electrical connector, and connect navigation light electrical connector.
(2) Slide the wing tip into position over the wing tip rib ensuring the existing holes in the wing tip
align with the attach holes in the wing skin/rib nutplates.
(3) Fabricate a curved spacer from phenolic or aluminum which is 0.01 to 0.03 inch thick X 1.0 inch
X 2.0 inches which matches the contour of the leading edge.
(4) Insert the spacer at the leading edge of the wing between the skin and the inside contour of the
wing tip.
(5) Secure wing tip to wing using screws starting at the aft of the tip and working forward.
(6) When all screws are secure, remove the spacer to leave a gap of 0.01 inch to 0.03 inch between
the skin and the inside contour of the wing tip.

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MODEL 172
MAINTENANCE MANUAL

B110

P

A

INCH

r

WING ROOT
WING

TIP

-w A-A

SCREW

GAP BETWEEN WING TIP
AND FRONT OF WING
LEADING EGDE
0.01 INCH MINIMUM
0.03 INCH MAXIMUM

WING LEADING EDGE

DETAIL

A
0510T1007
A0510T1001
A-A0523T1001

Wing Tip Installation
Figure 202 (Sheet 1)

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CHAPTER

PROPELLERS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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Jul 1/2007

61 -Title
61 -List of Effective Pages
61 -Record of Temporary Revisions
61 -Table of Contents

61
©Cessna Aircraft Company

-

LIST OF EFFECTIVE PAGES

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Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
PROPELLERS - GENERAL ............................
Scope....................................
Definition ..................................
PROPELLER - MAINTENANCE PRACTICES....................
Description and Operation ..........................
Propeller and Spinner Removal/installation...................

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
PROPELLERS - GENERAL
1.

Scope
A.

2.

This chapter provides instructions on propeller and spinner.

Definition
A.

This chapter contains a single section on removal and installation of the propeller and spinner.

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MODEL 172

MAINTENANCE MANUAL
PROPELLER

-

MAINTENANCE PRACTICES

1.Description and Operation
propeller. Maintenance practices consist
A. The airplane is equipped with a two bladed, fixed pitch metal beyond the scope of this section, refer
of propeller/spinner removal and installation. For information
to the applicable McCauley Service Manual.
2.

Propeller and Spinner Remnoval/Installation
A. Remove the Propeller and Spinner (Refer to Figure 201).

Ensure
the propeller.
WARNING: Exercise care when working with before
turning propeller.
magneto switch is in the off position
- Maintenance Practices.
Remove the cowling and nosecap. Refer to Chapter 71, Cowling
Remove the spinner.
bulkheads.
aft
Remove screws securing the spinner to the forward and bolts.
mounting
propeller
Cut and discard safety wire from the
aft bulkhead and spacer from
Remove the mounting bolts, forward bulkhead, propeller,
crankshaft.
when removed.
A dowel pin holds the propeller, aft bulkhead and spacer together
NOTE:
inspected, refer to ASTM E-1414 or
(5) The propeller mounting bolts must be magnetic particle
at every overhaul. The propeller
replaced
or
liquid penetrant inspected, refer to ASTM E-1 417,
in a blade strike.
involved
is
propeller
the
mounting bolts must be replaced when
propeller.
the
from
bulkhead
aft
the
and
(6) Remove the spacer
bags placed as close to the hub
(a) Support the propeller by setting it between two sand filled
for the spacer and aft
clearance
of
inches
(2)
two
as possible with the spacer down. Allow
to separate from the hub.
~ ~~~~~~bulkhead
long. Insert rod into propeller hub
(b) Select a rod of proper diameter and is six (6) inches
in a alternating pattern to free the
dowels
dowel pin holes. Using a hammer, lightly tap
remain in the spacer.
will
dowels
The
hub.
spacer and bulkhead from propeller
remove dowels from spacer
hub,
propeller
the
in
installed
were
(c) If the tapered end of dowels
lightly tap dowels in
hammer,
a
by inserting the rod into dowel pin holes in spacer. Using
spacer.
a alternating pattern to remove dowels from

(1)
(2)
(3)
(4)

S
B.

Aft bulkhead and spacer assembly.

as a pair and must be
CAUTION: The spacer and propeller are balanced
or propellers from
spacers
installed together. Do not exchange
other airplanes.
surface facing up.
(1) Position spacer on a arbor press table with hub mating
tapered end into spacer.
with
dowels
(2) If dowels were removed from spacer, install
spacer.
into
press
and
dowel
(a) Lightly oil each
Extension of both dowels above
(b) Engage dowel into spacer enough to hold dowel firmly.
pressing.
face of spacer must be the same after
propeller hub.
Final dowel location will be made when spacer is installed in
mating surface facing up.
(c) Position propeller hub on arbor press table with spacer
holes.
dowel
with
aligned
(d) Place bulkhead over hub
hub.
(e) Align serial number on spacer with serial number on propeller
against the dowels for
rotate
to
bulkhead
(f) Press spacer down against hub and allow the
adjustment.
Install the Propeller and Spinner (Refer to Figure 201).
NOTE:

C.

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MAINTENANCE MANUAL
B1 786

A

SPACER

DOWEL

FORWARD BULKHEAD
ASSEMBLY
WASHER

FAD

PROPELLER

PROPELLER MOUNTING BOLT
SCREWS

DETAIL

A

051OT 1007
A0555R3001

Propeller and Spinner Installation
Figure 201 (Sheet 1)
©Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL

CAUTION: The spacer and propeller are balanced as a pair and must be
installed together.
other airplanes.

I

Do not exchange spacers or propellers from

(1) Clean the mating surfaces and install the spacer, propeller and bulkheads to crankshaft. Make
sure the serial number stamped on the side of the spacer lines up with either of the propeller
blades.
(2) Clock the propeller as follows:
(a) Find the top center (TC) mark on the aft face of the starter ring gear.

~

~~~(b)
Align one of the propeller blades with the TC mark.

(c) Rotate the propeller clockwise, looking from in front of the airplane until the bolt holes align.
(3) Install the spacer, aft bulkhead, propeller and forward bulkhead to crankshaft with mounting bolts
finger tight.
(4) Install spinner over bulkheads and install screws in forward bulkhead finger tight.

NOTE:

The aft bulkhead may need to be pushed forward slightly to engage spinner screws.
It may be necessary to rotate the spinner 180 degrees for the best spinner and screw
attach alignment.

(5) Rotate the aft bulkhead until the spinner screws can be installed with little effort.
(6) Identify on the propeller, spinner, forward and aft bulkheads index marks for screw alignment.
(7) Carefully remove spinner so the forward and aft bulkhead remains in the same aligned position.

NOTE:

The mounting bolt holes in the forward bulkhead may be undersized due to the original
torquing of the mounting bolts. This may cause the spinner to bulkhead screws
holes not to align. The required hole diameter for the forward bulkhead is 0.516
inch diameter to 0.527 inch diameter. If necessary, remove the forward bulkhead and
enlarge bolt hole using a 33/64th (0.516 inch diameter) drill.

NOTE:

If necessary, the spinner screw holes in the aft bulkhead flanges may be increased
to 0.205 inch diameter for adjustment.

(8) Secure propeller assembly using the propeller bolts and washers. Tighten the mounting bolts in
a crossing pattern to 660-780 inch-pounds dry (55-65 foot-pounds dry). Safety wire the mounting
bolts. Refer to Chapter 20, Safetying - Maintenance Practices.
D.

Install spinner in same position with index marks

E.

Check the spinner to aft bulkhead clearance.
(1) If not removed, remove upper cowling and upper nosecap. Refer to Chapter 71, Cowling Maintenance Practices.
(2) Using a 0.03 inch feeler gauge insert gauge between spinner and aft bulkhead to ensure the gap
is 0.03 inches or less. If a gauge is not available, fabricate a gauge from phenolic, aluminum or
steel that is 0.5 inches wide by 0.03 inches thick and 2.0 inches long.
(3) Replacement of the Aft Bulkhead will be required if gap is more than 0.03 inches.
(4) Adjust alternator belt tension. Refer to Chapter 24, Alternator - Maintenance Practices.
(5) Install nosecap and cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
Check the spinner to propeller clearance.
(1) Clearance between the spinner and propeller must be a minimum of 0.10 inch.
(2) If clearance is not a minimum of 0. 10 inch, remove and adjust the spinner.

F.

NOTE:

It is acceptable to trim the spinner a maximum of 0.08 inch. Trim spinner only if
maximum adjustment does not allow adequate clearance. Trim as little as possible
to obtain clearance. Apply corrosion protection. Refer to Chapter 20, Interior and
Exterior Finish - Cleaning/Painting.

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POWER PLANT

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MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

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DATE

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71 -Record of Temporary Revisions
71 -Table of Contents
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Page 1 of 1
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Number

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By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
POWERPLANT - GENERAL............................
Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Definition ..................................
ENGINE - DESCRIPTION AND OPERATION ....................
Description and Operation ..........................
10-360-1-2A - TROUBLESHOOTING ........................
Troubieshooting Chart ............................
10-360-1-2A - MAINTENANCE PRACTICES.....................
General...................................
Engine Removal/Installation..........................
Engine Cleaning...............................
Engine Storage ...............................
COWL - MAINTENANCE PRACTICES .......................
Description and Operation ..........................
Cowl Removal/installation ..........................
Cowl Shock Mounts .............................
Cowl Repair.................................
ENGINE MOUNT - MAINTENANCE PRACTICES ..................
Description and Operation ..........................
Engine Mount Procedures ..........................
Engine Mount Repairs ............................
AIR INDUCTION SYSTEM - MAINTENANCE PRACTICES..............
Description and Operation ..........................
Air Induction System Removal/Installation ...................
172S Engine Induction Air Filter Maintenance Practices.............
DRAIN LINES - MAINTENANCE PRACTICES....................
Description and Operation ..........................
Maintenance Practices............................

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201
201
201
201
201

201
201
201

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
POWERPLANT - GENERAL

1.

Scope
A.

2.

This chapter contains maintenance information on the powerplant and associated components. For
engine related information not found in this chapter, refer to applicable Textron Lycoming maintenance
manuals, listed in Introduction - List of Supplier Publications.

Definition
A.

This chapter is divided into sections to aid maintenance personnel in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief definition of the sections
incorporated in this chapter is as follows:
(1) The section on powerplant provides description, operation, troubleshooting and removal/
installation information for the engine.
(2) The section on engine cowlings provides removal and installation instructions for the engine
cowlings.
(3) The section on mounts provides removal and installation procedures for the engine mount.
(4) The section on air induction provides removal and installation procedures for the air induction
part of the fuel system.
(5) The section on drain lines provides removal and installation instructions on the various drain
lines used in the engine compartment.

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MODEL 172

MAINTENANCE MANUAL
ENGINE - DESCRIPTION AND OPERATION
1.

Description and Operation
A.

The Textron Lycoming IO-360-L2A engine is direct drive, four cylinder, fuel injected, horizontally
opposed, and air cooled. The cylinders, numbered from front to rear, are staggered to have individual
throws on the crankshaft for each connecting rod. The right front cylinder is number 1 and cylinders
on the right side of the engine are identified by odd numbers 1 and 3. The left front cylinder is number
2 and the cylinders on the left side are identified as 2 and 4.

B.

For a technical description of the engine, refer to Table 1. For an illustration of the engine, refer to
Figure 1.

C.

If more information is necessary than is given in this chapter, refer to the applicable engine manuals
given in the Introduction - List of Supplier Publications.

Table 1. IO-360-L2A Technical Description
172R Rated Horsepower at 2400
RPM

160

172S* Rated Horsepower at 2700
RPM

180

Number of Cylinders

4 Horizontally Opposed

Displacement

361.0 Cubic Inches

Bore

5.125

Stroke

4.375

Compression Ratio

8.5:1

Firing Order

1-3-2-4

Magnetos:
Right Magneto

Slick Model No. 4371 (fires at 25°
BTDC)

Left Magneto

Slick Model No. 4371 (fires at 25°
BTDC)

Spark Plugs

18MM

Torque:

420 In lbs

Valve Rocker Clearance (hydraulic
tappets collapsed)

0.028 to 0.080 inch

Fuel Injector

RSA-5AD1

Tachometer

Mechanical Drive

Oil Capacity

8.0 Quarts

Oil Pressure
Minimum Idling

20 PSI

Normal

50 to 90 PSI

Maximum

115 PSI

Oil Temperature
Normal

100°Fto 245°F

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MODEL 172
MAINTENANCE MANUAL
Table 1. IO-360-L2A Technical Description (continued)
Maximum
245°F
Dry Weight - without alternator or
vacuum pumps

278 Lbs

*And 172R Airplanes that incorporate MK172-72-01

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MODEL 172
MAINTENANCE MANUAL

B1419

ER/

;K
ESSURE
;DUCER

OIL
FILTER

:CASE
HER

FUEL PRESSURE/
FLOW TRANSDUCER

0550T1005

Engine Installation
Figure 1 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL

81420

STARTFR

FUEL FLOW
TRANSDUCER

ENGINE
MOUNT

CABIN
HEAT
DUCT

DRAIN
LINES

AIRPLANES 17280001 THRU 17281187 AND
AIRPLANES 172S8001 THRU 172S9490
0550T1006

Engine Installation
Figure 1 (Sheet 2)

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MODEL 172
MAINTENANCE MANUAL

B1421

VACUUM
PUMP

REAR
REAR

ETOS
ENGINE
DRIVEN
FUEL PUMP

M
(NOT
RATED)

FUEL
STRAINER
DRAIN

0550T1007

Engine Installation
Figure 1 (Sheet 3)

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MODEL 172

MAINTENANCE MANUAL
IO-360-L2A - TROUBLESHOOTING
1.

Troubleshooting Chart
A.

The following chart has been provided to help maintenance technicians in system troubleshooting.
This chart should be used in conjunction with Chapter 73, Fuel Injection System - Troubleshooting
and Chapter 74, Ignition System - Troubleshooting to get a comprehensive look at solutions to engine
problems. For information beyond the scope of this chapter, refer to applicable engine manuals and
publications listed in Introduction - List of Supplier Catalogs.
NOTE:

B.

If low power is suspected, the following static run-up procedures may by used inconjunction
with the troubleshooting chart to develop a diagnosis:

Static Run-Up Procedures.
(1) Align airplane 90 degrees to the right of wind direction.
(2) Run up engine at full throttle in accordance with procedures outlined in the Pilot's Operating
Handbook and FAA Approved Airplane Flight Manual.
(3) Record RPM.
(4) Realign airplane 90 degrees to the left of wind direction and perform second run-up.
(5) Record RPM from second run-up.
(6) Average the results of the RPM from the two run-ups.
(a) For the 172R, RPM must be from 2065 to 2165 RPM.
(b) For the 172S, RPM must be from 2300 to 2400 RPM.
NOTE:

Variances in atmospheric pressure, temperature and humidity can have a significant
impact on run-up RPM. Low static run-up RPM information should be used only in
conjunction with other troubleshooting procedures to determine if a problem actually
exists.

(7) If run-up indicates low power, check the following items:
(a) Do a check of the operation of the alternate air door and make sure the door remains closed
in normal operation.
(b) Do a check of the magneto timing, spark plugs and ignition harness for settings and
condition.
(c) Do a check of the fuel injection nozzles for restriction and check for correct unmetered fuel
flow.
(d) Do a check of the condition of the induction air filter. Clean or replace as required.
(e) Do an engine compression check.
TROUBLE

PROBABLE CAUSE

REMEDY

ENGINE WILL NOT START
(NO FLOW INDICATED ON
FUEL GAUGE).

No fuel to engine.

Check fuel level in tanks,
check mixture control for proper
position, fuel boost pump on and
operating, fuel valves open, fuel
filters clean and unblocked.

ENGINE WILL NOT START
(SUFFICIENT FUEL FLOW
INDICATED ON FUEL
GAUGE).

Engine flooded.

Reset throttle, clear engine of
excess fuel and attempt re-start.

ENGINE WILL NOT START
(SUFFICIENT FUEL FLOW
INDICATED ON FUEL
GAUGE) (Cont.).

No fuel to engine.

Loosen line at fuel injector
nozzle. If there is no fuel flow
with fuel flow showing on gauge,
replace the flow divider valve.

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TROUBLE

ENGINE WILL NOT RUN AT
IDLING SPEED.

ROUGH IDLING.

PROBABLE CAUSE

REMEDY

Grounded ignition switch
wires.

Check for grounded switch
wires.

Magneto improperly timed to
engine.

Retime magnetos. Refer to
Chapter 74, Ignition System Maintenance Practices.

Magneto internal timing
incorrect, weak capacitor, or
improperly adjusted breaker
points.

Refer to applicable Bendix
supplier Publications.

Fouled spark plugs.

Remove and clean, check gaps
and insulators. Reinstall with
new gaskets. Check ignition
harness.

Weak spark, magneto coils
burned out, moisture in
distributor.

Remove and bench test
magnetos, ignition harness and
spark plugs.

Leak in intake manifold.

Check hose connections,
gaskets and tighten hose
clamps and flange attaching
bolts.

Idle stop screw or idle
mixture lever incorrectly
adjusted.

Refer to Chapter 73, Fuel
Injection System - Maintenance
Practices.

Air leak in intake manifold.

Tighten loose connections or
replace damaged parts.

Weak magneto capacitor.

Install new capacitor.

Spark plugs fould by oil
escaping past piston rings.

Top overhaul engine.

Improper idle mixture
adjustment.

Refer to Chapter 73, Fuel
Injection System - Maintenance
Practices.

Manual mixture control set
for lean mixture.

Use full rich mixture for all
ground operation.

Fouled spark plugs.

Remove and clean, adjust gaps,
test ignition harness, inspect
magneto breaker points. If
persistent, top overhaul engine.

Loose or deteriorated engine
mounts.

Check mounts, tighten or install
new parts.

Burned or warped exhaust
valves and/or seats. Scored
valve stems.

Top overhaul engine.

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MAINTENANCE MANUAL

TROUBLE

ENGINE DOES NOT
ACCELERATE PROPERLY.

ENGINE RUNS ROUGH AT
HIGH SPEED.

CONSTANT MISFIRING AT
HIGH RPM.

SLUGGISH OPERATION
AND LOW POWER.

LOW FLOW ON FUEL
FLOW GAUGE.

LOW FLOW ON FUEL
FLOW GAUGE (Cont.).

PROBABLE CAUSE

REMEDY

Hydraulic tappet sticking or
worn.

Listen for tappet noise. Refer
to applicable engine overhaul
manual in Introduction - List of
Supplier's Publications.

Idle mixture too lean.

Refer to Chapter 73, Fuel
Injection System - Maintenance
Practices.

Worn throttle or mixture
linkage.

Install new parts as required.

Loose or deteriorated engine
mount pads.

Check, tighten or install new
parts.

Propeller out of balance or
track.

Remove and repair.

Spark plug gasket leaking,
improper gap, or damaged
insulator.

Install new parts.

Ignition cable insulator
deteriorated.

Test cables for leakage and
install new parts as necessary.

Improper mixture.

Check mixture control setting.

Valve spring broken.

Install new spring.

Valve warped or burned.

Top overhaul engine.

Hydraulic tappet worn or
dirty.

Remove, clean or install new
parts.

Injectors clogged.

Test and clean injectors.

Worn valve seats.

Top overhaul engine.

Worn or stuck piston rings.

Top overhaul engine.

Line to flow transducer
clogged or restricted.

Check line for bends, kinks or
obstructions.

Restricted flow to flow divider
valve.

Check mixture control for full
travel. Check for clogged fuel
filters.

Inadequate flow from pump.

Worn pump or pump plunger
shaft. Install new parts.

Interference with mixture
control.

Check mixture control for
freedom of movement.

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MAINTENANCE MANUAL

I

TROUBLE

PROBABLE CAUSE

REMEDY

HIGH FLOW ON FUEL
FLOW GAUGE.

Restricted flow beyond flow
divider valve.

Check for restricted nozzles
or flow divider valve. Clean
nozzles or install new valve.

FLUCTUATING PRESSURE
ON FUEL FLOW
INDICATOR.

Vapor in system. Excessive
fuel temperature.

If not cleared with boost pump,
drain fuel pressure line.

Fuel leak in line from flow
divider to flow transducer.

Check line, replace as required.

ENGINE DOES NOT STOP
WITH MIXTURE CONTROL
IN IDLE CUTOFF.

Mixture control valve leaking
in idle cutoff position.

Check mixture control, should
be in full idle cutoff. Check fuel
boost pump off.

HIGH OIL TEMPERATURE.

Oil cooler fins clogged.

Clean thoroughly.

Oil cooler oil passages
restricted.

Remove and flush cooler.

Oil cooler bypass valve
damaged or held open.

Remove cooler, and clean valve
and seat.

Low oil supply.

Replenish.

Oil viscosity too high.

Use correct grade of oil.

Prolonged high speed
operation on ground.

Avoid prolonged ground
operation above 1500 RPM.

Dirty/clogged oil filter.

Replace filter.

Low fuel grade.

Use correct grade of fuel.

Excessive carbon deposits
in cylinder head and on
piston.

Top overhaul engine.

Clogged cylinder fins.

Clean thoroughly.

Leaking exhaust valves.

Top overhaul engine.

Low oil supply.

Add oil.

Viscosity too low.

Use correct grade oil.

Sludge or foreign material in
relief valve.

Remove and clean valve.

Defective oil pressure gauge.

Install new gauge.

HIGH CYLINDER HEAD
TEMPERATURE.

LOW OIL PRESSURE.

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MAINTENANCE MANUAL
TROUBLE

PROBABLE CAUSE

REMEDY

Restricted oil transducer
line.

Check line from front of
crankcase to pressure
transducer for kinks or
restrictions.

Internal leak, damaged
gasket or bearing.

Major overhaul engine.

OIL LEAK AT FRONT OF
ENGINE.

Crankshaft oil seal leaking.

Install new seal.

OIL LEAK AT PUSHROD
HOUSING.

Damaged housing seal.

Install new seals.

LOW COMPRESSION.

Worn cylinder and/or rings.

Top overhaul engine or replace
defective cylinder.

Valve not properly seating.

Top overhaul engine or replace
defective cylinder.

Low grade of oil.

Use specified grade of oil.

Failed or failing bearings.

Check oil filter for metal particles,
and if found, overhaul engine.

Worn piston rings.

Install new rings.

Incorrect ring installation.

Install new rings.

EXCESSIVE OIL
CONSUMPTION.

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MODEL 172

MAINTENANCE MANUAL
IO-360-L2A - MAINTENANCE PRACTICES
1.

General
A.

2.

This section gives instructions to remove and install the engine and mount from the firewall. If more
information is necessary than is given in this chapter, refer to the applicable engine publications which
are given in the Introduction - List of Supplier Publications.

Engine Removal/Installation
A.

Remove the Engine and Mount.
NOTE:

The procedures that follow remove the engine and mount from the firewall. If the engine is
removed from the mount and the mount will stay attached to the firewall, some of the steps
will not be necessary. To remove the engine from the mount, the four bolts that connect
the four shock mounts to the engine mounting flange and the engine mount tube must be
removed.

(1) Put all cabin switches and the fuel shutoff valve in the OFF position.
(2) Remove the engine cowl.
NOTE:

The steps that follow can be done from the right side of the airplane.

(3) Disconnect the positive and negative battery leads from the battery.
(4) Loosen the clamp that attaches the flexible duct to the firewall-mounted heater valve.
(5) Remove the flexible duct from the heater valve.

WARNING: When the P lead wire Is disconnected from the magnetos to
remove the electrical ground from the magneto circuit, the
magnetos become electrically active. A ground wire must be
connected to the magnetos or the high tension wires removed
from the spark plugs to prevent accidental engine start when
the propeller Is turned. An accidental engine start can cause
Injury to persons In the area of the propeller.
(6)

Disconnect the P lead wires on the magnetos.
NOTE:

Airplanes with Garmin G1000 have EGT probes at each cylinder.

NOTE:

Airplanes without Garmin G1000 have one EGT probe in the exhaust pipe.

(7)
(8)
(9)
(10)
(11)
(12)
(13)

Remove the propeller. Refer to Chapter 61, Propeller - Maintenance Practices.
Disconnect the electrical connector from the EGT probe.
Disconnect the fuel outlet line at the fuel strainer.
Disconnect the throttle and mixture cables at the fuel/air control unit.
Record the position of the washers and spacers for assembly.
Disconnect the vacuum hoses at the firewall-mounted manifold/check valve.
Put a label on the electrical wires on the low vacuum annunciator switches, low oil pressure
transducer, and alternator.
(14) Disconnect the low vacuum annunciator switches, low oil pressure transducer, and alternator.
NOTE:

The steps that follow can be done from the left side of the airplane.

(15) Remove the tachometer drive cable or electrical connector.
(a) On airplanes without Garmin G1000, loosen and remove the tachometer drive cable.
(b) On airplanes with Garmin G1000, disconnect the electrical connector from the tachometer
sending unit.
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MAINTENANCE MANUAL
(16) Cut the tie wraps (sta straps) that attach the wire bundles to the engine mount.
(17) On the bottom side of the engine, loosen and remove the clamps that attach the starter wires to
the sump area.
(18) Remove the starter wires from the starter.
(19) Disconnect the ground strap from the engine mount.
(20) Disconnect the electrical connector (JN001) from the fuel flow transducer (UN003).
(21) Disconnect the electrical connector (JN005) from the low oil pressure switch (SN001).
(22) Disconnect the electrical connector (JN004) from the oil pressure transducer (UI006).
NOTE:

(23)
(24)
(25)
(26)
(27)
(28)
(29)

To remove the electrical connector JN004 from the baffle area, it will be necessary to
remove the two screws on the rear of the upper right baffles and remove the baffles
from each other.

Loosen the clamps that attach the battery vent tube to the drain line cluster.
Remove the vent tube through the clamps.
Remove the bolt and spacer that attach the drain lines to the firewall.
Loosen and remove the ram air tubes on the rear of the upper left baffle.
Put a stand under the tail tie-down.
Attach a hoist to the lifting strap on the top of the engine.
Lift the engine only as high as necessary with the hoist.
NOTE:

It can be necessary to get access to the bolt heads from the inside of the cockpit.

(30) Remove the bolts that attach the engine and the engine mount to the firewall.
(31) Record the sequence of the nuts, washers and flat washers.
(32) Slowly lift the engine with the hoist until the engine and the mount move from the bolts.
B.

Install the Engine and Mount.
(1) Lift the engine into position and attach the mount to the firewall with the hardware removed.
Refer to Engine Mount - Maintenance Practices for the sequence of the washer, nut and flat
washer.
(2) Torque the firewall bolts from 160 in-lbs to 190 in-lbs (18.1 N-m to 21.5 N-m).
(3) Remove the stand from the tail tie-down.
(4) Attach the ram air tubes to the rear of the upper left baffle.
(5) Attach the drain lines to the firewall with the bolt and spacer.
(6) Put the battery vent tube through the drain line clamps and tighten the clamps.
(7) Put the wires from electrical connector JN004 through the baffle cutout area.
(8) Attach the baffle pieces to each other with the screws.
(9) Connect the electrical connector (JN004) to the oil pressure transducer (UI006).
(10) Connect the electrical connector (JN005) to the low oil pressure switch (SN001).
(11) Connect the electrical connector (JN001) to the fuel flow transducer (UN003).
(12) Connect the ground strap to the engine mount.
(13) Install the starter wires to the starter.
(14) Attach the starter wires to the sump area with the clamps.
(15) Attach the wire bundles to the engine mount with tie wraps.
(16) Attach the tachometer drive cable or electrical connector.
(a) On airplanes without Garmin G1000, attach the tachometer drive cable.
(b) On airplanes with Garmin G1000, connect the electrical connector to the tachometer
sending unit.
(17) Connect the wires to the low vacuum annunciator switches, low oil pressure transducer, and
alternator.
(18) Remove the labels from the low vacuum annunciator switches, low oil pressure transducer, and
alternator.
(19) Connect the vacuum lines to the firewall-mounted manifold/check valve.
(20) Connect the throttle and mixture control cables to the fuel air control unit.

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MAINTENANCE MANUAL
(21) Connect the fuel outlet line at the fuel strainer.

(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)
(31)
3.

Airplanes with Garmin G1000 have EGT probes at each cylinder.

NOTE:

Airplanes without Garmin G1000 have one EGT probe in the exhaust pipe.

Connect the electrical connector to the EGT probe.
Install the propeller. Refer to Chapter 61, Propeller - Maintenance Practices.
Connect the P leads to the magnetos.
Connect the high tension wires to the spark plugs, if applicable.
Connect the flexible duct to the firewall-mounted heater valve.
Make sure all controls and lines are correctly installed and move freely.
Make sure all fuel fittings are tight and do not have leaks.
Connect the positive and negative leads to the battery.
Install the engine cowl.
Make sure the engine operates correctly.

Engine Cleaning
A.

4.

NOTE:

The engine can be cleaned with a stoddard solvent or equivalent chemicals. Be careful that all
openings have caps or plugs to prevent solvent entry into the engine. All electrical accessories (starter,
alternator, etc.) must have covers before the solvent is applied.

Engine Storage
A.

If the engine is removed and is to be stored, it must be preserved. Refer to Chapter 10, Storage Description and Operation for preservation procedures.

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MODEL 172
MAINTENANCE MANUAL
COWL - MAINTENANCE PRACTICES

1.

Description and Operation
A.

2.

3.

Cowl Removal/Installation
A.

Remove Cowl (Refer to Figure 201).
(1) Release quick release fasteners around perimeter of upper cowl.
(2) Remove upper cowl.
(3) Remove induction air filter bracket from lower cowl.
(4) Unscrew upper nose piece from lower nose piece.
(5) Release quick release fasteners around perimeter of lower cowl.
(6) Remove lower cowl.

B.

Install Cowl (Refer to Figure 201).
(1) Install lower cowl to engine area and secure using quick release fasteners.
(2) Install induction air filter bracket to lower cowl using quick release fasteners.
(3) Attach upper nose piece to lower nose piece using screws.
(4) Install upper cowl to engine area and secure using quick release fasteners.

Cowl Shock Mounts
A.

4.

The engine cowl consists of upper and lower sheet metal halves and upper and lower composite
nose pieces. The cowl is attached to the shock mounts using quick release, quarter turn fasteners
to allow for easy removal and installation. The nose pieces are attached to each other using screws
and nutplates.

Shock Mount Adjustment/Replacement (Refer to Figure 202).
(1) The shock mounts are riveted to brackets, which in turn are secured to the fuselage. Mounts
may be replaced as needed or adjusted with shims as shown in Figure 202.
(2) If new shock mounts or brackets are installed, careful measurements should be taken to ensure
new parts are positioned correctly on the firewall. New parts are not pre- drilled and care should
be taken to align new shock mounts with existing cowl openings. If required, sheet aluminum
may be used as shim stock to provide proper cowl contour.

Cowl Repair
A.

For repair procedures to the cowl, refer to the Structural Repair Manual.

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MAINTENANCE MANUAL

A0552T3001
B0550T1002
C0552T1003

DETAIL B
Engine Cowl Installation
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
B1788

DETAIL A
ENGINE

COWL
SNUBBER
BRACKET
ASBESTOS
SEAL
SHOCK
MOUNT
ACKET
-SNUBBER
SHIM

FIREWALL

SNUBBER
SUPPORT

NOSE(

DETAIL B

DETAIL C
NOTE:

SHIM CAN BE INSTALLED AS REQUIRED (MAXIMUM 4) BETWEEN SNUBBER
SUPPORT AND SNUBBER TO OBTAIN A MAXIMUM GAP OF 0.125 INCH BETWEEN
SNUBBER AND COWL SNUBBER BRACKET.
0510T1007
A0511T1006
B0552T1002
C0552T1002

Engine Cowl Shock Mount Installation
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL
ENGINE MOUNT

-

MAINTENANCE PRACTICES

1.Description and Operation
A. The dynafocal engine mount is made of 4130 steel and uses four rubber mounts to isolate engine
noise and vibration from the engine mount. The mount is attached to the fuselage at four points on
the firewall using bolts, washers and nuts.
2.

Engine Mount Procedures
A. Shock Mount Procedures (Refer to Figure 201).
(1) The shock mounts which connect the engine to the engine mount are of rubber and metal
construction and are assembled in a sandwich to isolate noise and vibration from the cabin
area. Shock mounts should be assembled as illustrated in Figure 201. Nuts should be torqued
from 450 to 500 In-lbs upon installation.
(a) If necessary, adjust the oil filler tube clearance. Make sure the oil filler tube does not touch
the engine mount or hoses.
NOTE:

B.

C.

3.

One or two washers are permitted between the mounting and engine flange to
adjust the oil filler-tube clearance. Both of the bottom mounts must have the
same number of washers between the mounting and engine flange. Both top
mounts must have the same number of washers between the mounting and
engine flange.

(2) The shock mounts should never be cleaned with any type of solvent. If shock mounts need
cleaning, use a clean, dry cloth.
(3) Shock mounts should be inspected when removed. Metal components should be inspected
for cracks and excessive wear due to aging and deterioration. Rubber components should be
inspected for separation, swelling, cracking or a pronounced set of the pad. Shock mounts
showing any of these signs should be replaced.
Firewall Mounting Procedures (Refer to Figure 202).
(1) The engine mount should be secured to the firewall using bolts, washers, flatwashers and nuts
as illustrated in Figure 202. Nuts should be torqued from 160 to 190 In-lbs.
Removal Notes.
(1) Specific instructions for removing the engine mount have been included earlier in this chapter
under 10-360-L2A - Maintenance Practices.

Engine Mount Repairs
A. The engine mount may be repaired using procedures described in the Single Engine 1996 and On
Structural Repair Manual.

© Cessna Aircraft Company

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MAINTENANCE MANUAL

B1789

NOTE:

BOL

ONE OR TWO WASHERS PERMITTED.
BOTH TOP MOUNTS MUST HAVE THE
SAME NUMBER OF WASHERS.
O1UUN1 I 0 MUZ- I I1MVLz
3ER OF WASHERS.

ENGINE
FLANGE

SPACER
WASH ER

ENGINE
MOUNT

(NOTE)
UPPER RIGHT HAND SHOCK MOUNT

BC
ENGINE
MOUNT
WASHER
(NOTE)

MOUNTING
DAMPER

4UT
MOUNTING

FLANGE

WASHER

LOWER RIGHT HAND SHOCK MOUNT

05511002
05511002

Engine Shock Mount Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL
Bi1790

NOTE:

ONE OR TWO WASHERS PERMITTED.
BOTH TOP MOUNTS MUST HAVEF THE

WASH ER

Li MOUNT
v

MOUNTING

UPPER LEFT HAND SHOCK MOUNT
WASHER

ENGINE
MOUNT

FL
MOUNTING

MOUNTING

LOWER LEFT HAND SHOCK MOUNT

BOLT
05511002
05511002

Engine Shock Mount Installation
Figure 201 (Sheet 2)

©Cessna Aircraft Company

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MAINTENANCE MANUAL

B

A

0
NUT

DETAIL

A

051 OT1007
A0551TIO01

Firewall Engine Mount Installation
Figure 202 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
AIR INDUCTION SYSTEM - MAINTENANCE PRACTICES
1.

Description and Operation
A.

B.
2.

3.

Ram air to the engine goes into the induction air box through the induction filter in the forward part of
the lower engine cowl. From the induction air box, the air is pointed to the inlet of the fuel/air control
unit and through the intake runners of the related cylinders.
For more information of how the air induction system relates to fuel injection, refer to Chapter 73, Fuel
Injection System - Description and Operation.

Air Induction System Removal/Installation
A.

Remove the System Components (Refer to Figure 201).
(1) Loosen the fasteners that attach the air filter bracket to the lower cowl.
(2) Remove the air filter bracket and the air filter.
(3) Remove the lower cowl. Refer to Cowling - Maintenance Practices.
(4) Loosen the clamps on the duct to disconnect the filter box from the induction air elbow.
(5) To remove the induction air elbow, loosen the clamps at the inlet adapter and at the drain line.
(6) Move the induction air elbow down and away from the inlet adaptor.

B.

Install the System Components (Refer to Figure 201).
(1) Put the induction air elbow in position to the inlet adaptor and attach with the clamp.
(2) Attach the drain line to the induction air elbow with the clamp.
(3) Install the lower cowl. Refer to Cowling - Maintenance Practices.
(4) Attach the air filter and the air filter bracket to the lower cowl with the quick release fasteners.

172S Engine Induction Air Filter Maintenance Practices
A.

The induction air filter keeps dust and dirt from the induction system. The air filter must be kept in
a good clean condition. More engine wear is caused through the use of a dirty or damaged air filter
than is usually thought. The frequency with which the filter must be removed, examined and cleaned
will be given by aircraft conditions of operation. A good general rule, however, is to remove, examine
and clean the filter at least every 100 hours of engine operation time, and more frequently if given by
the conditions of operation. Under very dusty conditions, daily servicing of the filter is recommended.
To service the induction filter, do the steps that follows.
(1) Remove the filter from the airplane.
NOTE:

Be careful when the filter element is cleaned with compressed air.

NOTE:

Arrows on the filter case show the direction of normal airflow.

(2) Clean the filter with compressed air (not over 100 psi) from the direction opposite of normal
airflow.
NOTE:

(3)

The bond holds the paper pleats to the face screen and, if the bond is broken, the
pleats are free to move and decrease filter operation. A face screen that is loose or
has gaps shows that the bond is broken and the filter element must be replaced.

Do a check to make sure the paper pleats are correctly bonded to the face screen.

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MODEL 172
MAINTENANCE MANUAL

B1

A
SPRING

DETAIL

B

ALTERNATE AIR DOOR

INLET
ADAPTOR

DRAIN
LINE
CLAMPS

DETAIL A

0510T1007
A0550T1002
B0550T1003

Induction Air Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

CAUTION: Do not use solvent or cleaning fluids to wash the filter. Use only a
water and household detergent solution when washing the filter.
(4) After compressed air has been blown through the filter, the filter can be washed, if necessary, in
a solution of warm water and a mild household detergent. A cold water solution can be used.
NOTE:

The filter assembly can be cleaned with compressed air a maximum of 30 times or it
can be washed a maximum of 20 times.

NOTE:

A new filter must be installed at 500 hours of engine operation or one year, whichever
occurs first. A new filter must be installed if the filter is damaged.

(5) Flush the filter with clear water until the water from the filter is clear. Let the water drain from the
filter and dry with compressed air (not over 100 psi).
NOTE:

The panels of the filter can have distortion when wet, but they will go back to their
normal shape when dry.

(6) Make sure the airbox is clean.
(7) Examine the filter and replace if applicable.
(8) Install the filter in the airbox with the gasket on the aft face of the filter frame and with the flow
arrows on the filter frame pointed in the correct direction.

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MODEL 172
MAINTENANCE MANUAL
DRAIN LINES - MAINTENANCE PRACTICES
1.

Description and Operation
A.

2.

Various components within the engine compartment are equipped with drain lines to allow fluid and/or
vapor to escape and vent to the atmosphere. These lines are typically secured using hose clamps,
and are routed together in a cluster on the left side of the forward firewall.

Maintenance Practices
A.

Maintenance practices for all drain lines are typical. Line removal and installation consists of removing
clamps and other devices used to secure the lines to various structure. Lines should be checked for
condition and security when removed, and installed in reverse order.

B.

For an illustration of various drain lines, refer to Figure 201.

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MODEL 172
MAINTENANCE MANUAL

FUEL DISTRIBUTION VALVE DRAIN HOSE

CLAMP
INLET DRAIN HOSE
INLET DRAIN LINE
DETAIL FUEL DISTRIBUTION VALVE
DETAIL A
DRAIN LINE
Engine Drain Lines Installation
Figure 201 (Sheet 1)

71-70-00
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CHAPTER

ENGI INE
FUEL AN D
CONT RO L

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

73-00-00

Page 1

Apr 7/2003

73-00-0 1

Pages 1-3
Pages 101 -102

Apr 7/2003

73-Title
73-List of Effective Pages
73-Record of Temporary Revisions
73-Table of Contents

73-00-01
73-00-01

Pages 201-205
Pages 201 -202

73-30-00

©Cessna Aircraft Company

73

-

Janl1/2007
Janl1/2007
Jan 3/2005

LIST OF EFFECTIVE PAGES

Page 1 of 1
Janl1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
ENGINE FUEL AND CONTROL - GENERAL ....................
Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Definition ..................................
FUEL INJECTION SYSTEM - DESCRIPTION AND OPERATION...........
General...................................
Description .................................
Operation..................................
Fuel Injection System - TROUBLESHOOTING....................
General...................................
Fuel Injection System Troubleshooting.....................
FUEL INJECTION SYSTEM - MAINTENANCE PRACTICES .............
General...................................
Precautions.................................
Fuel/Air Control Unit Removal/installation ...................
Fuel Distribution Valve Removal/installation ..................
Injection Nozzles Removal/Installation.....................
Injection Nozzle Flow Test ..........................
Idle and Mixture Adjustment..........................
Injector Nozzle Cleaning ...........................
Fuel Strainer Cleaning ............................
Air Throttle Shaft Lubrication .........................
FUEL FLOW INDICATOR - MAINTENANCE PRACTICES ..............
General...................................
EGT/Fuel Flow Gage Removal/Installation...................
Transducer and Line Removal/installation ...................

©Cessna Aircraft Company

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73- CONTENTS

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ENGINE FUEL AND CONTROL - GENERAL
1.

Scope
A.

2.

This chapter provides information on the fuel injection system used for the 10-360- L2A engine.
Information beyond the scope of this chapter can be found in Chapter 28, Fuel - General and in
various publications which are listed in Introduction - General.

Definition
A.

This chapter is divided into sections and subsections to assist maintenance personnel in locating
specific systems and information. The following is a brief description of each section. For locating
information within the chapter, refer to the Table of Contents at the beginning of the chapter.
(1) The section on fuel injection covers procedures used to troubleshoot and maintain the fuel
injection system.
(2) The section on fuel flow indicator covers procedures used to maintain the indicating portion of
the system.

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MODEL 172
MAINTENANCE MANUAL
FUEL INJECTION SYSTEM - DESCRIPTION AND OPERATION
1.

General
A.

2.

3.

This section covers the RSA Fuel Injection system used on the IO-360-L2A engine. For a schematic
of the fuel injection system, refer to Figure 1.

Description
A.

The fuel injection system is a low pressure, multi nozzle, continuous flow system which injects raw fuel
into the engine cylinder heads. The injection system is based on the principle of measuring engine
air consumption to control fuel flow. More air flow through the venturi will result in more fuel being
delivered to the engine, and less air flow through the venturi results in a decreased flow of fuel to
engine.

B.

System components consist of the fuel/air control unit, the fuel distribution valve (flow divider), injection
nozzles (4 total) and lines used to connect the components. A description of the components is as
follows:
(1) Fuel/Air Control Unit - The fuel/air control unit, also known as the 'servo regulator,' is located
on the underside of the engine and integrates the functions of measuring airflow and controlling
fuel flow. The control unit consists of an airflow sensing system, a regulator section and a fuel
metering section.
(2) Fuel Distribution Valve - The fuel distribution valve, also known as a 'spider' or a flow divider,
is located on top of the engine and serves to distribute fuel evenly to the four cylinders once it
has been regulated by the fuel/air control unit. Also attached to the fuel distribution valve is a
rigid line which feeds into a pressure transducer. This transducer measures fuel pressure and
translates that reading into fuel flow at the cockpit indicator.
(3) Injection Nozzles - Each cylinder contains an injection nozzle, also known as an air bleed nozzle
or a fuel injector. This nozzle incorporates a calibrated jet that determines, in conjunction with
fuel pressure, the fuel flow entering each cylinder. Fuel entering the nozzle is discharged through
the jet into an ambient air pressure chamber within the nozzle assembly. This nozzle assembly
also contains a calibrated opening which is vented to the atmosphere, and allows fuel to be
dispersed into the intake portion of the cylinder in an atomized, cone-shaped pattern.

Operation
A.

Fuel is stored in the wing tanks and is delivered to the fuel injection system via a series of lines, valves
and pumps. From the engine-driven fuel pump, fuel enters the fuel/air control unit, passes through
the fuel distribution valve, and is routed to individual injection nozzles at each cylinder.
NOTE:

B.

For a schematic of the entire fuel system, refer to Chapter 28, Fuel Storage and Distribution
- Description and Operation, Figure 1.

The heart of the injection system is the fuel/air control unit, which occupies the position ordinarily
used by the carburetor at the engine intake manifold inlet. The fuel/air control unit is comprised of
an integrated airflow sensing system, a regulator section and a fuel metering section. Operation of
the fuel injection system is based on the principle of measuring airflow and using the airflow signal to
operate a servo valve. The accurately regulated fuel pressure established by the servo valve, when
applied across the fuel control system, makes fuel flow proportional to airflow.
(1) THE AIRFLOW SENSING SYSTEM consists of a throttle body which houses the air throttle
valve, the venturi, servo valve and fuel control unit. The differential pressure between impact air
and the venturi throat pressure is a measurement of the velocity of the air entering the engine.
These pressures are vented through drilled channels in the throttle body to both sides of an
air diaphragm and create a force across the diaphragm. A change in air throttle position or a
change in engine speed will change the air velocity, which in turn changes the force across the
air diaphragm.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

B235

I

IDLE VA
CON
T...L.IVR
THROTTLE
LEVER
JTTLE LEVER
LINK AGE

MANUAL MIXTURE
U

CONTROL AND IDLE

VIEW A-A

CUT-OFF LEVER

!I 1
"

I

,;-- …------................

jI

I IE

THROTTLE VALVE
I

IDLE SPEED
ADJUSTMEN1
BALL VAI VF

CONSTANT HEAD
IDLE SPRING

N

CONSTANT EFFORTSPRING
AIR DIAPHRAGM
FUEL DIAPHRAGM'
ees
*
1///////\
l/////
r'/"///

/,l

INLET AIR
I (SCOOP PRESSURE)
/vclTII

V LI

IDI I 1I
IrTInTl
I II,
U_
...

.

v*

.

,1/8 INCH STAINLESS
STEEL LINE

PRESSURE BELOW

THROTTLE
iii.....i
..
B:r::

FUEL INLET
PRESSURE
TO FUEL NOZZLE
(ONE PER
CYLINDER)

METERED FUEL
PRESSURE (P1)
METERED FUEL
PRESSURE (P2)

Tfr
CIl ICI
FLOW GAUGE

__
NOZZLE DISCHARGE
__B PRESSURE

FLOW GAUGE

05e16T2001

Fuel Injection System Schematic
Figure 1 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL -172
MAINTENANCE MANUAL
(2) THE REGULATOR SECTION contains the air diaphragm mentioned in the preceding paragraph
and a fuel diaphragm. Fuel inlet pressure is applied to one side of the fuel diaphragm. The other
side of the fuel diaphragm is exposed to fuel that has passed through the metering jet (metered
fuel pressure). The differential pressure across the fuel diaphragm is referred to as the fuel
metering force.
(a) The air metering force applied to the air diaphragm is transmitted through the regulator
stem and tends to move the ball valve in the opening direction. The fuel metering force
across the fuel diaphragm acts to oppose the air metering force and tends to close the ball
valve. Because the air forces are very low in the idle range, a constant head idle spring is
provided to maintain an adequate fuel metering force at low rpm.
(b) As the air metering force increases, the spring compresses until the spring retainer touches
the air diaphragm and acts as a solid member. The constant effort spring produces a force
which provides a smooth transfer from idle to low power cruise operation. Whenever the
air metering, fuel metering and spring forces are balanced, the ball valve maintains a fixed
position.
(3) THE FUEL METERING SECTION is contained within the throttle body casting and consists of an
inlet fuel screen, a rotary idle valve and a rotary mixture valve. Both idle speed (closed throttle
position) and idle mixture (relationship between throttle position and idle valve position) may be
adjusted externally to meet individual engine requirements.
(a) The idle valve is connected to the throttle valve by means of an external adjustable link.
The idle valve controls fuel flow through the low speed range of operation and is adjustable
to obtain good idling characteristics without affecting fuel metering in the high power range.
(b) The mixture control valve gives full rich mixture on one stop and a progressively leaner
mixture as it is moved toward idle cutoff. The full rich stop defines sea level requirements
and the mixture control provides for altitude leaning.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
Fuel Injection System

-

TROUBLESHOOTING

1.

General
A.
This section gives troubleshooting information for the installation of the fuel injection system.

2.

Fuel Injection System Troubleshooting
A.
Do the troubleshooting procedures if the problem is found on the chart. Refer to Table 101.

Table 101. Fuel Injection System Troubleshooting
PROBLEM
HIGH FUEL FLOW READING.

UNSATISFACTORY
FUEL
CUTOFF.
ENGINE WILL NOT INCREASE TO
THE NECESSARY RPM.

PROBABLE CAUSE
SOLUTION
Plugged nozzle if the high fuel flow Remove and clean the nozzles.
reading is combined with a loss of Soak the nozzles in Hoppes
power and roughness.
#9 Gun cleaning solvent for 20
minutes. Rinse the nozzles in a
Stoddard solvent. Blow dry the
nozzles. Do a check of the system
for contamination.
Faulty
gage
or
pressure Replace the gage or pressure
transdiir-pr
tranndijcpr
Incorrect installation of the aircraft Adjust the linkage. Refer to servo
linkage to the mixture control.
mixture value RS-16.
Contamination in the air chamber. Refer to Precision Airmotive
Corporation service information
_____

ROUGH IDLE.

_____
_____

___________________________Contamination

____

letter RS-40.

Small air leaks in the induction
system through loose intake pipes
or a damaged 0-ring,

Do a check of the clamps and
connectors.
Repair leaks as
necessary.

Large air leaks in the induction
system.

Repair leaks as necessary.

Fuel vaporizes in the fuel lines
or distributor. Found only in high
ambient temperature conditions or
after a long operation at a low RPM
setting.

Keep temperatures low:
Avoid long ground runs.
During a hot engine restart:
Operate the engine at 1,200
- 1,500 for several minutes to
reduce residual heat in the engine

____
____ ___ ___

LOW TAKEOFF FUEL FLOW.

_____

Faulty
gage
transducer.

____

or

___

___

pressure

in the flow divider.

©Cessna Aircraft Company

compartment.

Replace the gage or pressure
transducer.
Clean the flow divider.

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MAINTENANCE MANUAL
Table 101. Fuel Injection System Troubleshooting (continued)
ENGINE IS DIFFICULT TO START. Incorrect starting procedure.

ENGINE OPERATES ROUGH.

Refer to the Pilot's Operating
Handbook.

Flooded engine.

Crank the engine to clear it with the
throttle open and the mixture in the
IDLE/CUTOFF position.

Throttle valve is opened too far.

Open the throttle to approximately
800 RPM.

A prime that is not sufficient
(usually combined with a backfire).

Increase the quantity of priming.

Adjust the mixture control. If the
mixture is too rich, the engine will
run smoothly when leaned. If the
mixture is too lean, the engine will
run smoothly when the mixture is
enriched. Adjust idle mixture to
give a 10 - 50 PRMV rise at idle.
(usually Remove and cla tIIe nozzles
nozzle(s)
Plugged
combined with high takeoff fuel Soak the nozzles in a Hoppes
#9 Gun cleaning solvent for 20
flow).
minutes. Rinse the nozzles with
a Stoddard solvent. Blow dry the
nozzles. Do a check of the system
for contamination.

Too rich or too lean mixture.

Air leak in the induction system.

Do a check for leaks.

Air leak in the fuel line from the fuel Do a check for the leak. Connect
clear tubing between the servo
tank to the servo.
and the flow divider and look for
Find and correct
air bubbles.
the source of the leak. This can
include the boost pump or the
engine-driven pump.
Flow divider sticks.

Do an inspection of the flow divider.
Clean the flow divider.

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MODEL 172

MAINTENANCE MANUAL
FUEL INJECTION SYSTEM

-

MAINTENANCE PRACTICES

1.

General
A. This section provides instructions for removal/installation, adjustment and cleaning of various
components used in the fuel injection system. For maintenance information beyond the scope of
this section, refer to applicable fuel injection component maintenance manuals which are listed in
Introduction - List of Supplier Publications.

2.

Precautions
A. Observe the following general precautions and rules during fueling, defueling, fuel bay purging,
repairing, assembly or disassembly of system components, and electrical system checks and repairs
on the airplane fuel system.
(1) Plugs or caps should be placed on all disconnected hoses, lines and fittings to prevent residual
fuel drainage, thread damage, or entry of dirt or foreign material into fuel system.
(2) Any time fuel system is opened, flush system with 1/2 gallon of fuel at the inlet of servo and flow
divider using the fuel boost pump.
(3) When working on fuel injection system, keep all parts clean and free of contaminants.

3.

Fuel/Air Control Unit RemovaVlnstallation
A. Remove Fuel/Air Control Unit.
(1) Place cockpit-mounted FUEL SHUTOFF valve in the OFF position.
(2) Remove lower cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(3) Remove clamp securing induction air elbow to inlet adaptor.
(4) Disconnect fuel inlet and outlet lines from control unit.
(5) Remove mixture and throttle control linkages from control unit. Note number and position of
washers for reinstallation.
(6) Cut safety wire at base of control unit. Remove bolts securing inlet adaptor and throttle cable
bracket to base of control unit and mixture cable bracket.
(7) Remove nuts, lock washers and flat washers securing control unit to oil sump/intake manifold.
Cover engine intake opening and place control unit in a sealed, dust-free environment to prevent
accumulation of foreign particles into unit.
B. Install Fuel/Air Control Unit.
(1) Remove engine intake cover from sump area.
(2) Install control unit, spacer and gaskets to sump using washers, new lock washers and nuts.
Finger tighten nuts to control unit.
(3) First torque nuts in a crisscross (opposite) pattern to 90 inch-pounds and then retorque nuts in
the same manner to a final torque value of 180-200 inch pounds.
(4) Install inlet adaptor and throttle cable bracket to base of control unit using hardware removed
above. Safety wire bolts.
(5) Install mixture cable bracket.
(6) Install mixture and throttle control linkages to control unit. Ensure all washers are in proper
position. Refer to Chapter 76, Throttle Control - Maintenance Practices, Figure 201 and Chapter
76, Fuel Mixture Control - Maintenance Practices, Figure 201 for an illustration of washer and
linkage sequence.

CAUTION: Do not back the nuts off to line the cotter pin hole up with the
castellations in the nut.

(7) Torque each nut to 30 inch-pounds and then proceed tightening the nut until the cotter pin hole
lines up with the castellation in each nut. Do not exceed 50 inch-pounds.
(a) If the cotter pin hole and the nut castellations will not line up, install a different thickness
NAS1 149F0363P washer or use a thin, NAS1 149F0332P washer at the location between
the throttle cable rod end and S1450-3-14-032 washer to obtain the specified torque on
the nut. It may also be necessary to use a different AN310-3 nut.
(8) Install cotter pins.

© Cessna Aircraft Company

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MODEL 172
MAINTENANCE MANUAL
(9) Move the mixture and throttle control through each controls entire range of movement and ensure
that there is no binding.
(10) Connect fuel inlet and outlet lines to control unit.
(11) Secure induction air elbow to inlet adaptor using clamp.
(12) Install lower cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(13) Place cockpit-mounted FUEL SHUTOFF valve in the ON position.
(14) Check for leaks during engine run.
4.

5.

Fuel Distribution Valve RemovaVinstallation
A.

Remove Fuel Distribution Valve.
(1) Remove upper cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Disconnect all lines leading in to and out of fuel distribution valve.
(3) Remove nuts, bolts, washers and spacers securing fuel distribution valve to engine case.

B.

Install Fuel Distribution Valve.
(1) Secure fuel distribution valve to engine case using nuts, bolts, washers and spacers. Torque to
75 In-lbs.
(2) Reinstall all lines leading in to and out of fuel distribution valve.
(3) Check for leaks during engine run.
(4) Install upper cowling. Refer to Chapter 71, Cowling - Maintenance Practices.

Injection Nozzles Removal/installation
A.

Remove Injection Nozzles.
(1) Remove upper cowling. Refer to (Thapter 71, Cowling - Maintenance Practices.
(2) Remove- rigid fuel lines leading into individual nozzles.
(3) Remove nozzles from cylinders.

B.

Install Injection Nozzles.

CAUTION: Use only fuel-soluble lubricants (such as engine oil) on the nozzle
threads during installation.
(1) Install nozzles to intake cylinders. Torque from 55 to 60 In-lbs.
(2) Install rigid fuel lines to nozzles. Torque 25 to 50 In-lbs.
(3) Install upper cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
6.

Injection Nozzle Flow Test
A.

Check Injection Nozzles For Plugging.
(1) If nozzle plugging is suspected, disconnect injector lines at the nozzles.
(2) Cap nozzles with clean valve stem caps to protect nozzles from contamination during removal.
(3) Remove nozzles. Refer to Injection Nozzles Removal/Installation.
(4) Pull up injector lines taking care that lines are not kinked.
(5) Install nozzles back into lines and torque from 25 to 50 in-lbs.
(6) Using clear containers (bottles with graduations are preferred) flow fuel into containers using
aircraft boost pump and observe nozzle discharge pattern.
(7) When the mixture control is placed in the full rich position the nozzles should display a pencil
stream pattern. The nozzles should also flow the same amount of fuel from cylinder to cylinder.
If an unusual flow pattern or an unequal amount of fuel is noted in any of the containers the
nozzles should be thoroughly cleaned. Refer to Injector Nozzle Cleaning.
(8) After cleaning install clean protective valve stem caps. It is recommended that after cleaning the
nozzles, they be reinstalled in the injector lines and a nozzle flow check is conducted to verify
that the nozzles are clean.
(9) Following a successful flow check reinstall the protective flow caps and reinstall the nozzles in
the cylinders and torque from 55 to 60 in-lbs..
(10) Remove protective caps and reinstall injector lines to the nozzles and torque from 25 to 50 in-lbs.
(11) Perform leak check.

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MODEL 172
MAINTENANCE MANUAL

7.

Idle and Mixture Adjustment
A. For airplanes with the RSA Fuel Injection System, refer to the Precision Airmotive Service Letter SIL
RS-67.
B. Adjustment Procedures (Refer to Figure 201).

WARNING: During adjustment procedure stay clear of propeller and/or
propeller blast to avoid possible injury or death.
NOTE:

-

Ensure that the alternate air door is in the closed position during this adjustment.

(1) Run engine to warm the oil to 150 degrees F.
NOTE:

*

If the cowling is off, it may not be possible to attain 150 degrees oil temperature at
cooler ambient temperatures. In that case it will be necessary to set idle speed and
mixture at a lower temperature.

~~(2)

With the mixture control in the full rich position, set the idle speed to 675 +25 or -25 RPM.
(3) Advance the throttle to approximately 1800 RPM and immediately return it to idle. Idle speed
should be approximately the same as set above.

CAUTION: Adjust the fuel mixture control by rotating the knob briskly for
approximately the first inch, then very slowly until the peak rpm
is obtained and the engine speed starts to drop off. When the
engine speed first starts to increase, a slight rise in rpm will be
obtained. Then a speed hesitation will occur as the mixture control
is continually moved toward the lean position. Do not mistake this
as the total rpm rise. Continue the slow rotation movement of the
mixture control until observing or sensing a drop in the engine rpm.
This is the total rpm rise which indicates the mixture strength at the
engine idle speed.
(4)

Rotate the mixture control to lean the mixture. Note the rise in engine RPM. This rise should be
set to 10 to 50 RPM.
NOTE:

To aid in the adjustment of the fuel mixture, a stamp on one half of the clevis on the
fuel servo indicates the direction that the thumb wheel should be moved to enrichen
the mixture and increase the RPM rise. Likewise, rotating the thumb wheel in the
opposite direction will lean the mixture and decrease the RPM rise.

(5) After each adjustment is made, the engine speed should be increased to approximately 1800
RPM and held for about 10-1 5 seconds to clean the spark plugs and clear the cylinders of excess
fuel.
(6) Return the throttle to the idle position. Repeat procedure until desired RPM rise at idle is
obtained.
NOTE:

(7)

If the mixture was excessively rich or lean when this procedure was started, the
engine speed will require readjustment as the fuel mixture is adjusted to the desired
value. Set the idle speed to the specified RPM after the mixture has been set to
obtain the 10 to 50 RPM rise on lean out.

Run engine to full throttle and back to idle to verify that the setting has not changed.

(DCessna Aircraft Company

73-00-0 1

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B235

UEL
JLET
MtE I EMIl

JET

I.

IDLE VALVE LE\
CON NFC.TFn T(
*
TH R(DTTLE LEVER
LINK AGE

*

I,

I

#5I

.I

~~~~~~~~~~IVIMI-WJL-L
IVII/\ I
LJFL
VIEW

A-A

CONTROL AND IDLEL
CUT-OFF LEVER

…~~~TRTL

I.

AV

IDLE SPEED ADJUSTMENI
WALL V/ALVr-

CONSTANT HEAD
IDLE SPRING
CONSTANT EFFORT--_
SPRING
AIR DIAPHRAGM

-

FUEL DIAPHRAGMv<
INLET AIR
(SCOOP PRESSURE)
VENTURI SUCTION
LM
...

PRESSURE BELOW
TH ROTTLE
FUEL INLET

PRESSURE
___METERED

FUEL

PRESSURE (Pl)
METERED FUEL
PRESSURE (P2)

I %.I

%J"L.

FLOW GAUGE

NOZZLE DISCHARGE
'M PRESSURE

0516T2001

Idle and Mixture Adjustment
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
(8) Re-cowl engine and run until oil temperature is 150 degrees F (minimum) to verify settings have
not changed.
NOTE:

Small changes in the idle speed and RPM are acceptable. Any large variations should
be investigated.

8.

Injector Nozzle Cleaning
A. The injector nozzles should be cleaned at time intervals set forth in Chapter 5, Inspection Time Limits.
B. Cleaning Procedures.
(1) Remove nozzles from engine. Individual two-piece nozzles should be kept as matched
assemblies.
(2) Inspect carefully for evidence of varnish build up and/or contaminated screens.
(3) Soak nozzles in Methyl Ethyl Ketone, Acetone or other suitable solvent to remove all
contamination and varnish from nozzle. Stubborn deposits may benefit from ultrasonic cleaning
methods.
(4) Dry nozzles using compressed shop air not to exceed 30 PSI. Blow through nozzle in direction
opposite of fuel flow.
(5) Install nozzles to intake cylinders. Torque from 55 to 60 In-lbs.
(6) Install rigid fuel lines to nozzles. Torque 25 to 50 In-lbs.
(7) Perform leak check.

9.

Fuel Strainer Cleaning
A. The fuel strainer should be cleaned at time intervals set forth in Chapter 5, Inspection Time Limits.
B. Cleaning Procedures (Refer to Figure 201).
(1) Remove fuel inlet hose to access fuel strainer.
(2) Remove and clean fuel strainer in Stoddard solvent.
(3) Using new 0-rings, install fuel strainer to control unit. Torque 65 to 70 In-lbs.
(4) Install the fuel inlet hose. Use a wrench to hold the fuel strainer adapter and torque to 270 to
300 in-lbs.
(5) Perform leak check.

10.

Air Throttle Shaft Lubrication
A. The air throttle shaft should be lubricated at time intervals set forth in Chapter 5, Inspection Time
Limits.
B. To lubricate air throttle shaft, apply a drop of engine oil to ends of air throttle shaft in such a manner
that the oil can work into throttle shaft bushings.

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
FUEL FLOW INDICATOR - MAINTENANCE PRACTICES
1.

2.

General
A.

Airplanes without Garmin G1000, engine fuel flow is measured by an engine-compartment attached
transducer and an indicator in the cockpit. Components of the system are the fuel flow transducer,
the EGT/Fuel Flow gage in the cockpit, wiring to connect the two electrical components and fuel line
from the fuel distribution valve to the transducer.

B.

Maintenance practices are given for the removal and installation of the components.

C.

Airplanes with Garmin G1000 use the fuel flow transducer installed on the engine and the fuel flow
indicator on the Garmin Display Units to show fuel flow. For information applicable to the Garmin
Display Units, refer to Garmin Display Unit - Maintenance Practices.

EGT/Fuel Flow Gage Removal/Installation
NOTE:

3.

The fuel flow gage is on the right half of the dual-function EGT/Fuel Flow gage on the left side
of the instrument panel.

A.

Remove the Fuel Flow Gage.
(1) Make sure all electrical power to the airplane is off.
(2) Remove the screws that attach the gage to instrument panel.
(3) Carefully remove the gage from the bottom side of the instrument panel and disconnect electrical
connector from the gage.

B.

Install the Fuel Flow Gage.
(1) Connect the electrical connector to the gage.
(2) Install the gage in the instrument panel with the screws.
(3) Make sure the gage operates correctly.

Transducer and Line Removal/Installation
NOTE:

Transducer and line removal and installation are typical for all avionics packages.

A.

Remove the Transducer (Refer to Figure 201).
(1) Make sure the electrical power to airplane is off.
(2) Remove the upper cowl. Refer to Chapter 71, Cowling - Maintenance Practices.
(3) Disconnect the electrical connector from the fuel flow transducer.
(4) Disconnect the fuel line from the fuel distribution valve to the transducer.
(5) Remove the transducer from the baffle.
(6) Remove the fitting from the transducer.

B.

Install the Transducer (Refer to Figure 201).
(1) Install the fitting and the O-ring in the transducer.
(2) Install the fuel flow transducer to the baffle.
(3) Connect the fuel line from the fuel distribution valve to the transducer.
(a) Torque the fuel line to 25 in-lbs to 50 in-lbs (2.8 N-m to 5.6 N-m).
(4) Connect the electrical connector to the fuel flow transducer.
(5) Install the upper cowl. Refer to Chapter 71, Cowling - Maintenance Practices.
(6) Make sure the gage operates correctly.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1795

A
ELECTRICAL CONNE(
FUEL DISTRIBUTION
VALVE

FUEL FLOW TRA
FITTING O-RING
(
ENGINE BAFFLE

NUT

RIGID FUEL LINE
CLAMP

DETAIL A
0510T1007
A0516T1009

Fuel Flow Indicating Installation
Figure 201 (Sheet 1)

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CHAPTER

IGNITION

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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Apr 7/2003

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Apr 7/2003

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Pages 201-205

Apr 7/2003

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Apr 7/2003

74-Title
74-List of Effective Pages
74-Record of Temporary Revisions
74-Contents

74 - LIST OF EFFECTIVE PAGES
© Cessna Aircraft Company

Page 1of 1
Jan 3/2005

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
IGNITION SYSTEM - GENERAL ............................

......................

Scope......................................................................
Tools, Equipment and Materials ..............................................
Definition ...................................................................
IGNITION SYSTEM - TROUBLESHOOTING .......................................

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74-10-00 Page 101
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General ....................................................................
IGNITION SYSTEM - MAINTENANCE PRACTICES ................................
Description and Operation ...................................................
Magneto Removal/Installation................................................
Magneto-to-Engine External Timing Adjustment................................
Magneto-to-EngineTiming Check.............................................

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Page
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Page

201
201
201
204
204

IGNITION SWITCH - INSPECTION/CHECK........................................
Description .................................................................
Tools, Equipment and Materials ..............................................
ACS Ignition Switch Inspection and Lubrication ................................

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Page
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601
601
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601

CONTENTS
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
IGNITION SYSTEM - GENERAL
1.

Scope
A.

2.

This chapter covers the ignition system used on the 10-360 L2A engine.

Tools, Equipment and Materials
NOTE:

Refer to the following table for tools, equipment and material used throughout the chapter.

NAME

NUMBER

MANUFACTURER

USE

Luberex Grease

10-1206

Cessna Aircraft Company
Cessna Parts Distribution
Department 701, CPD
25800 East Pawnee
Wichita, KS 67218-5590

To lubricate ignition
switch components.

Ignition Switch
Parts Kit

A3770

Cessna Aircraft

To rebuild ignition switch.

3.

Definition
A.

This chapter contains two sections on the ignition system. The first section provides a troubleshooting
chart to aid in identifying common problems which may occur in the ignition system. The second
section contains maintenance practices for the ignition system.

© Cessna Aircraft Company

74-00-00
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
IGNITION SYSTEM - TROUBLESHOOTING

1.

General
A.

The following chart has been provided to aid maintenance technicians in system troubleshooting.
This chart should be used in conjunction with Chapter 71, IO-360-L2A - Troubleshooting to provide
a comprehensive look at solutions to engine problems. For information beyond the scope of this
chapter, refer to applicable engine and ignition system manuals and publications listed in Introduction
- List of Supplier Catalogs.

TROUBLE

PROBABLE CAUSE

REMEDY

ENGINE WILL NOT START

Defective ignition switch.

Check switch continuity.
Replace if defective.

Spark plugs defective,
improperly gapped or fouled
by moisture or deposits.

Clean, regap and test plugs.
Replace if defective.

Defective ignition harness.

If no defects are found by a
visual inspection, check with
a harness tester. Replace
defective parts.

Magneto "P" lead grounded.

Check continuity. "P" lead
should not be grounded in the
ON position, but should be
grounded on OFF position.
Repair or replace "P" lead.

Failure of impulse coupling.

Impulse coupling pawls should
engage at cranking speeds.
Listen for loud clicks as impulse
couplings operate. Remove
magnetos and determine cause.
Replace defective magnetos.

Defective magneto.

Refer to Ignition System Maintenance Practices.

Broken drive gear.

Remove magneto and check
magneto and engine gears.
Replace defective parts. Make
sure no pieces of damaged
parts remain in engine, or
engine disassembly will be
required.

Spark plugs defective,
improperly gapped or fouled
by moisture or deposits.

Clean, regap and test plugs.
Replace if defective.

Defective ignition harness.

If no defects are found by a
visual inspection, check with
a harness tester. Replace
defective parts.

ENGINE WILL NOT IDLE
OR RUN PROPERLY.

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MODEL 172
MAINTENANCE MANUAL
TROUBLE

PROBABLE CAUSE

REMEDY

Defective magneto.

Refer to Ignition System Maintenance Practices.

Impulse coupling pawls
remain engaged.

Listen for loud clicks as impulse
coupling operates. Remove
magneto and determine cause.
Replace defective magneto.

Spark plugs loose.

Check and install properly.

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MODEL 172

MAINTENANCE MANUAL
IGNITION SYSTEM - MAINTENANCE PRACTICES
1.

Description and Operation
A.
B.

C.

2.

The engine uses two Unison/Slick 4371 series, impulse-coupled magnetos to fire two spark plugs in
each cylinder.
For complete description, operation, troubleshooting, maintenance, overhaul and lubrication
requirements of the magnetos, refer to the Lycoming Direct Drive Engine Overhaul Manual, Lycoming
Operators Manual, Lycoming Service Instruction 1437 and the Unison 4300/6300 Series Magneto
Maintenance and Overhaul Manual.
For the inspection time requirements of the magnetos, refer to Chapter 5, Inspection Time Limits. For
the inspection procedures, refer to the Unison 4300/6300 Series Magneto Maintenance and Overhaul
Manual.

Magneto Removal/Installation
NOTE:
A.

The removal and installation for each magneto is typical.

Remove the Magneto (Refer to Figure 201).
(1) Remove the engine cowl. Refer to Chapter 71, Engine Cowl - Maintenance Practices.
WARNING: MAKE SURE THAT EACH MAGNETO P LEAD IS GROUNDED.
WARNING: BEFORE YOU ROTATE THE PROPELLER REMOVE A MINIMUM
OF ONE SPARK PLUG FROM EACH CYLINDER TO PREVENT
THE START OF THE ENGINE.
(2) Remove the screws that attach the high tension outlet cover to the magneto.
(3) Disengage the high tension cover from the magneto.
(4) For a reference point when you install the magneto, turn the propeller in the normal direction
until each impulse coupling releases near Top Dead Center (TDC) on the number one cylinder
compression stroke.
NOTE:

You will hear a click sound from the impulse couplings when they release.

(5) The crankshaft position can be found by the marks on the front or aft face of the starter ring gear
support. Refer to the Lycoming Service Instruction 1437 or latest revision for more instructions.
(a) When you use the marks on the front face of the ring gear, they must be aligned with the
small hole that is found at the two o'clock position on the front face of the starter housing.
(b) When you use the marks on the aft face of the ring gear, they must be aligned with the
engine case parting line.
(6) Turn the propeller in the opposite direction of the normal propeller operation to approximately
30 degrees BTDC (Before Top Dead Center) on the number one cylinder compression stroke.
(7) Turn the propeller in the normal direction to 25 degrees BTDC on the number one cylinder
compression stroke.
(8) Disconnect the P lead and ground wire from the magneto.
(9) Examine the magneto angle to help make sure you put it in the same position for installation.
(10) Remove the nuts, washers and clamps that attach the magneto to the engine housing.
(11) Remove the magneto from the housing.
B.

Install the Magneto (Refer to Figure 201).
(1) Apply a small quantity of silicone grease such as DC4 to each side of the new magneto base
gasket, which will help future timing adjustments.
(2) Make sure the magneto drive gear is installed correctly, the nut torqued correctly and the cotter
pin is installed. Refer to the Lycoming Service Instructions 1437 or latest revision and the Unison
4300/6300 Magneto Maintenance and Overhaul Manual Instructions.

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MAINTENANCE MANUAL

B1421

VACUUM
PUMP

REAR
RAFFLE

MAGNETOS
ENGINE
DRIVEN
FUEL PU

VACUUM
PUMP (NOT
-USTRATED)

TAIL
PIPE

FUEL
STRAINER
DRAIN

0550T1007

Magneto Installation
Figure 201 (Sheet 1)

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MODEL 172

MAINTENANCE MANUAL
CAUTION: MAKE SURE YOU REMOVE THE T-118 TIMING PIN
IMMEDIATELY AFTER YOU ATTACH
THE MAGNETO TO
THE ACCESSORY CASE AND BEFORE THE MAGNETO OR
PROPELLER IS TURNED.
(3) Insert the T-118 timing pin into the L timing hole in the magneto distributor block.
(4) Turn the magneto rotor in the opposite of normal direction until the timing pin is engaged fully
into the distributor gear.
(a) If the magneto rotor does not move freely and the pin will not go into the hole in the gear,
the pin has hit the pointer on the gear.
(b) Pull the pin out far enough to continue to turn the magneto freely in the opposite direction
of normal movement until the pointer has passed the pin, then insert the pin.
1
Turn the magneto rotor until the pin engages the gear.
(5) Do a check of the crankshaft to make sure the propeller has not moved and is still set in position
with the number one cylinder at 25 degrees BTDC (Before Top Dead Center) on the compression
stroke.
(6) If the propeller as been turned and only one magneto was removed, it will be necessary to
engage the impulse coupling on the magneto that is installed, and establish the crankshaft
position. Refer to step 2.A.(4) thru 2.A.(7) before you continue.
(7) With the number one cylinder at 25 degrees BTDC on the compression stroke, do the steps that
follow.

CAUTION:

MAKE SURE YOU REMOVE THE T-118 TIIVIING PIN
IMMEDIATELY AFTER YOU ATTACH THE MAGNETO TO
THE ACCESSORY CASE AND BEFORE THE MAGNETO
OR PROPELLER IS TURNED.

(a)
(b)

(8)
(9)
(10)
(11)
(12)
(13)
(14)

Install the magneto with the new base gasket and the T-118 timing pin in position.
Engage the magneto drive gear with the engine gear, in a position that will give a range of
magneto timing adjustments in each direction.
(c) Hold the magneto in position against the accessory case and install the nuts, flat washers,
clamps and new lock washers.
(d) Finger tighten each nut by hand.
(e) Remove the timing pin.
Before you continue, you must adjust the magneto timing. Refer to Magneto-to Engine External
Timing Adjustment.
With the magneto set in position, first tighten each nut to 8 foot-pounds (10 N.m).
Tighten each nut from one side to another, to a torque of 17 foot-pounds (23 N.m).
Connect the P lead to the magneto.
Attach a ground wire to the magneto.
Attach the high tension outlet cover to the magneto.
Tighten the P lead nut to a torque of 13 to 15 inch-pounds (17 to 20 N.m).

CAUTION: MAKE SURE YOU REMOVE THE T-118 TIMING PIN BEFORE
THE MAGNETO OR PROPELLER IS TURNED.
(15) Install the spark plugs.
(16) Install the cowl. Refer to Chapter 71, Engine Cowl - Maintenance Practices.
(17) Complete a engine preflight operational check of the ignition system. Refer to the Pilot's
Operating Handbook.

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MAINTENANCE MANUAL

3.

Magneto-to-Engine External Timing Adjustment
A.

Adjust the Magneto-to-Engine Timing (Refer to Figure 201).
NOTE:

(1)

(2)
(3)
(4)
(5)
(6)

The Magneto-to-Engine timing can be adjusted a maximum total of 0.125 inch (3.17 mm)
movement from the original factory position, or between each internal timing adjustment.
The external timing movement of 0.125 inch (3.17 mm) approximately equals 5 degrees of
internal timing change.

Before the first field adjustment of external timing, the magneto and accessory case must be
indexed as necessary to monitor external timing adjustments.
(a) The magneto must be removed and internal timing adjusted in accordance with Unison
4300/6300 Series Aircraft Magnetos Maintenance and Overhaul Instructions Form
L-1363B or latest revision, when the external timing adjustments collect up to 0.125 inch
(3.17 mm) movement change.
Make sure the ignition is in the OFF position.
Remove the engine cowl. Refer to Chapter 71, Engine Cowl - Maintenance Practices.
Remove a minimum of one spark plug from each cylinder.
Make sure that cylinder number one is at 25 degrees BTDC (Before Top Dead Center) on the
compression stroke.
Connect a standard aircraft magneto timing light between a acceptable engine ground and the
P lead terminal of the magneto.
NOTE:

(7)
(8)

Most standard aircraft magneto timing lights show open points with a Light On
condition and/or a signal that you can hear.

Loosen the mount clamps that attach the magneto to the accessory case so that the magneto
will turn on the accessory case.
Turn the ignition switch to the BOTH position.
(a) Look at the magneto from the aft side of the engine.
1
If the timing light is luminated, turn the magneto frame clockwise until the timing light
shuts off.
2
Turn the magneto frame counter-clockwise until the timing light comes on, which
shows that the contact breaker points are open.

CAUTION : DO NOT TORQUE THE NUTS MORE THAN 17 FOOT-POUNDS
(23 N.m.) OR THE MOUNTING FLANGE CAN CRACK.
(9) With the magneto set in position, first tighten each nut to 8 foot-pounds (10 N.m).
(10) Tighten each nut from one side to another, to a torque of 17 foot-pounds (23 N.m).
(11) Complete a check of the magneto timing to make sure it has not changed. Refer to Magnetoto-Engine Timing Check.
4.

Magneto-to-EngineTiming Check
A.

Complete a Check of the Magneto-to-Engine Timing (Refer to Figure 201).
(1) Make sure the ignition is in the OFF position.
(2) Remove the engine cowl. Refer to Chapter 71, Engine Cowl - Maintenance Practices.
(3) Remove a minimum of one spark plug from each cylinder.
(4) Connect a standard aircraft magneto timing light between an acceptable engine ground and the
P lead terminal of the magneto.
NOTE:
(5)

Most standard aircraft magneto timing light indicate open points with a Light On
condition and/or an signal that you can hear.

Turn the ignition switch to the BOTH position.

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MODEL 172
MAINTENANCE MANUAL
(6) Turn the propeller in the normal direction of movement until each impulse coupling releases as
the number one cylinder moves near TDC (Top Dead Center) on the compression stroke.
NOTE:

You will hear a click sound from the impulse couplings when they release.

(7) Turn the propeller in the opposite direction of normal movement to approximately 30 degrees
BTDC (Before Top Dead Center) on the number one cylinder compression stroke.
(8) Slowly turn the propeller in the normal direction of movement until the timing light comes on.
(9) Examine the crankshaft to make sure it is in the correct position.
NOTE:

The timing light must come on at 25 degrees BTDC with the number one cylinder on
the compression stroke.

(10) If the crankshaft is not in the correct position you will have to make an adjustment. Refer to
Magneto-to-Engine External Timing Adjustment.
(11) Turn the ignition switch to the OFF position.
(12) Install the spark plugs.
(13) Install the ignition leads on the spark plugs.
(14) Install the cowl. Refer to Chapter 71, Engine cowl - Maintenance Practices.
(15) Complete a engine preflight operational check of the ignition system. Refer to the pilot's
operating handbook.

74-10-00
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
IGNITION SWITCH - INSPECTION/CHECK
1.

Description
A.

2.

Tools, Equipment and Materials
A.

3.

The following inspection and lubrication procedures are designed for the ACS brand ignition switch
and should be accomplished every 2000 hours.

Refer to Ignition System - General for a list of required tools, equipment and materials.

ACS Ignition Switch Inspection and Lubrication
NOTE:
A.

Refer to Figure 601 for the following steps.

Switch Removal.
(1) Disconnect battery.
(2) Remove switch assembly from instrument panel by loosening locknut on the forward side of
panel and removing decorative nut on aft side of panel.
NOTE:

Wiring need not be removed from posts of switch if wiring is of sufficient length to allow
switch assembly to be moved to a position where disassembly can be accomplished.
If wiring is to be disconnected, tag or mark wires for reinstallation.

B.

Switch Disassembly.
(1) Hold switch body in position shown in Figure 601.
(2) Remove screws and washers.
(3) Lift terminal board assembly from body, being careful not to lose springs and cups.

C.

Switch Cleaning.
(1) Clean switch contacts and the three movable contact cups using alcohol on a cotton tip swab.

D.

Switch Inspection.
(1) Inspect movable contact cups and switch contacts on the terminal board assembly for excessive
wear or corrosion and for loose contacts or terminals. If the silver plating on the contact cups
is worn through to the brass material, or they are burned or pitted from arcing or are corroded,
they should be replaced. If the contacts on the contact block exhibit any of the above conditions
or the terminals are loose, the terminal board assembly should be replaced.

E.

Switch Reassembly.
(1) Apply a thin coating of Luberex 10-1206 lubricant to switch contacts and the three movable
contact cups. Ensure all contact areas are covered with lubricant.
(2) Reassemble switch using new parts, if required. Ensure that cups and springs are positioned
in switch body so that no binding occurs. Secure terminal board assembly to switch body with
retained washers and screws.
(3) Mark switch with a dab of red paint on the terminal board retaining screws.
(4) If removed, reconnect wiring to backside of switch.
(5) Install switch in panel and secure using existing hardware.
(6) Reconnect battery and perform an operational check of the switch.

F.

Operational Check.
(1) Start engine. Refer to Model 172R Pilot's Operating Handbook and FAA Approved Airplane
Flight Manual.
(2) Check magnetos for normal engine RPM drop.
(3) Verify that both magnetos are grounded when switch is in the OFF position.
(a) Reduce engine RPM to idle, and turn switch to the OFF position. Engine should quit
immediately, signifying that both magnetos have been grounded through the ignition switch.
(4) After engine stops, move mixture control to idle cutoff position.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1796

SWITCH
CONTACTS

TERMINAL
BOARD
ASSEMBLY
SWITCH
LOCKWASHE

SCREW

DETAIL

A

0510T1007
A0558T1004

ACS Ignition Switch Inspection/Lubrication
Figure 601 (Sheet 1)

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CHAPTER

ENGINE CONTROLS

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

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Number

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL

CONTENTS
ENGINE CONTROLS - GENERAL ................................................

Scope. .....................................................................
Definition ...................................................................
THROTTLE CONTROL - MAINTENANCE PRACTICES .............................
General ...................................................................
Throttle Control Removal/Installation.........................................
Throttle Control Adjustment/Test..............................................
Throttle Control Inspection/Check ............................................
FUEL MIXTURE CONTROL - MAINTENANCE PRACTICES.........................
General ....................................................................

Fuel Mixture Control Removal/Installation .....................................
Fuel Mixture Control Adjustment/Test .........................................
Fuel Mixture Control Inspection/Check ........................................

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ENGINE CONTROLS - GENERAL

1.

Scope
A.

2.

This chapter describes those controls used to regulate engine power.

Definition
A.

This Chapter is divided into sections to aid maintenance technicians in locating information.
Consulting the Table of Contents will further assist in locating a particular subject. A brief description
of the sections follows:
(1) The section on throttle control describes the throttle handle, cable and linkage.
(2) The section on fuel mixture control describes the mixture handle, cable and linkage.
(3) Both sections include removal/installation, rigging and inspection requirements.

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MAINTENANCE MANUAL
THROTTLE CONTROL - MAINTENANCE PRACTICES
1.

General
A.

The throttle control is the push-pull type that incorporates a knurled friction knob, which prevents
vibration induced "creeping" of the control. The ball bearing-type rod end on the throttle is secured to
the engine with a predrilled AN bolt, a castellated nut and a cotter pin.
NOTE:

2.

Steel AN bolts with an undrilled shank are identified with an "A" suffix (AN3-6A). A steel
bolt of the same size, with the shank drilled for castellated nut and cotter pin is identified
as AN3-6. Aluminum AN bolts shall not be used in this application.

B.

When adjusting the throttle control, it is important to check that throttle control slides smoothly
throughout its full range of travel, that it locks securely with the friction lock and the throttle arm
operates through its full arc of travel. Do not lubricate throttle control. If excessive binding is noticed,
replace throttle control.

C.

Whenever engine controls are being disconnected, pay particular attention to the exact position, size
and number of attaching parts for re-connecting controls.

Throttle Control Removal/Installation
A.

B.

Remove Throttle Control (Refer to Figure 201).
(1) Remove engine cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Remove cotter pin, castellated nut, bolt and washers securing throttle control rod end to throttle
body arm.
(3) Remove clamp securing throttle control to engine mount.
(4) Remove throttle cable retaining nut and washer from forward side of firewall.
(5) Inside the cockpit/cabin area, remove throttle cable retaining nut and washer from forward side
of instrument panel.
(6) Carefully pull throttle control through firewall and instrument panel, and remove from airplane.
Install Throttle Control (Refer to Figure 201).
NOTE:

When installing throttle control, ensure that control is routed exactly as previously installed.
Ensure that no binding or preloading occurs from a too small bend radius.

(1)

Inside the cockpit/cabin area, carefully route throttle control rod end through instrument panel
and then place washer and retaining nut over rod end.
(2) Route throttle control rod end through firewall and position throttle control in instrument panel.
(3) Secure throttle control in instrument panel by tightening retaining nut against washer and
instrument panel.
NOTE:

To prevent damage to the instrument panel finish and markings, ensure the control
housing does not rotate against the instrument panel during installation.

(4) In the engine compartment, place washer and retaining nut over throttle control rod end and
secure against firewall.
(5) Attach throttle control rod end to throttle body with bolt, washers, castellated nut and cotter pin.
(6) Secure throttle control to engine mount with clamp.
(7) Adjust throttle control as required. Refer to Throttle Control Adjustment/Test.
(8) Install engine cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
3.

Throttle Control Adjustment/Test
A.

Check Throttle Control (Refer to Figure 201).
(1) Pull throttle control knob full out and check that idle stop on throttle body is contacted.
(2) Push throttle control knob full in and check that full power stop on throttle body is contacted.
(3) Do a check to make sure that the throttle has no less than 0.12-inch (3.18 mm) and no more
than 0.25-inch (6.35 mm) cushion at each stop.

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MAINTENANCE MANUAL

INSTRUMENT
PANEL
LOCKWASHEI
JAMNUT

FIREWAL

LOCKWASHER
/

THROTTLE ASSEMBLY

CASTELLATED
WA

DETAIL

A

0510T1007
0515T1005

Throttle Control Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B.

4.

(4) Work throttle control in and out several times to check for binding.
Adjust Throttle Control (Refer to Figure 201).
(1) Disconnect throttle control rod end from the throttle body.
(2) Loosen jam nut and adjust throttle control rod end to obtain desired setting.
(3) Tighten jam nut.
(4) Connect throttle control rod end to throttle body.

Throttle Control Inspection/Check
A.

Inspection of Throttle Control.
(1) The throttle control attachment to throttle body should be inspected in accordance with time
limits established in Chapter 5, Inspection Time Limits. Do a check of the bolt, castellated nut,
cotter pin, rod end, and rod end jam nut for security and condition.
(2) Do a check of the rod end witness hole for proper rod end engagement with the throttle control.
(3) Do a check to make sure that the throttle control slides smoothly throughout its full range of
travel, that it locks securely with the friction lock, and that the throttle arm operates through its
full arc of travel.

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MODEL 172
MAINTENANCE MANUAL
FUEL MIXTURE CONTROL - MAINTENANCE PRACTICES
1.

General
A.

The mixture control is the push-pull type that incorporates a threaded vernier mechanism for fine
adjustment. The ball bearing rod end on the mixture control is secured to the engine with a predrilled
AN bolt, a castellated nut and a cotter pin.
NOTE:

2.

Steel AN bolts with an undrilled shank are identified with an 'A' suffix (AN3-6A). A steel bolt
of the same size, with the shank drilled for castellated nut and cotter pin is identified as
AN3-6. Aluminum bolts and undrilled bolts must not be used in this application.

B.

When adjusting the fuel mixture control, it is important to check that fuel mixture control slides smoothly
throughout its full range of travel, that it adjusts through its full vernier range and the mixture arm
operates through its full arc of travel. Do not lubricate fuel mixture control. If excessive binding is
noticed, replace fuel mixture control.

C.

Whenever engine controls are being disconnected, pay particular attention to the exact position, size
and number of attaching parts as noted when connecting controls.

Fuel Mixture Control Removal/Installation
A.

B.

Remove Fuel Mixture Control (Refer to Figure 201).
(1) Remove engine cowling. Refer to Chapter 71, Cowling - Removal/Installation.
(2) Remove cotter pin, nut, bolt and washers securing mixture control rod end to throttle body
mixture arm.
(3) Remove clamp securing fuel mixture control to mixture control bracket.
(4) Remove fuel mixture control retaining nut and washer from forward side of firewall.
(5) In the cockpit/cabin area, remove mixture control retaining nut and washer from forward side of
instrument panel.
(6) Carefully pull mixture control through firewall and instrument panel, and remove from airplane.
Install Fuel Mixture Control (Refer to Figure 201).
NOTE:

When installing mixture control ensure that control is routed exactly as previously installed.
Ensure that no binding or preloading occurs from a too small bend radius.

(1) In the cabin/cockpit area, carefully route fuel mixture control through instrument panel, and then
place washer and retaining nut over fuel mixture control rod end.
(2) Route fuel mixture control through firewall.
(3) Secure fuel mixture control in instrument panel by tightening retaining nut against washer and
instrument panel.
NOTE:

To prevent damage to the instrument panel finish and markings, ensure the control
housing does not rotate against the instrument panel during installation.

(4) In the engine compartment, place washer and retaining nut over fuel mixture control rod end
and secure against firewall.
(5) Attach mixture control rod end to throttle body mixture arm with bolt, washers, nut and cotter pin.
(6) Secure fuel mixture control to mixture control bracket with clamp.
(7) Install Engine Cowling. Refer to Chapter 71, Cowling - Removal/Installation.
3.

Fuel Mixture Control Adjustment/Test
A.

Check Fuel Mixture Control.
(1) Push fuel mixture control full in and verify that mixture arm on throttle body is fully open (rich).
(2) Pull fuel mixture control full out and verify that mixture arm on throttle body is fully closed (lean).
(3) Do a check to make sure that the fuel mixture control has no less than 0.12-inch (3.18 mm) and
no more than 0.25-inch (6.35 mm) cushion at each stop.
(4) Work fuel mixture control in and out several times to check for binding.
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MAINTENANCE MANUAL

INSTRUMENT
PANEL

ITH

JAMNUTS
WITH
WASHERS

ER

FIREW

SUPPORT ARM
/

MIXTURE
CABLE

BOLT

NUT

LARGE WA
WA

PIN

DETAIL A
0510T1007
A0515T1008

Fuel Mixture Control
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL
B.

I
I
4.

Adjust Fuel Mixture Control.
(1) Disconnect fuel mixture control rod end from throttle body.
(2) Loosen jam nut and adjust rod end to obtain desired setting. The witness hole in the rod end
must be covered with the mixture cable threads.
(3) Tighten jam nut.
(4) Connect rod end to throttle body. If necessary, you can reposition the mixture control housing in
the mixture control bracket clamp.

Fuel Mixture Control Inspection/Check
A.

Inspect Fuel Mixture Control.
(1) The mixture control attachment to the throttle body should be inspected in accordance with time
limits established in Chapter 5, Inspection Time Limits. Check bolt, castellated nut, cotter pin
and rod end for security and condition. The witness hole in the rod end must be covered with the
mixture cable threads. Check that fuel mixture control slides smoothly throughout its full range
of travel, that it adjusts through its full vernier range and the mixture arm operates through its
full arc of travel.

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CHAPTER

ENGINE INDICATING

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
PAGE

DATE

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Jul 1/2007

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CHAPTER-SECTION-SUBJ ECT
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77-Table of Contents

77
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-

LIST OF EFFECTIVE PAGES

Page 1of 1
Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

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Date Removed

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

CONTENTS
ENGINE INDICATING - GENERAL.........................
Scope....................................
Definition ..................................
TACHOMETER - MAINTENANCE PRACTICES...................
Description and Operation ..........................
Tachometer and Drive Cable Removal/Installation................
Tachometer Sending Unit Removal/Installation .................
ENGINE TEMPERATURE - DESCRIPTION AND OPERATION............
Description .................................
Operation..................................
ENGINE TEMPERATURE INDICATING SYSTEM - MAINTENANCE PRACTICES.
Description and Operation ..........................
EGT Indicator Removal/Installation ......................
EGT Probe Removal/Installation........................
EGT Probe Removal/installation (Airplanes with Garmin G1000).........
CHT Probe Removal/Installation........................
ENGINE/AIRFRAME UNIT - MAINTENANCE PRACTICES..............
General...................................
Troubleshooting ...............................
GEA 71 Engine/Airframe Unit Removal/installation ...............

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Page
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Page 1of 1
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
ENGINE INDICATING - GENERAL
1.

Scope
A.

2.

This chapter describes those components used to measure and indicate engine output.

Definition
A.

This chapter is divided into sections to aid maintenance technicians in locating information. Consulting
the Table of Contents will further assist in locating a particular subject. A brief description of the
sections follows:
(1) The section on tachometer describes the instrument used to measure engine RPM.
(2) The section on exhaust gas temperature describes the system used to monitor and measure
engine temperature.

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MAINTENANCE MANUAL
TACHOMETER

-

MAINTENANCE PRACTICES

1.Description and Operation
A.

B.

2.

On airplanes with standard avionics, the engine speed (RPM) is measured by an indicator in the
cockpit. The tachometer maintenance practices give removal and installation procedures for the
tachometer and drive cable.
On airplanes with Garmin G1000, the engine speed (RPM) is measured by the tachometer sending
unit and changed to an electrical signal. The Garmin Control Display Units (CDU) display the engine
speed. The tachometer maintenance practices give removal and installation procedures for the
tachometer sending unit.

Tachometer and Drive Cable Removal/installation
NOTE:
A.

B.

3.

Airplanes without Garmin G1000 have a tachometer and drive cable.

Remove the Tachometer and Drive Cable (Refer to Figure 201).
(1) Disconnect the drive cable from the tachometer.
(2) Disconnect the electrical connector (J1014) from the tachometer.
(3) Remove the screws that attach the tachometer to the instrument panel and remove the
tachometer.
(4) Remove the upper engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.
(5) Disconnect the drive cable at the rear of the accessory case.
(6) Remove the two screws that attach the firewall shield to the firewall.
(7) Remove the drive cable through the firewall.
Install the Tachometer and Drive Cable (Refer to Figure 201).
(1) Install the drive cable through the firewall.
(2) Connect the drive cable to the accessory case housing.
(3) Install the firewall shield to the firewall with the screws.
(4) Install the tachometer to the instrument panel with the screws.
(5) Connect the electrical connector (JI014) to the tachometer.
(6) Connect the drive cable to rear of the tachometer.
(7) Install the upper engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.

Tachometer Sending Unit Remova~l/nstallation
NOTE:

Airplanes with Garmin G1000 have a tachometer sending unit.

A.

Remove the Tachometer Sending Unit (Refer to Figure 202).
(1) Make sure the MASTER switch is in the off position.
(2) Remove the side cowl. Refer to Chapter 71, Cowl - Maintenance Practices.
(3) Disconnect the electrical connector.
(4) Loosen the knurled nut.
(5) Remove the tachometer sending unit from the airplane.

B.

Install the Tachometer Sending Unit (Refer to Figure 202).
(1) Put the tachometer sending unit in position on the airplane.
(2) Tighten the knurled nut.
(3) Connect the electrical connector.
NOTE:

If irregular tachometer indications have occurred, the use of Stabilant 22 contact
enhancer on the electrical connector (PN025) can possibly decrease the occurrence

of these indications.
(4) Install the side cowl. Refer to Chapter 71, Cowl

-

Maintenance Practices.

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91799

A

TACHOM ETER
DRIVE CABLE

INSTRUMENT
PANEL

El

DETAIL A

(WITHOUT GARMIN G1000)

as51rOT1D0
A0514T1 018

Tachometer Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL

W3M30

A

. -

VIEw

A-A

TACHOMETER
0CK1F`%hI~rf1 1 WMI

ELECTRICAL
CON NECTOR
(PN025)

DETAIL A

(WITH GARMIN G1 000)

051 OTI 007
AAO55OTl 008
A0l758T1 003

Tachometer Sending Unit Installation
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL
ENGINE TEMPERATURE - DESCRIPTION AND OPERATION
1.

Description
A.

2.

The section that follows has removal and installation procedures for the system which will show
different temperatures in the engine. The system that shows the temperature for the engine includes
the indicators and probes for the Cylinder Head Temperature (CHT) and Exhaust Gas Temperature
(EGT).

Operation
A.

The EGT system is used to measure the temperature of the exhaust gas. The measurement gives an
indication of the fuel/air mixture for the pilot. The system has one indicator installed in the instrument
panel, which gives the two functions that show the EGT and CHT information. A probe installed in
the exhaust and a probe installed in a cylinder, send the temperature information to the EGT/CHT
indicator. On airplanes with Garmin G1000, each cylinder has EGT and CHT probes.

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MAINTENANCE MANUAL
ENGINE TEMPERATURE INDICATING SYSTEM - MAINTENANCE PRACTICES
1.

Description and Operation
A.

2.

Maintenance of the engine temperature system includes the removal and installation of the different
components.

EGT Indicator Removal/Installation
NOTE:

3.

The procedures that follow are for airplanes without Garmin G1000.

A.

Remove the EGT Indicator (Refer to Figure 201).
(1) Get access to the forward side of the indicator.
(2) Disconnect the electrical connector from the indicator.
(3) Remove the screws that attach the indicator to the instrument panel and remove the indicator
from the airplane.

B.

Install the EGT Indicator (Refer to Figure 201).
(1) Put the indicator in the instrument panel and attach with the screws.
(2) Connect the electrical connector to the indicator.

EGT Probe Removal/Installation
NOTE:
A.

The procedures that follow are for airplanes without Garmin G1000.

Remove the EGT Probe (Refer to Figure 201).
(1) Remove the engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.

CAUTION: Make sure that the exhaust system and engine are cool before you
remove the probes.
(2)
(3)
(4)
B.

4.

Cut the tie strap that attaches the electrical connectors (JN006) and wire.
Disconnect the probe at the electrical connector.
Remove the probe from the muffler tailpipe.

Install the EGT Probe (Refer to Figure 201).
(1) Install the probe to the muffler tailpipe.
(2) Tighten the screw for the clamp.
(3) Attach safety wire to the EGT probe clamp and screw. Refer to Chapter 20, Safetying Maintenance Practices.
(4) Connect the probe at the electrical connector (JN006).
(5) Attach the electrical connector and wire with the tie straps.
(6) Install the engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.

EGT Probe Removal/Installation (Airplanes with Garmin G1000)
A.

Remove the EGT Probe (Refer to Figure 202 ).
NOTE:

The EGT probe is welded to the clamp.

NOTE:

Airplanes with Garmin G1000 have an EGT probe at each cylinder.
installation of the EGT probes are typical.

(1)

Removal and

Remove the engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.

CAUTION: Make sure the exhaust system and engine are cool before the
probes are removed.
(2)
(3)

Disconnect the electrical connectors.
Cut and remove the safety wire from the EGT probe clamp and screw.

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A,
A
A

A

VIEW A-A

PROBE

DETAIL

A
EGT INDICATOR
INSTRUMENT PANEL

NUT
LOCK WASHI
SCREW

DETAIL

B

0510T1007
AA0518T1049
A07181037
B0518T1048

EGT Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL

B3768

BOLT

SAFETY
WIRE
I
I

DETAIL

C
C0755T1001

EGT Installation
Figure 201 (Sheet 2)

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MAINTENANCE MANUAL
B3831

VIEW A-A
AIRPLANES WITH GARMIN G1000

0510T1007
A0555T1009

EGT/CHT Probe Location
Figure 202 (Sheet 1)

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MAINTENANCE MANUAL

(4)

(5)

B.

5.

Loosen the clamp screw.
Remove the clamp with the attached probe from the exhaust pipe.

Install the EGT Probe (Refer to Figure 202).
(1) Attach the clamp with the EGT probe to the exhaust pipe.
(2) Tighten the screw on the clamp
(3) Attach safety wire to the EGT probe clamp and screw.
(4) Connect the electrical connectors.
(5) Attach the connectors together with a tie strap.
(6) Install the engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.
(7) Make sure the EGT probe operates correctly. Refer to the Pilot's Operating Handbook.

CHT Probe Removal/Installation
A.

Remove the CHT Probe (Refer to Figure 202).
NOTE:

The CHT probes use a bayonet-style connector.

NOTE:

Airplanes with Garmin G1000 have a CHT probe for each cylinder.
installation of the CHT probes is typical.

Removal and

(1) Remove the engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.

CAUTION: Make sure the exhaust system and engine are cool before the
probes are removed.
(2) Remove the terminal nut.
(3) Disconnect the terminal from the CHT probe.
(4) Turn the CHT probe to remove from the cylinder head.
B.

Install the CHT Probe (Refer toFigure 202).
(1) Install the CHT probe into the cylinder head.
(2) Connect the terminal on the CHT probe.
(3) Install the terminal nut.
(4) Install the engine cowl. Refer to Chapter 71, Engine Cowling - Maintenance Practices.
(5) Make sure the CHT operates correctly. Refer to the Pilot's Operating Handbook.

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MAINTENANCE MANUAL
ENGINE/AIRFRAME UNIT - MAINTENANCE PRACTICES
1.

2.

General
A.

On airplanes with Garmin G1000, the GEA 71 Engine/Airframe Unit is a microprocessor-based Line
Replaceable Unit (LRU) that receives and processes signals from the engine and airframe sensors.
The GEA 71 Engine/Airframe Unit speaks directly with the GIA 63 Integrate Avionics Units.

B.

Maintenance practices give procedures for the removal and installation of the GEA 71 Engine/Airframe
Unit. The unit is in the cockpit forward of the instrument panel.

Troubleshooting
A.

3.

GEA 71 Engine/Airframe Unit Removal/Installation
A.

|

I

For troubleshooting procedures, refer to the Garmin G1000 Line Maintenance Manual.

B.

Remove the Engine/Airframe Unit (Refer to Figure 201).
(1) Put the MASTER switch in the off position.
(2) Put the AVIONICS switch in the off position.
(3) Remove the Multi-Function Display (MFD). Refer to Chapter 34, Control Display Unit Maintenance Practices.
(4) Release the engine/airframe unit handle.
(a) For units with a Phillips screw, loosen the screw to unlock the unit handle.
(b) For units with a D-Ring, push on the D-Ring and turn it 90 degrees counterclockwise to
unlock the unit handle.
(5) Move the lever up to disengage the locking stud with the dogleg slot in the mounting rack.
(6) Remove the unit from the mounting rack.
Engine/Airframe Unit Installation (Refer to Figure 201).
NOTE:

If a new unit is installed, it is necessary to load the software and configuration.

CAUTION: Make sure the unit goes into position without resistance. Damage to the
connectors, unit, or mounting rack will occur if the unit is pushed into
position with force.
NOTE:
(1)
(2)

The unit must be in position in the mounting rack to let the locking stud engage the channel.

Make sure the electrical connector and connector pins have no damage.
(a) Replace the electrical connector or connector pins if applicable. Refer to the Wiring
Diagram Manual and the Garmin G1000 Line Maintenance Manual.
Carefully put the unit in position in the mounting rack.

CAUTION: Make sure the lever moves without resistance. Damage to the unit
will occur if the lever is pushed into position with force.
(3)
(4)

(5)
(6)
(7)

Push the lever down toward the bottom of the unit to engage the locking stud with the dogleg
slot in the mounting rack.
(a) If the lever does not go down, adjust the backplate while the unit is engaged.
Lock the handle in position.
(a) For units with a Phillips screw, tighten the screw to lock the unit handle.
(b) For units with a D-Ring, push on the D-Ring and turn it 90 degrees clockwise to lock the
unit handle.
Install the MFD. Refer to Chapter 34, Control Display Unit - Maintenance Practices.
If a new unit is installed, load the software and configuration. Refer to the Garmin G1000 Line
Maintenance Manual.
Do a check to make sure that the engine/airframe unit operates correctly. Refer to the Garmin
G1000 Line Maintenance Manual.

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''

CESSNA AIRCRAFT COMPANY

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MAINTENANCE MANUAL

NOTE:

MULTI-FUNCTION DISPLAY
NOT SHOWN.

i

(
ENGINE/
AIRFRAME

0510T1007
A0518T1106

DETAIL A
Engine/Airframe Unit Removal/Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL
(7) Do a check to make sure the engine interface unit operates correctly. Refer to the Garmin G 1000
Line Maintenance Manual.

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CHAPTER

EXHAUST

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

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DATE

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MAINTENANCE MANUAL

CONTENTS
EXHAUST - GENERAL

.........

.........

...........

...........................

Scope and Definition ........................................................
EXHAUST SYSTEM - MAINTENANCE PRACTICES ......... .....................
Description .................................................................
Exhaust System Removal/Installation .........................................
Muffler Inspection ...........................................................

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
EXHAUST - GENERAL
1.

Scope and Definition
A.

This chapter is comprised of a single section on the exhaust system. The section details removal,
installation and testing procedures for the exhaust system.

© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL
EXHAUST SYSTEM - MAINTENANCE PRACTICES
1.

Description
A.

B.
2.

3.

The exhaust system consists of an exhaust pipe (riser) from each cylinder to the muffler with a single
tailpipe which routes exhaust gases out through the lower cowling area. The muffler is located beneath
the engine, and is enclosed by a shroud which captures radiated exhaust heat. This heated air is then
ducted to the airplane cabin through flexible hoses.
Maintenance practices for the exhaust system consist of removal, installation and testing of the
exhaust system for leaks.

Exhaust System Removal/Installation
A.

Remove Exhaust System (Refer to Figure 201).
(1) Remove engine cowling. Refer to Chapter 71, Engine Cowling - Maintenance Practices.
(2) Loosen left front baffle to allow heat shroud inlet to clear baffle.
(3) Remove EGT probe.
(4) Disconnect flexible heat duct from heat shroud.
(5) Remove clamps securing risers to muffler.
(6) Remove nuts and washers securing risers to engine and remove risers/muffler as an assembly
from engine.
(7) Remove screws securing heat shroud to itself, and unwrap heat shroud from around muffler.
(8) Inspect muffler for leaks. Refer to Muffler Inspection below.

B.

Install Exhaust System (Refer to Figure 201).
(1) Wrap heat shroud around muffler and secure to itself using screws.
(2) Loosely install risers (4 total) to muffler using clamps.
(3) Install riser/muffler assembly to engine using new gaskets.
(4) Tighten risers 200-210 inch-pounds at engine, then tighten clamps connecting risers to muffler.
(5) Reconnect EGT probe.
(6) Reinstall engine cowling. Refer to Chapter 71, Engine Cowling - Maintenance Practices.

Muffler Inspection
NOTE:

The exhaust system must be thoroughly inspected at time intervals set forth in Chapter 5,
Inspection Time Limits, or anytime exhaust fumes are detected in the cabin.

WARNING: FAILURE TO INSPECT MUFFLER FOR LEAKS COULD RESULT IN
CARBON MONOXIDE ENTERING THE CABIN, LEADING TO SERIOUS
INJURY OR DEATH.
A.

Inspection Procedures.
NOTE:

If muffler shows signs of leaks or damage as indicated in steps 3.A.(1) thru 3.A.(3), it must
be replaced.

(1) Using a flashlight and mirror, examine the interior of the muffler, looking for cracks or general
deterioration.
(2) Using visual inspection, examine the exterior of muffler, looking for holes, cracks and burned
spots. Pay special attention to areas adjacent to welds and to exhaust gas deposits (which
indicate an exhaust leak).
(3) After visual inspection an air leak check should be made on the system as follows:
(a) Attach the pressure side of an industrial vacuum cleaner to the tail pipe opening, using a
rubber plug to effect a seal as required.
NOTE:

The inside of vacuum cleaner hose should be free of any contamination that
might be blown into the engine exhaust system.

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MODEL 172

MAINTENANCE MANUAL

B236

RISER
PICAL)

MUFFLER

CLAMP

HEAT
SHROUD

0555T2001

Exhaust System Installation
Figure 201 (Sheet 1)

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MAINTENANCE MANUAL
(b) With vacuum cleaner operating, all joints in the exhaust system may be checked by using
a soap and water solution and watching for bubbles. Forming of bubbles is considered
acceptable; if bubbles are blown away, system is not considered acceptable.
(4) Use a water test to determine muffler integrity:
(a) Seal openings in muffler using rubber expansion plugs.
NOTE:

One expansion plug should be adapted to allow for introduction of low-pressure
air into muffler.

(b) Using a pressure gauge or manometer, apply approximately 3.0 PSI, +0.5 or -0.5 PSI (6
inches mercury), to interior of muffler and submerge muffler into water. Any leaks will
appear as bubbles and can be readily detected.
(c) If any leaks are detected, the muffler must be removed from service and repaired or
replaced.
(d) If no defects are found, remove muffler from water, remove plugs and dry muffler with
compressed air.

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CHAPTER

OIL

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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Apr 7/2003

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Jan 2/2006

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Jan 3/2005

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Jan 2/2006

79-31-00

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Jan 3/2005

79-Title
79-List of Effective Pages
79-Record of Temporary Revisions
79-Table of Contents

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79 - LIST OF EFFECTIVE PAGES

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RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

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MODEL 172

MAINTENANCE MANUAL

CONTENTS
OIL - GENERAL ......................
...........................................
S cope......................................................................
Definition ...................................................................

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OIL COOLER - MAINTENANCE PRACTICES ....................................
General ....................................................................
Oil Cooler Removal/Installation...............................................

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OIL PRESSURE INDICATOR - TROUBLESHOOTING ..............................
General ....................................................................

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OIL PRESSURE INDICATOR - MAINTENANCE PRACTICES .......................
Description and Operation .................................................
Oil Pressure Indicator and Transducer Removal/Installation .....................
Low Oil Pressure Switch Removal/Installation .................................

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OIL TEMPERATURE INDICATOR - TROUBLESHOOTING ..........................
General ....................................................................

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OIL TEMPERATURE INDICATOR - MAINTENANCE PRACTICES ...................
Description and Operation ...................................................
Oil Temperature Sending Unit Removal/Installation.............................
Oil Temperature/Oil Pressure Indicator Removal/Installation ....................

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201
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CESSNA AIRCRAFT COMPANY

MODEL 1 72

MAINTENANCE MANUAL
OIL - GENERAL
1.

Scope
A.

2.

This chapter provides maintenance instructions for those components which distribute oil and which
indicate oil condition. For information beyond the scope of this material, refer to appropriate Textron
Lycoming Operator's and Overhaul Manuals, and to Chapter 71, IO-360-L2A - Troubleshooting.

Definition
A.

This chapter is divided into sections to assist maintenance personnel in locating specific information.
The following is a brief description of each section. For locating information within the chapter, refer
to the Table of Contents at the beginning of the chapter.
(1) The section on distribution provides information on removal and installation of the external oil
cooler.
(2) The section on indicating provides information on gauges, transducers and switches used to
indicate oil temperature and pressure.

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MODEL 172
MAINTENANCE MANUAL
OIL COOLER - MAINTENANCE PRACTICES
1.

General
A.

2.

This section provides maintenance instructions for removal and installation of the externally mounted
oil cooler.

Oil Cooler Removal/Installation
A.

Remove Oil Cooler (Refer to Figure 201).
(1) Remove upper cowling. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Label and disconnect inlet and outlet hoses leading into oil cooler.
(3) Remove bolts, washers and spacers securing oil cooler to back of engine baffles.

B.

Install Oil Cooler (Refer to Figure 201).
(1) Secure oil cooler to rear of engine baffles using bolts, spacers and washers.
(2) Attach inlet and outlet hoses to oil cooler.
(3) Run engine and check oil cooler for leaks.
(4) Install upper cowling. Refer to Chapter 71, Cowling - Maintenance Practices.

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

B1801

OIL
COOLER

HOSE

BOLT

CAP

DETAIL

A
0510T1007
A0550T1004

Oil Cooler Installation
Figure 201 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
OIL PRESSURE INDICATOR - TROUBLESHOOTING
1.

I

General
A.
B.

On airplanes with Garmin G1000, the oil pressure is shown on the Multi-Function Display (MFD).
Refer to the Garmin G1000 Line Maintenance Manual for GDU 1040 troubleshooting.
This section gives a troubleshooting chart and table to help find the problem that will not let the oil
pressure indicator system function correctly. To help with troubleshooting the oil pressure indicator,
refer to the Model 172 1996 and On Wiring Diagram Manual.
(1) The table that follows is to be used with the troubleshooting chart (refer to Figure 101).

CAUTION: Do not apply voltages that are more than the voltages shown in Table
101. Too much voltage can cause damage to the indicator.
CAUTION: Do not calibrate the oil pressure indicator without a calibrated pressure
source.
NOTE:

A test of the calibration for the oil pressure transducer (JN004) can be completed at a
facility that has a calibrated pressure source. Table 101 can be used to do a check of the
correct output of the transducer.

Table 101. Oil Pressure Values
Volts Output at 77°F (25°C)

Oil Pressure

1.03 volts +0.080 or -0.080 volts

20 psi

2.63 volts +0.080 or -0.080 volts

80 psi

3.57 volts +0.080 or -0.080 volts

115 psi

79-30-00
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MODEL 172

MAINTENANCE MANUAL

B1489

OIL PRESSURE INDICATOR (JI015)
DOES NOT OPERATE OR SHOWS
THE INCORRECT PRESSURE.

MAKE SURE THERE IS AIRPLANE BUS POWER AT
PIN 1 (PC001) AND PIN 9 (GI001) ON THE WIRE BUNDLE
SIDE OF THE INDICATOR (JI015). IF-

I
OK, MAKE SURE THERE IS ELECTRICAL
CONTINUITY FOR THE TWO WIRES
BETWEEN THE TRANSDUCER
CONNECTOR (JN004) AND THE
INDICATOR CONNECTOR (JI015). MAKE
SURE THE WIRES DO NOT HAVE A
SHORT TO GROUND. IF-

NOT OK, REPAIR OR REPLACE
THE APPLICABLE WIRING.

OK, MAKE SURE THERE IS GROUND
AT PIN A ON THE TRANSDUCER
CONNECTOR. IF-

NOT OK, REPAIR OR REPLACE
THE APPLICABLE WIRING.

OK, MAKE SURE THERE IS 5.00 VOLTS +0.10
OR -0.10 VOLTS BETWEEN PIN C ON THE
TRANSDUCER CONNECTOR AND GROUND. IF-

NOT OK, REPAIR OR REPLACE
THE APPLICABLE WIRING.

OK, APPLY A CALIBRATED DC VOLTAGE
SOURCE OF 5.00 VOLTS +0.10 OR -0.10 VOLTS
BETWEEN PIN C ON THE TRANSDUCER
CONNECTOR AND GROUND. THE INDICATOR
MUST SHOW THE PRESSURE GIVEN IN
TABLE 101. REFER TO TABLE 101. IF-

NOT OK, REPLACE THE
INDICATOR (JI015). REFER TO
OIL PRESSURE INDICATOR
REMOVAL/INSTALLATION.

NOT OK, REPLACE THE INDICATOR (JI015).
REFER TO OIL PRESSURE INDICATOR
REMOVALINSTALLATION.

Oil Pressure Indicator
Figure 101 (Sheet 1)

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MODEL 172

MAINTENANCE MANUAL
OIL PRESSURE INDICATOR - MAINTENANCE PRACTICES
1.

Description and Operation
A.

2.

3.

Oil pressure is measured at two points on the engine and gives both indicator readings and low oil
pressure annunciation.
(1) On airplanes with Garmin G1000, the oil pressure is shown on the Multi-Function Display (MFD).
The oil pressure transducer is the same for all avionics packages.
(2) The oil pressure indicator system has an oil pressure line, a transducer and a pressure/
temperature indicator in the cockpit. Oil for the system is tapped at the upper right side of the
case. This oil goes through a rigid line to a transducer on the rear baffle area. This transducer
gives an electrical signal which goes to the oil pressure/oil temperature indicator in the cockpit.
(3) The low oil pressure annunciation system has a pressure switch and related wiring. The switch
is on the upper right rear of the engine case. It is configured so that when oil pressure is below
20 PSI, a ground is supplied to the annunciator in the instrument panel. This causes the OIL
PRESS light on the annunciator to come on. When oil pressure is greater than 20 PSI, the
ground switches to the Hobbs meter and extinguishes the OIL PRESS light.

Oil Pressure Indicator and Transducer Removal/Installation
NOTE:

On airplanes with Garmin G1000, the oil pressure is shown on the Multi-Function Display (MFD).
Refer to Control Display Unit - Maintenance Practices for removal and installation procedures
of the MFD.

NOTE:

Oil pressure transducer removal and installation is typical for all avionics packages.

A.

Remove the Oil Pressure Indicator (Refer to Figure 201).
(1) Make sure the electrical power to airplane is off.
(2) Remove screws that attach the indicator to instrument panel.
(3) Disconnect the electrical connector from forward side of the indicator.
(4) Carefully remove the indicator from the instrument panel.

B.

Install the Oil Pressure Indicator (Refer to Figure 201).
(1) Connect the electrical connector to the indicator.
(2) Put the indicator in position in the instrument panel.
(3) Attach the indicator with the screws.
(4) Operate the engine to make sure the indicator operates correctly.

C.

Remove the Transducer (Refer to Figure 201).
(1) Remove the upper cowl. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Disconnect the oil pressure line at the transducer.
(3) Disconnect the electrical connector from the transducer.
(4) Remove the nut that attaches the transducer to the rear of the baffle and remove the transducer.
(5) Remove the O-ring and fitting, if applicable.

D.

Install the Transducer (Refer to Figure 201).
(1) Install the O-ring and fitting to the transducer.
(2) Install the transducer to the rear baffle and attach with the nut.
(3) Connect the electrical connector to the transducer.
(4) Connect the oil line at the transducer.
(5) Install the upper cowl. Refer to Chapter 71, Cowling - Maintenance Practices.
(6) Operate the engine to make sure the transducer operates correctly and does not have leaks.

Low Oil Pressure Switch Removal/Installation
A.

Remove the Low Oil Pressure Switch (Refer to Figure 201).
(1) Make sure the electrical power to the airplane is off.
(2) Remove the upper cowl. Refer to Chapter 71, Cowling - Maintenance Practices.
(3) Disconnect the electrical connector from the switch.
(4) Remove the switch from the engine case.
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MAINTENANCE MANUAL

B

ELECTRICAL
CONNECTOR
OIL PRESSURE/
TEMPERATURE
INDICATOR

-I/

ELECTRICAL
CONNECTOR

mi

DETAIL A

OIL PRESSURE
SWITCH

C
DETAIL C
OIL PRESSURE
s

'' -'

ESSURE

DUCER

rf
onrn
run

DETAIL B

0510T1007
A0518T1034
B0556T1008
C0556T1006

L

Oil Pressure Indication Installation
Figure 201 (Sheet 1)

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MODEL 172
MAINTENANCE MANUAL
B.

Install the Low Oil Pressure Switch (Refer to Figure 201).

CAUTION: Do not use teflon tape.
CAUTION: Clean any sealer or other foreign object debris from the switch fitting
before Installation. Make sure foreign object debris Is removed and
clear of the pressure hole In the end of the switch fitting.
(1)

Put U544006 sealant (or equivalent) on threads.

CAUTION: Do not use too much torque on the plastic switch connection
housing when the switch Is tightened by hand.
(2)

Install switch and tighten by hand.

CAUTION: Use only the hex fitting to final tighten. Too much torque will damage
the switch. Do not damage the corners of the hex fitting.
(3) Use a 7/16 inch wrench to tighten switch approximately 1 to 1 1/2 turns beyond hand tight. Do
not tighten the switch to more than 60 in-lbs (6.8 N-m).
(4) Connect the electrical connector to the switch.
(5) Install the upper cowl. Refer to Chapter 71, Cowling - Maintenance Practices.

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MODEL 172
MAINTENANCE MANUAL
OIL TEMPERATURE INDICATOR - TROUBLESHOOTING
1.

I

General
A.

On airplanes with Garmin G1000 the oil temperature is shown on the Multi-Function Display (MFD).
Refer to the Garmin G1000 Line Maintenance Manual for GDU 1040 troubleshooting.

B.

This section gives a troubleshooting chart and table to help find the problem that will not let the
oil temperature indicator system function correctly. To help with troubleshooting the oil temperature
indicator, refer to the Model 172 1996 and On Wiring Diagram Manual.
(1) The table that follows is to be used with the troubleshooting chart (refer to Figure 101).

Table 101. Oil Temperature Values
OHMS

Temperature

497 +65 or -65

100°F (38°C)

36 +2 or -2

245°F (118°C)

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MAINTENANCE MANUAL

B1491

THE OIL TEMPERATURE INDICATOR (JI015) DOES NOT OPERATE
OR SHOWS THE INCORRECT TEMPERATURE.

MAKE SURE THERE IS AIRPLANE BUS POWER
AT PIN 1 (PC001) AND PIN 9 (GI001) ON THE WIRE
BUNDLE SIDE OF THE INDICATOR (JI015). IF-

I
OK, MAKE SURE THERE IS A RESISTANCE
OF 34 TO 2000 OHMS BETWEEN PIN 2
(JI015) OF THE INDICATOR CONNECTOR
AND GROUND (SEAT RAIL). IF-

NOT OK, REPAIR OR REPLACE
THE APPLICABLE WIRING.

OK, DISCONNECT THE WIRE FROM THE
SENSOR (UN004). APPLY A VARIABLE
RESISTANCE BETWEEN THE SENSOR
WIRE TERMINAL AND GROUND AS
SHOWN IN TABLE 101. THE INDICATOR
(JI015) MUST SHOW THE TEMPERATURE
GIVEN IN TABLE 101. IF-

NOT OK, DISCONNECT THE
WIRE FROM THE SENSOR
(UN004). MAKE SURE THE
RESISTANCE SHOWS 34 TO
2000 OHMS BETWEEN
THE TEMPERATURE SENSOR
TERMINAL AND GROUND. IFI

NOT OK, REPLACE THE OIL
TEMPERATURE INDICATOR
(JI015). REFER TO OIL
TEMPERATURE INDICATOR
REMOVAL/INSTALLATION.

OK, REPAIR OR
REPLACE THE
APPLICABLE
WIRING BETWEEN
THE SENSOR
(UN004) AND THE
INDICATOR (JI015).

I
NOT OK,
REPLACE
THE SENSOR
(UN004).

Oil Temperature Indicator
Figure 101 (Sheet 1)

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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
OIL TEMPERATURE INDICATOR - MAINTENANCE PRACTICES
1.

Description and Operation
A.
B.

2.

On airplanes with Garmin G1000, the oil temperature is shown on the Multi-Function Display (MFD).
The oil temperature sending unit is the same for all avionics packages.
The oil temperature system has a sending unit, an oil temperature/oil pressure indicator and wire
between the two components. Oil temperature is measured in the accessory case area and gives
cockpit readings in °F.

Oil Temperature Sending Unit RemovaL/Installation
NOTE:

3.

Oil temperature sending unit removal and installation is typical for all avionics packages.

A.

Remove the Oil Temperature Sending Unit (Refer to Figure 201).
(1) Remove the upper engine cowl. Refer to Chapter 71, Cowling - Maintenance Practices.
(2) Disconnect the ring terminal wiring at the sending unit.
(3) Loosen and remove the sending unit from the accessory case.

B.

Install the Oil Temperature Sending Unit (Refer to Figure 201).
(1) Install the sending unit to the accessory case.
(2) Attach the ring terminal wire to the sending unit.
(3) Torque the jamnut to a maximum of 20 in-lbs (2.3 N-m).
(4) Operate the engine to make sure the indicator operates correctly and there are no leaks.
(5) Install the upper engine cowl. Refer to Chapter 71, Cowling - Maintenance Practices.

Oil Temperature/Oil Pressure Indicator Removal/Installation
A. On airplanes with Garmin G1000, the oil temperature is shown on the Mult-Function Display (MFD).
Refer to Control Display Unit - Maintenance Practices for removal and installation procedures of the
MFD.
B.

For removal and installation of the Oil Temperature/Oil Pressure Indicator, refer to Oil Pressure
Indicators - Maintenance Practices.

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MODEL 172

MAINTENANCE MANUAL

B

AA

VIEW A-A

JAMNUTS
SENDING

DETAIL A

0510T1007
AA0550T1007
AS2335C

Oil Temperature Installation
Figure 201 (Sheet 1)

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CHAPTER

STARTING

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL

LIST OF EFFECTIVE PAGES
CHAPTER-SECTION-SUBJECT

PAGE

DATE

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Jul 1/2007

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80-List of Effective Pages
80-Record of Temporary Revisions
80-Table of Contents

80
©Cessna Aircraft Company

-

LIST OF EFFECTIVE PAGES

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Jul 1/2007

RECORD OF TEMPORARY REVISIONS
Temporary Revision
Number

Page Number

Issue Date

By

Date Removed

By

CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

CONTENTS
STARTING - GENERAL..............................
Scope and Definition.............................
STARTER - MAINTENANCE PRACTICES .....................
Description and Operation ..........................
Starter Removal/installation..........................
Bendix Drive Starter Assembly Cleaning And Lubrication ............

©0 Cessna Aircraft Company

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MAINTENANCE MANUAL
STARTING - GENERAL
1.

Scope and Definition
A.

This chapter is comprised of a single section on the starting system. The section details removal and
installation instructions for the engine starter.

©Cessna Aircraft Company

80-00-00 Page 1
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CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
STARTER

-

MAINTENANCE PRACTICES

1.Description and Operation
A.

2.

The airplane is equipped with a direct drive 24 VDC starter mounted at the front (propeller end) lower
left side of the engine. The ignition key in the instrument panel operates the starter solenoid. When
the solenoid is operated, its contacts close and a electrical current energizes the starter. A pinion gear
in the starter engages the crankshaft ring gear. When the engine reaches a given speed, centrifugal
action decouples the starter pinion from the crankshaft ring gear.

Starter RemovaVlnstallation
A.

Remove the Starter (Refer to Figure 201).
(1) Remove the upper and lower engine cowling. Refer to Chapter 71, Engine Cowling Maintenance Practices.
(2) Disconnect the negative terminal from the battery.
(3) Remove the screws securing the left front baffle to the engine assembly.
(4) Remove the baffle from the engine.
(5) Disconnect the large electrical wire which is the positive lead, at the starter.
(6) Cut and discard the safety wire to the bolt securing the alternator attach bracket to the starter.
(7) Remove the bolt that attaches the alternator attach bracket to the starter. If necessary, loosen
the alternator belt.
(8) Remove the one bolt and three nuts that attach the starter to the crankcase and remove the
starter from the engine.

B.

Install the Starter (Refer to Figure 201)
(1) With the one bolt and three nuts, attach the starter to the engine crankcase. Step torque the
fasteners diagonally.

(a) On Sky-Tec starters, torque the bolt and nuts to 204 inch-pounds.

(2) Attach the alternator attach bracket to the starter with the bolt and torque.
~~~~(a)
On Sky-Tec starters, torque the bolt to 204 inch-pounds.
(3) If necessary, reset the alternator belt tension.
(4) Safety wire the bolt to the attach bracket. Refer to Chapter 20, Safetying - Maintenance
Practices.
(5) Connect the positive lead to the starter. Make sure the protective boot fully covers the power
terminal stud on the starter.
(a) On Sky-Tec starters, torque the nut on the power terminal stud to 50 inch-pounds, +5 or -5
inch-pounds.

*

NOTE:

Sky-Tec starters have a metric nut on the power terminal stud.

(6) On Sky-Tec starters, use high-temperature tie straps and connector to attach the positive lead
to the starter. Refer to Figure 202.
(7) Attach the left front baffle to the engine assembly.
(8) Attach the negative terminal to the battery.
(9) Install the upper and lower engine cowling. Refer to Chapter 71, Engine Cowling - Maintenance
Practices.
3.

Bendix Drive Starter Assembly Cleaning And Lubrication
A.

Clean the Bendix starter drive assembly (Refer to Figure 201).

CAUTION: Use only a clean petroleum spirit. Do not use any other type of
solvent.
(1) Clean the starter drive with a clean petroleum spirit.
B.

Lubricate the starter drive assembly (Refer to Figure 201).

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© Cessna Aircraft Company

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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

Bi

LI
A

ALTERNATO
FER

SUMP
VIEw

A-A

0510T 1007
A055OT 1008

Starter Installation
Figure 201 (Sheet 1)

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©D
Cessna Aircraft Company

Page 202
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CESSNA AIRCRAFT COMPANY

MODEL 172

MAINTENANCE MANUAL

DETAIL

A

TARTER
HIGH
TEMPERATURE
TIE STRAP

)NNECTOR
TAN DOFF)

MPERATURE
:STRAP
)SITIVE LEAD)

bULlI

DETAIL

051OTi007
A0550T365
6055OT1 010
C055OT1010

B

Sky-Tec Starter Installation
Figure 202 (Sheet 1)

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©Cessna Aircraft Company

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Jul 1/2007

CESSNA AIRCRAFT COMPANY

MODEL 172
MAINTENANCE MANUAL
CAUTION: Do not use grease, oil or graphite lubricants. Use only silicone spray
lubricants which are recommended for correct operation.
(1) Lubricate the Bendix starter drive assembly with a silicone spray such as Crown Industrial
Products silicone spray 8034.

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©Cessna Aircraft Company

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Jul 1/2007



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