D637 1 13 100 SERIES (1963 THRU 1968) Cessna_100_Series_1962 1968_MM_D637 Cessna 1962 1968 MM

User Manual: Cessna_100_Series_1962-1968_MM_D637-1-13

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SERVICE MANUAL
100 - SERIES
1963 THRU 1968

REVISION 1
4 Aug 2003

D637R1-13

INSERT THE FOLLOWING REVISED
PAGES INTO BASIC MANUAL

Cessna
A Texron Company

SERVICE MANUAL
100 - SERIES
1963 TIHRU 1968
)

MEMBER of GAMA

FAA APPROVAL HAS BEEN OBTAINED ON TECHNICAL DATA IN THIS PUBLICATION
THAT AFFECTS AIRPLANE TYPE DESIGN.
REVISION 1 TO THE BASIC MANUAL IS BEING SUPPLIED TO PROVIDE ADDITIONAL
INFORMATION NECESSARY TO MAINTAIN THE AIRPLANE. REVISION 1
INCORPORATES:
TEMPORARY CHANGE 1, DATED 18 OCTOBER 1977
SERVICE MANUAL CHANGE NOTICE #77-25, DATED 5 DECEMBER 1977
TEMPORARY REVISION 2, DATED 1 JUNE 1993
TEMPORARY REVISION 3, DATED 3 OCTOBER 1994
TEMPORARY REVISION 4, DATED 7 JANUARY 2000 AND
TEMPORARY REVISION 5, DATED 7 OCTOBER 2002.

D637-1-13

SEPTEMBER 1968
REVISION 1

4 Aug 2003

A T.Xtro,

C -np-ny

TEMPORARY REVISION NUMBER 7
DATE July 1, 2007
100 Series (1963-1968) Service Manual

MANUAL TITLE
MANUAL NUMBER

PAPER COPY

MANUAL NUMBER

-AEROFICHE

D637-1 -13
D637-1 -13AF

TEMPORARY REVISION NUMBER
MANUAL DATE

D637-1 TR7

1 September 1968

REVISION NUMBER

DATE

4 August 2003

This Temporary Revision consists of the following pages, which affect and replace existing pages
in the paper copy manual and supersede aerofiche and CD information.
SECTION

2
2
2
5
5
5

PAGE
24

24A
24B
4
4A
4B3

AEROFICHE
FICHE/FRAME

SECTION

PAGE

AEROFICHE
FICHE/FRAME

1B24
ADD
ADD
1D1O
ADD
ADD

REASON FOR TEMPORARY REVISION

1. Incorporate inspection of horizontal stabilizer trim actuators (Section 2).
2. Incorporated inspection of flat spring main landing gear (Section 5).
FILING INSTRUCTIONS FOR THIS TEMPORARY REVISION

1. For Paper Publications, file this cover sheet behind the publication's t'itle page to identify the
inclusion of the Temporary Revision into the manual. Insert the new pages into the publication
at the appropriate locations and remove and discard the superseded pages.
2. For Aerofiche Publications, draw a line with permanent red ink marker, through any aerofiche
frame (page) affected by the Temporary Revision. This will be a visual identifier that the
information on the frame (page) is no longer valid and the Temporary Revision should be
referenced. For "added" pages in a Temporary Revision, draw a vertical line between the
applicable frames. Line should be wide enough to show on the edges of the pages. Temporary
Revisions should be collected and maintained in a notebook or binder near the aerofiche library
for quick reference.
3. For CD publications, mark the temporary revision part number on the CD label with permanent
red marker. This will be a visual identifier that the temporary revision must be referenced when
the content of the CD is being used. Temporary revisions should be collected and maintained in
a notebook or binder near the CD library for quick reference.

AIRCRAFT COMPANY

Cessna

A Textron Company

TEMPORARY REVISION NUMBER 6
DATE 5 April 2004
MANUAL TITLE

Model 100 Series Service Manual (1963 Thru 1968)

MANUAL NUMBER - PAPER COPY

D637-1-13

MANUAL NUMBER - AEROFICHE

D637-1-13AF

TEMPORARY REVISION NUMBER

D637-1TR6

1 September 1968

MANUAL DATE

REVISION NUMBER

DATE

4 August 2003

This Temporary Revision consists of the following pages, which affect and replace existing pages
in the paper copy manual and supersede aerofiche information.
SECTION
2

PAGE
22
24

AEROFICHE
FICHE/FRAME

SECTION

PAGE

AEROFICHE
FICHE/FRAME

1/B21
1/B24

REASON FOR TEMPORARY REVISION
1. To add the cleaning interval of the engine fuel injection nozzles.
FILING INSTRUCTIONS FOR THIS TEMPORARY REVISION
1. For Paper Publications, file this cover sheet behind the publication's title page to identify the
inclusion of the Temporary Revision into the manual. Insert the new pages into the publication
at the appropriate locations and remove and discard the superseded pages.
2.

For Aerofiche Publications, draw a line with permanent red ink marker, through any aerofiche
frame (page) affected by the Temporary Revision. This will be a visual identifier that the
information on the frame (page) is no longer valid and the Temporary Revision should be
referenced. For "added" pages in a Temporary Revision, draw a vertical line between the
applicable frames. Line should be wide enough to show on the edges of the pages. Temporary
Revisions should be collected and maintained in a notebook or binder near the aerofiche library
for quick reference.

LIST OF EFFECTIVE PAGES
INSERT THE LATEST CHANGED PAGES.
DESTROY THE SUPERSEDED PAGES.
Dates of issue for original and Revisions are:
Original................... 0................. September 1,1968
Revision .................. 1....................August 4, 2003
Note:

The portion of the text affected by the revision is indicated
by a vertical line in the outer margins of the page.

*The asterisk indicates pages revised, added, or deleted by current revision.
Page
No.

Revision
No.

TITLE ...............................................
"A" .................................................... 0
i-ii ..................................................... 0

1-1 thru 1-13 .................................... 0
*2-1 thru 2-2B...................................1
2-3 thru 2-10 .................................... 0
2-10A thru 2-10B Blank .................. 0
2-11 thru 2-20 .................................. 0
*2-21 thru 2-27 ................................. 1
3-1 thru 3-14A..................................0
3-14B ...............................................
3-15 thru 3-22A ................................ 0
3-22B Blank ..................................... 0
3-23 thru 3-32 .................................. 0
4-1 thru 4-13 .................................... 0
5-1 thru 5-52 .................................... 0
6-1 thru 6-8A .................................... 0
6-8B Blank ....................................... 0
6-9 thru 6-18 .................................... 0
7-1 thru 7-8A .................................... 0
7-8B Blank ....................................... 0
7-9 thru 7-12A..................................0
7-12B Blank ..................................... 0
7-13 thru 7-17 .................................. 0
8-1 thru 8-12 .................................... 0
*9-1 thru 9-10 ................................... 1
*9-11 Blank (Deleted) ...................... 1
10-1 thru 10-10A..............................0
10-10B Blank ................................... 0
10-11 thru 10-20 .............................. 0
11-1 thru 11-7 .................................. 0
*12-1 thru 12-4.................................1
12-5 thru 12-29 ................................ 0
12-30 Blank......................................0
12-31 thru 12-52 ............................. 0

Page
No.

Revision
No.

12A-1 thru 12A-21 ..................... 0
13-1 thru 13-4B ......................... 0
13-5 thru 13-32B ....................... 0
13-33 thru 13-37 ..................... 0
14-1 thru 14-11 .......................... 0
14A-1 thru 14A-2.......................0
15-1 thru 15-4A ......................... 0
15-4B Blank...............................0
15-5 thru 15-14..........................0
*16-1 thru 16-6B ....................... 1
16-7 thru 16-26A ....................... 0
16-26B Blank.............................0
*16-27 thru 16-36 .................... 1
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18-1 ........................................... 0
18-2 Blank ................................ 0
*19-1 thru 19-6 ......................... 1
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*19-9 thru 19-10 ........................ 1
19-11 thru 19-30 ........................ 0
20-1 thru 20-5 ............................ 0
20-6 Blank ................................. 0
A1-1 ........................................... 0
A1-2 Blank.................................0
(150) 0410011 -15.1 .................0
(172) 0500062 - 16.1 ............... 0
(180 & 185) 0700092 - 16.1 ...... 0
(182) 0770610 - 16.1 ................. 0

TABLE OF CONTENTS

SECTION

Page

GENERAL DESCRIPTION .......................

1-1

GROUND HANDLING, SERVICING, LUBRICATION, AND INSPECTION.

FUSELAGE

.............................

3-1

AIRFRAME

4-1

LANDING GEAR ...........................

AILERON CONTROL SYSTEM ...................

WING FLAP CONTROL SYSTEMS

...................

7-1

ELEVATOR CONTROL SYSTEMS.

...................

8-1

ELEVATOR TRIM TAB CONTROL SYSTEMS

..........................

2-1

5-1
..

.............

RUDDER AND RUDDER TRIM CONTROL SYSTEMS

STABILIZER TRIM CONTROL SYSTEM.

POWERPLANT

12A

6-1

9-1

...........

10-1

................

11-1

...........................

12-1

ENGINE ("BLUE-STREAK" LYCOMING)

.....

12A-1

FUEL SYSTEMS

PROPELLERS ........

14A

PROPELLER (1721)

.........................

14A-1

UTILTYSYBTEMS

.........................

15-1

INSTRUMENTS ANDNSTRUEN

ELECTRICAL SYSTEMS

.......................

17-1

ELECTRONIC SYSTEMS

.......................

18-1

STRUCTURAL REPAIR ........................

PAINTING

APPENDIX A

...........................

13-1
....

14-1

16-1

SYSTEMS ..............

19-1
20-1

.201..........................

WIRING DIAGRAMS ...................

......

Al-l

CROSS REFERENCE LISTING OF POPULAR
NAME VS. MODEL NUMBERS AND SERIALS
All aircraft, regardless of manufacturer, are certificated under model number designations. However,
popular names are often used for marketing purposes. To provide a consistent method of referring to the
various aircraft, model numbers will be used in this publication unless names are required to differentiate
between versions of the same basic model. The following table provides a cross reference listing of popular
name vs. model numbers.
POPULAR NAME
150 STANDARD
150 TRAINER, or
150 COMMUTER

-FRENCH-150

MODEL
YEAR
1963
1964
1965
1966
1967
1968
.1966.
1967
1968

SERIALS
MODEL

BEGINNING

ENDING

150C
150D
150E
150F
150G
150H

15059701
15060088
15060773
15061533
15064533
15067199

15060087
15060772
15061532
15064532
15067198

F150F
F 50G
F150H

F150-0001
F 150-0068
F150-0220

F150-0067
F150-0219

172 or SKYHAWK

1963
1964
1965
1966
1967
1968

172D
172E
172F
172G
172H
1721

17249545
17250573
17251823
17253393
17254893
17256513

17250572
17251822
17253392
17254892
17256512

FRENCH 172

1963
1964
1965
1966
1967
1968

F172D
F172E
F172F
F172G
F172H
F172H

F172-0001
F172-0019
F172-0086
F172-0180
F172-0320
F172-0447

F172-0018
F172-0085
F172-0179
F172-0319
F172-0446

172 POWERMATIC r
SKYHAWK POWERMATIC

1963

P172D

P17257120

P17257188

FRENCH POWERMATIC

1963

FP172D

FP172-0001

FP172-0003

180

1963
1964
1965
1966
1967
1968

180F
180G
180H
180H
180H
180H

18051184
18051313
18051446
18051608
18051775
18051876

18051312
18051445
18051607
18051774
18051875

182 or SKYLANE

1963
1964
1965
1966
1967
1968

182F
182G
182H
182J
182K
182L

18254424
18255059
18255845
18256685
18257626
18258506

18255058
18255844
18256684
18257625
18258505

ARGENTINE 182

1966
1967
1968

A182J
A182K
A182L

A182-0001
A182-0057
A182-0097

A182-0056
A182-0096

185 SKYWAGON
(260 H. P. Engine)

1963
1964
1965
1966

185B
185C
185D
185E

185-0513
185-0654
185-0777
185-0968

185-0653
185-0776
185-0967
185-1149

185 SKYWAGON
(300 H. P. Engine)

1966
1967
1968

A185E
A185E
A185E

185-0968
185-1150
185-1301

185-1149
185-1300

FOREWORD

This manual contains factory recommended procedures and instructions for ground handling, servicing and maintaining Cessna
100-Series aircraft. These include the Models 150, 172, P172, 180,
182, 185, and A185. The Model F172, which is manufactured by
Reims Aviation S.A., Reims (Marne) France, is identical to the 172
except that it is powered by an 0-300-D engine, manufactured under
license by Rolls Royce, Crewe, England. All 172 information in this
manual pertains to the F172 as well. Likewise, the Model FP172 is
identical to the P172 except that it is powered by a GO-300-E Rolls
Royce engine, and the Model F150 is identical to the 150 except that
it is powered by an 0-200-A Rolls Royce engine.
The Model A182, which is manufactured by Directorate National
of Fabrication and Investigation Aeronautical, Cordoba, Argentina, is
identical to the Model 182. All 182 information in this manual pertains
to the A182 as well.
Besides serving as a reference for the experienced mechanic,
this book also covers step-by-step procedures for the less experienced man. This manual should be kept in a handy place for ready
reference. If properly used, it will better enable the mechanic to
maintain Cessna 100-Series aircraft and thereby establish a reputation for reliable service.
The information in this book is based on data available at the
time of publication, and is supplemented and kept current by service
letters and service news letters published by Cessna Aircraft Company. These are sent to all Cessna Dealers so that they have the
latest authoritative recommendations for servicing Cessna airplanes.
Therefore, it is recommended that Cessna owners utilize the knowledge and experience of the factory-trained Dealer Service Organization.
In addition to the information in this Service Manual, a group
of vendor publications are available from the Cessna Service Parts
Center which describe complete disassembly, overhaul, and parts
breakdown of some of the various vendor equipment items. A listing of the available publications is issued periodically in service
letters.

iii

SECTION 1

GENERAL DESCRIPTION

1-1. GENERAL DESCRIPTION. Cessna singleengine aircraft described in this manual are similar
in that all models are high-wing monoplanes, employing patented spring-steel main landing gear
struts, horizontally opposed air-cooled engines,
and all-metal semi-monocoque airframe construction.
1-2. MODEL 150 SERIES. The Model 150 is
equipped with a tricycle landing gear, a four-cylinder
Continental engine, and a fixed-pitch propeller. Twoplace seating is standard, and a two-place child's seat
may be installed as optional equipment. The Model
150D and on features a "wrap around" rear window,
which replaces the rear side windows used on the
Model 150C. Beginning with the Model 150F, a
swept-back fin and rudder is used.
1-3. MODEL 172 SERIES. The Model 172 is
equipped with a tricycle landing gear. Four-place
seating is standard, and a two-place child's seat
may be installed as optional equipment. The Model
172 features rear side windows, a "wrap around"
rear window, and a swept-back fin and rudder.
Prior to 1968, the Model 172 is powered by a sixcylinder Continental engine, and a fixed-pitch propeller. Beginning with 1968, the aircraft is powered
by a four-cylinder "Blue-Streak" (Lycoming) engine,
and a fixed-pitch propeller.
1-4. MODEL P172. The Model P172 is equipped
with a tricycle landing gear, a six-cylinder geared
Continental engine, and a constant-speed propeller.
Four-place seating is standard, and a two-place
child's seat may be installed as optional equipment.
The Model P172 features rear side windows, a
"wrap-around" rear window, and a swept-back fin
and rudder.
1-5. MODEL 180 SERIES. The Model 180 is equipped with a tailwheel-type landing gear, a six-cylinder
Continental engine, and a constant-speed propeller.
On the Model 180F, four-place seating is standard,
and a two-place child's seat may be installed as op-

tional equipment. Beginning with the Model 180G,
the pilot's seat only is standard, while optional seating arrangements include two front seats only, two
front seats with one, two-place rear seat, and two
front seats with two, two-place rear seats of stowable
design. Beginning with 1967, the center stowable
seat is replaced with two individual stowable seats.
The four-place version may be furnished with either
utility or deluxe fabrics, and the rearmost stowable
seat may also be used with the four-place version as
a child's seat.
1-6. MODEL 182 SERIES. The Model 182 is equipped with a tricycle landing gear, a six-cylinder
Continental engine, and a constant-speed propeller.
Four-place seating is standard, and a two-place
child's seat may be installed as optional equipment.
The Model 182 features rear side windows, a "wrap
around" rear window, and a swept-back fin and rudder.
1-7. MODEL 185 SERIES. The Model 185 is equipped with a tailwheel-type landing gear, a fuel-injected
six-cylinder Continental engine, and a constant-speed
propeller. The pilot's seat only is standard, while
optional seating arrangements include two front seats
only, two front seats with one, two-place rear seat,
and two front seats with two, two-place rear seats of
stowable design. Beginning with 1967, the center
stowable seat is replaced with two individual stowable seats. The four-place version may be furnished
with either utility or deluxe fabrics, and the rearmost stowable seat may also be used with the fourplace version as a child's seat.
1-8. Leading particulars of each model, with dimensions based on gross weight, are given in the
following charts. If these dimensions are used for
constructing a hangar or computing clearances, remember that such factors as nose strut inflation,
tire pressures, tire sizes, and load distribution
may result in some dimensions that are considerably
different from those listed.
1-1

MODEL 150
DESIGN GROSS WEIGHT (150C) ..................
DESIGN GROSS WEIGHT (150D & on) ................
FUEL CAPACITY (Total) .....................
Optional . . . . . ..
. . . . . . . . . . . . . . . . ...
OIL CAPACITY .........................
ENGINE MODEL (Refer to Section 12 for Engine Data) ........
PROPELLER (Fixed Pitch).
..........
MAIN WHEEL TIRES (Standard thru 150E) ..........
...
Pressure ........................
MAIN WHEEL TIRES (Standard 150F & on) .............
Pressure .
.........................
MAIN-WHEEL_TIRES (Optional thru 150E)
...........
.
Pressure .............
..............
NOSE WHEEL TIRE (Standard)
.................
Pressure ..........................
NOSE WHEEL TIRE (Optional) . ................
Pressure ..
............
. .....
......
NOSE GEAR STRUT PRESSURE (Strut Extended) ...........
WHEEL ALIGNMENT
Camber . ..
. ...
. ..
. ..
..
. .....
..
...
Toe-In ..........................
AILERON TRAVEL
Up ....
.........................
Down .
...........
............ ...
.
WING FLAP TRAVEL
(Thru 150E) .........................
(150F & on) .......................
RUDDER TRAVEL (Measured perpendicular to hinge line)
Right (Thru 150E) . ..............
..... .16
Left (Thru 150E) .....
.........
.........
Right (150F & on) ...................
.. ..
Left (150F & on) ......................
ELEVATOR TRAVEL
Up .............................
Down ............................
ELEVATOR TRIM TAB TRAVEL
Up .............................
Down ............................
PRINCIPAL DIMENSIONS
Wing Span
(Thru 150E) ...
.......
........
......
(150F & on) .......................
Length
With Large Spinner (Thru 150E) ..............
With Small Spinner (Thru 150E) ..........
....
With Large Spinner (150F & on) .
.............
With Small Spinner (150F & on) ........
.....
Fin Height (Maximum with Nose Gear Depressed)
(Rotating Beacon Installed on Fin, thru 150E) ......
(Rotating Beacon Installed on Fin, 150F) .........
(Flashing Beacon Installed on Fin, 150G & on) .......
Track Width (Thru 150E) ...................
Track Width (150F & on) ...................
BATTERY LOCATION
(150C) ..........
.............
.....
(150D & on) ......
...
....
....
....
....

1500 lb
1600 lb
26 gal
38 gal
6 qt
CONTINENTAL 0-200 Series
69" McCAULEY
5.00 x 5, 4-Ply Rating
30 psi
6.00 x 6, 4-Ply Rating
21 psi
6.00 x 6, 4-Ply Rating
21-psi
. 5.00 x 5, 4-Ply Rating
30 psi
.15
x 6.00 x 6, 4-Ply Rating
35 ps
20 psi
. 4 ° to 6 °
0" to .06"

20 ° , +2°-0°
14°, +2°-0 °
.

0,
10-, 20°, 30,
0 ° to 40 ° ± 2°

40°,

2°

°
°
16 *
°

1°
1°
23 , +0-2
23 ° , +0-2
25 °
15 °

1°
1°

10°
20 °

1°
1°

33'6"
32' 8-1/2"
22'0"
21'7"
23'9"
23'0"
. 7'10"
8'9"
8' 7-1/2"
6'5"
6' 6-1/2"
Aft of Baggage Compartment
Firewall

MODEL 172

2300 lb
DESIGN GROSS WEIGHT .....................
FUEL CAPACITY (Total)
(1963 thru 1968 - Except P172) ................
42 gal.
(P172) . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 gal.
USABLE FUEL
(1963 tbru 1967 - Except P172) ................
39 gal.
(P172) Refer to Owner's Manual. ...............
41-1/2 gal.
(1968 Model 1721) ......................
38 gal.
PROPELLER (Fixed Pitch) ................
.
76" McCAULEY
MAIN WHEELTIRES .......................
6.00 x 6, 4-ply rating
Pressure ..................
....
.
.
24 psi
NOSE WHEEL TIRE (Standard) ..................
5.00 x 5, 4-ply rating
Pressure . ...
...
..
...
. ....
. . . ..
...
. 26 psi
NOSE WHEEL TIRE (Optional)
..
................
6.00 x 6, 4 -ply rating
Pressure ..........
....
.......
.
26 psi

NOSE GEAR STRUT PRESSURE (Strut Extended)

Pressure (Thru 172G) ...................
Pressure (172H & on) ...............
WHEEL ALIGNMENT
Camber . . . . . . . . . . . . . . . . . . . . . . .
Toe-in . . . ..
. . . . . . ..
. . ..
. . . . . . .
AILERON TRAVEL
Up .
...
. . . . . . . . . . . . ..
. ....
. . .
Down............
................
WING FLAP TRAVEL
Manual ..........................
Electric ..........................
RUDDER TRAVEL (Measured perpendicular to Hinge Line)
Right ...................
.........
*Left
............................
ELEVATOR TRAVEL
Up .
..........
. ............
.....
Down. ............................
ELEVATOR TRIM TAB TRAVEL
Up . . . . . . . . . . . . . . . . . . . . . . . . . .
Down ..............
. .............
PRINCIPAL DIMENSIONS
Wing Span ....
....................
Tail Span .........................
Length (Thru 172F) .....................
Length (172G & on) .....................
Fin Height (Maximum with Nose Gear Depressed)
(Rotating Beacon Installed on Fin) .......
....
(Flashing Beacon Installed on Fin) .............
Track Width. .................
.....
BATTERY LOCATION ......................

.45

35 psi
psi

. . . 3 to 5
. . .0" to .06"
°
. . . 20*01
150*10

0, 10° , 20 ° , 30 ° , 40 ° , ± 2
0° to 40 ° ± 2
17°44'±1
17°44'.10
28 ° , +1° -0
23 ° , +1° -0O
. . . 28 ° , +1° -00
13", +10 -0 0
36'2"
. 11'4"
26'6"
26'11"
8'11"
8'9-1/2"
. 7'2"
Firewall

1-3

MODEL P172 (1963)
DESIGN GROSS WEIGHT ...................
FUEL CAPACITY (Total) ....................
...........
OIL CAPACITY ...........
ENGINE MODEL (Refer to Section 12 for Engine Data) .......
PROPELLER (Constant Speed) ..................
MAIN WHEEL TIRES ..................
Pressure .........................
NOSE WHEEL TIRE (Standard) ................
Pressure .........................
.................
NOSE WHEEL TIRE (Optional)
Pressure

Toe-in

...

......................

NOSE GEAR STRUT PRESSURE (Strut Extended).
WHEEL ALIGNMENT
Camber ..........................

2500 lb
52 gal
. 10 qt
CONTINENTAL GO-300 Series
84" McCAULEY
6.00x 6, 4-ply rating
24 psi
5.00 x 5, 4 -ply rating
26 psi
6.00 x 6, 4-ply rating

26 psi

35 psi

.........

3 to 5' to. 06"

..........................

AILERON TRAVEL
20*l1'

Up ...........................

......................
Down .....
WING FLAP TRAVEL ....................
RUDDER TRAVEL (Measured perpendicular to Hinge Line)
.
Right .............
.. . .
. . . . ..
Left. . . . . . . . . . . . .. ..
ELEVATOR TRAVEL
.. ..................
Up.
Don.23-,
..
..
.....
. .....
. ..
....
...
Down ..
ELEVATOR TRIM TAB TRAVEL
. . . . .. . . . . . . . . . . . . .
Up . .
. .
................
Down
PRINCIPAL DIMENSIONS
Wing Span
..
......
.
. .
. .
. ....
..
Tail Span
Length. . . . ....
Fin Height (Maximum with Nose Gear Depressed and
.
Rotating Beacon Installed on Fin) ...........
Track Width . .......................
BATTERY LOCATION ..........................

1-4

15'%l1
i 0, 10', 20', 30', 40', *2
..

17.44'±1'
17-44 1'
26', +1'-o'
+1 -0
23 , +1'-0'

2 ', +1 13', +1'-0-

....

31'. 2"
"
26' 6"

8' 11"
Aft of Baggage Comprtment

0..

MODEL 180
..............
...
DESIGN GROSS WEIGHT (180F)
DESIGN GROSS WEIGHT (180G & on) ................
FUEL CAPACITY (Total) .....................
..........
...........
Optional ...
. ..
...........
OIL CAPACITY .......
ENGINE MODEL (Refer to Section 12 for Engine Data) ........
PROPELLER (Constant Speed) ...............
MAIN WHEEL TIRES (Standard) .................
. .
Pressure . . . . . . . . . . . . . . . . . . ..
MAIN WHEEL TIRES (Optional, Prior to 180G) .........
....
.
..
....
...
. . ...
Pressure . ..
MAIN WHEEL TIRES (Optional) ..................
....
Pressure ...................
TAILWHEEL TIRE (Thru Serial No. 18051262) ..........
..
. ....
. . .......
...
Pressure ...
.....
TAILWHEEL TIRE (Serial No. 18051263 & on) .....
Pressure .........................
WHEEL ALIGNMENT
Camber ...........................
Toe-In ...........................
AILERON TRAVEL
.............
....
Up ........
..............
.............
Down
WING FLAP TRAVEL .....................
RUDDER TRAVEL (Measured perpendicular to hinge line)
Right ...........................
Left
......................
ELEVATOR TRAVEL (With stabilizer full down)
Up ............................
Down . . . . . . . . . . . . . . . . . . . . . . . .
STABILIZER TRAVEL
....
Up ........................
...........
Down ..........
PRINCIPAL DIMENSIONS
Wing Span ..........................
........
Tail Span ..................
Length
......
............
(Thru 1966).
(1967 and on) ......................
Fin Height
(Rotating Beacon Installed on Fin) .............
(Flashing Beacon Installed on Fin) ............
Track Width ...............
.......
BATTERY LOCATION ......................

2150 lb
26001lb
6.5 gal
.
84 gal
..
12 qt
CONTINENTAL 0-470 Series
. 82" McCAULEY
6.00 x 6, 6-Ply rating
.....
30 psi
. .00 x 6, 4-Ply rating
..
. .23 psi
8.00 x 6, 6-Ply rating
..
.23 psi
.8.00 S.C., 6-Ply rating
..
. .35 psi
8.00 x 2. 80, 4-Ply rating
.*55 psi to 65 psi maximum
4° to 6°
0 to . 12"
20 ° ± 2 °
14° ± 2 °
0 ° , 10 ° , 20 ° , 32 ° , 38 ° , +2 ° -1°
24 ° , +0 ° -1 °
24 °, +0 ° -1°
25 ° + 1 °
23 ° ± 1

. .

45' ± 15
8°45 ' ± 15'
36'2"
0'10"
. 25'6"
25'9"
.7'10-1/2"
7'9"
. 7'8"
ft of Baggage Compartment

*55 psi to 65 psi maximum (2300 lb to 2800 lb normal operating loads).

1-5

MODEL 182
DESIGN GROSS WEIGHT ....................
FUEL CAPACITY (Total) .....................
Optional ..............
............
.
. .........
...
OIL CAPACITY .........
ENGINE MODEL (Refer to Section 12 for Engine Data) ........
PROPELLER (Constant Speed) ..................
MAIN WHEEL TIRES (Standard) .................
Pressure ...........................
MAIN WHEEL TIRES (Optional) .................
Pressure ...........................
NOSE WHEEL TIRE (Standard). .................
Pressure (Thru 182J) ...................
Pressure-(182K & on)......
........
....
NOSE WHEEL TIRE (Optional) ...................
Pressure (Thru 182J) ...................
Pressure (182K & on) .....................
NOSE GEAR STRUT PRESSURE (Strut Extended)
(Thru 182J) .........................
......
(182K & on) .................
WHEEL ALIGNMENT
..
.......
Camber ................
Toe-In . . . . . . . ..
.. . . . . . . . . . . . . . .
AILERON TRAVEL
Up ..
..............
...
...............
Down ...........
WING FLAP TRAVEL (Electrically Operated) ............
RUDDER TRAVEL (Measured perpendicular to hinge line)
Right ............................
Left . . ..
. . ..

. . ..

. ....

2800 lb
65 gal
84 gal
12 qt
CONTINENTAL 0-470 Series
82" McCAULEY
6.00 x 6, 6-Ply rating
32 psi
.. 8.00 x 6, 6-Ply rating
25 psi to 35 psi
5.00 x 5, 6-Play rating
.. 32 psi
. . 50 psi
.
00-x
6 6,-4-P-lyrating
20 psi to 29 psi
30 psi
50 psi
55 psi to 60 psi
to 7 °

. .0" to .06"
20 ° + 2°
15 ° * 2°
0 ° to 40 ° , +1 ° -2 °
27013 ' * 1
27°13 ' * 1°

. .....

ELEVATOR TRAVEL
Up . ...........................

26 ° * 1

Down ............................
ELEVATOR TRIM TAB TRAVEL
Up .
...........................

1°

25 °

2°

15° * 1°

Down ............................
PRINCIPAL DIMENSIONS

36'2"

Wing Span ..........................
Tail Span
(Thru 182G)
(182H & on)

10'10"
11'8"

.......................
.......................

Length
27'4"

(Thru 182G) .......................

(182H thru 182J) ...................
(182K & on) .................
Fin Height (Maximum with Nose Gear Depressed)
(Rotating Beacon Installed on Fin) .............
(Flashing Beacon Installed on Fin) .............
Track Width .........................
BATTERY LOCATION ......................

1-6

..
.....

27'10"
28'-1/2"
9'0"
8'10-1/2"
7'11-1/2"
Aft of Baggage Compartment

MODELS 185 & A185
DESIGN GROSS WEIGHT
(Thru 1965 Model 185D) ..............
(1966 and 1967 Models 185E & A185E). .............
(1968 Model A185E) ......................
FUEL CAPACITY (Total) .....................
Optional ..........................
OIL CAPACITY ..............
.......
ENGINE MODEL (Refer to Section 12 for Engine Data)
260 HP (Thru 185E) ......................
300 HP (A185E and on) ..................
PROPELLER (Constant Speed)
260 HP (Thru 185E) ......................
300 HP (A85E and on) ....................
MAIN WHEEL TIRES (Standard) ....
.............
Pressure ......................
MAIN WHEEL TIRES (Optional)

..............

3200 lb
3300 lb
3350 lb
65 gal
. 84 gal
. 12 qt
CONTINENTAL IO-470 Series
. CONTINENTAL IO-520 Series
88" McCAULEY
82" McCAULEY
6.00 x 6, 6-Ply rating
35 psi
8.00 x 6, 6 -Ply rating

..................

Pressure .................
TAILWHEEL TIRE (185B) . .
Pressure ..................
TAILWHEEL TIRE (185C and on)
Pressure .........................
WHEEL ALIGNMENT
Camber ........................
Toe-In ...........................
AILERON TRAVEL

....
..............

25 psi
10.00 x 3.50, 4-Ply rating
45 psi
8.00 x 2. 80, 4-Ply rating
*55 psi to 70 psi (max)

...

................

Up ......
...............
Down .......................
WING FLAP TRAVEL ......................

4° to 6 °
0" to. 12"
+2°
14 ° + 2°
0, 10, 20 ° , 32 ° , 38 ° , +2 ° -1 °

.20°
....

RUDDER TRAVEL (Measured perpendicular to hinge line)

24 ° , +0
24 ° , +0

Right
..........................
Left .

ELEVATOR TRAVEL (With stabilizer full down)
Up .........
Down . ....

..................
. . .....

.
....

. . ..

...

STABILIZER TRAVEL
Up

1°
1°

.0°45 ' + 15'
. .. 0°45', +45'-15'

(Thru 185E) ......................
(A185E and on)
................

Down ............................
PRINCIPAL DIMENSIONS
Wing Span
.......
............
Tail Span ...................
Length
(Thru 1966) .....................
(1967 and on) ......................
Fin Height
(Rotating Beacon Installed on Fin) .............
(Flashing Beacon Installed on Fin) .............
Track Width .......................
BATTERY LOCATION ....................

25 °
23 °

-1 °
-1 °

8°30' 15'
.......

.36'2"
0'10"
25'6"
25'9"
7'10-1/2"
7'9"
7'8"
Aft of Baggage Compartment

*55 psi to 70 psi maximum (2300 lb to 3200 lb normal operating loads). If the 10-inch tire has been replaced
with the 8-inch tire, these pressures also apply to the Model 185B.
1-7

22.12
192.0

31. 75
44.12

56.8769

0.00
1.3

OD 5
150E
THRUMODE

173.41

49.69
11.00
56.69
18.3536.00.Rer-en
0.00
Fig
-

11.00

\/r76.44
" \
38.00 49.69/ 71.44

[_-----------------------I
11.00 36.00

Figure 1-1.
1-8

95.00

133.31

200.37

173.41

49.69

Reference Stations - Model 150 (Sheet 1 of 2)

200.37

200. 37

MODEL150
AND.150E

18.50

56.69
70.69

0.00

200 37

8.37

36.00

76.44

150F & ON

49.69 71.44

SHOP NOTES:

Figure 1-1.

Reference Stations - Model 150 (Sheet 2 of 2)
1-9

1-10

23.62

124.00

65.33

0.00 17.00

156.00

185.50

209.00

92.00
8.12

45.00
56. 70

79.00

MODEL 182H & ON

Figure 1-3.

Reference Stations - Model 182

1-11

23.62
39.00

REAR SIDE WINDOW NOT INSTALLED ON MODEL 180F

8.12

44.00

90.00

Figure 1-4. Reference Stations - Models 180 and 185
1-12

TORQUE VALUES IN POUND-INCHES

BOLT SIZE
(See Note 1)

FINE THREAD SERIES
SHEAR TYPE NUTS
STANDARD TYPE NUTS
Alternate
Alternate
Values
MS20364, AN320
Values
(See Note 2)
AN320
AN316, AN7502
AN310
(See Note 4)
(See Note 4)

10-32
1/4-28
5/16-24
3/8-24
7/16-20
1/2-20
9/16-18
5/8-18
3/4-16
7/8-14
1-14
1-1/8-12
1-1/4-12

20-25
50-70
100-140
160-190
450-500
480-690
800-1000
1100-1300
2300-2500
2500-3000
3700-5500
5000-7000
9000-11000

20-28
50-75
100-150
160-260
450-560
480-730
800-1070
1100-1600
2300-3350
2500-4650
3700-6650
5000-10000
9000-16700

12-19
30-48
60-106
95-170
270-390
290-500
480-750
660-1060
1300-2200
1500-2900
2200-4400
3000-6300
5400-10000

12-15
30-40
60-85
95-110
270-300
290-410
480-600
660-780
1300-1500
1500-1800
2200-3300
3000-4200
5400-6600

COARSE THREAD SERIES
BOLT SIZE
(See Note 1)
8-32
10-24
1/4-20
5/16-18
3/8-16
7/16-14
1/2-13
9/16-12
5/8-11
3/4-10
7/8-9
1-8
1-1/8-8
1-1/4-8

STANDARD TYPE NUTS
(See Note 3)
12-15
20-25
40-50
80-90
160-185
235-255
400-480
500-700
700-900
1150-1600
2200-3000
3700-5000
5500-6500
6500-8000

SHEAR TYPE NUTS
MS20364, AN320, AN316
7-9
12-15
25-30
48-55
95-100
140-155
240-290
300-420
420-540
700-950
1300-1800
2200-3000
3300-4000
4000-5000

NOTES:
(1) AN3, AN23, AN42, AN173, MS20004, NAS334, NAS464 Series Bolts;
AN502, AN503, NAS220 and NAS517 Series Screws.
(2) AN310, AN315, AN345, AN362, AN363, MS20365, AN366, NAS679, "EB,"
"1452," "Z1200, " "UWN" and other self-locking nuts.
(3) AN310, AN340, MS20365, AN366 and other self-locking anchor nuts.
(4) When using AN310 and AN320 castellated nuts where alignment between
bolt and cotter pin holes is not reached using normal torque values, use
alternate torque values or replace nut.

These torque values are derived from oil-free cadmium-plated threads, and are recommended for all
installation procedures contained in this book except where other values are stipulated. They are not
to be used for checking tightness of installed parts during service.

1-13

SECTION 2
GROUND HANDLING, SERVICING, LUBRICATION, AND INSPECTION
TABLE OF CONTENTS
GROUND HANDLING ...........................................
Towing ..............................................................
Hoisting.............................................................
Jacking .............................................................
Parking .............................................................
Tie-Down ..........................................................
Hangar Storage................................................
Outside Storage ...............................................
Extended Storage.............................................
Returning Airplane to Service ..........................
Leveling ............................................................
SERVIC ING ...........................................................
Fuel...................................................................
Fuel Drains.......................................................
Engine Oil.........................................................
Engine Induction Air Filters ..............................
Vacuum System Filters ....................................
Battery ..............................................................
Tires..................................................................
Nose Gear Shock Strut ....................................
Nose Gear Shimmy Dampener (Models 150
and 172) ...........................................................
Nose Gear Shimmy Dampener (Model 182
Prior to 1967)....................................................
Shimmy Dampener (1967 Model 182 and
On)..................................................................
Hydraulic Brake System s...............................
Castering Axle................................................
Oxygen Cylinder.............................................
Face Masks....................................................
CLEANING ..........................................................
W indshields and Windows .............................
Plastic Trim .....................................................
Aluminum Surfaces........................................
Painted Surfaces............................................
Engine Com partment .....................................
Upholstery and Interior...................................
Propellers .......................................................
W heels............................................................

Page
2-2
2-2
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-5
2-5
2-5
2-5
2-5
2-5
2-7
2-8
2-8
2-8
2-8
2-9
2-9
2-9
2-10
2-10
2-10
2-10
2-10
2-10
2-10
2-10
2-10
2-1 0A
2-10A
2-10A
2-10A

LUBRICATION..................................................
Nose Gear Torque Links..............................
Rudder Trim Wheel Threads (Model 185
Series)..........................................................
Tachometer Drive Shaft ...............................
Wheel Bearing Lubrication ...........................
Castering Axle..............................................
INSPECTION....................................................
Airplane File ........................................
Engine Runup ........................................
Scope and Preparation (Continental
Engine).........................................................
Scope and Preparation ("Blue Streak
Lycoming")
........................................
Propeller.......................................................
Engine Compartment ...................................
Fuel System ........................................
Landing Gear ........................................
Airframe........................................................
Control Systems...........................................
COMPONENT TIME LIMITS.............................
General........................................................
Cessna-Established Replacement Time
Limits ............................................................
Supplier-Established Replacement Time
Lim its ............................................................

Revision 1
© Cessna Aircraft Company

Page
2-10A
2-10A
2-1 0A
2-10A
2-10A
2-10A
2-10A
2-19
2-19
2-19
2-20
2-20
2-20
2-20
2-22
2-22
2-23
2-23
2-25
2-25
2-25
2-26

2-1
Aug 4/2003

2-1.

GROUND HANDLING.

2-2.

TOWING.
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. When no tow bar is available, press down at the horizontal stabilizer front spar, adjacent to
the fuselage, to raise the nose wheel off the ground. With the nose wheel clear of the ground, the
airplane can be turned by pivoting it about the main wheels.
CAUTION: WHEN TOWING THE AIRPLANE, NEVER TURN THE NOSE WHEEL MORE THAN 30
DEGREES EITHER SIDE OF CENTER OR THE NOSE GEAR WILL BE DAMAGED.
DO NOT PUSH ON CONTROL SURFACES OR OUTBOARD EMPENNAGE
SURFACES. WHEN PUSHING ON THE TAILCONE, ALWAYS APPLY PRESSURE AT
A BULKHEAD TO AVOID BUCKLING THE SKIN.

B1838

USE TOW BAR CAREFULLY TO AVOID
SCARRING FNISH ON SPEED FAIRING
Figure 2-1. Typical Tow Bars

2-2
© Cessna Aircraft Company

Revision 1
Aug 4/2003

B1840

MASONITE BLOCK 4" SQUARE AND 1" THICK
WITH DEPRESSION FOR JACK IN UNDERSIDE. PAD TOP SIDE WITH 1/4" RUBBER.

ADJUSTABLE
STAND
ATTACHED TO TIE-DOWN RING

(PART NO. 10004-98)
AVAILABLE FROM THE
CESSNA SERVICE PARTS
CENTER

1. Wing jacks must be short enough to slide under front spar of wing just outboard of wing strut,
must extend far enough to raise wheels off ground, and must be of adequate strength.
2. Jacks short enough to slide under Model 150 wings, with leg extensions or adapter stands for
other models with higher wings, are recommended.
3. Be sure the tail stand weighs enough to keep the tail down under all conditions and that it is
strong enough to support any weight that may be placed on it.
4. Jacking one wing is not recommended due to landing gear flexibility. However, if adequate
precautions against slipping are taken, it is permissible.
5. Lowering the tail on tricycle gear aircraft and pushing up at the front spar of the wing will
gain additional height for initially positioning jacks.
6.

Operate jacks evenly until desired height is reached.

The universal jack point may be used to jack one wheel. Do not use the brake casting as a
jack point. Flex brake line away from gear spring when using the universal jack point.

8. The nose may be raised by weighting down the tail. Place weight on each side of stabilizer,
next to fuselage.
9. On conventional gear aircraft, place a suitable stand under the tailwheel to raise the tail until
the aircraft is approximately level before jacking the wings.
Figure 2-2. Jacking Details

Revision 1
©Cessna Aircraft Company

2-2A/2-2B
Aug 4/2003

2-3. HOISTING.

The airplane may be lifted with a

a. Rotate the propeller by hand at least four rev-

hoist of two-ton capacity by using hoisting rings,

olutions every few days to maintain an oil film on

which are optional equipment on all airplanes ex-

the internal parts of the engine.

cept the Model 150, or by means of suitable slings.

The front sling should be hooked to each upper engine
mount at the firewall, 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.
2-4. JACKING.
cedures.

Refer to figure 2-2 for jacking proCAUTION

When using the universal jack point, flexibility
of the gear strut will cause the main wheel to
slide inboard as the wheel is raised, tilting
the jack. The jack must then be lowered for
a second jacking operation. Jacking both
wheels simultaneously with universal jack
points is not recommended.
2-5. PARKING. Parking precautions depend principally on local conditions. As a general precaution,
it is wise to set the parking brake or chock the
wheels, and install the control lock. In severe
weather and high wind conditions, tie down the airplane as outlined in paragraph 2-6 if a hangar is
not available.
2-6. TIE-DOWN should be accomplished in anticipation of high winds. Tie down airplane as follows:
a. Tie ropes or chains to the wing tie-down fittings
located at the upper end of each wing strut. Secure
the opposite ends of the ropes or chains to ground
anchors.
b. Secure a tie-down line through the nose gear tiedown ring. On tricycle gear aircraft without a nose
gear tie-down ring, use a rope (no chains or cables)
to secure the upper strut (exposed portion of engine
mount on the Model 150) to ground anchors.
c. On tricycle gear aircraft, secure the middle of
a length of rope to tail tie-down ring. Pull each end
of rope away at a 45° angle and secure to ground
anchors at each side of tail. On aircraft with conventional tailgear, tie down the tailwheel. Some
Model 180 and 185 aircraft are equipped with a tiedown ring at the tailgear.
d. Install surface control locks between wing tip
and aileron, and over fin and rudder.
e. Install control lock on pilot's control column if
available; if control lock is not available, tie pilot's
control wheel back with front seat belt.
2-7. HANGAR STORAGE. An aircraft stored in a
hangar will require little attention. The following
operations will maintain it in a serviceable condition.
NOTE
If the aircraft is to be stored for a period of
more than 30 days, see paragraph 2-9.

Ignition switch must be OFF when rotating
propeller by hand.
b.
tion
c.
lyte

Keep fuel tanks full to retard moisture condensain the tanks.
Keep battery fully charged to prevent the electrofrom freezing in an unheated hangar.

2-8. OUTSIDE STORAGE. Short-term storage of an
aircraft requires secure tie-down procedures in
accordance with paragraph 2-6, as well as the precautions listed in paragraph 2-7. In addition, the
pitot tube, air vents, openings in the engine cowling,
and other similar openings should have protective
covers installed if rain, sleet, snow, or blowing dust
are anticipated.
EXTENDED STORAGE. Although the aircraft
2-9.
is constructed of corrosion resistant Alclad aluminum which will last indefinitely under normal conditions if kept clean, these alloys are subject to
oxidation. The first indication of corrosion on unpainted surfaces is the form of white deposits or
spots. On painted surfaces, the paint is discolored
or blistered. Storage in a dry hangar is essential to
good preservation and should be procured if possible.
varying conditions will alter the measures of preservation, but under normal conditions in a dry hangar
and for storage periods not to exceed three months,
the following methods of treatment are suggested:
a. Fill fuel tanks with gasoline.
b. Clean and wax aircraft thoroughly.
c. Clean any oil or grease from tires and coat
tires with a tire preservative. Cover tires to protect against grease and oil.
d. Block up fuselage to remove weight from tires.
NOTE
Tires will take a set, causing them to become
out-of-round, if an aircraft is left parked for
more than a few days. For this reason, a
stored aircraft should not have its weight on
the tires.
e. Lubricate all airframe items and seal or cover
all openings.
f. Remove battery and store in a cool dry place;
service battery periodically and charge as required.
g. Inspect for corrosion at least once a month and
remove dust collections as frequently as possible.
Clean and wax as required.
If the engine has been in temporary storage and will
be stored and not operated for a period of from 30
to 60 days, the engine should be treated for extended
storage. The engine is treated for storage prior to
airframe treatment.
a.

Operate engine until oil temperature reaches
2-3

normal operating range. Drain engine oil sump
completely, and install sump drain plug.
b. (LYCOMING ENGINE). Fill oil sump to normal
capacity with corrosion-preventive mixture meeting
specification MIL-C-6529C (Esso "Rust Bane 628" or
equivalent) which has been preheated to 220°F
(104°C).
(CONTINENTAL ENGINE). Fill oil sump to
normal capacity with corrosion-preventive oil
(Continental Motors Corporation recommends
Cosmoline No. 1223, supplied by E. F. Houghton &
Co., 305 W. Lehigh Ave., Philadelphia, Pa.), which
has been pre-heated to 225°F (107. 2°C).
c. Start and operate engine at 1200-1500 rpm for
four to five minutes.

e. Remove, clean, and install oil filter screens.
Install new filter element on aircraft equipped with
external filter.
NOTE
Preheat the preservative mixture to 200-220°F
(93-104°C) for all spraying operations described
in the following.
f. Disconnect ignition harness and remove all spark
plugs. Spray each cylinder through the spark plug
holes with two ounces of preservative mxiture while
the engine is turned five full revolutions for each cylinder. Store spark plugs.
g. Remove and store the exhaust pipes and spray
the exhaust port and exhaust valve of each cylinder
with piston 1/4 turn before top dead center on the
-cylinder-exhaust-stroke
h. Spray each cylinder through spark plug holes
without engine rotation. Install spark plugs or solid
plugs in lower spark plug holes; install cylinder
dehydrator plugs in upper spark plug holes, and install metal covers over cylinder exhaust ports.
i. Cover spark plug cable terminals with tape, and
cover all other engine and accessory vents, and other
openings with a vapor-proof covering material.
j. Attach a warning placard on the throttle control
to the effect that the engine contains no lubricating
oil. Placard the propeller to the effect that it should

CAUTIONi
Do not exceed maximum allowable engine
temperatures.
d. Stop engine and drain preservative mixture from
oil sump. The preservative mixture may be saved
and re-used.
NOTE
The corrosive-preventive mixture is harmful
to paint and should be wiped from painted
surfaces immediately.

-i

. ,

:.^^^

CONTROL
WIH
SURFACE
LOCKS

TAIL

ELASTIC

WHEEL

STRAP

TieFigure 2-3.

DOWN

.
-

Figure 2-3.
2-4

WIN

Tie-Down

WITH CONTROL LOCK
OR SAFET

not be rotated while the engine is in storage.
k. Perform steps "a" thru "g" after the engine is

prepared for storage.
1. The preceding is applicable only for storage
periods not exceeding 60 days. Should it become
necessary to extend the storage period beyond the
60 day limit, the storage procedure shall be repeated.
2-10. RETURNING AIRCRAFT TO SERVICE. After
short-term storage, returning the aircraft to service
is accomplished by completing a thorough pre-flight
inspection. After an extended storage, use the following procedure to return the aircraft to service.
a. Remove aircraft from blocks and check tires
for proper inflation. Check for proper nose gear
strut inflation.
b. Check and install battery.
c. Remove all materials used to seal and cover
openings.
d. Remove warning placards posted at throttle
control and on propeller.
e. Remove and clean engine oil screens, then install and safety screens. If an external filter is
installed, install new element,
f. Drain engine oil sump. Install and safety drain
plug, then service engine with correct grade and
quantity of engine oil.
NOTE
The corrosive-preventive mixture will mix
with engine lubricating oil, so flushing the
oil system is not necessary. Draining the
oil sump will remove enough of the corrosivepreventive mixture. However, after 25 hours
of operation the engine oil should be drained
while the engine is hot. This will remove any
residual corrosive-preventive mixture that
may be present in the oil system.
g. Remove dehydrator plugs installed in upper
spark plug holes, and remove spark plug or solid
plugs installed in lower spark plug holes. Rotate
propeller several revolutions to clear corrosionpreventive mxiture from the cylinders and to saturate
the interior of the engine with clean lubricating oil.
NOTE
The corrosion-preventive mixture is harmful
to paint and should be wiped from painted
surfaces immediately.
h. Remove cover plates and install exhaust pipes.
i. Clean, gap, and install spark plugs and connect
spark plug leads.
j. Check fuel strainer and drain carburetor. Remove and clean fuel strainer filter screen if necessary. Check fuel tanks and fuel lines for moisture
condensation and sediment and drain enough fuel to
eliminate any moisture.
k. Service induction air filter,
1. Perform a thorough pre-flight inspection, then
start and warm-up engine.

2-11. LEVELING. Corresponding points on both
upper door sills may be used to level all models

laterally. References for longitudinal leveling are:
Model 150C (1963) - Top edge of fuselage splice
plate.
Models 150D & on, 172, P172, and 182 - Top
of tailcone between rear window and vertical
fin.
Models 180 and 185 - Lower surface of upper
door sill
2-12.

SERVICING.

2-13. Servicing requirements are shown in the Servicing Chart (figure 2-4). The following paragraphs
supplement this figure by adding details not included
in the chart.
2-14. FUEL. Fuel tanks should be filled immediately after flight to lessen moisture condensation. Tank
capacities are listed in Section 1. The recommended
fuel is 80/87 minimum, aviation grade gasoline, for
all except the Model 185 and A185 Series airplanes,
which require 100/130 aviation grade gasoline.
2-15. FUEL DRAINS are located at various points in
the fuel systems to provide for drainage of water and
sediment. Each aircraft is equiped with a fuel
strainer drain valve, fuel line or selector valve drain
plugs or drain valves, and fuel tank sump drain plugs
or drain valves. In many airplanes, the fuel strainer
drain valve may be operated by a control located at
the instrument panel. During the 1967 model year
the strainer drain control was removed from the
instrument panel and relocated adjacent to the engine
oil dipstick. Access to the strainer drain control is
through the engine oil dipstick access door. Remove
drain plugs and open strainer drain at the intervals
specified in figure 2-4 to drain water and sediment
from the fuel system. Also, during daily inspection
of the fuel strainer, if any water is found in the fuel
strainer, there is a possibility that wing tank sumps,
lines, and accumulator tank contain water. Therefore, all fuel drain plugs should be removed and
all water drained from the fuel system.
2-16. ENGINE OIL. Check engine lubricating oil
with the oil dipstick five to ten minutes after the
engine has been stopped. The aircraft should be in
as near a level position as possible when checking
engine oil, so that a true reading is obtained. Engine
oil should be drained while the engine is still hot and
the nose of the aircraft should be raised slightly for
more positive draining of any sludge which may have
collected in the engine oil sump.
Engine oil should be changed every four months even
though less than the specified hours have accumulated.
Reduce these intervals for prolonged operation in
dusty areas, in cold climates where sludging conditions
exist, or where short flights and long idle periods
are encountered, which cause sludging conditions.
Always change oil, clean oil screens, and/or change
external filter element whenever oil on the dipstick
appears dirty.

2-5

craft equipped with an external oil filter, the engine
oil change intervals may be extended to 100-hour
intervals providing the external filter element is
changed AT 50-HOUR INTERVALS.

Detergent or ashless dispersant oil conforming to
Lycoming Specification No. 301E for the "Blue
Streak" (Lycoming) engine or conforming to Continental Motors Specification MHS-24A for the Continental engine shall be used in these engines. Multiviscosity oil may be used to extend the operating
temperature range, improve cold engine starting and
lubrication of the engine during the critical warm-up
period, thus permitting flight through wider ranges of
climate change without the necessity of changing oil.
The multi-viscosity grades are recommended for aircraft engines subjected to wide variations in ambient
air temperatures when cold starting of the engine
must be accomplished at temperatures below 30 ° F.

CONTINENTAL ENGINE. On aircraft equipped with
an external oil filter, change engine oil and filter
element at 50-hour intervals. On aircraft NOT
equipped with an external oil filter, change engine
oil and clean the oil screen EVERY 25 HOURS.
NOTE
Detergent or ashless dispersant oil conforming
to Continental Motors Specification MHS-24A
MUST be used in all Model A185 series aircraft and in the 1966 and 1967 Model 172 series
aircraft. However straight-mineral-oil-maybe used in all other models equipped with Continental engines, detergent or ashless dispersant oil conforming to Continental Motors
Specification MHS-24A is recommended. On
models where a straight mineral oil has been
used continuously, converting to detergent or
ashless dispersant oil is not recommended
except at engine overhaul or replacement.

NOTE
New or newly overhauled engines should be
operated on aviation grade straight mineral
oil until the first oil change, or until oil consumption has stabilized. If a detergent or
ashless dispersant oil is used in a new engine,
or a newly overhauled engine, high oil consumption might possibly be experienced. The
anti-friction additives of some detergent and
ashless dispersant oil will retard the "breakin" of the piston rings and cylinder walls.
This condition can be avoided by the use of
straight mineral oil until normal oil consumption is obtained, then change to detergent
or ashless dispersant oil. The aircraft is
delivered from Cessna with straight mineral
oil of the correct viscosity.

Oil capacities for the different models are given in
the following chart. To minimize loss of oil through
the breather, fill to specified oil level on dipstick for
normal operation (flight of less than three hours).
For extended flight, fill to full mark on dipstick. Do
not operate with less than minimum-for-flight quantities listed. If an external oil filter is installed, one
additional quart of oil is required when filter element
is changed.

"BLUE STREAK" (Lycoming) ENGINE. On aircraft
NOT equipped with an external oil filter, change oil
and clean oil screens at 50-hour intervals. On air-

ALL ENGINES

MODEL

CAPACITY
(TOTAL)

NORMAL
OPERATION

MINIMUM
FOR FLIGHT

150

172

P172

180

182

185

SHOP NOTES:

2-6

CAPACITY (TOTAL
WITH FILTER)

When adding or changing oil, use aviation grade oil
in accordance with the following chart.
CONTINENTAL ENGINES
ABOVE 40 ° F

BELOW 40 ° F

MODEL

GRADE

MODEL

150
172 (Prior to 172G)
P172
172G and on
180
182
185
A185

SAE
SAE
SAE
SAE
SAE
SAE
SAE
SAE

150
172 (Prior to 172G)
P172
172G and on
180
182
185
A185

40
40
40
50
50
50
50
50

*GRADE
SAE
SAE
SAE
SAE
SAE
SAE
SAE
SAE

10W30
10W30
10W30
10W30
10W30
10W30
10W30
10W30

or
or
or
or
or
or
or
or

SAE
SAE
SAE
SAE
SAE
SAE
SAE
SAE

20
20
20
30
30
30
30
30

*Multi-viscosity oil with a range of SAE 10W30 is recommended for improved cold weather starting.
However, since this oil is also a detergent oil, it should not be used in those models where a straight
mineral oil is being used, except as noted in the preceding text.

"BLUE STREAK" (Lycoming) ENGINE

MODEL

GRADE
SAE
SAE
SAE
*SAE

1721 and on

50
30
20
10W30

AMBIENT TEMPERATURE
ABOVE 60°F
0° to 70°F
BELOW 10°F

*Multi-viscosity oil with a range of SAE 10W30 is recommended for improved cold weather starting
and lubrication of the engine during the critical warm-up period. Detergent or ashless dispersant
oil, conforming to Lycoming Specification No. 301E MUST BE USED.

2-17. ENGINE INDUCTION AIR FILTER. The induction air filter keeps dust and dirt from entering the
induction system. The value of maintaining the air
filter in a good clean condition can never be overstressed. More engine wear is caused through the
use of a dirty or damaged air filter than is generally
believed. The frequency with which the filter should
be removed, inspected, and cleaned will be determined primarily by aircraft operating conditions. A
good general rule however, is to remove, inspect,
and clean the filter at least every 50 hours of engine
operating time and more frequently if warranted by
operating conditions. Some operators prefer to hold
spare induction air filters at their home base of
operation so that a clean filter is always readily
available for use. Under extremely dusty conditions,
daily servicing of the filter is recommended. Two
types of filters are used. One is a flock-coated,
oiled filter and the other is a dry, paper-media
filter.
NOTE
The Model 172-series prior to 1968, and all
Model 150 aircraft are equipped with a flockcoated, oiled filter when it leaves the factory.

However, when spares stocks are exhausted.
new filters ordered from Cessna Service Parts
Center will be the dry type with an improved
element. The 1968 Model 1721 is equipped
with the dry type filter.
To service the flock-coated, oiled filter, proceed as
follows:
a. Remove filter from aircraft.
b. Wash filter thoroughly, soiled face down in
solvent (Federal Specification P-S-661 or equivalent).
c. Drain and dry filter, then dip flock-coated
screen filter in the same grade of oil used in the
engine and allow excess oil to drain off.
d. Be sure air box is clean, inspect filter and replace if damaged.
NOTE
A damaged filter may have broken filtering
panels or the flock coating may be missing
from the filtering panels, which will allow
unfiltered air to enter the induction system.
Any filter that appears doubtful shall be replaced.
2-7

e. Install filter in air box with gasket on aft face of
filter frame and with air flow arrow on filter pointed
in the correct direction.
NOTE
Keeping a supply of clean, serviced filters
on hand will speed up air filter servicing.
Refer to figure 2-5.
To service the dry type filter, proceed as follows:
a. Remove filter by releasing the quick-release
fasteners.
NOTE
Use care to-prev-ent-damage-to-filter-element
when cleaning filter with compressed air.
b. Clean filter by blowing with compressed air
(not over 100 psi) from direction opposite of normal
air flow. Arrows on filter case indicate direction of
normal air flow.
CAUTION|
Do not use solvent or cleaning fluids to wash
filter. Use only a water and household detergent solution when washing the filter.
c. After cleaning as outlined in step "b" filter may
be washed, if necessary, in a solution of warm water
and a mild household detergent. A cold water solution may be used.

e. Be sure induction air box and air inlet ducts to
the engine are clean, inspect and install new filter
if filter is damaged.
f. Install filter. Be sure gasket on aft face of
filter is in good condition.
NOTE
An optional air filter installation for the alternate air source (SK 172-21) is available for
Model 172 Series aircraft through the 1966
Model year. Refer to paragraph 12-24A.
2-17A. VACUUM SYSTEM FILTERS keep dust and
dirt from entering the vacuum operated flight instruments. On airplanes NOT equipped with the central
air_filter system (see Section 16), the filters in the
instruments should be replaced every 100-lours-ofoperation and whenever erratic or sluggish responses
are noted with normal suction gage readings. On airplanes equipped with vacuum systems containing a
central air filter, change the filter every 500 hours
of operation and whenever suction gage reading drops
below 4.6 inches of mercury. Change the gyro instrument air filters, when equipped with central air
filter, whenever the gyro instruments are overhauled.
Beginning with the 1967 models and on, different gyro
instruments are used in the vacuum system. These
instruments are not equipped with internal filters.
The new instruments are smaller with a beveled boxtype case. Also, these instruments and related
plumbing are used as service parts.
2-18.

BATTERY servicing Involves adding dis-

tilled water to maintain the electrolyte even with the
NOTE
The filter assembly may be cleaned with corpressed air a maximum of 30 times or it may
be washed a maximum of 20 times. The filter should be replaced after 500 hours of engine operating time or one year, whichever
should occur first. An exception to this is
the dry filter formerly used on Models 180,
182, and 185 (Cessna Part No. 0750038, without a dash number), which should be replaced
after 300 hours or one year. Cessna Part
No. 0750038-4 contains an improved element;
this filter should be replaced after 500 hours
or one year. However, the filter should be replaced at any time it is damaged. A damaged
filter, may have sharp or broken edges in the
filtering panels which would allow unfiltered
air to enter the induction system. Any filter
that appears doubtful shall be replaced.
d. After washing, rinse filter with clear water
until rinse water draining from filter is clear. Allow
water to drain from filter and dry with compressed
air (not over 100 psi).
NOTE
The filtering panels of the filter may become
distorted when wet, but they will return to
their original shape when dry.
2-8

horizontal baffle plate at the bottom of 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 water. Brighten
cables and terminals with a wire brush, then coot
with petroleum jelly before connecting. The battery
box also should be checked and cleaned if any
corrosion is noticed. Distilled water, not acid or
"rejuvenators," should be used to maintain
electrolyte level. Check the battery every 50 hours
(or at least every 30 days), oftener in hot weather.
See Section 17 for detailed battery replacement and
testing.
2-19. TIRES should be maintained at the air pressures specified in the charts in Section 1. When
checking tire pressure, examine tire for wear, cuts,
bruises, and slippage. Remove oil and grease with
soap and water.
NOTE
Recommended tire pressures should be maintained. Especially in cold weather, remember
that any drop in temperature of the air inside
a tire causes a corresponding drop in pressure.
2-20. NOSE GEAR SHOCK STRUT. The nose gear
strut requires periodic checking to ensure that the
strut is filled with hydraulic fluid and is inflated to

the correct air pressure. When servicing the nose
gear strut, proceed as follows:
a. Remove valve cap and release air pressure.
b. Remove valve housing assembly.
c. Telescope strut to its shortest length and fill to
bottom of filler hole with hydraulic fluid.
d. Lift nose of airplane, extend and compress strut
several times to expel any entrapped air, then lower
nose of airplane and repeat step "c."
e. Install valve housing assembly and inflate strut
with nose wheel off ground (strut extended). Shock
strut pressures are listed in Section 1.

If the dampener has a filler plug, refill as follows:
a. Remove dampener from airplane.
b. Remove filler plug and drain all hydraulic fluid
from the dampener, then fill with the amount of
hydraulic fluid specified on the placard.
NOTE
Fill the smaller dampener with 52cc of fluid
and the larger one with 74cc of fluid.
c. Install and safety filler plug and reinstall dampener on airplane.

NOTE
Keep the nose gear shock strut, especially the
exposed portion of the strut piston, wiped off
with a clean dry cloth to remove dust and
grit which may cut the seals in the strut barrel.
Do not wipe the strut with hydraulic fluid, since
this tends to collect even more dust and grit.

2-21. NOSE GEAR SHIMMY DAMPENER (MODELS
150 AND 172). The shimmy dampener should be
serviced at least every 100 hours. The shimmy
dampener must be filled completely with fluid, free
of entrapped air, to serve its purpose. Two types
of shimmy dampeners are used, one of which must
be removed to check fluid level and refill. If the
dampener has a filler plug, refill as follows:
a. Remove filler plug, and turn nose gear in the
direction that places the dampener piston at the end
opposite the filler plug.
b. While holding in this position, fill dampener
with hydraulic fluid and install and safety filler plug.
If the dampener does not have a filler plug, refill as
follows:
a. Remove dampener and pull the fitting end of the
dampener shaft to its travel limit.
b. Fill through the opposite end with hydraulic fluid,
while holding the dampener vertical.
c. Push the shaft upward slowly to seal off the filler
hole, and reinstall the dampener on the airplane. Be
sure to keep the shaft protruding through the filler
hole until the dampener is installed,
NOTE
Keep shimmy dampener, especially the exposed portions of the dampener piston shaft,
clean to prevent collection of dust and grit
which could cut the seals in the dampener
barrel. Wipe dampener and shaft with a
clean cloth. Do not use a cloth saturated
with hydraulic fluid, since this tends to
collect even more dust and grit.
2-21A. NOSE GEAR SHIMMY DAMPENER (MODEL
182 PRIOR TO 1967). The shimmy dampener should
be serviced at least every 100 hours. Two sizes of
shimmy dampeners are used. The shimmy dampener
on the Model 182 is subjected to more heat than other
models, and a small airspace is needed for fluid expansion. Both shimmy dampeners must be removed
for filling, since each must be filled with a specific
amount of hydraulic fluid.

If the dampener does not have a filler plug, refill as
follows:
a. Remove dampener and pull the fitting end of the
dampener shaft to its travel limit. Drain all fluid
from the dampener.
b. Fill through the opposite end with the amount of
hydraulic fluid specified on the placard, while holding
the dampener vertical.
NOTE
Fill the smaller dampener with 52cc of fluid
and the larger one with 74cc of fluid.
c. Push the shaft upward slowly to seal off the
filler hole, and reinstall the dampener on the airplane. Be sure to keep shaft protruding through the
filler hole until dampener is installed.
d. Observe "note" in preceding paragraph.
2-21B. NOSE GEAR SHIMMY DAMPENER (1967
MODEL 182 AND ON). The Model 182 is equipped
with a different shimmy dampener which contains a
compensating meahcnism within the hollow piston
rod for thermal expansion and contraction of the
hydraulic fluid. The shimmy dampener must be
filled completely with hydraulic fluid, free of entrapped air with the compensating piston bottomed.
Beginning with serial number 18258404 and on, the
filling procedure is changed. It is recommended
that aircraft prior to serial number 18258404 have
the excessive fluid removed from the compensating
mechanism as follows:
a. Remove shimmy dampener from the aircraft.
b. While holding the shimmy dampener in a vertical position with the filler plug pointed upward,
loosen the filler plug.
c. Allow the spring to bottom out the floating
piston inside the shimmy dampener rod.
d. When the fluid stops flowing, insert a length of
stiff wire through the air bleed hole in the setscrew
at the end of the piston rod until it touches the floating piston. The depth of insertion should be 3-13/16
inches.
NOTE
If the wire insertion is less than 3-13/16 inches,
the floating piston is lodged in the shaft. If the
wire cannot be used to free the piston, the rod
assembly and piston should be replaced.

2-9

e. Tighten filler plug and install shimmy dampener
in aircraft.
To service the shimmy dampener proceed as follows:
a. Remove shimmy dampener from aircraft.
b. Remove filler plug from dampener.
c. Submerge dampener in clean hydraulic fluid and
work dampener shaft in and out to remove any entrapped air and ascertain complete filling.
NOTE
Be sure that the shimmy dampener and hydraulic fluid at 70 ° to 80 ° while filling the shimmy
dampener.

electrostatic charge which attracts dust. Oil and
grease may be removed by rubbing lightly with a
soft cloth moistened with Stoddard solvent. After
washing, the plastic windshield and windows should
be cleaned with an aircraft windshield cleaner. Apply the cleaner with soft cloths, and rub with moderate pressure. Allow the cleaner to dry, then wipe it
off with soft flannel cloths. A thin, even coat of wax,
polished out by hand with clean soft flannel cloths,
will fill in minor scratches and help prevent further
scratching. Do not use a canvas cover on the windshield or windows unless freezing rain or sleet is
anticipated since the cover may scratch the plastic
surface.

d.Install-filler-plug-before-removing-dampenerfrom hydraulic fluid.
NOTE
Be sure to keep the shaft protruding through
barrel at filler end, until the dampener is
installed.
e. Wash dampener in cleaning fluid and wipe dry
with a cloth.
f. Install shimmy dampener on aircraft.
NOTE
Keep shimmy dampener, especially the exposed
portion of the dampener shaft, wiped clean with
a clean, dry cloth to remove dust and grit which
may cut the seals in the dampener barrel. Do
not wipe the shaft with hydraulic fluid, since
this tends to collect even more dirt and grit.
2-22. HYDRAULIC BRAKE SYSTEMS should be
checked and the brake master cylinder refilled as
required at least every 100 hours with hydraulic fluid,
Bleed the brake system of entrapped air whenever
there is a spongy response to the brake pedals.
2-22A. CASTERING AXLE. Check and refill if required per paragraph 5-22H, at each 100-hour inspection.
2-23.

OXYGEN CYLINDER.

2-24.

FACE MASKS.

2-25.

CLEANING.

Refer to Section 15.

2-26. Keeping the aircraft clean is important. Besides maintaining the trim appearance of the airplane,
cleaning lessens the possibility of corrosion and
makes inspection and maintenance easier.
2-27. WINDSHIELD AND WINDOWS should be cleaned carefully with plenty of fresh water and a mild
detergent, using the palm of the hand to feel and dislodge any caked dirt or mud. A sponge, soft cloth,
or chamois may be used, but only as a means of
carrying water to the plastic. Rinse thoroughly,
then dry with a clean moist chamois. Do not rub
the plastic with a dry cloth since this builds up an
2-10

Do not use gasoline, alcohol, benzene,-acetone,
carbon tetrachloride, fire extinguisher fluid,
de-icer fluid, lacquer thinner or glass window
cleaning spray. These solvents will soften
and craze the plastic.
2-28. PLASTIC TRIM. The instrument panel,
plastic trim, plastic control wheels, and control
knobs need only be wiped off with a damp cloth. Oil
and grease on the control wheel and control knobs
can be removed with a cloth moistened with Stoddard
solvent. Volatile solvents, such as mentioned in
paragraph 2-27, must never be used since they
soften and craze the plastic.
2-29. ALUMINUM SURFACES require a minimum of
care, but should never be neglected. The airplane
may be washed with clean water to remove dirt, and
with carbon tetrachloride or other 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 aircraft products.
2-30. PAINTED SURFACES. The painted exterior
surfaces of the airplane, under normal conditions,
require a minimum of polishing or buffing. Approximately 15 days are required for acrylic or lacquer
paint to cure completely and approximately 90 days
are required for vinyl paint to cure completely; in
most cases, the curing period will have been completed prior to delivery of the airplane. In the event
that polishing or buffing is required within the curing
period, it is recommended that the work be done by
an experienced painter. 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 cause corrosion or make scratches should never be used. Remove stubborn oil and
grease with a cloth moistened with Stoddard solvent.
After the curing period, the airplane may be waxed
with a good automotive wax. A heavier coating of
wax on the leading edges of the wings and tail and
on the engine nose cap will help reduce the abrasion
encountered in these areas.

2-31. ENGINE COMPARTMENT cleaning is essential to minimize any danger of fire, and for proper
inspection of components. The engine and engine
compartment may be washed down with a suitable
solvent, then dried thoroughly.

2-34. WHEELS should be washed off periodically
and examined for corrosion, chipped paint, and
cracks or dents in the wheel castings. Sand smooth,
prime, and repaint minor defects.
2-35.

LUBRICATION.

CAUTION
Particular care should be given to electrical
equipment before cleaning. Solvent should
not be allowed to enter magnetos, starters,
alternators, voltage regulators, and the like.
Hence, these components should be protected
before saturating the engine with solvent.
Any oil, fuel, and air openings on the engine
and accessories should be covered before
washing the engine with solvent. Caustic
cleaning solutions should be used cautiously
and should always be properly neutralized
after their use.
2-32. UPHOLSTERY AND INTERIOR cleaning prolongs the life of upholstery fabrics and interior trim.
To clean the interior:
a. Empty the ash trays.
b. Brush out or vacuum clean the carpeting and
upholstery to remove dirt.
c. Wipe off leather, Royalite, and plastic surfaces with a damp cloth.
d. Soiled upholstery fabrics and carpeting may be
cleaned with a foam-type detergent, used according to the manufacturer's instructions,
e. Oily spots and stains may be cleaned with
household spot removers, used sparingly. Before
using any solvent, read the instructions on the container and test it on an obscure place in the fabric
to be cleaned. Never saturate the fabric with a
volatile solvent; it may damage the padding and
backing materials.
f. Scrape off sticky materials with a dull knife,
then spot clean the area.
2-33. PROPELLERS should be wiped off occasionally with an oily cloth to clean off grass and bug
stains. In salt water areas this will assist in
corrosion-proofing the propeller.

2-36. Lubrication requirements are shown on the
Lubrication Chart (figure 2-4). Before adding grease
to grease fittings, wipe off all dirt. Lubricate until
new grease appears around parts being lubricated,
and wipe off excess grease. The following paragraphs supplement this figure by adding details.
2-37. NOSE GEAR TORQUE LINKS. The nose gear
torque links should be lubricated at least every 50
hours, or oftener when operating in dusty areas.
Under extremely dusty conditions, daily lubrication
is recommended.
2-38. RUDDER TRIM WHEEL THREADS (MODEL
185 SERIES). Spray the rudder trim wheel threads
with Electrofilm Lubri-Bond "A" which is available
in aerosol spray cans.
2-39. TACHOMETER DRIVE SHAFT.
tion 16 for lubrication.

Refer to Sec-

2-40. WHEEL BEARING LUBRICATION. It is now
recommended that nose and main wheel bearings be
cleaned and repacked at the first 100-hour inspection
and at each 500-hour inspection thereafter. If more
than the usual number of take-off and landings are
made, extensive taxiing is required, or the airplane
is operated in dusty areas or under seacoast conditions, it is recommended that cleaning and lubrication of wheel bearings be accomplished at each 100hour inspection.
2-41. CASTERING AXLE. Lubricate pivot pin during assembly. Also lubricate the pivot pin through
the grease fittings after assembly and at each 100hour inspection.

SHOP NOTES:

2-10A/2-10B

DAILY

3 FUEL TANK FILLERS
Fill after each flight. Keep full to retard condensation.

Refer to paragraph 2-14 for details.

FUEL TANK SUMP DRAINS
If quick-drain valves are installed, drain off any water and sediment before the first flight
of the day.

OXYGEN CYLINDER
Check for anticipated requirements before each oxygen flight. Refer to Section 15 for details.

8 PITOT AND STATIC PORTS
Check for obstructions before first flight of the day.

OIL DIPSTICK
Check on preflight. Add oil as necessary.

Refer to paragraph 2-16 for details.

18 FUEL STRAINER
Drain off any water and sediment before the first flight of the day.

SERVICING
Figure 2-4. Servicing and Lubrication (Sheet 1 of 7)
2-11

50 HOURS

7 BATTERY

Check level of electrolyte. Check at least every 30 days, oftener in hot weather. Refer
to paragraph 2-18 for details.

14 19 ENGINE OIL SYSTEM

Change engine oil and external filter element. Without external filter, change oil and
clean oil screen EVERY 25 HOURS. Reduce these intervals under severe operating
conditions. Refer to paragraph 2-16 for details.

INDUCTION AIR FILTER
Service oftener under dusty conditions. Refer to paragraph 2-17 for details.

-15-SHIMMY-DAMPENER_(1_9_67 MODEL 182)

Check shimmy dampener compensating mechanism.

Refer to-paragraph-2-21B-for-details.

100 HOURS

FUEL/AIR CONTROL UNIT SCREEN
Remove and clean screen in bottom of fuel/air control unit on fuel injection engines,
then reinstall and safety the screen.

2 GYRO INSTRUMENT AIR FILTERS

If not equipped with central air filter, replace every 100 hours and when erratic or sluggish
responses are noted with normal suction gage readings. Refer to paragraph 2-17A for details.

4 FUEL LINE DRAIN PLUGS OR VALVES
Remove plugs and drain off any water and sediment.
aircraft use drain valves instead of drain plugs.

Reinstall and resafety plugs.

Some

FUEL TANK SUMP DRAINS
If quick-drain valves are not installed, remove plugs and drain off any water and sediment.
Reinstall and resafety plugs.
BRAKE MASTER CYLINDERS
Check fluid level and refill as required with hydraulic fluid.

15 SHIMMY DAMPENER

Check fluid level and refill as required with hydraulic fluid. Refer to paragraphs 2-21
and 2-21A for details.

18 FUEL STRAINER
Disassemble and clean strainer bowl and screen.
9 CASTERING AXLE
Check and refill if required.

Refer to paragraph 2-22A for details.

VACUUM SYSTEM OIL SEPARATOR
Remove, flush with solvent, and dry with compressed air.

SUCTION RELIEF VALVE SCREEN OR FILTER
Check inlet screen or filter for cleanliness. Remove, flush with solvent, and dry with
compressed air to clean. On Garwin valves, remove retaining ring to remove screen.
On filter-equipped valves, replace garter filter at engine overhaul periods.

SERVICING
Figure 2-4.
2-12

Servicing and Lubrication (Sheet 2 of 7)

500 HOURS

20 VACUUM SYSTEM CENTRAL AIR FILTER
Replace central air filter every 500 hours and when suction gage reading drops below
4.6 inches of mercury. Refer to paragraph 2-17A for details.

AS REQUIRED
10

TIRES

Maintain proper tire inflation as listed in the charts in Section 1. Also refer to
paragraph 2-19.

GROUND SERVICE RECEPTACLE (PRIOR TO 1967 MODELS)
Connect to 12-volt, DC, negative-ground power unit for cold weather starting and
lengthy ground maintenance of the electrical system. Master switch should be turned
on before connecting a generator type external power source; it should be turned off
before connecting a battery type external power source. Refer to paragraph 12-14.

CAUTION
Be certain that the polarity of any external power source or batteries
is correct (positive to positive and negative to negative). A polarity
reversal will result in immediate damage to semiconductors in the
airplane's electronic equipment.

GROUND SERVICE RECEPTACLE (1967 MODELS AND ON)
Connect to 12-volt, DC, negative-ground power unit for cold weather starting and
lengthy ground maintenance of the airplane's electrical equipment with the exception
of electronic equipment. Master switch should be turned on before connecting a
generator type or battery type external power source. Refer to paragraph 12-14A.
NOTE
The ground power receptacle circuit incorporates a polarity reversal
protection. Power from the external power source will flow only if the
ground service plug is connected correctly to the airplane.

NOSE GEAR SHOCK STRUT
Keep strut filled and inflate to correct pressure. Refer to paragraph 2-20 for details.

SERVICING
Figure 2-4. Servicing and Lubrication (Sheet 3 of 7)
2-13

FREQUENCY (HOURS)

METHOD OF APPLICATION

GUN

CAN

WHERE NO INTERVAL IS SPECIFIED,
LUBRICATE AS REQUIRED AND
WHEN ASSEMBLED OR INSTALLED.

(FOR POWDERED
GRAPHITE)

NOTE
The military specifications listed are not mandatory, but are intended as
guides in choosing satisfactory materials. Products of most reputable
manufacturers meet or exceed these specifications.
LUBRIC-ANTS
PG - MIL-G-6711
GG - MIL-G-7711
GA - MIL-G-25760
GH - MIL-G-23827
GL - MIL-G-21164
OG - MIL-L-7870
P L - W- P- 236
GS

POWDERED GRAPHITE
GENERAL PURPOSE GREASE
AIRCRAFT WHEEL BEARING GREASE
AIRCRAFT AND INSTRUMENT GREASE
HIGH AND LOW TEMPERATURE GREASE
GENERAL PURPOSE OIL
PETROLATUM
SIL-GLYDE (OR EQUIVALENT)

REFER TO
ALSO
.-SHIMMY
DAMPENER
PIVOTS

-- --

REFER TO. PARAGRAPH 2-40X

STEERING SYS-

TEM NEEDLE
BEARINGS

GGA
NOSE GEAR

MAIN GEAR

WHEEL BEARINGS

TAIL GEAR

FLAP BELLCRANK
NEEDLE BEARINGS

LUBRICATION
Figure 2-4.
2-14

Servicing and Lubrication (Sheet 4 of 7)

CONTEEDLE
COLUMEARN
ROLLERS
/

W
NEEDLE BEARINGS

KWHEEL

OILITE BEARINGS
CONTROL T
CONTROL
SHAFT
UNIVERSALS
NEEDLE BEARINGS

NEEDLE BEARING

CONTROL COLUMN
CONTROL "T"

CONTROL

WHEEL SHAFT
INIVERSALS

USHINGS AND
OILITE BEARINGS

CONTROL "Y"
NEEDLE BEARINGS

CONTROL "Y"

BATTERY
PARKING BRAKE

LUBRICATION
Figure 2-4. Servicing and
Lubricatio

(Sheet 5 of 7)
2-15

OILITE BEARINGS
(RUDDER BAR ENDS)

NEEDLE

ALL LINKAGE
POINT PIVOTS

SCREW JACK
THREADS
ELECTRIC F7APDRIVE MECHANISM

BEARING BLOCK
HALVES

RUDDER BARS AND PEDALS
RELEASE BUTTON &
RATCHET LATCH

O06

ALL PIANO
HINGES
NEEDLE BEARINGS
FLAP LEVER

ELEVATOR TRIM
TAB ACTUATOR
HARTZELL
PROPELLER
GL
STABILIZER ACTUATORS
* REFER TO FIGURE 14-5 FOR A
LIST OF APPROVED GREASES.

LUBRICATION
Figure 2-4. Servicing and Lubrication (Sheet 6 of 7)
2-16

SPRING-LOADED
FRICTION STOPS

ALL TRIM WHEEL
OILITE BEARINGS

ALL TRIM WHEEL
NEEDLE BEARINGS

GH
CABIN DOOR WINDOW
INSERT GROOVES

REFER TO PARAGF. PH 2-38
FOR DETAILS

ALSO REFER TO
PARAGRAPH 2-41
MODEL 185 RUDDER TRIM
WHEEL THREADS
CASTERING AXLE PIVOT PIN

WING FLAP INDICATOR

NOTES
Sealed bearings require no lubrication.
McCauley propellers are lubricated at overhaul and require no other lubrication.
Do not lubricate roller chains or cables except under seacoast conditions.
dry cloth.

Wipe with a clean,

Lubricate unsealed pulley bearings, rod ends, Oilite bearings, pivot and hinge points, and any
other friction point obviously needing lubrication, with general purpose oil every 1000 hours or
oftener if required.
Paraffin wax rubbed on seat rails will ease sliding the seats fore and aft.
Lubricate door latching mechanism with MIL-G-7711 general purpose grease, applied sparingly
to friction points, every 1000 hours or oftener if binding occurs. No lubrication is recommended
on the rotary clutch.

LUBRICATION
Figure 2-4.

Servicing and Lubrication (Sheet 7 of 7)
2-17

HANDLE --

HOLDER BRACKET
2 REQD
MATERIAL: (. 040)
2024-T4 CLAD

/,/

.50 FLANGE

j^^
tA~~

'~'(j

BBEND

D^^~~
^~

RADI .09

~.75.

BEND EDGES OF BOTTOM
AND LID .50 FLANGE

Ft /

gWELD
\

/~g
^^c

^/-^'c

1. IBOTTOM

ENDS A8 REQD

1.62

48 00
LI

1.25

3. 0
''v

^**?; :

^ANGLE

.
2-^

>1 8^

.....
^^^^^ IMATERIAL

1. 00 x

/DRILL

/
.

00 xI /8(ORBQUIVx
1/4 (.250) DRAIN HOLES
4 INCH CENTER
\/

\----BOX ASSEMBLY
FOB BOTTOM AND ENDS

MS20470AD4 RIVET - AS REQD ON HINGE

154.0

15.D

\ ^< ^

MS20470AD3 RIVET - AS REQD

12.0

Figure 2-5. Construction of Induction Air Filter Servicing Box
2-18

1.62

INSPECTION
To avoid repetition throughout the inspection, general points to be checked are given below. In the inspection,
only the items to be checked are listed; details as to how to check, or what to check for, are excluded. Theinspection covers several different models. Some items apply only to specific models, and some items are
optional equipment that may not be found on a particular airplane. Check FAA Airworthines Directive
and
Cessna Service Letters for compliance at the time specified by them. Federal Aviation Regulations require
that all civil aircraft have a periodic (annual) inspection as prescribed by the administrator, and performed by a
person designated by the administrator. The Cessna Aircraft Company recommends a 100-hour periodic inspection for the airplane.
CHECK AS APPLICABLE:
MOVABLE PARTS 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 tensions.
FLUID LINES AND HOSES for: leaks, cracks, dents, kinks, chafing, proper radius, security,
corrosion, deterioration, obstructions, and foreign matter.
METAL PARTS for: security of attachment, cracks, metal distortion, broken spotwelds, corrosion,
condition of paint, and any other apparent damage.
WIRING for: security, chafing, burning, defective insulation, loose or broken terminals, heat deterioration, and corroded terminals.
BOLTS IN CRITICAL AREAS for: correct torque in accordance with the torque values given in the
chart in Section 1, when installed or when visual inspection indicates the need for a torque check.
FILTERS, SCREENS, AND FLUIDS for: cleanliness, contamination and/or replacement at specified
intervals.
AIRPLANE FILE.
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 United States Federal Aviation Regulations. Since the regulations of other nations may
require other documents and data, owners of exported aircraft should check with their own aviation officials
to determine their individual requirements.
To be displayed in the airplane at all times:
1.
Aircraft Airworthiness Certificate (Form FAA 1362B).
2.
Aircraft Registration Certificate (Form FAA 500A).
3.
Aircraft Radio Station License, if transmitter installed (Form FCC 404-2).
To be carried in the airplane at all times:
1. Weight and Balance, and associated papers (Latest copy of the Repair and Alteration
Form, Form FAA 337, if applicable).
2. Aircraft Equipment List.
To be made available upon request:
1. Aircraft Log Book and Engine Log Book.
ENGINE RUN-UP.
Before beginning the step-by-step inspection, start, run up, and shut down the engine in accordance with
instructions in the Owner's Manual. During the run-up, observe the following, making note of any discrepancies or abnormalities:
1.
Engine temperatures and pressures.
2.
Static rpm.
3.
Magneto drop (See Owner's Manual).
4.
Engine response to changes in power.
5. Any unusual engine noises.
6.
Propeller response (See Owner's Manual).
7.
Fuel tank selector and/or shut-off valve; operate engine on each tank position and off position
long enough to make sure the valve functions properly.
8.
Idling speed and mixture; proper idle cut-off.
9. Alternator and ammeter.
10. Suction Gage.
11.
Fuel flow indicator.
After the inspection has been completed, an engine run-up should again be performed to ascertain that any
discrepancies or abnormalities have been corrected.
2-19

SCOPE AND PREPARATION.
CONTINENTAL ENGINE:
If the engine is equipped with an external oil filter, change engine oil and filter element at 50-hour intervals.
If the engine is NOT equipped with an external oil filter, change engine oil and clean the oil screen EVERY 25
HOURS.
"BLUE-STREAK" (Lycoming) ENGINE:
If the engine is NOT equipped with an external oil filter, change engine oil and clean oil screens at 50-hour
intervals. If the engine is equipped with an external oil filter, the engine oil change intervals may be extended
to 100-HOUR intervals providing the external filter element is changed at 50-HOUR intervals.
The 50-hour inspection includes a visual check of the engine, propeller, and aircraft exterior for any apparent
damage or defects; an engine oil change as required above; and accomplishment of lubrication and servicing
requirements. Remove propeller spinner and engine cowling, and replace after the inspection has been completed.
The 100-hour (or annual) inspection includes everything in the 50-hour inspection, and oil change as required
above. Also loosen or remove the fuselage, wing, empennage, and upholstery inspection doors, plates, and
fairings only as necessary-to-perform-a-thorough,-searchinginspection of the aircraft. Replace after the
inspection has been completed.

NOTE
Numbers appearing in the "AS SPECIFIED" column refer
to the data listed at the end of the inspection chart.

AS SPECIFIED
EACH 100 HOURS
PROPELLER.

EACH 50 HOURS

Spinner and spinner bulkhead--------------------------------------

Blades------- ---------------------------

Hub --------------------------------------------

Lubrication (Hartzell)--------------------------------------------------------

Bolts and/or nuts----------------------------------------

Governor and control---------------------------------

----

.
-

------------------------------------------

ENGINE COMPARTMENT.
Check for evidence of oil and fuel leaks, then clean entire engine and compartment, if needed,
prior to inspection.

2-20

Engine oil, screen, filler cap, dipstick, drain plug and external filter element-----------

Oil cooler-----

Induction air filter (Also see paragraph 2-17. ) ----------------------

-- ------------------------------

----------------------------------

AS SPECIFIED
EACH 100 HOURS
EACH 50 HOURS
4. Induction airbox, air valves, doors, and controls ........................................
5. Cold and hot air hoses ..............................................................
6. Engine baffles .....................................................................
7. Cylinders, rocker box covers, and push rod housings ....................................
8. Crankcase, oil pan, reduction gear housing, accessory section and front crankshaft seal .....

9. All lines and hoses .................................................................
10. Intake and exhaust systems (Also see paragraph 12-101) ...............................
11. Ignition harness ...................................................................
12. Spark plugs and compression check ..................................................
13. Crankcase and vacuum system breather lines .........................................
14. Electrical wiring ....................................................................
15. Vacuum pump and oil separator, and relief valve .......................................
16. Vacuum relief valve screen or filter

..................................................

17. Engine controls and linkage ........................................................

18. Engine shock mounts, engine mount structure, and ground straps ........................

19. Cabin heater valves, doors and controls ...............................................
20. Starter, solenoid and electrical connections, and engagement lever .......................

21. Starter brushes, brush leads and commutator ..........................................
22. Generator or Alternator, drive belt, pulley, and electrical connections ......................

23. Generator or Alternator brushes, brush leads, commutator or slip ring .....................
24. Voltage regulator mounting and electrical leads ....................

.....................

25. Magnetos (externally) and electrical connections .......................................
*

26. Bendix magneto breaker compartment and timing (Also see paragraph 12-77) ..............
27. Slick magneto timing ...............................................................
28. Slick magneto breaker compartment (Also see paragraphs 12-71 and 12-71 E) .....

........

6
6

29. Fuel injection fuel-air control unit, fuel pump, fuel manifold valve, fuel lines, and nozzles......
30. Fuel-air control unit screen ..........................................................

Revision 1
© Cessna Aircraft Company

2-21
Aug 4/2003

AS SPECIFIED
EACH 100 HOURS
EACH 50 HOURS
31. Carburetor

........................................................................

32. Firewall .........................................................................

33. Engine cowling ....................................................................

34. Cowl flaps and control ..............................................................

FUEL SYSTEM
1. Fuel strainer, drain valve, and control .................................................

2. Fuel strainer screen and bowl ........................................................
3. Electric fuel pump, throttle switch, and electric connections ..............................

.
.

4. Fuel tanks, fuel accumulator tank, fuel lines, drains, filler caps, and placards ...............

5. Drain fuel and check tank interior, attachment and outlet screens .........................
6. Fuel vents and vent valves .........................................................

7. Fuel selector and/or shut-off valve and placards ........................................

8. Fuel quantity gages and transmitter units ..............................................

9. Engine primer .....................................................................

10. Vapor return line and check valve ....................................................

11. Perform a fuel quantity indicating system operational test. Refer to Section 16
for detailed accomplishment instructions. .............................................

12. For airplanes equipped with an engine that uses a carburetor, drain fuel from
carburetor bowl and check for fuel contaminants. Refer to Cessna Service Bulletin
SEB99-19, Engine Carburetor Fuel Inspection (or latest revision) for detailed
accomplishment instructions ........................................................
13. Fuel injection nozzles ...............................................................

14
15

LANDING GEAR
1. Brake fluid, lines and hoses, linings, disc and clips, brake assemblies and master cylinders ..

2. Main gear wheels, wheel bearings, step and spring strut, tires, and fairings ................

3. Main and nose gear wheel bearing lubrication (Refer to paragraph 2-40) ...................
4. Torque link lubrication (Refer to paragraph 2-36) .......................................

5. Tailgear lubrication and nose gear strut servicing .......................................

6. Nose gear shimmy dampener servicing ...............................................
7. Tailwheel friction check (Refer to paragraph 5-60) ......................................
8. Nose gear wheels, wheel bearings, strut, steering system,
shimmy dampener, tire, fairing, and torque links ........................................
9. Tailwheel, tire, wheel bearings, steering system, anti-swivel mechanism,
tailwheel locking system, cables, and spring tube .......................................

* 10
*

10. Parking brake system ..............................................................
2-22

D637-1-13 TemDorarv Revision Number i6 - APr 5/2004
© Cessna Aircraft Company

AS SPECIFIED
EACH 100 HOURS
EACH 50 HOURS
AIRFRAME
1. Aircraft exterior ...................................................................

2. Aircraft structure ...................................................................
3. Windows, windshield, and doors .....................................................
4. Seat stops, seat rails, upholstery, structure and seat mounting ............................
5. Safety belts and attaching brackets ..................................................

6. Control bearings, sprockets, pulleys, cables, chains and turnbuckles ......................
7. Control lock, control wheel and control mechanism .....................................
8. Instruments and markings ...........................................................
9. Gyro filter and central air filter (Also see paragraph 2-17A) ...............................

10. Magnetic compass compensation ....................................................

11. Instrument wiring and plumbing ......................................................
12. Instrument panel, shock mounts, ground straps, cover, decals and labeling ................
13. Defrosting, heating and ventilating systems and controls .........

...................

14. Cabin upholstery, trim, sun visors and ashtrays .........................................
15. Area beneath floor, lines, hoses, wires and control cables ................................
16. Electrical horns, lights, switches, circuit breakers, fuses, and spare fuses ..................
17. Exterior lights ..............................................................

........

18. Pitot and static systems .............................................................
19. Stall warning sensing unit and pitot and stall warning heaters .............................
20. Radios and radio controls ...........................................................
21. Radio antennas ...................................................................
22. Battery, battery box and battery cables ................................................
23. Battery electrolyte level (Also see paragraph 2-18) ......................................
24. Oxygen system ...................................................................
25. Oxygen supply, masks, and hoses ...................................................

CONTROL SYSTEMS
In addition to the items listed below, always check for correct direction of movement,
correct travel and correct cable tension.
1. Cables, terminals, pulleys, pulley brackets, cable guards, turnbuckles and fairleads .........

Revision 1

2-23
0 Cessna Aircraft Company

Aug 4/2003

Ab b~iMAIW

EACH 100 HOURS
EACH SO HOURS

2. Chains, terminals, sprockets and chain guards .....................

3. Trim control wheels, indicators, actuator, and bungee ..................

4. Travel stops ....................................

5. All decals and labeling................................
6. Flap control lever latch, flap rollers and tracks, flap position transmitter and
linkage, flap position indicator, and flap electric motor and transmission ..........

7. Elevator downspring system .............................

8. Rudder pedal assemblies and linkage .........................

9. Skin and structure of control surfaces and trim tabs ...................
10. Balance weight attachment..............................

0
16

SPECIFIED
INTERVAL
1Each 25 hours, if NOT equipped with an external filter.

2 Replace paper media filters per paragraph 2-17.
3 Each 1000 hours, or to coincide with engine overhauls, replace garter-type filters.
4 Starters and generators each 200 hours; alternators, each 500 hours.
5 First 25 hours, each 100-hour inspection thereafter.

6 Check timing each 200 hours. Check breaker compartment each 500 hours, unless timing is off (except on
the Slick Model 4001 magneto).0

7 Each 1000 hours, or to coincide with engine overhauls.
8 First 100 hours, each 500 hours thereafter.
9 Without temperature-compensating mechanism, service every 100 hours; with temperature-compensating
10
11

12
13
14
15

mechanism, check at 50-hour intervals. (See paragraph 2-21 and 2-21 A)
First four 25 hours, each 100 hours thereafter.
Central filter each 500 hours and gyro filters at overhaul; gyro filters each 100 hours without central filter.
Anticipated requirements before each oxygen flight. Also see Section 15.
Fuel quantity indicating system operational test is required every 12 months. Refer to Section 16 for
detailed accomplishment instructions.
Drain fuel from carburetor bowl and check for fuel contaminants once every12 months. Refer to
Cessna Service Bulletin SEB99-1 9, Engine Carburetor Fuel Inspection (or latest revision) for detailed
accomplishment instructions
At the first 100-hour inspection on new, rebuilt or overhauled engines, remove and clean the fuel injection
nozzles. Fuel nozzles must be cleaned at 300-hour intervals or more frequently if fuel stains are found.

16 For 180 and 185 airplanes: Each 1000 hours, measure the amount of free play between the horizontal
stabilizer and the fuselage. To measure the free play:
A. Set the trim wheel to the takeoff position.
B. Lift up on the horizontal stabilizer forward spar adjacent to the fuselage and measure the free play
between the front spar of the stabilizer and the fuselage. Do this procedure again on the opposite side
of the fuselage.
C. The maximum permitted free play is 0.01 9 inch with a maximum difference between the two sides of
the stabilizer is 0.01 0 inch.
1. If the free play is 0.01 9 inch or less and within 0.01 0 inch of each side, this inspection is complete,
no more action is necessary.
2-24

D637-1 -13 Temporary Revision 7 - July 1/2007
C Cessna Aircraft Company

D
E.

If the free play is more than the permitted tolerance, remove the horizontal stabilizer and examine the free
play between the top and bottom of each actuator.
3
The maximum actuator free play is 0.019 inch. If an actuator free play is greater than 0.019 inch or 0.010
inch of each side, remove and repair the actuator.
4
If an actuator has 0.01 9 inch or less of free play and is within 0.01 0 inch of each side, examine the attach
brackets and attach hardware for wear.
5
Replace worn attach brackets and hardware.
Install the brackets, hardware, actuators, and horizontal stabilizer as applicable.
Do steps 16. A. thru C. again, as applicable.

D637-1 -13 Temporary Revision 7 - July 1/2007

2-24)
C)Cessna Aircraft Company

(This page intentionally left blank.)

2-24B

D637-1 -13 Temporary Revision 7 -July 1/2007
©Cessna Aircraft Company

2-20.

COMPONENT TIME LIMITS
1. General
A. Most components listed throughout Section 2 should be inspected as detailed elsewhere
in this section and repaired, overhauled or replaced as required. Some components,
however, have a time or life limit, and must be overhauled or replaced on or before the
specified time limit.
NOTE:

The terms overhaul and replacement as used within this section are defined as
follows:
Overhaul - Item may be overhauled as defined in FAR 43.2 or it can be
replaced.
Replacement - Item must be replaced with a new item or a serviceable item that
is within its service life and time limits or has been rebuilt as defined in FAR
43.2.

B. This section provides a list of items which must be overhauled or replaced at specific
time limits. Table 1 lists those items which Cessna has mandated must be overhauled or
replaced at specific time limits. Table 2 lists component time limits which have been
established by a supplier to Cessna for the supplier's product.
C. In addition to these time limits, the components listed herein are also inspected at regular
time intervals set forth in the Inspection Charts, and may require overhaul/replacement
before the time limit is reached based on service usage and inspection results.
2. Cessna-Established Replacement Time Limits
A. The following component time limits have been established by The Cessna Aircraft
Company.
Table 1: Cessna-Established Replacement Time Limits
COMPONENT

REPLACEMENT TIME

OVERHAUL

Restraint Assembly Pilot,
Copilot, and Passenger
Seats

10 years

Trim Tab Actuator

1,000 hours or 3 years,
whichever occurs first

YES

Vacuum System Filter

500 hours

Vacuum System Hoses

10 years

Pitot and Static System
Hoses

10 years

Vacuum Relief/Regulator
Valve Filter (If Installed)

500 hours

Engine Compartment
Flexible Fluid Carrying
Teflon Hoses (CessnaInstalled) except Drain

10 years or engine overhaul,
whichever occurs first
(Note 1)

Hoses (Drain hoses are
replaced on condition)
Revision 1

2-25
© Cessna Aircraft Company

Aug 4/2003

COMPONENT

REPLACEMENT TIME

OVERHAUL

Engine Compartment
Flexible Fluid Carrying
Rubber Hoses (CessnaInstalled) except Drain
Hoses (Drain hoses are
replaced on condition)

5 years or engine overhaul,
whichever occurs first.
(Note 1)

Engine Air Filter

500 hours or 36 months,
whichever occurs first
(Note 9)

Engine Mixture, Throttle, and
Propeller Controls

At engine TBO

Engine Driven Dry Vacuum
Pump Drive Coupling (Not
lubricated with engine oil)

6 years or at vacuum pump
replacement, whichever
occurs first

Engine Driven Dry Vacuum
Pump (Not lubricated with
engine oil)

500 hours
(Note 10)

Standby Dry Vacuum Pump

500 hours or 10 years,
whichever occurs first
(Note 10)

Supplier-Established Replacement Time Limits
A.

The following component time limits have been established by specific suppliers and are
reproduced as follows:
Table 2: Supplier-Established Replacement Time Limits
COMPONENT

REPLACEMENT TIME

OVERHAUL

ELT Battery

Note 3

Vacuum Manifold

Note 4

Magnetos

Note 5

YES

Engine

Note 6

YES

Engine Flexible Hoses
(Lycoming and TCM
Installed)

Note 2

Auxiliary Electric Fuel Pump

Note 7

YES

Propeller

Note 8

YES

2-26
© Cessna Aircraft Company

Revision 1
Aug 4/2003

NOTES:
Note 1: This life limit is not intended to allow flexible fluid-carrying Teflon or rubber hoses in a
deteriorated or damaged condition to remain in service. Replace engine compartment flexible
Teflon (AE3663819BXXXX series hose) fluid-carrying hoses (Cessna installed only) every ten
years or at engine overhaul, whichever occurs first. Replace engine compartment flexible
rubber fluid-carrying hoses (Cessna installed only) every five years or at engine overhaul,
whichever occurs first (this does not include drain hoses). Hoses which are beyond these
limits and are in a serviceable condition, must be placed on order immediately and then be
replaced within 120 days after receiving the new hose from Cessna.
Note 2: For Textron Lycoming engines, refer to latest Textron Lycoming Engine Service Bulletins.
For TCM engines, refer to Teledyne Continental Service Bulletin SB97-6, or latest revision.
Note 3: Refer to FAR 91.207 for battery replacement time limits.
Note 4: Refer to Airborne Air & Fuel Product Reference Memo No. 39, or latest revision, for
replacement time limits.
Note 5: For airplanes equipped with Slick magnetos, refer to Slick Service Bulletin SB2-80C, or latest
revision, for time limits.
For airplanes equipped with TCM/Bendix magnetos, refer to Teledyne Continental Motors
Service Bulletin No. 643, or latest revision, for time limits.
Note 6: Refer to Teledyne Continental Service Information Letter SIL98-9, or latest revision, for time
limits.
Note 7: Refer to Cessna Service Bulletin SEB94-7 Revision 1/Dukes Inc. Service Bulletin NO. 0003, or
latest revision.
Note 8: Refer to the applicable McCauley or Hartzell Service Bulletins and Overhaul Manual for
replacement and overhaul information.
Note 9: The air filter may be cleaned, refer to Section 2 of this service manual for servicing
instructions. For airplanes equipped with an air filter manufactured by Donaldson, refer to
Donaldson Aircraft Filters Service Instructions P46-9075 for detailed servicing instructions.
The address for Donaldson Aircraft Filters is:
Customer Service
115 E. Steels Corners RD
Stow, OH 44224
Do not overservice the air filter, overservicing increases the risk of damage to the air filter from
excessive handling. A damaged/worn air filter may expose the engine to unfiltered air and
result in damage/excessive wear to the engine.
Note 10: Replace engine driven dry vacuum pump not equipped with a wear indicator every 500 hours
of operation, or replace according to the vacuum pump manufacturer's recommended
inspection and replacement interval, whichever occurs first.
Replace standby vacuum pump not equipped with a wear indicator every 500 hours of
operation or 10 years, whichever occurs first, or replace according to the vacuum pump
manufacturer's recommended inspection and replacement interval, whichever occurs first.
For a vacuum pump equipped with a wear indicator, replace pump according to the vacuum
pump manufacturer's recommended inspection and replacement intervals.
Revision 1
© Cessna Aircraft Company

2-27
Aug 4/2003

SECTION 3
FUSELAGE
TABLE OF CONTENTS
WINDOWS AND WINDSHIELDS .......
Cleaning ...............
Waxing ............
Repairs ........
....
Scratches. ..............
Cracks ...............
WINDSHIELDS. ..............
Removal ...............
Replacement .............
MOVABLE WINDOWS ...........
FIXED WINDOWS .
......
...
Removal of Rear Windows ........
Installation of Rear Windows ......
CABIN DOORS
.......
....
Removal and Installation ........
Cabin Door Weatherstrip ......
Adjustment of Cabin Door .......
Cabin Door Latches ..........
Adjustment of Door Latches ......
Door Lock ...........
BAGGAGE AND LITTER DOORS ......
Removal and Installation .....
SEATS ..................
Individual Seats ............

Page
3-1
3-1
.
3-t
. 3-1
3-1
3-2
3-2
3-2
3-4
3-4
3-4
3-4
3-4
.
3-4
3-4
. 3-4
3-4
3-4
3-15
.
...
3-15
3-15
...
3-15
3-15
3-15

3-1. WINDOWS AND WINDSHIELDS.
3-2.

CLEANING.

(See paragraph 2-25.)

3-3. WAXING will fill in minor scratches in clear
plastic and help protect the surface from further
abrasion. Use a good grade of commercial wax applied in a thin, even coat. Bring the wax to a high
polish by rubbing lightly with a clean, dry flannel cloth.
3-4. REPAIRS. Damagedwindowpanels andwindshield
may be removed and replaced if the damage is extensive. However, certain repairs as prescribed in the
following paragraphs can be made successfully without removing the damaged part from the airplane.
Three types of temporary repairs for cracked plastic
are possible. No repairs of any kind are recommended on highly-stressed or compound curves where the
repair would be likely to affect the pilot's field of
vision. Curved areas are more difficult to repair than
flat areas and any repaired area is both structurally
and optically inferior to the original.surface.
3-5. SCRATCHES on clear plastic surfaces can be
removed by hand-sanding operations followed by
buffing andpolishing, if steps below are followed carefully.
a. Wrap a piece of No. 320 (or finer) sandpaper or
abrasive cloth around a rubber pad or wood block,
Rub the surface around the scratch with a circular
motion, keeping the abrasive constantly wet with clean
water to prevent scratching the surface further. Use
minimum pressure and cover an area large enough to
prevent the formation of "bull's-eyes" or other optical distortions.

Two-Place Seats ...........
Stowable Seats ...........
Power Seats . ..........
.
Repair of Seat Structure. .......
CABIN UPHOLSTERY. ..........
Upholstery Materials and Tools ....
Soundproofing
.
........
.
Cabin Headliner Removal .
......
Cabin Headliner Installation ......
Upholstery Side Panels ........
Windlace (Door Seal) .........
Carpeting .............
Baggage Compartment Upholstery . .
SAFETY BELTS .............
CARGO TIE-DOWN PROVISIONS .....
CARGO PACK ..............
Removal. ..............
Removal of Cowl Flap Baffles and
Control Extensions .
.....
.
Installation of Cargo Pack .......
Installation of Cowl Flap Baffles and
Control Extensions .........
GLIDER TOW HOOK
.
........
REAR VIEW MIRROR. .........
.

3-15
3-15
3-15
3-16
3-26
3-26
3-26
3-26
3-26
3-26
3-26
3-26
3-26
3-28
3-28
3-30
3-30
3-32
3-32
3-32
3-32
3-32

CAUTION
Do not use a coarse grade of abrasive.
is of maximum coarseness.

No. 320

b. Continue sanding operation, using progressively
finer grade abrasives until the scratches disappear.
c. When the scratches have been removed, wash the
area thoroughly with clean water to remove all gritty
particles. The entire sanded area will be clouded with
minute scratches which must be removed to restore
transparency.
d. Applyfresh tallow or buffing compound to a motordriven buffing wheel. Hold the wheel against the plastic
surface, moving it constantly over the damaged area
until the cloudy appearance disappears. A 2000-footper-minute surface speed is recommended to prevent
heating, distortion, or burns.
NOTE
Polishing can be accomplished by hand but it
will require a considerably longer period of
time to attain the same result as produced by
a buffing wheel.
e. When buffing is finished, wash the areathoroughly
and dry it with a soft flannel cloth. Allow the surface
to cool and inspect the area to determine if full transparency has been restored. Then apply a thin coat of
hard wax and polish the surface lightly with a clean
flannel cloth.

3-1

WOOD REINFORCEMENT

ALWAYS DRILL END OF CRACK

SOFT WIRE
LACING

RUBBERSHION

CEMENTED
FABRIC PATCH
TEMPORARY

Figure 3-1.

Repair of Windows and Windshield

NOTE
Rubbing the plastic surface with a dry cloth will
build up an electrostatic charge which attracts
dirt particles and may eventually cause scratching of the surface. After the wax has hardened,
dissipate this charge by rubbing the surface with
a slightly damp chamois. This will also remove
the dust particles which have collected while
the wax is hardening.
f. Minute hairline scratches can often be removed
by rubbing with commercial automobile body cleaner
or fine-grade rubbing compound. Apply with a soft,
clean, dry cloth or imitation chamois.
3-6. CRACKS. (See figure 3-1.)
a. When a crack appears in a panel, drill a hole at
the end of the crack to prevent further spreading. The
hole should be approximately 1/8 inch in diameter,
depending on the length of the crack and thickness of
the material.
b. Temporary repairs to fat surfaces can be effected by placing a thin strip of wood over each side
of the surface and then inserting small bolts through
the wood and plastic. A cushion of sheet rubber or
airplane fabric should be placed between the wood and
plastic on both sides.
c. A temporary repair can be made on a curved
surface by placing fabric patches over the affected
areas. Secure the patches with airplane dope,Speclfication No. MIL-D-5549; or lacquer, Specification
No. MIL-L-7178. Lacquer thinner, Specification
3-2

No. MIL-T-6094 can also be used to secure the patch.
d. A temporary repair can be made by drilling
small holes along both sides of the crack 1/4 to 1/8
inch apart and lacing the edges together with soft wire.
Small-stranded antenna wire makes a good temporary
lacing material. This type of repair is used as a
temporary measure only, and as soon as facilities are
available the panel should be replaced.
3-7. WINDSHIELDS. (See figure 3-2.) Windshields
are single-piece, "free-blown" acrylic plastic panels
set in sealing strips and held by formed retainer
strips riveted to the fuselage. In many aircraft,
a windshield centerstrip supports the center of the
windshield. Various sealants have been used to
prevent leakage around the windshield. However,
Presstite No. 579.6 sealing compound used in conjunction with a felt strip at the top and sides, and
EC-1202 tape (manufactured by the Minnesota Mining
and Mfg. Co., St. Paul, Minnesota used at the-bot-tom of the windshield will give satisfactory results.
If desired, the EC-1202 tape, which is available in
different widths and thicknesses, can be used as a
sealant at all edges of the windshield.
3-8. REMOVAL.
a. Remove the screws and attaching parts at the
windshield centerstrip.
b. Drill out all rivets securing the retainer strip at
the front of the windshield.
c. Remove wing fairings over windshield edges.
d. Pull windshield straight forward, out of side and
top retainers. Remove top retainer if necessary.

NOTE
Presstite No. 579. 6 sealer should be applied to
all edges of windshield where felt sealing strip
(7) is used. This sealer may be used to seal
any leaks around windshield. Where EC-1202
tape (10), manufactured by the Minnesota Mining and Manufacturing Company, St. Paul,
not required.

1.
2.
3.
4.
5.
6.

Inner Centerstrip
Washer
Nut
Washer
Screw
Outer Centerstrip

7.
8.
9.
10.
11.
12.

Felt Seal
Retainer Strip
Windshield
Sealing Tape
Inner Retainer Strip
Outer Retainer Stri:

Figure 3-2. Typical Windshield Installation
3-3

3-9. REPLACEMENT.
a. Apply felt strip and sealing compound or sealing
tape to all edges of windshield to prevent leaks.
b. Reverse steps listed in preceding paragraph to
install a windshield.
c. When installing a new windshield, check the fit
and carefully file or grind away any excess plastic.
d. Use care not to crack windshield when installing.
lf not previously removed, top retainer may be removed if necessary. Starting at an upper corner and
gradually working windshield into position is recommended.
NOTE
Screws and self-locking nuts may be used irstead of the factory installed rivets which
fasten the front retaining strip to the cowl
-deck.Ifat least No. 6 screws are used, no
loss of strength will result.
3-10. MOVABLE WINDOWS. (See figure 3-4.)
Movable windows, hinged at the top, are installed in
some doors. Window assemblies, that is the clear
plastic and frame unit, may be replaced by pulling
the hinge pins and disconnecting the window stop. To
remove the frame from the plastic, it is necessary
to drill out the blind rivets where the frame is
spliced. When replacing a window in a frame, make
sure that the sealing strip and an adequate coating of
Presstite No. 579. 6 sealing compound is used all
around the edges of the plastic panel.
3-11. FIXED WINDOWS. Fixed windows are mounted
in sealing strips and sealing compound, and are held
in place by various retainer strips. To replace the
side windows, remove upholstery and trim panels,
then drill out rivets as necessary to remove the retainer strips.
3-12. REMOVAL OF REAR WINDOWS. The "wraparound" rear windows may be removed as follows:
MODEL 182F (See figure 3-3.)
a. Remove external centerstrip.
b. Remove upholstery as necessary to expose retainer strips securing the window to be replaced.
The window is made in two sections, consisting of
a right and a left half.
c. Drill out rivets as necessary to remove the retainer strips at the top, bottom, and outboard edges
of the window. Do not remove any rivets at the
centerstrip.
d. Slide the outboard edge of the window down,
pulling the inboard edge away from the centerstrip
hat section, then remove. The window may be
flexed slightly if necessary to clear the hat section.
MODEL 182G AND ON (See figure 3-3.) This rear
window is a one-piece window. Merely remove upholstery and retainer strips, then pull window into
the cabin area to remove.
MODELS 150 AND 172 (See figure 3-3.) These rear
windows are one-piece windows. To remove a rear
window on either of these models, use the following
3-4

procedure:
a. Remove external centerstrip.
b. Remove upholstery as necessary to expose retainer strips inside the cabin.
c. Drill out rivets as necessary to remove external
retainer strip along the aft edge of the window.
d. Remove window by lifting aft edge and pulling
window aft. If difficulty is encountered, rivets securing retainer strips inside the cabin may also be
drilled out and the retainer strips loosened or removed.
3-13. INSTALLATION OF REAR WINDOWS. Installation of the "wrap-around" rear windows may be
accomplished by reversing the procedures listed in
paragraph 3-12, observing the following precautions:
a. Check the fit of a new window and carefully file
or grind away any excess plastic.
b. Use care not to crack plastic when installing.
-c--Be-sure-to-usesealing
strips and sealing compound to prevent leaks.
3-14.

CABIN DOORS.

(See figure 3-4.)

3-15. REMOVAL AND INSTALLATION. Removal
of cabin doors is accomplished either by removing
the screws which attach the hinges or by removing
the hinge pins. If the type of door stop which is
connected to the fuselage and the door is used, it
must also be disconnected. Some airplanes are
equipped with removable hinge pins to facilitatedoor
removal. If the permanent hinge pins were removed,
they may be replaced by clevis pins secured with
cotter pins, or new hinge pins may be installed and
"spin-bradded." When fitting a new door, some
trimming of the door skin at the edges and some reforming with a soft mallet may be necessary to
achieve a good fit.
3-16. CABIN DOOR WEATHERSTRIP is cemented
around all edges of the door. New weatherstrip may
be applied after mating surfaces of weatherstrip and
door are clean, dry and free from oil or grease.
Apply a thin, even coat of adhesive to each surface
and allow to dry until tacky before pressing strip in
place. Minnesota Mining and Manufacturing Co. No.
EC-880 cement is recommended.
3-17. ADJUSTMENT OF CABIN DOOR. The cabin
door should be adjusted so the cabin door skin fairs
with the fuselage skin. Slots at the latch strike plate
permit re-positioning of the strike plate. Depth of
latch engagement may be changed by adding or removing washers or shims between the- strike-plate and the
doorpost. Some airplanes contain wedges at the upper
forward edge of the door which aid in preventing air
leaks at this point. They engage as the door is
closed. Several attaching holes are located in the
wedges, and the set of holes which gives best resuits should be selected.
3-18. CABIN DOOR LATCHES. Flush-mounted outside door handles and conventional inside door handles are used to actuate door latches. The Model
150 inside door handles are also flush, similar to
the outside handles. The different types of door
latches are shown in figure 3-5, which may be used

RETAINING WINDOWS

ON ALL MODELS

1.
2.
3.
4.

Seal
Cabin Skin
Retainer
Centerstrip

5. Screw
6. Stringer
7. Right Rear Window
8. Fuselage Skin

9.
10.
11.
12.

Rivet
Left Rear Window
Nutplate
Window

Figure 3-3. Fixed Windows (Sheet 1 of 3)
3-5

MODEL 182G AND ON

1.
2.
3.

Right Side Window
Right Window Skin
Upper Skin

4.
5.
6.
7.

Figure 3-3.
3-6

Upper Retainer
Right Retainer
Aft Retainer
Rear Window

Fixed Windows (Sheet 2 of 3)

8. Left Retainer
9. Left Window Skin
10. Left Side Window

MODEL 150D AND ON

MODEL 172D AND ON

NOTE
Prior to the Model 150D, side
windows were used without
the rear window.

1. Upper Skin
2. Lower Skin
3. Rear Window

4. External Retainer
5. External Centerstrip
6. Screw

Figure 3-3.

7. Felt Seals
8. Side Window
9. Side Window Skin

Fixed Windows (Sheet 3 of 3)
3-7

NOTE.
This is a typical door, details of which
do not apply to all models. Various
models differ in hinge arrangements,
types of door stops used, the method of
upholstery attachment, and other minor
particulars. Some door windows are
not openable.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Upholstery Clip
Upholstery Panel
Wedge
Spring
Window Stop
Window Hinge
Latch Plate
Cabin Door
Window Frame
Window
Washer
Nut
Lock Assembly
Latch Handle

15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.

Rivet
Roll Pin
Spacer
Bracket
Spring
Door Stop Arm
Hinge
Pin or Rivet
Reinforcement
Door Stop Arm
Stop Assembly
Spring-Loaded Plunger
Hinge

Figure 3-4.
3-8

Cabin Doors

2.
3.
4.
5.
6.

Eyebolt
Stud and Eyelet
Hinge Pin
Canvas Panel
Litter Door

8.
9.
10.
11.
12.

Striker Plate
Shiln
Bolt Guide
Roll Pin
Spring

Figure 3-4A.

14.
15.
16.
17.

Bolt
Handle
Baggage Door Opening
Floor Pan

Litter Door
3-9

MODELS 180, 182, AND 185
12

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.

Inside Handle
Retaining Clip
Escutcheon
Spring
Base Plate,
Bearing Plate
Spring
Spring
Latch Bolt
Pull Bar
Outside Handle
Bracket
Latch Strap
Shaft Assembly
Spacer

16.

Spacer

17.
18.
19.
20.
21.

Housing
Catch
Spring (150)
Spring (172)
Outside Handle

22.
23.

Inside Handle
Pan Assembly

24. Bracket
25. Spacer

ALL MODELS PRIOR TO 1966

NOTE
On the Model 172, spring (4) is
currently not being used in order
to reduce friction. Spring may
be removed from earlier models
if desired.

MODELS 150 AND 172
OUTSIDE HANDLE
21
15 I3

2
2

1
3

MODEL 172 INSIDE HANDLE

MODEL 150 INSIDE HANDLE

Figure 3-5. Cabin Door Latches (Sheet 1 of 5)
3-10

ROTARY CLUTCH
MODEL 150 - 1966 AND ON

1.
2.

Outside Handle
Spring

6.
7.

Inside Lock
Mounting Plate

11.
12.

Mounting Structure
Draw Bar

LEFT DOOR LATCH SHOWN

CLOSE position. Temporarily install handle and move
back and forth until spring-loaded position is noted.
Remove handle, re-position with CLOSE mark at
index mark on door (handle approximatelyvertical),
and install. Bolt must clear doorpost, but teeth must
engage when door is closed with handle at CLOSE
position.

ROTARY CLUTCH

MODEL 172 - 1966 AND ON

1.
2.
3.
4.
5.

Retaining Clip
Inside Handle
Index Placard
Retaining Ring
Mounting Plate

6.
7.
8.
9.

Roll Pin
Bolt
Housing
Outside Handle

Figure 3-5. Cabin Door Latches (Sheet 3 of 5)
3-12

10.
11.
12.
13.
14.

Spring
Rotary Clutch
Push Rod
Bearng Plate Assembly
Support

NOTE
Rotary clutch (4) components
are matched upon assembly.
The clutch mechanism, if defective, should be replaced as
a unit.

MODEL 182 - 1966 AND ON

MODEL 180/185 - 1966 AND ON

1. Cover
2. Abrasive Washer
3. Gear

ROTARY CLUTCH INSTALLATIONS

4. Rotary Clutch.
5. Mounting Structure

6. Shim
7. Guide
8. Door Post

Figure 3-5. Cabin Door Latches (Sheet 4 of 5)
3-13

MODELS 180, 182, AND 185 - 1966 AND ON

Handle (9) is marked with OPEN, CLOSE, AND LOCK
positions. The handle must be installed relative to
position of bolt (2), which is spring-loaded to the
CLOSE position. Temporarily install handle and move
back and forth until spring-loaded position is noted.
Remove handle, re-position with CLOSE mark at index
mark on door (handle approximately vertical), and install. Bolt must clear doorpost, but teeth must engage
when door is closed with handle at CLOSE position.
Abrasive pad (5A) and lockplate (5B) were added to
the Model 182 during the 1966 Model-year to aid
adjustment.

1.
2.
3.
4.
5.

Top Plate
Bolt
Side Plate
Base Plate
Plate

5A. Abrasive Pad
5B. Lockplate
6. Bracket
7. Spring
8. Nylon Escutcheon

9. Inside Handle
10. Clip
11. Guide
12. Placard
13. Support

Figure 3-5. Cabin Door Latches (Sheet 5 of 5)
3-14

14.
15.
16.
17.

Push-PullShaft
Push-Pull Bar
Outside Handle
Pull Bar

Baggage Door Structure

Cam

Shim

SHOP NOTES:

3-14A

as a guide during removal, disassembly, assembly,

and installation. When installing an inside door
handle, locate it in the same relative position as
the opposite door handle.
3-18A. ADJUSTMENT OF DOOR LATCH - ALL
MODELS - 1966 AND ON. Adjustment of latch or
clutch cover is afforded by oversize and/or slotted
holes. This adjustment ensures sufficient gear-tobolt engagement and proper alignment.
NOTE
Lubricate door latch per Section 2. No lubrication is recommended for the rotary clutch.
3-18B. DOOR LOCK. Standard equipment on 100Series aircraft includes, in addition to interior
locks, a cylinder and key type lock on the left door.
If the lock is to be replaced, the new one may be
modified to accept the original key. This is desirable, as the same key is used for the ignition switch
and the cabin door lock. After removing the old
lock from the door, proceed as follows:
a. Remove lock cylinder from new housing.
b. Insert original key into new cylinder and file off
any protruding tumblers flush with cylinder. Without
removing key, check that cylinder rotates freely in
housing.
c. Install lock assembly in door, and check lock
operation with door open.
d. Destroy new key and disregard code number on
cylinder.
LTTER DOORS
319.
ANDBAGGAGE
3-19A. Beginning in 1967, a litter loading door may
be installed on the Models 180 and A185 as optional
equipment. When the baggage door and litter door
are opened, a single opening is available through the
side of the fuselage to permit loading of a stretcher
without removing the cabin door. When closed and
latched, the forward part of the litter door becomes
a structural member of the fuselage. The aircraft
should not be flown until the litter door and baggage
door are both closed and latched,
3-20. REMOVAL AND INSTALLATION. Baggage
door removal is accomplished by disconnecting the
door stop, then removing hinge pins or bolts securing door to hinges. The litter door may be removed
after the piano hinge pin has been removed.
3-21.

SEATS.

(See figures 3-6 thru 3-13.)

3-22. INDIVIDUAL SEATS. Standard individualseats
are equipped with manually operated reclining seat
backs. Rollers permit the seats to slide fore-andaft on seat rails, and pins which engage various holes
in seat rails lock seats in the selected positions.
Seat stops limit travel. Removal is accomplished
by removing the seat stops, and sliding the seats
forward and aft to disengage them from the seat
rails. Be sure to replace seat stops after installing
a seat.

WARNING
It is extremely important that the pilot's seat
stops are installed, since acceleration and
deceleration could possibly permit the seat
to become disengaged from the seat rails and
create a hazardous situation, especially during take-off and landing.
Vertically adjustable individual seats, operated
manually or by electrical power, may be installed in
all airplanes except the Model 150. The Model 150
standard seat does not slide fore-and-aft. Removal
is accomplished by unlatching the top of the seat back
and releasing the spring-loaded pins at the bottom of
the seat back. After removal of the seat back, the
seat bottom can be pivoted at the forward pins for
removal. The Model 150 optional reclining seat also
slides fore-and-aft. Removal is similar to the other
rail-mounted seats.
3-23. TWO-PLACE SEATS. Standard two-place
seats consist of a double-width seat bottom, and
either a double-width seat back or two single-width
seat backs. The single-width seat backs recline
separately. Removal is accomplished by removing
the bolts which secure the seat bottom to the fuselage. Use care not to damage upholstery when removing seats. If desired, seat backs may first be
removed from seat bottoms. Additional clearance
may be obtained by removing one or more arm rests.
NOTE
To help prevent upholstery damage, several
thicknesses of waxed heavy paper (waxed is
preferred) should be inserted between the seat
and the side panel and arm rest during removal
and installation of the seat.
3-24. STOWABLE SEATS. Stowable center and rear
seats may be installed as optional equipment in the
Model 180G and on, and in all Model 185 airplanes.
The center stowable seat (prior to 1967) is removed
by releasing the spring-loaded seat back catches and
removing the eyebolts attaching the seat bottom to the
fuselage. The rear stowable seat is removed by unsnapping the seat back and removing the seat bottom
pivot bolts. The seat bottom also may be pivoted upward and snapped to the rear wall. Except for minor
details, the rearmost stowable seat installation may
be used on all models as an auxiliary seat.
Beginning in 1967 the center seat on optional sixplace versions (Model 180 and 185) is divided into
two individual seats, each of which is equipped with
a removable seat back. Each seat is bolted to the
cabin structure with hand-removable eyebolts. The
seat is shown in figure 3-13.
3-25. POWER SEATS. Optional power seats for the
pilot and copilot may be installed in all airplanes
(prior to 1967) except the Model 150. An electric
motor, geared to a screwjack actuator, operates the
mechanism which raises and lowers the seat vertically. Fore-and-aft adjustment and seat back reclining adjustment are still accomplished manually.
3-15

The reclining mechanism is locked automatically in
any desired position throughout the travel range of
the seat back by releasing the reclining adjustment
handle. The seat is removed in the usual manner
after disconnecting electrical wires at the quickdisconnects in the floorboard, under the seat. When
installing a seat, either electrical wire may be attached to either quick-disconnect without affecting
seat operation. No limit switches are needed, as the
actuator "free-wheels" at each end of its travel.

3-26. REPAIR OF SEAT STRUCTURE. Replacement of defective parts is recommended in repair of
seats. However, a cracked seat framework may be
heliarc welded, provided the crack is not in an area
of stress concentration (close to a hinge or bearing
point). The square-tube aluminum framework used
on most seats is 6061 aluminum, heat-treated to a
T-6 condition. Torch welds are not feasible because
the excessive heat destroys the heat-treatment of the
frame structure. Figure 3-14 gives instructions for
replacing defective cams on reclining seat backs of
the type illustrated.
4

C/
1.
2.
3.
4.
5.
6.
7.

Right Seat Bottom
Seat Back
Seat Back Frame
Latch Arm
Release Handle
Pin
Left Seat Bottom

Figure 3-6. Standard Seats (Model 150)
3-16

NOTE
The baggage and cargo tie-downs
for the Model 150, illustrated in
figure 3-18, must be provided

when reclining seats are installed.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.

Seat Bottom
Seat Back
Seat Rail
Seat Stop
Cotter Pin
Clevis Pin
Screw
Nut
Cam
Spring
Cotter Pin
Clevis Pin

13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.

Shaft
Nut
Bolt
Roll Pin
Cotter Pin
Clevis Pin
Seat Adjustment Tube
Roller
Bushing
Bolt
Cotter Pin
Nut
Clevis Pin

Figure 3-7.

26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.

Seat Adjustment Pin
Spring
Seat Adjustment Clevis
Seat Adjustment Knob
Clip
Seat Spring
Seat Reclining Knob
Seat Reclining Tube
Nut
Bolt
Bolt
Nut

Reclining Seats (Model 150)
3-17

NOTE
Not all standard single seats are
equipped with handle stop (33).

~I rI

17 16

30
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Seat Bottom
Recline Handle
Pin
Shaft
Seat Back
Headrest
Ash Tray
Pocket
Nut
Washer
Bushing
Screw
Bushing
Spring

15.
16.
17.
18.
19.
20.
21.
22.

Screw
Pawl
Spring
Bolt
Bolt
Nut
Pin
Nut

23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.

Seat Roller Assembly
Bolt
Bracket
Washer
Pin
Spring
Pin
Pin
Fore-and-Aft Adjustment Handle
Seat Stop
Handle Stop
Clevis Bolt

Figure 3-8. Standard Single Seat
3-18

2. Channel
3. Torque Tube

5. Pin
6. Fore-and-Aft Adjustment Handle

Figure 3-9.

8. Vertical Adjustment Handle
9. Adjustment Screw

Vertically Adjustable Seat Mechanism
3-19

RECLINE STOP

RECLINE
ACTUATOR

MECHANISM

FORE -AND-AFT

ADJUSTMENT
HANDLE

-MOTOR AND
TRANSMISSION

Figure 3-9A. Power Seat
3-20

1. Seat Bottom
2. Safety Belt
3.
4.
5.
6.

Seat Back
Bolster Strip
Head Rest
Latch

7.
8.
9.
10.
11.
12.

Figure 3-10.

Seat Back Frame
Roll Pin

13.
14.

Spacer
Bolt

Spring
Bolt
Nut
Bolt

15.
16.
17.
18.

Support
Bolt
Screw
Upholstery Retainer

Two-Place Seat with Double-Width Back
3-21

NOTE
Not all seats of this type are
equipped with handle stops (14).
All 1968 models are equipped
with metal-to-metal seat belt

.9.

Recline Handle
10.

1.
2.
3.
4.

Seat Bottom
Bolt
Spring and Bushing
Bushing

5.
6.
7.
8.

Right Seat Back
Left Seat Back
Head Rest
Safety Belt

Figure 3-11. Two-Place Seat with Individual Backs
3-22

Pawl

11. Bolt
12. Washer
13. Control Shaft
14. Handle Stop
15. Clevis Bolt

1.
2.
3.
4.

15.

Headrest
Recline Pawl
Link

16.

10.

Figure 3-11A.
3-22A

Recline Shaft
Seat Bottom
Seat Back
Trim

Standard Two-Place Seat - 1968 Model 172

Knob

NOTE
The stowable seat installation shown here, except
for minor details, is used as an auxiliary seat in
all models. It is also used as the rearmost stowable seat in utility versions of all Model 185 airplanes and Model 180 airplanes beginning with the
Model 180G. The 1966 Model 150 auxiliary seat
bottom no longer folds up, and the seat back is
supported from the sides of the cabin.

1. Bottom Frame
2. Seat Bottom
3. Safety Belt

4. Seat Back
5. Latch Assembly
6. Left Floor Hinge
7. Spacer

Figure 3-12.

8. Right Floor Hinge
9. Strap
10. Support Bracket

Auxiliary Seat
3-23

'As

NOTE
See figure 3-17 for safety belts and cargo
tie-downs. The stowable seats shown here
are used in utility versions of all Model
185 airplanes and Model 180 airplanes beginning with the Model 180G.
CENTER SEATS
(1967 AND ON)
1.
2.
3.
4.
5.
6.

Screw
Clamp
Support
Center Seat Back
Rear Seat Bottom
Clip

7.
8.
9.
10.
11.
12.
13.

Washer
Nut
Rear Seat Back
Spacer
Hinge
Bolt
Handle

Figure 3-13. Stowable Seats
3-24

14.
15.
16.
17.
18.
19.

Cotter Pin
Spring
Center Seat Bottom
Eyebolt
Clevis Pin
Cable Yoke

BACK (REF)

CLEV BOLTSREF)SEAT
CLEVS BOLT (REF)
<

1.50" R. (CONSTANT AT EACH NOTCH)

REPLACEMENT CAM:
/
PAWL/ RF\>
\~^ ^ADJUSTABLE

PAWL (ICRE:-F)-<

\r\

/^\~

------

1414230-1 (SINGLE
SEAT)
1414230-2 (FULL
WIDTH REAR SEAT)

vjy______/

1414111-5 (VERTICALLY
ADJUSTABLE SEAT)

REPLACEIENT PROCEDURE:
a. Riov sen t from aircraft.
b. Remoe plastic upholstery panels from aft side loseat back, loosen upholstery retaining
rins and upholstery material as required to expose the rivets retaining the old cam assembly.
c. Drill out existing rivets and insert new cam assembly (2).
enggu first cam slot as shown.

Position seat back so that pawl (3)

d. Postion the cam so each lot bottom aligns with the 2.50" radius as shown.
e. Clamp securely in this position and check travel of cam. Pawl must contact bottom of each cam
slot. Using existing holes in seat frame, drill through new cam and secure with MS20470AD6
rivets.
f. Renstall upholstery, upholstery panels and seat.

Figure 3-14. Reclining Seat Cam Replacement
3-25

3-27. CABIN UPHOLSTERY.
3-28. Due to wide selection of fabrics and styles,
it is impossible to show each particular type of
upholstery. The following paragraphs describe
general procedures which will serve as a guide in
removal and replacement of upholstery. Major
work, if possible, should be done by an experienced
mechanic. If the work must be done by a mechanic
unfamiliar with upholstery practices, the mechanic
should make careful notes during the removal of each
item to facilitate its replacement later.
3-29. UPHOLSTERY MATERIALS AND TOOLS will
vary with the job. Scissors for trimming upholstery
to size and a dull-bladed putty knife for wedging the
material beneath the retainer strips are the only
tools required for most trim work. Use industrial
rubber cement to hold- oundproofing-mats-and-fabric
edges in place. Refer to Section 19 for thermoplastic repairs.
3-30. SOUNDPROOFING. The airplane is insulated
with spun glass mat-type insulation and a sound deadener compound applied to the inner surfaces of the
skin in most areas of the cabin and baggage compartment. Some airplanes utilize aluminum foil backed
tape to help reduce noise level in the cabin. All
soundproofing material should be replaced in its
original position any time it is removed. A soundproofing panel is placed in the gap between the wing
and fuselage and held in place by the wing root fairing. Cabin and baggage compartment upholstery and
carpeting also assist in reducing noise level.
3-31. CABIN HEADLINER REMOVAL,
a. Remove sun visors, all inside finish strips and
plates, door post upper shields, front spar trim
shield, dome light panel, and any other visible retainers securing the headliner.
b. Work edges of headliner free from metal tabs
which hold the fabric.
c. Starting at the front of the headliner, work the
headliner down, removing screws through metal tabs
which hold the wire bows to the cabin top. Pry loose
the outer ends of the bows from the retainers above
the doors. Detach each wire bow in succession.
NOTE
Always work from front to rear when removing the headliner; it is impossible to detach
the wire bows when working from rear to
front.
d. Remove the headliner assembly and bows from
the airplane.
NOTE
Due to the difference in length and contour of
the wire bows, each bow should be tagged to
assure proper location in the headliner.
e. Remove the spun glass soundproofing panels.

3-26

NOTE
The lightweight soundproofing panels are held
in place with industrial rubber cement.
3-32. CABIN HEADLINER INSTALLATION.
a. Before installing headliner, check all items concealed by the headliner to see that they are mounted
securely. Use wide cloth tape to secure loose wires
to the fuselage, and to seal any openings in the wing
roots. Straighten any tabs bent during removal of
the headliner.
b. Apply cement to inside of skin in areas where
soundproofing panels are not supported by wire bows,
and press soundproofing in place.
c. Insert wire bows into headliner seams, and secure rearmost edges of headliner after positioning
the two bows at the rear of the headliner. Stretch
-the material along the edges to make sure it is
properly centered but do not stretch it tight enough
to destroy the ceiling contours or distort the wire
bows. Secure the edges of the headliner with sharp
tabs, or, where necessary, rubber cement.
d. Work the headliner forward, installing each wire
bow in place with the tabs. Wedge the ends of wire
bows into the retainer strips. Stretch the headliner
just taut enough to avoid wrinkles and maintain a
smooth contour.
e. When all bows are in place and fabric edges
are secured, trim off any excess fabric and reinstall all items removed.
3-33. UPHOLSTERY SIDE PANELS. Removal of
upholstery side panels is accomplished by removing
seats for access, then removing parts attaching the
panels. Remove screws, retaining strips, arm
rests, and ash trays as required to free the various
panels. Automotive type spring clips attach most
door panels. A dull putty knife makes an excellent
tool for prying loose the clips. When installing upholstery side panels, do not over-tighten sheet metal
screws. Larger screws may be used in enlarged
holes as long as the area behind the hole is checked
for electrical wiring, fuel lines, and other components which might be damaged by using a longer screw.
3-34. WINDLACE (DOOR SEAL). To furnish an
ornamental edging for the door opening and to provide
additional sealing, a windlace is installed between the
upholstery panels or trim panels and the doorpost
structure. The windlace is held in place by sheet
metal screws.
3-35. CARPETING. Cabin area and bggage compartment carpeting is held in place by rubber cement,
sheet metal screws, or retaining strips. When fitting
a new carpet, use the old one as a pattern for trimming and marking screw holes. Utility airplanes use
a lightweight, heavy-duty vinyl floor covering instead
of carpeting.
3-36. BAGGAGE-COMPARTMENT UPHOLSTERY is
washable plastic held in place by screws and retainers. The floor covering is cemented to the floor in
some models. Cargo ie-downs and/or-safety belt
brackets may be removed as necessary where they
are installed through the floor covering.

TYPICAL EXCEPT MODEL 150

NOTE
These are typical headliner installations. There
are minor differences among the various models,
but maintenance procedures are similar. Soundproofing panels are used above the headliner on
most models.

MODEL 150D & ON

PRIOR TO MODEL 150D

Figure 3-15.

Cabin Headliner
3-27

3-37. SAFETY BELTS should be replaced if they
are frayed or cut, latches are defective, or stitching
is broken. Attaching parts should be replaced if excessively worn or defective. Some safety belts are
attached to the fuselage and others are attached to
the seats. Safety belt attachment fittings on some
models are also used as cargo tie-downs after unsnapping the quick-release type end fittings.
NOTE
When installing front seat safety belt fittings,
it is important that the correct attaching parts
be used. A large washer (AN970-3) or a plate
is used as a reinforcement under the floorboard at each front safety belt fitting. The
large washer is used between the forward nut
and the underside of the floorboard on the
Models 172, P172, 180, and 185. In addition,
the Models-172 andP172 use a plate-ty-pespacer
on top of the floorboard. Beginning with the
Model 172F, a reinforcing channel is riveted

under the floorboard, so that the large washer
and plate type spacer is not needed. The
Model 182 uses a reinforcing plate on the
underside of the floorboard, between nuts and
the floorboards.
3-38. CARGO TIE-DOWN PROVISIONS are used to
ensure that baggage cannot enter the seating area
during flight. The tie-down arrangements vary with
different aircraft and model year. Methods of attaching the tie-downs are shown in figure 3-16 through
3-18. The eyebolt and nutplate can be located at
various points, including cabin side walls, floor, and
aft baggage compartment wall. The sliding tie-down
lug also utilizes the eyebolt and attaches to a seat
rail. A baggage net is standard equipment on Models
172, P172, 182 and 150F and on. Tie-down straps
are standard equipment on the Models 150D and 150E.
Prior to the Model 150D, the tie-down straps are
optional-except-when-individual-reclining-seats are_
installed.

CARGO TIE-DOWN
LUG SLIDE ASSEMBLY

CARGO TIE-DOWN RING

'^^

Figure 3-16.

SHOP NOTES:

3-28

Cargo Tie-Down Rings

SEAT RAIL

BE SURE CENTER SEAT BELT BRACKET
IS IN LOCATION SHOWN. THE FLOORBOARD IS REINFORCED AT THE AFT HOLE
FOR STRUCTURAL REQUIREMENTS OF THE
SEAT BELT AND CARGO TIE-DOWN ATTACHMENTS.
NOTE

6
\rrcar

]

DAMAG

/oUP«UOT\

goKTnnc,
PA

NOTE

Carry-thru cable turnbuckle may be located
at either the right or left aileron bellcrank.
Direct cable turnbuckles are located at the
bellcranks prior to the 1801 and 185D, and
they are located at the control "U" on the
180H and 185D and on.
1.
2.
3.
4.

Aileron Bellcrank
Spacer
Turnbuckle Forks
Turnbuckle Barrels

i--7
CABLE TENSION:
40LBS *OLBS ON AILERON
CARRY-THRU CABLE (AT
THE AVERAGE TEMPERATURE
FOR THE AREA)

5. Right pirect Cable
6. Carry-Thru Cable
7. Cotter Pin
8. Pulley
9.

10. Bushing
11. Washer
12. Cable Guard
13. Left Direct Cable

Pulley

Figure 6-5. Aileron Control System-Models 180 & 185 (Sheet 1 of 2)
6-9

NOTE
Beginning in 1966, these
additional groups of pulleys
and spacers are used. Remainder of the cable routis unchaned.

CARRY-THRU CABLE
TO RIGHT-AILERON

-TO LEFT AILERON

....

Figure 6-5. Aileron Control System-Models 180 & 185 (Sheet 2 of 2)

SHOP NOTES:

6-10

....

FIGURE 6-8A

SEE FIGURE 6-2
NOTE

Carry-thru cable turnbuckle may
be located at either the right or

left aileron bellcrank.

CABLE TENSION:

40LBS *10LBS ON AILERON
CARRY-THRU CABLE (AT
THE AVERAGE TEMPERATURE
FOR THE AREA)

1. Turnbuckle Barrel
2. Carry-Thru Cable
3. Right Aileron Direct
Cable
4. Turnbuckle Fork
5. Nut
6. Washer

7.
8.
9.
10.
11.
12.

Bolt
Spacer
Cotter Pin
Pulley
Pulley
Pulley

13. Cable Guard
14. Left Aileron Direct
Cable
15. Pulley
16. Pulley
17. Spacer
18. Pulley

Figure 6-6. Aileron Control System-Model 150C (Sheet 1 of 2)

-Spacer

and washer

ALSO SEE
FIGURE 6-8A

6-12

Figure 8-6.

Aileron Control System - Model 150D & On (Sheet 2

NOTE

located
turnbuckle may be located
Carry-thru cable turnbuckle
left
bellcrank.
or
left aileron
aileron bellcrank.
the right
right or
at either the
SEFOR

1.
2.
2.
4.
3.
4.

Right Aileron Bellcrank
Turnbuckle
Direct
Carry-Thru
3. Cable
irect Cable
Cable Turnbuckle
Right
Turnbuckle
Cable
Carry-Thru
Right Direct Cable

Figure 6-6.
6-12

CABLE TENSION:

5.
5.
fie.
7.
8.
7.
8.
9.

FIGURE

Carry-Thru Cable
Pillley Bracket
Pulley
Spacer
Pulley
Spacer
Pulley
Cable Guard

40LBS ±10LBS
40LBS
+10LBS ON AILERON
AILERON
CABLE
CARRY-THRU
CARRY-THRU CABLE (AT
(AT
AVERAGE
THE
AVERAGE TEMPERATURE
THE
6-2A)

10. Left Direct Cable
11.
Direct
11.
and washer
SpacerTurnbuckle
Left Cable
12.
13.
12. Spaceri
Left Aileron Bellcrank
13. Spacer
14. Fairlead
Fairlead

Aileron Control System - Model 150D & On (Sheet 2 of 2)

ALSO SEE

SEE FIGURES
6-1 and 6-3-

PulleyJ

Carry-thru cable turnbuckle may be located at

40LBS

either the right or left aileron bellcrank. Direct
cable turnbuckles are located at the bellcranks
prior to the 172E, and they are located at the
control TT" on the
6172E
and on.

CARRY-THRU CABLE (AT
THE AVERAGE TEMPERATURE
FOR THE AREA)

1. Aileron Bellcrank

Right Aileron Direct

6.
7.
8.

Cotter Pin
Pulley
Bushing

C,.

Carry-Thru Cable
Turnbuckle
Carry-Thru Cable

Figure 6-7.

9.
11.
12.

LS ON AILERON

Washer
Left Aileron Direct
Cable
Direct Cable Turnbuckles

Aileron Control System - Model 172 & P172 Series

6-13
6-13

SEE FIGURE 6-4

4
NOTE

CABLE TENSION:

Carry-thru cable turn-

40LBS ±10LBS ON AILERON

buckle may be located
at either the right or
left aileron bellcrank.

CARRY-THRU CABLE (AT
THE AVERAGE TEMPERATURE
FOR THE AREA)

1. Cable Guard
2. Pulley
3. Nut
4. Washer
5. Bolt
6. Spacer
7. Pulley

8.
9.
10.
11.
12.
13.
14.
Figure 6-8.

6-14

Bushing
Rub Strip
Carry-Thru Cable
Left Aileron Direct Cable
Spacer
Aileron Bellcrank
Turnbuckle Fork

15. Turnbuckle
16. Bellcrank Stop Bushing
17. Pulley
18. Cotter Pin
19. Pulley
20. Right Aileron Direct Cable
21. Pulley

Aileron Control System -Model 182 Series

Figure 6-8A.

AILERON BELLCRANK
STOP BUSHING--

Aileron Cable Attachment

AILERON
DIRECT

AILERON BELLCRANK
STOP BUSHING

CABLE

AILERON

DIRECT
AILERON CARRY-

THRU CABLE

NOTE
Stop bushings should be centered in slots of
aileron bellcranks in each wing when control
wheels are neutral, with 40±10 pounds tension on aileron carry-thru cable. Push-pull
rods are then adjusted to rig the ailerons
neutral.
Figure 6-9. Rigging Aileron Bellcranks
6-15

2.2"-------UPPER CHAIN

ATURNBUCKLE

- TO SPROCKET ONLEFT CONTROL
COLUMN

AIRPLANE
(DIRECTLY ABOVE
IDLER SPROCKETS)

With pilot's control wheel neutral,
approximately 2. 2 assures that
correct link of chain is engaged with
sprocket on left control column.

VIEW LOOKING FORWARD
Figure 6-10.

8.
5.B e94.
7. Rib

6-16

Neutral Position for Rigging Control Column

Whr11

Lower Skin
Upper Inboard Skin

16. Check Nut

Figure 6-11. Typical Aileron Installation

17. Nut
18. Bracket
25.

Bolt

6-20. RIGGING - EXCEPT MODELS 180H, 185D,
172E AND ON AND 182L.
a. (See figure 6-1. ) On the control "T, " adjust the
total length of the spreader bar (5) and turnbuckle (6)
so that both control wheels are level in the neutral
position (synchronized).
b. (See figure 6-2. ) On the control "Y," adjust the
turnbuckles (11, 24, and 25) so that both control wheels
are level in the neutral position (synchronized) when
arm (18) is horizontal. Chain (12) should be engaged
so that there is an equal number of links extending
from sprocket (50).
c. (See figure 6-4. ) On the control column, check
that upper left chain (24) is engaged with left aileron
sprocket (22) in accordance with figure 6-10. With
pilot's control wheel in neutral position, adjust turnbuckles (25 and 32) so that both control wheels are
level in neutral position (synchronized).
NOTE
On aileron systems using the control "T,"
chain tension must be greater'than aileron
system tension to hold the adjustable end
fitting on the spreader bar (5, figure 6-1)
against its adjusting nut. However, too much
tension will cause binding. On the control
"Y," or control column, chains should have
the minimum amount of tension that will remove slack from the chains.
d. Tape a bar across both control wheels to hold
them in the neutral position.
e. (See figure 6-9.) Adjust the turnbuckles at the
aileron bellcranks so that the bellcrank stop bushings are centered in both bellcrank slots, with
40i10 pounds tension on the aileron carry-thru
cable. Disregard tension on direct cables, which
will be different than tension on carry-thru cable.
f. Adjust push-pull rod at each aileron 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 making this adjustment. Tighten
push-pull rod jamb nuts.
g. Safety all turnbuckles by the single-wrap
method using 0. 040-inch monel safety wire.
h. Remove bar from control wheels and install
all parts removed for access
i. Check ailerons for correct travel, using inclinometer shown in figure 6-12.
WARNING
Be sure that ailerons move in the correct
direction when operated by the control wheel.
6-21. RIGGING - MODELS 180H, 185D AND
172E AND ON.
a. (See figure 6-3. ) On the control "U, " check that
primary control cable is in aft groove of cable drum
and wrapped once around the drum and the controlometer
cable lock is installed at the bottom of the drum.
Note that transition cable lock is installed at the top.
b. With control wheels neutral, check that chain
ends are equidistant from sprockets.

c. Keeping control wheels neutral, tighten turnbuckles so that control wheels are level in the neutral position (synchronized), with enough tension
on cables to remove slack from chains, without
binding. Results of adjusting the turnbuckles are
as follows:
1. Loosening primary cable turnbuckles and
tightening secondary cable turnbuckle at center of
control "U"' will move the inboard sides of both control wheels down.
2. Tightening either primary control cable
turnbuckle and loosening secondary cable turnbuckle
at center of control "U" will move outboard side of
applicable control wheel down.
d. Tape a bar across both control wheels to hold
them in neutral position.
e. (See figure 6-9. ) Adjust the two aileron direct
cable turnbuckles below the control "U' and the
single carry-thru turnbuckle at the aileron bellcrank so that the bellcrank stop bushings are centered in both bellcrank slots with 40±10 pounds
tension on the aileron carry-thru cable. Disregard tension on direct cables, which will be different than tension on carry-thru cable.
f. Adjust push-pull rods at each aileron until the
ailerons are neutral with reference to the trailing
edge of the wing flaps. Be sure wing flaps are fully
up when making this adjustment.
g. Safety all turnbuckles by the single-wrap method
using 0. 040-inch monel safety wire.
h. Remove bar from control wheels and install all
parts removed for access.
i. Check ailerons for correct travel, using inclinometer shown in figure 6-12.

WARNI

WARNING

Be sure that ailerons move in the correct
direction when operated by the control wheel.
6-22.

RIGGING - MODEL 182L (See figure 6-4A.)

a. Relieve tension on system at turnbuckles.
b. Disconnect push-pull rods at bellcranks.
c. Adjust interconnect cables on cable drums to
position control wheels level (synchronized). While
maintaining neutral position of wheels, tighten interconnect cables until snug.
d. Block control wheels to hold neutral position.
e. Adjust the turnbuckles at the aileron bellcranks
as shown in figure 6-9 so the bellcrank stop bushings
WARNING
are centered in both bellcranks and to obtain specified
aileron carry-thru cable tension.
f. Adjust push-pull rod at each aileron to streamline ailerons with reference to flap trailing edge
(flaps full up), then secure push-pull rod jam nuts
and safety turnbuckles.
g. Remove bar from control wheels, then install
parts removed for access.
h. Check ailerons for correct travel using incli
hete aslerons for correc travel usine anshown in figure 6-12 of the Service Man-

WARNINGk
J
Be sure ailerons move in correct direction
when operated by control wheel.
6-17

AVAILABLE FROM CESSNA SERVICE PARTS CENTER (TOOL NO. SE 716)
Figure 6-12.

6-18

Inclinometer for Measuring Control Surface Travels

SECTION 7

WING FLAP CONTROL SYSTEMS

TABLE OF CONTENTS

Page

WING FLAP CONTROL SYSTEMS ......
Manual Wing Flap Operational Check ..
Trouble Shooting Wing Flap System Except Models 182, 172F & on,
and 150F & on ............
Flap Lever Assembly Removal, Repair,
and Installation. .
.........
Wing Flap Bellcrank Removal, Repair,
and Installation. ...........
Removal and Replacement of Cables
and Pulleys .............
Wing Flap Removal, Repair, and
Installation ...
Rigging Manual Wing Flap System

7-1
7-1
7-2
7-5
7-5
7-5
7-5

. . ..

7-5

Trouble Shooting Wing Flap System Models 182, 172F & on, and 150F & on .
Flap Position Transmitter Removal,
Installation, and Adjustment ......
Transmission and Motor Assembly Removal,
Repair, and Installation .
......
Drive Pulley Removal, Repair, and
Installation .............
Wing Flap Removal, Repair, and
Installation .............
Wing Flap Cables and Pulleys
Replacement .............
Rigging Electric Wing Flap System -

7-9
7-9
7-9
7-9
7-9

Model 182 Series (Prior to 1968) and

ELECTRIC WING FLAP CONTROL SYSTEM MODELS 182, 172F & on, and
150F & on ............
....

7-8

Model 172F and on .......
Rigging Electric Wing Flap System Model 150 ..
. ...
. ..
..

Electric Wing Flap Operational Check.

7-8

Flap Indicating System - Model 150.

7-8

7-9

7-9
7-14
. .

7-16

7-16
Rigging . ............
Rigging "Pre-Select" Wing Flap System . 7-16
.........
Model 182L .

7-1. WING FLAP CONTROL SYSTEMS.
7-2. The manually operated wing flap control systems
used on Models 180, 185, P172, and prior to Models
150F and 172F are illustrated in figures 7-2 through
7-4. The electrically operated wing flap control systems used on Models 182, 172F and on, and 150F and
on are shown in figure 7-5.
7-3. MANUAL WING FLAP OPERATIONAL CHECK.
a. Operate wing flaps through full range of travel,
observing for uneven or jumpy motion, binding and
lost motion in system. Make sure flaps are moving
together through full range of travel.
b. Retract wing flaps and check to see that they are

completely up.

Mount an inclinometer on one flap

and set to 0°.

NOTE
An inclinometer for measuring control surface travel is available from the Cessna
Service Parts Center. Refer to figure 6-12.
c. Extendwing flaps to full down position and check
for correct flap extended angle with inclinometer.
d. Remove wing flaps bellcrank access cover and
attempt to rock bellcrank to check for bearing play.
e. Inspect wing flap rollers and tracks for evidence
of defective parts.
7-1

7-4.

TROUBLE SHOOTING WING FLAP SYSTEM - EXCEPT MODELS 182, 172F & ON, AND 150F & ON.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

BOTH FLAPS FAIL TO LOWER WHEN LEVER IS RAISED.
Broken or detached forward
direct cable,

Open tunnel access cover aft of
lever and check direct cable.

Attach or replace cable.

Open bellcrank access cover and
feel for cable tension.

Attach or replace cable.

ONE FLAP FAILS TO LOWER.
Broken or detached direct
cable to malfunctioning flap.

BOTH FLAPS FAIL TO-RETRACT-WHEN-FLAP-LEVER-IS-LOWERED.
Broken or detached forward
return cable.

Open tunnel access forward of
lever and check forward return
cable.

Attach or replace cable.

BINDING IN SYSTEM AS FLAPS ARE RAISED OR LOWERED.
Cables not riding on pulleys.

Open access covers and observe
pulleys.

Route cables correctly over
pulleys.

Flap lever binding.

Check lever bearings and ratchet.

Replace defective parts.

Binding in flap bellcrank.

Check bellcrank in motion.

Replace defective bellcrank.

Remove bellcrank and check
needle bearings.

Replace or lubricate bearings.

Broken or binding pulleys.

Check pulleys for free rotation
or breaks.

Replace defective pulleys.

Frayed cable.

Check condition of cables.

Replace defective cables.

Flaps binding on tracks.

Observe flap tracks and rollers.

Replace defective parts.

INCORRECT FLAP TRAVEL.
Incorrect rigging.

Rig flaps correctly.

RELEASE BUTTON STICKS.
Release mechanism needs
lubricating.

7-2

Lubricate in accordance
with figure 2-4.

spacers (Si are

OUTBOhftD

3-0

'-'

d..

,.......

4. Cable Guard

7-4~7
CABLE TENSION:

30 LBS ± 10 LBS (AT THE
1.
3. Spacer
Pulley
AVERAGE
TEMPERATURE
FOR THE AREA).

.....

Flap Lever

11. Spacer

18.

8. Turubuckle
10.
Bushing

15.
17. Spacer
Latch Rod

8.
9.
10.
11.
12.

Turnbuckle
Snap Ring
Bushing
Spacer
Bushing

15. Spacer
16. Release Button
17. Latch Rod
18. Flap Lever
19. Spacer
20.

1.
2.
3.
4.
5.

Spacer
Bushing
Pulley
Cable Guard
Retract Cable

Bellcrank

13.

Flap Lever Ratchet

7. Direct Cable

14.

Latch

Push-Pull Rod

Figure 7-2. Wing Flap Control System - Except Models 150, 182, and 172F & on
7-4

NOTE
Paragraphs 7-5 through 7-8 are applicable to
manual wing flap control systems used in the
Models 172, P172, 180, and 185, illustrated
in figure 7-2. In the Model 150 manual flap
control system, routing and access to corponents are different, but similar maintenance may be accomplished while using figures
7-3 and 7-4 as guides.
7-5. FLAP LEVER ASSEMBLY REMOVAL, REPAIR
AND INSTALLATION. (See figures 7-2 thru 7-4. )
a. Remove front seats, tunnel carpeting, rear door
post facing, and access covers to gain access to flap
handle attachment.
b. Release cable tension on direct and retract
cables by loosening cable turnbuckles at rear door
post.
c. Disconnect forward direct and retract cables
from lever assembly by removing attaching bolt
and nut.
d. Remove flap lever pivot bolt and bushing, and
remove flap lever from tunnel structure.
NOTE
The spacer used to secure the flap lever
laterally has been replaced with a snap ring
which fits into a groove in pivot bolt bushing.
This configuration is also used for all spares.
e. Repair of wing flap lever assembly consists of
replacement of any defective bearings, spacers,
ratchet mechanism and other parts comprising the
assembly. Placards on the wing flap lever should
be replaced if they have become illegible.
f. Install wing flap lever assembly by reversing
the preceding steps and rigging the system as outlined in paragraph 7-9.
7-8. WING FLAP BELLCRANK REMOVAL, REPAIR
AND INSTALLATION. (See figures 7-2 thru 7-4.)
a. Remove access covers from wing lower skin at
the bellcrank.
b. Remove doorpost covering and release cable
tension by loosening cable turnbuckles.
c. Disconnect cables at bellcrank by removing
clevis bolts.
d. Disconnect wing flap push-pull rod at bellcrank.
e. Remove bellcrank pivot bolt from top of wing
and work bellcrank out through access opening, using
care that the bushing is not dropped. One or more
brass washers may be used as shims between wing
structure and bellcrank.
NOTE
Seal needle bearings with tape after bellcrank
is removed to prevent dirt from entering the
bearings.
f. Wing flap bellcrank repair is limited to replacement of internal bushings and bearings.
Cracked, bent or excessively worn bellcranks
should be replaced.

g. To install bellcrank, position bellcrank in wing
and install bolt through top of wing through bellcrank
pivot bushing. Secure bolt with washer and nut.
h. Attach cables with clevis bolts, nuts and cotter
pins.
i. Attach wing flap push-pull rod to bellcrank.
j. Rig wing flap system in accordance with paragraph 7-9.
7-7. REMOVAL AND REPLACEMENT OF CABLES
AND PULLEYS in the wing flap system may be accomplished using figures 7-2, 7-3 and 7-4 as a
guide.
7-8. WING FLAP REMOVAL, REPAIR AND INSTALLATION. (See figure 7-1.)
a. Extend wing flaps and remove access covers
from top leading edge of wing flap.
b. Disconnect push-pull rod at wing flap.
c. Remove bolt and nut at each aft flap track, then
pull flap aft and remove remaining nut and bolt. As
wing flap is removed from wing, all washers, rollers, and bushings will fall free, and they should be
retained for installation.
d. Wing flap repair may be accomplished in accordance with instructions contained in Section 19.
e. To install wing flap, position flap at trailing
edge of wing and install rollers and attaching parts
as illustrated in figure 7-1.
f. Set wing flap push-pull rods to 8-11/16" + 1/8"
between centers of rod end bearings and tighten rod
end jam nuts.
g. Attach wing flap push-pull rod to bracket on
flap.
h. Rig flap system in accordance with paragraph
7-9.
7-9.

RIGGING MANUAL WING FLAP SYSTEM.
NOTE

Before performing this procedure, release
wing flap cable tension at the turnbuckles.
a. Set wing flap push-pull rods to 8-11/16" ±1/8"
between centers of rod end bearings, tighten jam
nuts, and install.
b. Set wing flap control handle in the flap retracted position, then tighten retract cables to correct
tension.
c. Move wing flap control handle to the full down
position, then tighten direct cables to correct
tension.
d. Perform an operational checkout of the flap
control system, check all jam nuts for tightness,
check that all turnbuckles are safetied, and install
all parts removed for access.
NOTE
An inclinometer for measuring control surface travel is available from the Cessna
Service Parts Center. (See figure 6-12.)

7-5

130 LBS ± 10 LBS (AT THE

CABLE
10TEMPERATURE
LBS (AT THE
30 LBS ±TENSION:
AVERAGE
FOR THE AREA).

1.
2.
3.
4.
5.
6.

Pulley
Pulley Bracket
Right Direct Cable
Right Retract Cable
Left Retract Cable
Left Direct Cable

7.
8.
9.
10.
11.
12.
13.

Link
Bellcrank
Push-Pull Rod
Turnbuckle Barrel
Turnbuckle Eye
Forward Retract Cable
Forward Direct Cable

Figure 7-3. Wing Flap Control System-Model 150C
7-6

14.
15.
16.
17.
18.
19.

Latch
Collar
Release Button
Latch Rod
Flap Lever
Bushing

LOOKING FORWARD

-15

I
6

CABLE TENSION:
30 LBS 10 LBS (AT THE
AVERAGE TEMPERATURE
FOR THE AREA).

1.
2.
3.
4.
5.
6.

Pulley Bracket
Right Direct Cable
Right Retract Cable
Cable Guard
Flap Pulley
Left Retract Cable

7.
8.
9.
10.
11.
12.

Figure 7-4.

Link
Bellcrank
Left Direct Cable
Turnbuckle
Bulkhead
Bushing

13.
14.
15.
16.
17.
18.

Latch
Decal
Flap Lever
Latch Rod
Release Button
Spacer

Wing Flap Control System - MODELS 150D & 150E
7-7

7-10. ELECTRIC WING FLAP CONTROL SYSTEM MODELS 182, 172F & ON, and 150F & ON.
7-11. ELECTRIC WING FLAP OPERATIONAL
CHECK.
a. Operate wing flaps through full range of travel,
observing for uneven or jumpy motion, binding and
lost motion in system. Make sure flaps are moving
together through full range of travel
b. Deliberately overrun flap motor at each end of
stroke to make sure transmission is free wheeling.
c. Check to see that wing flaps are not sluggish in
operation. In flight at 100 mph, indicated airspeed,
the wing flaps should fully extend in approximately
9 seconds and retract in approximately 5 seconds.
On the ground with the engine running, the wing
_flapsshould extend or retract in approximately 6
seconds.
7-12.

d.
are
see
flap

Retract wing flaps and check to see that they
completely up. Check flap position indicator to
that it reads 0 ° . Mount an inclinometer on one
and set to 0°.
NOTE

An inclinometer for measuring control surface travel is available from the Cessna
Service Parts Center. Refer to figure 6-12.
e. Extend wing flaps to full down position and check
for correct flap extended angle with inclinometer.
f. Remove wing flap drive pulley access cover and
attempt to rock drive pulley to check for bearing play.
g. Inspect wing flap rollers and tracks for evidence
of-defective-parts.-

TROUBLE SHOOTING ELECTRIC WING FLAP SYSTEM - MODELS 182, 172F & ON, AND 150F & ON.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

BOTH FLAPS FAIL TO MOVE.
Popped circuit breaker or fuse.

Check circuit breaker or fuse.

Reset circuit breaker or replace fuse.

Defective switch.

Place jumper across switch.

Replace switch.

Defective motor.

Remove and bench test motor.

Replace motor.

Broken or disconnected wires.

Run continuity check of wiring.

Connect or repair wiring.

Defective or disconnected
transmission,

Check to see transmission is
Connect or replace
connected to flap system. If
transmission.
connected, remove for bench test.

Defective limit switch
(Model 182L).

Check continuity.

Replace switch.

Follow-up control disconnected
or slipping (Model 182L).

Check visually.

Secure control or
replace if defective.

BINDING IN SYSTEM AS FLAPS ARE RAISED AND LOWERED.
Cables not riding on pulleys.

Open access covers and observe
pulleys.

Route cables correctly over
pulleys.

Bind in drive pulleys.

Check drive pulleys in motion.

Replace drive pulley.

Broken or binding pulleys.

Check pulleys for free rotation
or breaks.

Replace defective pulleys.

Frayed cable.

Check condition of cables.

Replace defective cable.

Flaps binding on tracks.

Observe flap tracks and rollers.

Replace defective parts.

7-8

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

LEFT FLAP FAILS TO MOVE.
Disconnected or broken cable.

Check cable tensions.

Connect or replace cable.

Disconnected push-pull rod.

Check push-pull rod attachment.

Attach push-pull rod.

INCORRECT FLAP TRAVEL.
Incorrect rigging.

Rig flaps correctly.

Defective limit switch
(Model 182L).

Check continuity.

Replace switch.

Follow-up control disconnected
or slipping (Model 182L).

Check visually.

Secure control or
replace if defective.

SHOP NOTES:

7-8A

7-13. FLAP POSITION TRANSMITTER REMOVAL,
INSTALLATION, AND ADJUSTMENT. (See figure
7-5A.)
a. Remove access covers from bottom of right
wing below right drive pulley.
b. Remove cotter pin and pin which attach wire
rod (9) to arm (10) on right drive pulley.
c. Disconnect the transmitter electrical wires at
the quick-disconnects.
d. Remove two bolts which secure wing flap position transmitter to wing structure and remove transmitter from wing.
e. Installation of wing flap position transmitter
may be accomplished by reversing the preceding
steps.
f. After installation of wing flap position transmitter, adjust in accordance with step "o" of paragraph 7-18.
7-14. TRANSMISSION AND MOTOR ASSEMBLY
REMOVAL, REPAIR, AND INSTALLATION. (See
figure 7-5A.)
a. Transmission (3), motor (1), tube (4), and
hinge (2) are removed as one assembly if standard
fuel tanks are installed. With long range tanks installed, it is necessary to detach the assembly from
hinge (2) before removing motor and transmission
from wing and to attach them to the hinge after positioning them in the wing.
b. Remove access covers from bottom of right
wing under drive pulley and motor assembly.
c. Remove bolt securing tube (4) to right drive
pulley.
d. Remove bolt securing hinge (2) to the wing, or
If long range fuel tanks are installed, bolt
bolt
securing transmission to the hinge.
e. Disconnect electrical wires at quick-disconnects
and remove screw securing ground wire. Remove
assembly from the wing.
f. Repair of the transmission and motor assembly
consists of replacement of the motor (1), transmission (3), tube (4), or brake components. Bearings in hinge (2) may be replaced.
g. Installation may be accomplished by reversing
the preceding steps and rigging the flap control system in accordance with paragraph 7-18 or 7-19.

g. Remove drive pulley through access opening,
using care that the bushing is not dropped. One or
more brass washers may be used as shims between
wing structure and drive pulley.
NOTE
Protect drive pulley needle bearings from dust
or dirt by covering open ends with tape.
h. To remove the left wing drive pulley, use this
same procedure, omitting steps "c" and "d. "
i. Repair of drive pulleys is limited to replacement
of needle bearings. Cracked, bent, or excessively
worn drive pulleys should be replaced with a new
assembly.
j. Installation may be accomplished by reversing
the preceding steps and rigging as outlined in paragraph 7-18. Lubricate drive pulley bearings in accordance with Section 2 when installing drive pulley.
Control cables may be attached to drive pulleys before installing them in the wing.
NOTE
Transmitter arm (10) must be attached to
right drive pulley before installing the drive
pulley in the wing.
7-16. WING FLAP REMOVAL, REPAIR, AND INSTALLATION. The wing flap may be removed in
accordance with paragraph 7-8 and figure 7-1. If
flap push-pull rod adjustment is not disturbed, it
should not be necessary to rerig the wing flap systemove Check wing flap travel and rig if necessary
tem.
in accordance with paragraph 7-18. Repair of a
damaged wing flap may be accomplished in accordance with instructions contained in Section 19.
7-17. WING FLAP CABLES AND PULLEYS REPLACEMENT. Replacement of wing flap cables
and pulleys may be accomplished using figure 7-5
as a guide. Refer to paragraph 7-18 or 7-19 for
correct cable attachment.
NOTE

7-15. DRIVE PULLEY REMOVAL, REPAIR, AND
INSTALLATION. (See figure 7-5 or 7-5A.)

To ease rerouting of cables, a length of wire
may be attached to the end of the cable before
it is withdrawn from the aircraft. Leave the
wire in place, routed through the structure;
then attach it to the new cable and use it to
pull cable into place.

NOTE
The right drive pulley must be removed to
detach wing flap position transmitter arm
(10) from the drive pulley assembly.
a. Remove access covers under right drive pulley.
b. Remove bolt securing push-pull rod to drive
pulley and lower the flap.
c. Remove bolt securing tube (4) to right drive
pulley.
d. Remove pin to disconnect wing flap position
transmitter rod (9) from arm (10).
e. Loosen turnbuckles and tag and detach control
cables from drive pulley by removing bolts and pins.
f. Remove bolt, washer, and nut securing drive
pulley to wing.

7-18. RIGGING ELECTRIC WING FLAP SYSTEM MODEL 182 SERIES (Prior to 1968) AND MODEL
172F AND ON (See figure 7-5.)
NOTE
Before using this procedure, disconnect flap
cables at turnbuckles above cabin headliner,
disconnect flap push-pull rods at drive pulleys
in both wings, and disconnect tube (4) from
right drive pulley.
a.

If cables are not connected to left and right drive
7-9

MODEL 182

SEE FIGURE 7-6
FOR SCHEMATIC

MODEL 172 F AND ON

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

Pulley
Direct Cable
Retract Cable
Fairlead
Turnbuckle
Spacer
Bushing
Washer
Flap Position Indicator
Flap Switch

CABLE TENSION:
30 LBS * 10 LBS (AT THE
AVERAGE TEMPERATURE
FOR THE AREA).

Figure 7-5. Wing Flap Control System - Electric (Sheet 1 of 2)
7-10

MODEL 150F AND ON

SEE FIGURE 7-5A
FOR DETAILS

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Drive Pulley
Direct Cable'
Retract Cable
Turnbuckle
Flap Switch
Indicator Cover
Spacer
Support
Flexible Wire
Tubing
Clamp
Pointer
Spring
Spring Support

\-.\

NOTE
CABLE TENSION:
30 LBS * 10 LBS (AT THE
AVERAGE TEMPERATURE
FOR THE AREA).

The mechanical flap position
indicator is relocated to the
left door post for a vertical
presentation of indicated flap
movement on the Model 150H.
The sequence of components
remains the same.

Figure 7-5. Wing Flap Control System--Electric (Sheet 2 of 2)
7-11

NOTE

UP-LIMIT SWITCH

\
Items (8 thru 10) do not apply to the Model 150 electric
flap system. See Figure 7-5, Sheet 2, for mechanical
A relay, mounted in the right wing near the flap motor,
is incorporated in the electrical flap circuits of the Model
150, Serial No. 15062291 thru 15063135 and Model F150,
Serial No. F150-0001 thru F150-0034. A Service Kit
(SK150-16) is available from the Cessna Service Parts
Center to install the relay on earlier serials if desired.

-MODEL-150H

Beginning with-the Model 150, Serial No. 15063136; the
Model F150, Serial No. F150-0035; the Mode 172-SerialNo. 17254275; and the Model F127-0320 an improved flap
motor is used, and the relay is deleted.
The Model 150G and on uses a "slow-blow" fuse in the
flap circuit. When replacing, use only this type fuse.

Hinge Assembly

104.
Setscrew

.
Am4

Figure 7-5A. Wing Flap Motor, Transmission, and Linkage Details
7-12

CABLE

NOTE
of flap sys-

-Remainder-

tem is identical to
Model 182 system shown
on sheet 2 of figure 7-5.

1. Follow-up Control

:...7

APPLY GRADE 'C' LOCTITE

...

2. Travel Limit Switch

12.
13.

Flap Position Pointer
Bracket

UPON INSTALLATION-1

7-12A
7-1 2A

A^^-

*A~
~FLAP

MOTOR AND
TRANSMISSION

-W
FWD

DRIVE PULLEY

DRIVE PULLEY
SET SCREW

ACTUATING
TUBE
TURNBUCKLES-7

-;
RIGHT PUSHPULL ROD

LEFT PUSHPULL ROD
TO RIGHT

TO LEFT

WING

WING FLAP

VIEWED

FROM

FLAP

ABOVE

Figure 7-6. Wing Flap System Schematic - Models 182, 172F & on and 150F & on
pulleys, tube (4), left and right push-pull rods, and
the flap transmitter arm must be disconnected before
installing cables. If drive pulleys are not installed,
attach cables before installing drive pulleys in wings.
b. Connect the retract cable to the forward side
of the right flap drive pulley and to the aft side of the
left flap drive pulley.
c. Connect the direct cable to the aft side of the
right flap drive pulley and to the forward side of the
left flap drive pulley.
d. Connect flap position transmitter rod (9) to
right flap drive pulley arm (10).
e. Adjust both push-pull rods to 8-11/16 ± 1/8
inches between center of rod end bearings and tighten
lock nuts on both ends. Connect push-pull rods to
right and left flaps and drive pulleys.
NOTE
Temporarily connect the flap cables at turnbuckles above cabin headliner, and test flaps
by hand to see that flaps extend together. If
they will not, cables are incorrectly attached
to drive pulleys. Also see that right drive
pulley rotates clockwise, when viewed from
below, as flaps are extended. Disconnect
turnbuckles above cabin headliner again.
f. Using care not to cause damage, run flap motor to
fully retract actuating tube (4) on motor (full up position).
g. Loosen setscrew (11) and while manually holding
right flap full up, rotate nut and ball assembly (12)

in or out as required to align tube (4) with attaching
hole in drive pulley, tighten setscrew and attach tube
to drive pulley.
NOTE
Apply Loctite Sealant Grade C (American
Sealant Co., Hartford 11, Conn.) to threads
of setscrew (11) after final adjustments have
been made.
h. If tube (4) does not retract enough to connect to
the right drive pulley with flap full up, disconnect
push-pull rod at flap drive pulley and connect tube
(4) to flap drive pulley.
i. With flap motor full up, manually hold right
flap up and readjust push-pull rod to align with attaching hole in drive pulley. Connect push-pull rod
and tighten lock nuts.
NOTE
The right flap and motor must be correctly
rigged before the flap cables and left flap
can be rigged.
j. Operate flap motor to place right flap full up,
manually hold left flap full up and connect flap cables
at turnbuckles above headliner.
k. With flaps full up tighten flap cable turnbuckles
to obtain 30±10 pounds cable tension on each cable.
Adjust retract cable first.

7-13

NOTE
When tightening cable turnbuckles be sure the
cables are in the pulley grooves and cable ends
are correctly positioned at the drive pulleys.
Rig cable tension to the average temperature
for the area.
1. Disconnect push-pull rod at left drive pulley.
Run motor to extend flaps approximately 20 ° and
check tension on each flap cable. If necessary readjust turnbuckles to maintain 30*10 pounds cable
tension on each cable and safety turnbuckles.
m. Fully retract right flap. Manually holding left
flap up, readjust left push-pull rod to align with
attaching hole in left drive pulley and connect pushpull rod to drive pulley. Tighten locknuts.
n. With flaps up, mount an inclinometer on right
flap and set to 0° . Fully extend flaps and check flap
down angle. See Section 1 for wing flap travel for
appropriate airplane model. Repeat check on left
flap.
NOTE
Since flap rollers may not bottom in flap
tracks with flaps fully extended, some free
play may be noticed in this position.

locknuts on both ends. Connect push-pull rods to
flaps and drive pulleys.
NOTE
Temporarily connect the flap cables at turnbuckles above cabin headliner, and test flaps
by hand to see that flaps extend together. If
they will not, cables are incorrectly attached
to drive pulleys. Also see that right drive
pulley rotates clockwise, when viewed from
below, as flaps are extended. Disconnect turnbuckles above cabin headliner again.
d. Using care not to cause damage, run flap motor
to fully retract actuating tube (4) on motor (full up
position).
e. Loosen set-screw-(11-)-and-while-manually-hold-ing right flap full up, rotate nut and ball assembly
(12) in or out as required to align tube (4) with attaching hole in drive pulley, tighten setscrew, and attach
tube to drive pulley.
NOTE
Apply Loctite Sealant Grade C (American
Sealant Co., Hartford, 11, Conn.) to threads
of setscrew (11) after final adjustments have
been made.

o. Raise flaps to full up position and adjust flap
position transmitter to make indicator read 0° .
Slotted holes in the transmitter bracket are provided
for adjustment. If necessary, transmitter rod may
be formed slightly for additional adjustment.
p. Perform an operational checkout of the flap
control system, check all locknuts for tightness,
check that all turnbuckles are safetied, and install
all parts removed for access.

f. If tube (4) does not retract enough to connect to
the right drive pulley with flap full up, disconnect
push-pull rod at flap drive pulley and connect tube
(4) to flap drive pulley.
g. With flap motor full up, manually hold right flap
full up and readjust push-pull rod to align with attaching hole in drive pulley. Connect push-pull rod and
tighten locknuts.

NOTE

An inclinometer for measuring control surface travel is available from the Cessna
Service Parts Center. Refer to figure 6-12.

The right flap and motor must be correctly
rigged before the flap cables and left flap can
be rigged.

7-19. RIGGING ELECTRIC WING FLAP SYSTEM MODEL 150. (See figures 7-5 and 7-5A.)

h. Operate flap motor to place right flap full up,
manually hold left flap full up, and connect flap cables
at turnbuckles above headliner. Be sure direct cables
are connected to each other and return cables are
connected to each other.
i. With flaps full up, tighten flap cable turnbuckles
to obtain 30± 10 pounds cable tension on each cable.
Adjust retract cable first.

NOTE
Before using this procedure, disconnect flap
indicating system flexible wire from turnbuckle above cabin headliner, disconnect flap
cables at turnbuckles above cabin headliner,
disconnect flap push-pull rods at drive pulleys
in both wings, and disconnect tube (4) from
right flap drive pulley.
a. If cables are not connected to left and right drive
pulleys, tube (4) and the push-pull rods must be disconnected before installing cables. If drive pulleys
are not installed, attach cables before installing
drive pulleys in wings.
b. Connect cables as shown on Sheet 2 of figure
7-5.
c. Adjust both push-pull rods to 8-11/16+ 1/8
inches between center of rod end bearings and tighten
7-14

NOTE
When tightening cable turnbuckles, be surethe
cables are in the pulley grooves and cable ends
are correctly positioned at the drive pulleys.
Rig tension to the average temperature for the
area.
j. Disconnect push-pull rod at left drive pulley.
Run motor to extend-flaps approximately 20° and
check tension on each flap cable. If necessary, readjust turnbuckles to maintain 30 10 pounds cable
tension on each cable and safety the turnbuckles.

NOTE
The brake assembly is used on the Model 182 only
beginning with serial number 18255845. During the
1966 model-year an improved flap motor replaced
the existing motor, eliminating the need for the external brake. Alignment procedure still applies to
those aircraft equipped with the external brake.
Adjust brake assembly, with solenoid actuated, so
minimum clearance between brake lining and any
part of the coupling is . 001" and maximum is .010".
Do not bend spring (9).
*Alignment of flap motor shaft and transmission
shaft is important. After reassembly, coupling
assembly must turn freely. It is permissible to
enlarge the holes illustrated to a maximum of
.250" to obtain proper alignment.
1.
2.
3.
4.

Motor
Motor Shaft
Brake Drum
Setscrew

5.
6.
7.
8.

Coupling
Hinge
Transmission
Transmission Shaft

Figure 7-7.

9.
10.
11.
12.

Spring Assembly
Brake Lining
Solenoid
Bracket

Flap Motor Brake
7-15

k. Fully retract right flap. Manually holding left
flap up, readjust left push-pull rod to align with attaching hole in left drive pulley and connect pushpull rod to drive pulley. Tighten locknuts.
1. With flaps up, mount on inclinometer on right
flap and set to 0° . Fully extend flaps and check flap
down angle. Repeat check on left flap. On Model
150H, with flaps full up, adjust up-limit switch to
operate and shut-off motor at this position, then
mount an inclinometer on one flap, extend flaps and
check down angle. Repeat down angle check on
opposite flap. Check operation of up-limit switch
for positive shut-off through several cycles.
NOTE
Since flap rollers may not bottom in flap
tracks with flaps fully extended, some free
play may be noticed in this position.
m. Connect and rig flap indicating system (refer to
paragraph 7-20), then perform an operational checkout of the flap control system. Check all locknuts for
tightness, check that all turnbuckles are safetied,
and install all parts removed for access.
7-20. FLAP INDICATING SYSTEM (MODEL 150).
The mechanical indicating system consists of a tubing-enclosed flexible wire attached to the flap direct
cable at one end and to a pointer at the other end.
The pointer is attached to a return spring. Movement of the flap direct cable pulls the pointer along
a scale to indicate flap position as flaps are lowered.
Opposite movement of the flap direct cable permits
the return spring to pull the pointer in the opposite
direction as the flaps are raised. The system is
shown in figure 7-5, which may be used as a guide
for replacement of parts.
7-21. RIGGING OF FLAP INDICATING SYSTEM.
a. Operate flaps to full up position.
b. Open zipper in cabin headliner.
c. Loosen clamp securing flexible wire to flap
direct cable and adjust the wire as required to
place pointer at 00 (flaps up) position on indicator. Wrap flexible wire around clamp bolt as
shown in figure 7-5, then tighten clamp bolt.
d. Operate flaps to check that indicating system
functions properly.
e. Close zipper in cabin headliner.
7-22. RIGGING - "PRESELECT" WING FLAP
SYSTEM - MODEL 182L.
7-23. The three-position switch used prior to 1968
for flap actuation is replaced with a combination of
two microswitches mounted on a floating arm, and a
camming level. (See figure 7-5B.) These switches
actuate the system and control all mid-range settings.
Limit switches at the transmission deactuate the syster at either travel extreme. The transmission has
provisions for freewheeling at each end of travel. As
the flap control lever is moved to a desired setting,
its cam contacts a microswitch that actuates the motor. As the transmission moves, the follow-up control pulls control lever arm until it clears the microswitch, opening the circuit.
7-16

NOTE
Before using this procedure, disconnect flap
cables at turnbuckles above cabin headliner,
and disconnect flap push-pull rods at drive
pulleys and bellcranks in both wings.
a. If cables are not connected to drive pulleys, it
is necessary to disconnect parts attached to each
drive pulley so it may be rotated beyond its normal
range of travel to permit cable attachment. If drive
pulleys are not installed, attach cables before installing the drive pulleys in the wings.
b. The 3/32" retract cable connects to the forward
side of right drive pulley and to the aft side of the
left wing drive pulley. The 1/8" direct cable con-nects-to-the-forward-side of the left wing drive pulley
and the aft side of the right wing drive pulley.
c. Adjust both push-pull rods to 8-11/16 + 1/8
inches between center of rod end bearings and tighten
lock nuts on both ends. Connect push-pull rods to
right and left flaps and drive pulleys.
NOTE
Temporarily connect the flap cables at turnbuckles above cabin headliner, and test flaps
by hand to see that flaps extend together. If
they will not, cables are incorrectly attached
to drive pulleys. Also see that right drive
pulley rotates clockwise, when viewed from
below, as flaps are extended. Disconnect
turnbuckles above cabin headliner again.
d. Using care not to cause damage, run flap motor
to fully retract actuating tube on motor (full up position).
e. Loosen actuating tube setscrew and while manually holding right flap full up, rotate nut and ball
assembly in or out as required to align tube with
attaching hole in drive pulley, tighten setscrew and
attach tube to drive pulley.
NOTE
Apply Loctite Sealant Grade C (American
Sealant Co., Hartford 11, Conn. ) to threads
of setscrew after final adjustments have been
made.
f. If tube does not retract enough to connect to the
right drive pulley with flap full up, disconnect pushpull rod at flap drive pulley and connect tube to flap
drive pulley.
g. With flap motor full up, manually hold right flap
up and readjust push-pull rod to align with attaching
hole in drive pulley. Connect push-pull rod and
tighten lock nuts.
NOTE
The right flap and motor must be correctly
rigged before the flap cables and left flap
can be rigged.

h. Operate flap motor to place right flap full up,
manually hold left flap full up and connect flap cables
at turnbuckles above headliner.
i. With flaps full up tighten flap cable turnbuckles
to obtain 30*10 pounds cable tension on each cable.
Adjust retract cable first.
NOTE
When tightening cable turnbuckles be sure the
cables are in the pulley grooves and cable ends
are correctly positioned at the drive pulleys.
Rig cable tension to the average temperature
for the area.
j. Disconnect push-pull rod at left drive pulley.
Run motor to extend flaps approximately 20 ° and
check tension on each flap cable. If necessary readjust turnbuckles to maintain 30±10 pounds cable
tension on each cable and safety turnbuckles.
k. Fully retract right flap. Manually holding left
flap up, readjust left push-pull rod to align with
attaching hole in left drive pulley and connect pushpull rod to drive pulley. Tighten locknuts.
1. With flaps up, mount an inclinometer on right
flap and set to 0°.
NOTE
control
An for
inclinometer
measuring control surface travel is available from the Cessna
Service Parts Center. Refer to figure 6-12.
m. Fully extend flaps and check flap down angle per
Section 1, then repeat check on left flap.

n. Loosen follow-up control at switch mounting
arm (10).
o. Move control lever (8) to full UP position, then
without moving control lever, move arm (8) until
control lever cam (7) is centered between switches
(9) and (11). Secure follow-up control at this position.
p. Adjust switches (9) and (11) in sloted holes until
rollers just clear cam, then secure switches.
q. Turn on master switch and run flaps through
several cycles, stopping at various mid-range settings
and checking that cable tension is within limits. Retract cable tension may increase to 90 pounds when
flaps are fully retracted.
r. Run flaps to full UP position and mount an inclinometer on trailing edge of one flap, then set to 0°.
s. Run flaps to full down position and set downlimit switch to deactuate the system at this position.
NOTE
Since flap rollers may not bottom in flap
tracks with flaps fully extended, some free
play may be noticed in this position.
.

Flight test aircraft and check that follow-up condoes not cause automatic cycling, which indicates
the operating switches do not have sufficient clearance at the cam. If cycling occurs, readjust operating switches as necessary per step "p", then cornu. Check that all rod ends and clevis ends have
sufficient thread engagement, all jam nuts are tight,
then replace all parts removed for access.

NOTE
Since flap rollers may not bottom in flap
tracks with flaps fully extended, some free
play may be noticed in this position.

7-17

SECTION 8
ELEVATOR CONTROL SYSTEMS
Page

TABLE OF CONTENTS
ELEVATOR CONTROL SYSTEM .......
Trouble Shooting ............
REPLACEMENT OF COMPONENTS .....
Elevators ...............
Control Column .............

8-1.

8-1
8-1
8-8
8-8
8-8

ELEVATOR CONTROL SYSTEM.

8-2. The elevator control systems for the various
models are illustrated in figures 8-1 through 8-4.
The forward parts of the systems are operated by
four different control installations which are shown
8-3.

Rear Bellcrank - Models 180, 182and 185. .
Rear Bellcrank - Models 150, 172 and P172 .
Forward Bellcrank - Except Model 182 ..
Cables .................
.
RIGGING ................

8-8
8-8
8-8
8-8
8-8

in Section 6. On the Models 150, 172, and P172 the
elevator control cables are attached directly to a
bellcrank installed between the elevators, while on
the Models 180, 182, and 185 an additional bellcrank, push-pull tube, and an elevator down-spring
are installed in the system.

TROUBLE SHOOTING.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

NO RESPONSE TO CONTROL WHEEL FORE-AND-AFT MOVEMENT.
Forward or aft push-pull tube
disconnected.

Check visually.

Attach push-pull tube correctly.

Cables disconnected.

Check visually.

Attach cables correctly.

BINDING OR JUMPY MOTION FELT IN MOVEMENT OF ELEVATOR SYSTEM.
Defective forward bellcrank
pivot bearing,

Check bellcrank; move to check
for play or binding.

Replace bellcrank.

Defective rear bellcrank
pivot bearing,

Check bellcrank; move to check
for play or binding.

Replace bellcrank.

Cables slack.

Check for correct tension.

Adjust to correct tensions.

Cables not riding correctly on
pulleys.

Check cable routing.

Route cables correctly over pulleys.

Defective elevator hinges.

Move elevator by hand, checking
hinges.

Replace defective hinges.

Ball socket on instrument
panel too tight.

Disconnect universal joint
and check binding at panel

Add washers as necessary
between forward socket half
and instrument panel.

Clevis bolts too tight.

Check bolt binding.

Readjust to eliminate bolt
binding.

Defective control "T, " "Y,
or "U" pivot bearings.

Disconnect parts and check that
control pivots freely.

Replace defective bearings.

8-1

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

BINDING OR JUMPY MOTION FELT IN MOVEMENT OF ELEVATOR SYSTEM (Cont).
Defective control column
needle bearing rollers.

Check visually.

Replace defective rollers.

Defective control column
torque tube bearings.

Disconnect parts and check that
torque tube rotates freely.

Replace defective bearings.

Glide on aft end of control
square tube adjusted too tightly.

Remove control wheel and check
glide for binding,

Loosen screw and tapered plug
in end of glide enough to eliminate binding.
Lubricate in accordance with
figure 2-4

Lubrication-needed.
Defective pulleys or cable
guards,

Check manually.

Replace defective parts and
install guards properly.

ELEVATOR FAILS TO ATTAIN PRESCRIBED TRAVEL.
Stops incorrectly set.

Rig per paragraph 8-11.

Cables unevenly tightened.

Rig per paragraph 8-11.

Interference at firewall or
instruments.

Check visually.

Rig per paragraph 8-11.

Forward bellcrank stop
bolt (Models 180 and 185)
adjusted incorrectly.

With rear bellcrank against
elevator up stop, check for 1/8
inch clearance at forward bellcrank up stop.

Adjust per paragraph 8-11.

SHOP NOTES:

8-2

.SEE FIGURE 6-2

"-.. A . .. ...

e'..
1.

,-,

\;-'.,\----:uo---°°

*,- ' //.
""--."?,"/

./.\

.o-/, .

CABLE TENSION:

30 LBS i 10 LBS (AT THE
AVERAGE TEMPERATURE
THE
i AREA).1.

ElevaorTraveFOR

Pulley9.

4 Bo '"'12

15. 13
Cabl

Washer

13 I5~
13

Nut .

12 --.
2,

5.
6.
7.
8.

Up Cable
Bolt
Elevator Bellcrank
Down Cable

13.
14.
15.
16.

Bolt
Clevis Bolt
Nut
Cotter Pin

21.
22.
23.
24.

Nut
Push-Pull Tube
Bolt
Bolt

Figure 8-1. Elevator Conrol System-Model 150
8-3
8-3

APPLICABLE TO
MODELS P172 AND
PRIOR TO 172F

CA\

ii
Nut

l41

17i
|

. Bolt
SEE

*'*

8-/4 P /\
20

Nut

2.
3.
4.
5.
6.
7.

Pulleys
Bolt
Washer
Bolt
Cotter Pin
Clevis Bolt

l///
eo

.-^1

Make no attempt to

Clean new contacts with

clear, unleaded gasoline before installing.

4. Check cam follower oiling felt. If it appears
dry, re-oil with 2 or 3 drops of lubricant (Scintilla
10-86527, or equivalent). Allow about 30 minutes
for the felt to absorb the oil, then blot off excess
12-31

with a clean cloth. Too much oil may result in fouling and excessive burning of contacts.
5. Check that the condenser mounting bracket
19 not cracked or loose. If equipment is available,
heck condenser for a minimum capacitance of .30
:.- ufarads. If equipment for testing is not availii;:e and a defective condenser is suspected, replace
wth a new one.

c. If the trouble has not been corrected after
accomplishing steps "a" and "b," check magnetoto-engine timing. If timing is not within prescribed
tolerance, remove magneto and set internal timing,
then reinstall and time to the engine.
d. If the trouble has still not been corrected, magneto overhaul or replacement is indicated.

UPPER
SPARK PLUGS
=-__
---

-LOWER-

SPARK PLUGS

.- II

LEFT
MAGNETO

RIGHT
MAGNETO

FIRING ORDER 1-3-2-4

Figure 12-9. Model 150 Ignition Schematic
12-32

-------^

LEFT

FIRIN

ORDER 1-6-3-2-5-4

SPARK PLUGS

RIGHT

Figure 12-10. Model 172 Ignition Schematic
12-33

Figure 12-11.
12-34

Model P172 Ignition Schematic

Figure 12-12. Models 180, 182, and 185 Ignition Schematic
12-35
12-35

'-11.4
TYPICAL FOR

ALL MODELS
i--

..'

/ -_- -

.T¢2)Screw clevises onto controls so that conis visible through inspection bole (15).
-trol

NOTE
Minor changes in the clamping
and routing are the differences
in the various models,

-Position

MODELS 180 & 185

controls in clamps so cowl flaps
are closed snugly. When cowl flaps are
lowered, they should be open 16' (+2° -1').

MODEL P172
,)Set control in full closed position.

2 Screw clevises onto controls so that control is visible through inspection hole (15).

Position controls in clamps so cowl flaps
are open 2"+.00"-.25" measured at outboard corners (control closed). When
cowl flaps are lowered, they should be
open 6"+.00"-.25".

FROM
ENGINE MOUNT

Figure 12-13.
12-36

1.
2.
3.
4.
5.
6.
7.
8.

Bracket
Clamp
Bolt
Control
Washer
Nut
Control Clevis
Spacer

Cowl Flaps Rigging (Sheet 1 of 2)

9.
10.
11.
12.
13.
14.
15.
16.

Lever
Plate
Screw
Knob
Cotter Pin
Clevis Pin
Inspection Hole
Rod End Clevis

MODEL 182

g -'

8.
9.
10.

Spacer
Screw
Screw

'is

14.
15.
16.

Figure 12-13.

Support Bracket
Clamp
Bolt

20.
21.
22.

Clevis Pin
Inspection Hole
Shock Mount

Cowl Flaps Rigging (Sheet 2 of 2)
12-37

MOUNT-TO-FIREWALL
MODEL 180F PRIOR TO
SERIAL 18051251

MOUNT-TO- FIREWALL
MODEL 180F SERIAL
18051251 THRU 18051312

MOUNT-TO-FIREWALL
MODEL 182

MOUNT-TO-FIREWALL
MODEL 180G AND ON

MOUNT-TO-FIREWALL

MOUNT-TO-FIREWALL
MODEL P17REWALL

MOUNT-TO-FIREWALL
TOP CENTER ONLY
MODEL 150

Figure 12-14. Engine Mount Details (Sheet 1 of 2)
12-38

UPPER MOUNT-TOFIREWALL MODEL 185

1
LOWER MOUNT-TOFIREWALL MODEL 185

12 78

ENGINE COWLING.

12-79. REMOVAL AND REPLACEMENT of engine
cowling is accomplished by removing attachingscrews
and bolts, and releasing quick-release fasteners.
On models with cowl flaps, it is necessary to lower
the cowl flaps and disconnect each one from its control or linkage. Various changes have been made in
design of air inlets, air filters, ducting, and flexible
connections. Disconnect any of these which interferes
with removal of the cowling. When replacing the
cowling, be sure to connect any items disconnected
during removal If cowl flap adjustment was disturbed, rig per figure 12-13.
12-80. CLEANING. Wipe the inner surfaces of the
cowl with a cloth saturated with cleaning solvent. If
-the inside ofthe cowl is coated heavily with grease
and dirt, allow the solvent to soak until-the-foreign
material can be removed. Painted surfaces should
be cleaned by washing with water and a mild soap.
Waxing after cleaning is recommended to prolong
paint life.
12-81. REPAIR of engine cowling is outlined in
Section 19.
12-81A. ENGINE COWLING (SHOCK-MOUNTED).
The engine cowling on the 1967 Model 172 and Model
150 is similar to the cowling formerly used, except
that it is shock mounted. Instead of attaching directly to the fuselage, the cowling attaches to shock
mounts which, in turn, are fastened to the fuselage.
Quick-release fasteners are used at the cowling-toshock mount attach points to facilitate removal of the
cowling.
NOTE
When new shock mounts or brackets are being
installed, careful measurements should be
made to position these parts correctly on the
firewall. These service parts are not predrilled. Install shock mounts on brackets so
that cowling and shock mount are correctly
aligned. Sheet aluminum may be used as
shims between bracket halves to provide
proper cowling contour.
12-82.

BAFFLES.

12-83. Engine baffles are constructed of metal and
strips of asbestos fabric. They are designed to direct ram air around the cylinders and engine components in a manner that will provide optimum cooling of the engine. An additional baffle has been
added to the No. 5 cylinder head on the Model 185,
beginning with Serial No. 185-0745. As instructed
in Service Letter 64-32, this baffle should be added
to all earlier Model 185 airplanes.
12-84. REMOVAL AND REPLACEMENT of the various baffle segments is possible with the cowling removed. Be sure that any replaced baffles seal properly.

\,-40

12-85. REPAIR of engine baffles is outlined in Section 19.
12-86.

ENGINE MOUNT (TUBULAR).

12-87. The engine mount is composed of sections of
tubing welded together and reinforced with welded
gussets. The purpose of the mount is to support the
engine and attach it to the airframe. The engine is
attached to the engine mount with shock-mount assemblies which absorb engine vibrations. On some
models, the engine mount is also shock-mounted to
the fuselage.
NOTE
On the Model 150, the engine mount supports
the nosewheel shock strut. Included in the
-Model-P172-engine-mount-to-fuselage attachments are shock mounts which support the
free floating engine cowling.
12-88. REPLACEMENT of the engine mount necessitates removal of the engine, followed by removal
of the bolts attaching the mount to the fuselage.
NOTE
When tightening engine mount bolts, two different procedures should be used. If the bolt
secures metal parts together or tightens against a metal spacer, the standard torque
values listed in Section 1 should be used. If
the bolt compresses rubber pads with no
metal spacer in between, tighten until the
rubber pads bulge out slightly, but do not
tighten enough to cause damage to the rubber.
A new engine mount and doublers added to the firewall at the four outboard mount attach points are installed on the Model 150, beginning with Serial Number
15061640. As a result of the doublers being installed,
the outboard attach legs of the engine mount have been
shortened .06 inch. The new engine mount supersedes
the engine mount used on'the earlier Model 150 as a
replacement mount.
NOTE
When installing this new mount or. the Model
150 prior to 15061640 (except those modified
per Service Kit Number SK150-14), one additional AN970-5 washer must be installed under
each of the outboard mount legs to compensate
for the .06 inch shortening of the mount legs.
12-89. REPAIR of the engine mount should be performed carefully as outlined in Section 19. The
mount should be painted with heat-resistant black
enamel after welding or whenever the original finish has been removed.
During the 1968 model year, the paint finish on the
Model 180, 182, and 185 engine mounts is changed to
provide greater protection against corrosion. This

paint C-I High (Chemical Industrial Co., Brooklyn,
Ohio) is available from the Cessna Service Parts
Center. The mount should be painted after welding
or whenever the original finish has been removed.
To paint engine mounts that are painted with heatresistant black enamel and metalized:
a. Remove old finish and any evidence of corrosion.
b. Prime the affected area with synthetic red primer. Allow primer to dry a minimum of two hours.
c. Apply heat-resistant back enamel. Apply by
spray if possible, if not finish may be applied with a

brush.
d. If metalized area is affected, remove corrosion
as completely as possible and paint metalized area
with C -I High. Do not use a primer under this paint.
Paint may be used with spray gun or brush.
e. If refinishing the entire mount is feasible,
finish with C-I High paint. Do not use a primer beneath this material.
f. If the engine mount is finished with the C-I High
material and refinish is required, remove corrosion
and apply finish.

,-:MODEL

. ..

172H

MODEL 150G

1.
2.

Engine Cowling
Quick-Release Fastener

Figure 12-14A.

3.
4.
5.

Fuselage
Asbestos Seal
Shock Mount

6.
7.

Bracket
Firewall

Engine Cowling Shock Mounts
12-41

OIL SYSTEM.
12-91. Wet sump, pressure-lubricating oil systems
a'e employed in the engines of all the aircraft covered
", thiq manual. In these engines, oil under pressure
ir )m the oil pump is fed through drilled crankcase
passages which supply oil to the crankshaft main
Iearings and camshaft bearings. Connecting rod
bearings are pressure lubricated through internal
passages in the crankshaft. Valve mechanisms are
tuorncted through the hollow push-rods, which are
upoplied with oil from the crankcase oil passages.
Oil is returned by gravity to the engine oil sump.
12-92.

Cylinder walls and piston pins are spray-lubricated
by oil escaping from connecting rod bearings. Noncongealing and large oil coolers may be installed on
some models. The non-congealing oil cooler prevents the oil from congealing when operating in low
temperatures by means of warm-up passages through
which engine oil is permitted to circulate continuously. Oil coolers are controlled by a thermostat. A
pressure relief valve maintains proper engine oil
pressure. Removable oil filter screens are provided in the engine oil system and external, replaceable-element filters are optional equipment on most
models.

TROUBLE SHOOTING.

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

NO OIL PRESSURE.
No oil in sump.

Check with dipstick.

Fill sump with proper grade and
amount of oil.

Oil pressure line broken, disconnected, or pinched.

Inspect oil pressure line.

Replace or connect.

Oil pump defective.

Remove and inspect.

Examine engine. Metal particles
from damaged pump may have entered engine oil passages.

Defective oil pressure gage.

Check with another gage. If second reading is normal, airplane
gage is defective.

Replace gage.

Oil congealed in gage
line.

Disconnect line at engine and
gage; flush with kerosene.

Pre-fill with kerosene and
install.

Relief valve defective.

Remove and check for dirty or
defective parts.

Clean and reinstall; replace
If defective.

LOW OIL PRESSURE.
Low viscosity oil.

Drain oil and refill sump with
proper grade of oil.

Low oil level.

Check with dipstick.

Fill sump to proper level with
proper grade of oil.

Oil pressure relief valve
spring weak or broken.

Remove and check spring.

Replace weak or broken spring.

Defective oil pump.

Check oil temperature and oil
level. If temperature is higher
than normal and oil level is correct, internal failure is evident.

Examine engine. Metal particles
from damaged oil pump may have
entered engine oil passages.

Secondary result of high oil
temperature.

Observe oil temperature gage for
high indication,

Determine and correct reason
for high oil temperature.

12-42

PROBABLE CAUSE

REMEDY

ISOLATION PROCEDURE

HIGH OIL PRESSURE.
Drain oil and refill sump with
proper grade and amount of oil.

High viscosity oil.

Relief valve defective.

Remove and check for dirty or
defective parts.

Clean and reinstall; replace if
defective.

Defective oil pressure gage.

Check oil pressure with another
gage. If second gage gives a normal reading, airplane gage is defective.

Replace oil pressure gage.

Oil cooler thermostat defective.

Feel front of cooler core with
hand. If core is cold, oil is bypassing cooler.

Replace thermostat.

Oil cooler air passages clogged.

Inspect cooler core.

Clean air passages.

Oil cooler oil passages clogged.

Attempt to drain cooler. Inspect
any drainings for sediment.

Clean oil passages.

Oil congealed in oil cooler.

This condition can only occur
in extremely cold temperatures.

If congealing is suspected,
use external heater or a heated
hangar to thaw the congealed
oil.

Secondary effect of low oil
pressure.

Observe oil pressure gage for
low indication.

Determine and correct reason for
low oil pressure.

Defective oil temperature gage.

Check with another gage. If second reading is normal, airplane
gage is defective.

Replace gage.

Defective oil temperature bulb.

Check for correct oil pressure,
oil level and cylinder head temperature. If they are correct,
check oil temperature gage for
being defective; if a similar reading is observed, bulb is defective.

Replace temperature bulb.

Defective oil temperature bulb
or gage.

Check with another gage. If reading is normal, airplane gage is
defective. If reading is similar,
temperature bulb is defective,

Replace defective part.

Oil cooler thermostat defective
or stuck closed.

Remove valve and check for
proper operation.

Replace thermostat.

HIGH OIL TEMPERATURE.

LOW OIL TEMPERATURE.

12-43

1293.

FULL-FLOW OIL FILTER.

gaskets may cause false torque readings, a-

12-94. Three configurations of optional external fullflow oil filters have been installed on some of these
airplanes. The filter and filter adapter replace the
regular engine oil filter screen. The earlier configuration, illustrated in figure 12-15, incorporates
only a bypass valve inthe filter adapter. In a later
configuration, illustrated in figure 12-15A, the filter
adapter incorporates a bypass valve, outlet valve,
and isolation valve. Normally, oil from the engine
oil pump flows through the isolation valve, through
the filter element, through the outlet valve to the
engine oil passages. If the filter element should become blocked, the bypass valve will open, allowing
oil-to-flow-to-the-engine-oil-passages.-The isolation
valve blocks off the filter assembly, and oil then
flows through the bypass valve, if excessive oil
pressure should occur. In the other configuration,
the shorter filter can, shown in figure 12-15A, maybe
used with the earlier filter adapter. Replacement
filter adapters are of the latest type as shown in figure 12-15A. Beginning with the 1967 Models 180,
185, and 182, a similar adapter that does not contain
the outlet and isolation valves is used. This new
adapter is also used for all service parts, except on
the Models 150 and 172 which continue to use both
valves.
12-95. FILTER ELEMENT REPLACEMENT.
figures 12-15 and 12-15A.)

(See

NOTE
Filter element replacement kits are available
from the Cessna Service Parts Center.
a. Remove engine cowling as necessary for access.
b. Remove both safety wires from filter can and unscrew hollow stud (1) to detach filter assembly from
adapter (10) as a unit. Remove from the airplane,
discarding gasket (9).
c. Press downward on stud (1) to remove.
d. Lift lid (7) off filter can, discarding gasket (6).
e. Pull filter element out of can and discard.
f. Wipe parts clean with a soft cloth.
NOTE
When installing a new filter element, it is important that all gaskets are clean, lubricated,
and positioned properly, and that the correct
amount of torque is applied to filter attaching
stud. If the stud is under-torqued, oil leakage will occur. If the stud is over-torqued,
filter can may be deformed, again causing
oil leakage.
Lubricate rubber grommets in new filter
element, rubber gaskets (9) and (6), and
metal gasket (2) with clean engine oil or general purpose grease before installation. Dry

12-44

gain resulting in oil leakage.
Before assembly, place a straightedge across
bottom of filter can. Check for a distortion or
out-of-flat condition greater than .010 inch.
Replace if either of these conditions exist.
Before assembly, cut adapter nut safety wire
and try to rotate adapter by hand. If adapter
can be moved, check for thread deformation
in engine and adapter.
After installing a new gasket on lid (7), turn
it upside down. If gasket falls, replace gasket and repeat test. If this gasket falls off,
replace lid.
g. Inspect adapter gasket seat for gouges, deep
scratches, wrench marks, and mutilation. If any
of these are found, replace adapter.
h. Place new element in can, and insert stud (1)
with new metal gasket (2) in place, through the can
and element.
i. Position new gasket (6) inside lower flange of
lid (7). Position new gasket (9) around upper flange
of lid (7). Place the lid in position.
j. Install filter assembly on adapter. Holding can
to prevent it from turning, tighten stud (1) and torque
to 20-25 lb-ft, using a torque wrench.
k. Reinstall parts removed for access, and service
the engine with proper grade and quantity of oil. One
additional quart of oil is required each time the element is replaced.
1. Start engine and check for proper oil pressure.
Check for leaks after warming up engine.
m. Again check for leaks after engine has been run
at a high power setting (preferably a flight around
the field).
n. Check to make sure filter has not been making
contact with adjacent parts due to engine torque.
o. While engine is still warm, recheck torque on
stud (1), then safety stud to lower bracket (3) on
filter can, and safety adapter to upper bracket (3)
on filter can.
12-96. FILTER ADAPTER REMOVAL. (See figures
12-15 and 12-15A. )
a. Remove filter assembly as outlined during
element replacement.
b. Note angular position of adapter, then remove
safety wire and loosen adapter nut (11).
c. Unscrew adapter and remove from engine.
NOTE
A special wrench adapter for adapter nut (11)
Part No. SE-709, is available from the Cessna
Service Parts Center, or one may be made as
shown in figure 12-16.

Do NOT substitute automotive gaskets
for any gaskets used in this assembly.
Use only approved gaskets listed in the

Spring (19) used on earlier
filters only.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.

Stud
Metal Gasket
Safety Wire Tab
Can
Filter Element
Lower Gasket
Lid
Nut
Upper Gasket
Adapter
Adapter Nut
O-Ring
Snap Ring
Retaining Cap
Spring
Ball
Plug
Thread Insert
Spring

.
Figure 12-15.

Full-Flow Oil Filter
12-45

NOTE
Do NOT substitute automotive gaskets for any gaskets
used in this assembly. Use only approved gaskets
listed in the Parts Catalogs.
Beginning with the 1967 Models 180, A185, and 182, a
similar adapter that does not contain outlet valve (13)
or isolation valve (15 thru 21) is used. This newer
adapter is also used for all service parts, except on
the Models 150 and 172. These models still use the
adapter containing the isolation valve (15 thru 21) and
outlet valve (13). Plug (21) is replaced with a plug
containing tapered threads on later adapters, and the
tightening
-dimensions-shown-apply-only-to-straightthreads.

13
14

,
11

(

ISOLATION
VALVE

NUT DELETED ON CURRENT
INSTALLATIONS (DISCARD AT
NEXT FILTER ELEMENT
CHANGE)-

2 i1

21
21

Stud

2.
3.
4.
5.
6.
7.
8.
9.
10.
11.

Metal Gasket
Safety Wire Tab
Can(.
Filter Element
Lower Gasket
Lid
Nut
Upper Gasket
Adapter
Adapter Nut

12.

O-Ring

13.
14.
15.
16.
17.
18.
19.
20.
21.
22.

Outlet Valve
Bypass Valve
Countersunk Washer
Sleeve
O-Ring-Piston
O-Ring
Spring
Plug
Thread Insert

40"
00

S
~
SPOTFACE
4

NOTE
"

When installing plug (21), tighten
to dimension shown.

3
2

Figure 12-15A.
12-46

03")

Full-Flow Oil Filter

12-96A. DISASSEMBLY, REPAIR, AND ASSEMBLY
OF FILTER ADAPTER. Figure 12-15 shows the relative position of internal parts of the earlier filter
adapter and may be used as a guide during replacement of parts. Figure 12-15A shows the relative
position of internal parts of later filter adapters and
may be used as a guide during replacement of parts.
The bypass and outlet valves are to be replaced as
units, with the bypass valve being staked three places
at installation. The detail parts which form the isolation valve may be replaced individually. Also use
new seals, lubricate parts with engine oil, and replace any parts that shows signs of excessive wear.
Note that washer (15) is installed with its countersunk side toward outlet valve (13). Tighten plug (21)
to a maximum of .40 inch as shown in figure 12-15A.
The hell-coil type insert (22) in the adapter may be
replaced, although special tools are required. Follow
instructions of the tool manufacturer for their use.
Since the isolation valve is not used in later adapters
on the Models 180, 185, and 182, the isolation valve
may be removed, if desired. To remove the isolation
valve, remove plug (21) and parts (15 thru 20). Weld
shut vent hole in plug (21). Reinstall washer (15),
sleeve (16), O-ring (17), and plug (21) in the adapter.

12-97. FILTER ADAPTER INSTALLATION.
a. Assemble adapter nut and new O-ring on adapter
in sequence illustrated. Lubricate O-ring with engine
oil. Tighten adapter nut until O-ring is centered in
groove.
b. Apply anti-seize compound sparingly to adapter
threads, then simultaneously screw adapter and nut
into engine until O-ring seats against engine without
turning adapter nut. Rotate adapter to the approximate angular position noted during removal. Do not
tighten nut at this time.
c. Temporarily install filter assembly on adapter,
and position so adequate clearance with adjacent
parts is attained. Maintaining this position of the
adapter, tighten adapter nut to 50-60 lb-ft and safety.
Use a torque wrench, extension and adapter as necessary.
d. Using new gaskets, install the filter assembly
as outlined during element replacement.
e. Be sure to service the engine oil system, perform the checks and inspections outlined, and resafety all parts requiring safetying, as noted in
paragraph 12-95.
f. Reinstall any component removed for access.

1/2
(TYP)

1 11/16 R-

I 11/16
1 7/32

-\-1 ___

5/32

^1 7/8 R (TYP)

2. 135

MATL:4130

Figure 12-16.

(Rc. 35-38)

Wrench Adapter Fabrication
12-47

DIPSTICK

OIL PUMP

FILTER
BYPASS
-VALVE
FILTER
BYPASS

OIL

OIL
TEMPERATURE

OPTIONAL
EXTERNAL
FILTER (WITH EARLY
TYPE FILTER ADAPTER)
Figure 12-17.

12-48

Engine Oil Schematic (0-200 Series)

CODE
PRESSURE OIL FROM
GEAR TYPE OIL PUMP

SUMP OIL, SUCTION OIL, AND
RETURN OIL FROM RELIEF
VALVE

.....

.... .

. .

....

DIP STICK

_____ ^RELIEF

OIL

111

TEMPERATREALL
GAGE

FILTER

Figure 12-18.
ISOLATIOl.

Engine

TEMPERATr-REFILTER

FILTER

VALVE

1
FILTE R (WITH EARLY

/OPOTINAL
TYPE
FILTER ADAPTER)
FLPRESSURE
AL

Oil Schematic (0-300 Series)
12-49

CODE
CODE

OIL COOLER

THERMOSTAT

PRESSURE OIL FROM GEAR

(THERMOSTAT OPEN)

SUMP OIL, SUCTION OIL, AND
RETURN OIL FROM RELIEF VALVE

PROPELLER
CONTROL

TO
PROPELLER
THERMOSTAT
OILDIPL
COOLER
THERMOSTAT CLOSED)

PROPELLER
GOVERNOR

PRESSURE
GAGE

OIL
TEMPERATURE
GAGE

OIL DIP STICK.

HIGH PRESSURE
OIL FILTER SCREEN

ENGINE
OIL PUMP

Figure 12-19.
12-50

LOW PRESSURE
OIL FILTER SCREEN

Engine Oil Schematic (GO-300 Series)

THERMOSTAT
OPEN

THERMOSTAT

PLUG

THERMOSTAT
OPEN

CLOSED

STANDARD
OIL COOLER

NON-CONGEALING
OIL COOLER
TO
PROPELLER

PROPELLER
CONTROL ~~~~~~CONTROL
fl~ir~lt.

-».

- '"~
PRPLLER
F||OIL

-PLUG
\PLU

THERMOSTAT
/--UG CLOSED

C'"D^ P~ \
Ap

= --

NON-CONGEALING
COOLER

PROPELLER
P
GOVERNOR

.PLE
'
\.

............ ......

FILLER:
CAP
OIL

OIL

if I I

NOTE
llj

^"^*,^^~

/
* iG2

0-470, 10-470, and 10-520 series filter
shown. The other filters are one-piece
and cannot be disassembled. This filter
is replaced with an adapter when the external oil filter is installed.

1.
2.
3.
4.
5.
6.

Perforated Tube
Element Casket
Element
Head Casting
Washer
Bolt

Figure 12-21.
12-98.

EXHAUST SYSTEM.

12-99. Exhaust system configurations used on
Cessna airplanes vary with each model; however,
all are similar in principle of operation. Exhaust
gas heat exchangers, shrouds, ducting, valves, and
controls furnish heated air to the engine intake system or cabin, or both.
12-100. REMOVAL AND REPLACEMENT of exhaust
systems may be accomplished as follows:
a. Remove engine cowling.
b. Disconnect ducting from heater shrouds.
c. Disconnect exhaust stack braces.
d. Remove nuts securing the exhaust stack assembly to the cylinders.
NOTE
Usually the assembly can be removed intact.
However, on some models the clamps joining
sections of the exhaust stacks must be removed and the assembly removed in sections
because of engine mount or engine component
interference,
e. Heater shrouds may be removed as desired.
f. Reverse the above procedure to install the exhaust system. Use new exhaust gaskets regardless
of apparent condition of those removed.
12-101. INSPECTION of the exhaust system should
be thorough because the cabin heating system uses
air heated by the heat exchangers of the exhaust sys12-52

Engine Oil Filter
tem. Since exhaust systems of this type are subject to burning, cracking, and general deterioration
from alternate thermal stresses and vibration (comparable to those affecting automotive mufflers), inspection is important and should be accomplished
every 100 hours of operation. In addition, an inspection should be performed any time exhaust
fumes are detected in the cabin.
a. Remove engine cowling, and loosen or remove
heater shrouds so that ALL surfaces of the exhaust
stack assembly can be visually inspected. Especially check the areas adjacent to welds. Look
for exhaust deposits in surrounding areas, indicating that exhaust gas is escaping through a crack
or hole.
b. Where part of the exhaust stack assembly is
not accessible for a thorough visual inspection, or
is hidden by parts of non-removable shrouds, the
following method is recommended.
1. Remove the exhaust stack assembly and
heater shrouds in accordance with paragraph 12-100.
2. Use rubber expansion plugs to seal openings.
3. Using a manometer or gage, apply approximately 1 1/2 psi (3 inches of mercury) air pressure
while the stack assembly is submerged in water.
Any leaks will appear as bubbles and can be readily
detected.
4. It is recommended that any exhaust stacks
found defective be replaced before the next flight.
5. If no defects are found, remove plugs and
dry thoroughly with compressed air.
c. Install the exhaust system by reversing the
procedure of paragraph 12-100.

SECTION 12A
ENGINE
(LYCOMING "BLUE-STREAK")

TABLE OF CONTENTS

Page

ENGINE COWLING ............
12A-1
Removal and Installation .
......
12A-1
Cleaning and Inspection ........
12A-2
Repair ...............
12A-2
ENGINE ................
12A-2
Engine Data .............
12A-3
Trouble Shooting .........
. 12A-3
Removal
..............
12A-6
Cleaning .
.............
12A-7
Accessories Removal.........
12A-7
Inspection and Repair ........
12A-7
Engine Build-Up ..........
12A-7
Installation .............
12A-7
BAFFLES .........
12A-8
Cleaning and Inspection ...
12A-8
Removal and Installation .......
12A-8
Repair ...............
12A-8
ENGINE MOUNT .............
12A-8
Removal and Installation .......
12A-8
Repair ...............
12A-8
Shock Mount Pads ..........
12A-8
ENGINE OIL SYSTEM. ..........
12A-9
Trouble Shooting .......
.......
12A-10
Oil Cooler
.............
. 12A-ll
Full-Flow Oil Filter ........
. 12A-11
Filter Element Replacement
. . . 12A-11
Filter Adapter Removal ......
12A-13
Disassembly Inspection and
Assembly ..........
12A-13
Filter Adapter Installation. ....
12A-13
ENGINE FUEL SYSTEM
.........
12A-13

Carburetor Removal and Installation
Idle Speed and Mixture Adjustment
INDUCTION AIR SYSTEM ....
....
Removal and Installation. .......
IGNITION SYSTEM .
.......
.
Magneto Removal ..........
Internal Timing ..........
Replacement Interval .........
Installation and Timing ........
Maintenance
.
..........
Spark Plugs
.
........
ENGINE CONTROLS ..
.......
Rigging ..
..........
Throttle .......
Mixture .
..........
Carburetor Heat .
........
STARTING SYSTEM ...........
Trouble Shooting .
.......
Removal and Installation .......
Primary Maintenance .
....
.
EXHAUST SYSTEM
.
........
Removal. ..............
Inspection .
....
....
...
Installation. ..............
EXTREME WEATHER MAINTENANCE ..
Cold Weather. ............
Ground Service Receptacle. ......
Hot Weather
.
........
Dusty Conditions .
........
Seacoast and Humid Areas
......
Hand Cranking
.
.........

12A-1.

quick-release fasteners. Disconnect any air ducts
and control linkage which interfers with removal of
the cowling. When installing the cowling, be sure to
connect any items disconnected during removal.

ENGINE COWLING.

12A-2. The engine cowling is comprised of an upper
and lower cowl segment. A large access door on the
upper cowl provides access to the fuel strainer drain,
oil filler cap, and oil dipstick. Instead of attaching
directly to the fuselage, the cowling attaches to shock
mounts which, in turn, are fastened to the fuselage.
Quick-release fasteners are used at the cowling-toshock mount and at parting surfaces of upper and
lower cowl attach points to facilitate removal of the
cowling.
12A-3. REMOVAL AND INSTALLATION. Removal
and installation of the engine cowling is accomplished
by removing the attaching screws and releasing the

.
.

12A-13
12A-13
12A-14
12A-14
. 12A-14
12A-14
12A-14
12A-14
12A-14
12A-16
.
12A-16
. 12A-16
.
12A-16
12A-16
12A-17
12A-17
12A-17
. 12A-17
12A-18
. 12A-18
.
12A-18
12A-18
.
12A-20
12A-20
.12A-20
12A-20
12A-20
.
12A-21
12A-21
12A-21
12A-21

NOTE
When new shock mounts or brackets are being
installed, careful measurements should be
made to position these parts correctly on the
firewall. The service parts are not pre-drilled.
Install shock mounts on brackets so that cowling and shock mounts are correctly aligned.
Sheet aluminum may be used as shims between
bracket halves to provide proper cowling contour.
12A-1

12A - 6. CLEANING AND INSPECTION. Wipe the
inner surfaces of the cowl with a cloth saturated with
cleaning solvent (Stoddard solvent, or equivalent).
If he inner surface of the cowl is coated heavily with
grease and dirt, allow solvent to soak until the foreign
material can be removed.. Painted surfaces should
be cleaned by washing with a solution of water and
mild soap. After washing, a coat of wax on painted
surfaces is recommended to prolong paint life. After
cleaning, inspect cowling for dents, cracks, and
loose rivets. Repair all defects to prevent spread of
damage.
12A-5. REPAIR. If cowling skins are extensively
damaged, complete sections of the cowling should be
replaced. Standard insert-type patches may be used
if repair parts are formed to fit. Small cracks may
be-stop.drilled and dents straightened if they are reinforced on the inner side with a-doubler-of the-same-

-......

12A-6.

ENGINE.

12A-7. An air-cooled, wet-sump, horizontalopposed, low-compression, direct-drive, fourcylinder "Blue-Streak" (Lycoming) O-320-E series
engine is used to power the aircraft. The cylinders,
numbered from front to rear, are staggered to permit a separate throw on the crankshaft for each connecting rod. The right front cylinder is number 1
and cylinders on the right side are identified by odd
numbers 1 and 3. The left front cylinder is numbered
2 and the cylinders on the left side are identified as
2 and 4. Refer to paragraph 12A-8 for engine data.
For repair and overhaul of the engine, accessories,
and propeller, refer to applicable publication issued
by-theirmanufacturers.

..........

Quick-Release Fastener

Figure 12A-1.
(2A-2

material. Cowl reinforcement angles, if damaged,
should be replaced.

4.
5.

Asbestos Seal
Shock Mount

Engine Cowling Shock Mounts

Firewall

12A-8.

ENGINE DATA.

Aircraft Series

1721

Lycoming Model ("Blue-Streak")

O-320-E2D

Rated Horsepower at RPM

150 at 2700

Number of Cylinders

4-Horizontally Opposed

Displacement
Bore
Stroke

320 Cubic Inches
5.125 Inches
3.875 Inches

Compression Ratio

7.00:1

Magnetos
Right Magneto
Left Magneto

Slick No. 4051 (left) No. 4050 (right)
Fires 25 ° BTC 1-3 Upper and 2-4 Lower
Fires 25 ° BTC 2-4 Upper and 1-3 Lower

Firing Order

1-3-2-4

Spark Plugs
Gap
Torque

SH-20A
0.015 to 0. 018 Inch
390+30 Lb-In.

Carburetor (Marvel-Schebler)

MA-4SPA

Alternator

14-Volt, 60-Ampere

Starter (12-Volt)

Automatic Engagement

Tachometer

Mechanical

Oil Sump Capacity

8 U.S. Quarts

Oil Pressure (psi)
Minimum Idling
Normal
Maximum (Starting & Warm-Up)

25
60-90
100

Cylinder Head Temperature
Normal Operating
Maximum

Within Green Arc
Red Line (500°F)

Direction of Propeller Shaft
Rotation (viewed from rear)

Clockwise

Dry Weight - with Accessories

269 lb (Weight is approximate and
will vary with optional equipment
installed.)

12A-9.

TROUBLE SHOOTING.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

ENGINE FAILS TO START.
Review starting procedure.

Improper use of starting
procedure.
Defective aircraft fuel
system.

See paragraph 13-3.

12A-3

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

ENGINE FAILS TO START (Cont).
Engine flooded.

See paragraph 12A-68.

Spark plugs fouled or
improperly gapped.

Remove and check.

Clean and regap.
defective.

Failure of magneto impulse
coupling.

With ignition switch off, rotate
propeller by hand and listen for
loud click as impulse coupling
operates.

Repair or replace magneto.

Defective magneto switch
or grounded magneto leads.

Check continuity.

Repair or replace switch
or leads.

Defective ignition system.

See paragraph-12A-48;

Seeparagraph 12A-48.

Excessive induction air leaks.

Check visually.

Correct the cause of air leaks.

Vaporized fuel.

Vaporized fuel is most likely
to occur in hot weather with
a hot engine.

See paragraph 12A-68.

Defective carburetor.

If engine will start on primer
but stops when mixture is
placed in full rich position and
priming is discontinued, the
carburetor is defective.

Repair or replace carburetor.

Water in fuel system.

Open fuel strainer drain valve
and check for water.

Drain fuel tank sumps, fuel lines,
fuel strainer, and carburetor.

Replace if

ENGINE STARTS BUT DIES, OR WILL NOT IDLE.
Defective aircraft fuel system.

See paragraph 13-3.

Improper idle speed or idle
mixture adjustment.

See paragraph 12A-38.

Spark plugs fouled or improperly gapped.

Remove and check.

Clean and regap.
defective.

Water in fuel system.

Open fuel strainer drain
valve and check for water.

Drain fuel tank sumps, fuel lines,
fuel strainer and carburetor.

Defective ignition system.

See paragraph 12A-48.

Excessive induction air
leaks.

Check visually.

Correct the cause of air leaks.

Vaporized fuel.

Vaporized fuel is most likely
to occur in hot weather with
a hot engine.

See paragraph 12A-38.

Manual primer leaking.

Disconnect primer outlet line.
If fuel leaks through primer,
it is defective.

Repair or replace primer.

12A-4

Replace if

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

ENGINE STARTS BUT DIES, OR WILL NOT IDLE (Cont).
Leaking float valve or float
level set too high.

Perform an idle mixture check.
Attempt to remove any rich
indication with idle mixture
adjustment. If the rich indication cannot be removed, the
float valve is leaking or the
float level is set too high.

Replace defective parts; reset
float level.

Defective carburetor.

If engine will start on primer
but stops when mixture is
placed in full rich position and
priming is discontinued, the
carburetor is defective.

Repair or replace carburetor.

Defective engine.

Check compression. Listen
for unusual engine noises.

Engine repair is required.

ENGINE RUNS ROUGHLY OR WILL NOT ACCELERATE PROPERLY.
Restriction in aircraft fuel
system.

See paragraph 13-3.

Worn or improperly rigged
throttle or mixture control.

Check visually.

Rig properly.
linkage.

Spark plugs fouled or improperly gapped.

Remove and check.

Clean and regap.
defective.

Defective ignition system.

See paragraph 12A-48.

Defective or badly adjusted
accelerating pump in carburetor.

Check setting of accelerating
pump linkage.

Change accelerating pump
adjustment.

Float level set too low.

Check float level.

Reset float level.

Defective carburetor.

If engine will start on primer
but stops when mixture is
placed in full rich position and
priming is discontinued, the
carburetor is defective.

Repair or replace carburetor.

Defective engine.

Check compression. Listen
for unusual engine noises.

Engine repair is required.

Restricted carburetor air
filter.

Check visually.

Clean air filter as outlined in
paragraph 2-17.

Cracked engine mount.

Inspect engine mount.

Replace mount.

Defective mounting bushings.

Inspect visually.

Install new mounting bushings.

Replace worn
Replace if

12A-5

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

POOR IDLE CUT-OFF.
Worn or improperly rigged
mixture control.

Check that idle cut-off stop on
carburetor is contacted.

Rig properly.
linkage.

Manual primer leaking.

Disconnect primer outlet line.
If fuel leaks through primer,
it is defective.

Repair or replace primer.

Defective Carburetor.

If engine will start on primer
but stops when mixture is
placed in full rich position and
priming is discontinued, the
carburetor is defective.

Repair or replace carburetor.

Fuel contamination.

Check all screens in-fuel
system.

Drain-all fuel and flush out fuel
system. Clean all screens,
fuel lines, fuel strainer, and
carburetor.

12A-10. REMOVAL. I the engine is to be placed in
storage or returned to the manufacturer, proper preparatory steps should be taken prior to beginning the
removal procedure. Refer to Section 2 for preparing
the engine for storage. The following engine removal
procedure is based upon the engine being removed
from the aircraft with the engine mount attached to
the firewall and all engine connections being disconnected at the firewall.
NOTE
Tag each item disconnected to aid in identifying wires, hose, lines, and control linkage
when the engine is being installed. Protect
openings, exposed as a result of removing or
disconnecting units, against entry of foreign
material by installing covers or sealing with
tape.
a. Place all cabin switches and fuel valves in the
OFF position.
b. Remove engine cowling. (See paragraph 12A-3.)
c. Open battery circuit by disconnecting battery
cables(s).
d. Disconnect ignition switch (primary) leads at
magnetos.

WARNING
These magnetos DO NOT have internal grounding springs. The magneto is in a SWITCH ON
condition when the primary (ignition) lead is
disconnected. Ground the magneto breaker
points or remove the high tension outlet plate

to prevent accidental firing when the propeller

Replace worn

NOTE
During the following procedures, remove any
clamps which secure controls, wires, hose or
lines to the engine, engine mount, or attached
brackets, so they will not interfere with removal of the engine.
g. Disconnect throttle and mixture control at carburetor. Pull these controls free of engine, using
care not to damage them by bending too sharply.
Note position, size and number of attaching washers
and spacers.
h. Loosen clamps and remove flexible duct from
engine baffle and oil cooler duct.
i. Loosen clamps and remove flexible ducts from
muffler shroud and heater valve.
j. Disconnect carburetor heat control at airbox
and remove clamp attaching control to bracket. Pull
control aft to clear engine.
k. Disconnect wires and cables as follows:
1. Tachometer drive shaft at adapter on engine.
2. Starter electrical cable at starter.
3.
Electrical wires and wire shielding ground
at alternator.
4. Cylinder head temperature at lower side of
cylinder.
5. Remove all clamps attaching wires or cables

to engine.

Pull all wires and cables aft to clean en-

gine.
1. Disconnect lines and hose as follows:
1. Vacuum pump hose at firewall fitting.
2. Engine breather hose at top of accessory
case.

WARNING

is rotated.
e.
f.

32A-6

Drain the engine oil.
Remove propeller. (See paragraph 14A-4.)

Residual fuel and oil draining from disconnected lines and hose is a fire hazard. Use
care to prevent accumulation of such fuel
and oil.

3. Oil temperature bulb at adapter on engine.
4. Primer line at fidewall fitting.
5. Fuel hose at carburetor.
6. Oil pressure line at firewall fitting.
7. Oil cooler hose at oil cooler and firewall.
8. Remove all clamps attaching hose and lines
to engine mount and brackets.
m. Attach a hoist to the lifting strap on top of the
engine and take up engine weight on hoist.

Place a stand under the tail tie-down fitting
before removing the engine. The loss of engine weight will allow the tail to drop. Do not
raise the engine higher than necessary when
removing the engine-to-mount attach bolts.
Raising the engine too high places a strain on
the attach bolts and hinders removal.
n. Remove bolts attaching engine-to-engine mount.
Balance the engine by hand as the last of these bolts
are removed.
CAUTION
Hoist engine slowly and ascertain that all items
attaching engine and accessories to the airframe are disconnected.
o. Carefully guide disconnected components out of
engine assembly.
12A-11. CLEANING. The engine may be washed
down with a suitable solvent, such as Stoddard solvent, or equivalent, then dried thoroughly.

not available

12A-12. ACCESSORIES REMOVAL. Removal of
engine accessories for overhaul or engine replacement involves stripping the engine of parts, accessories, and components to reduce it to the bare engine. During removal, removed items should be
examined carefully, and defective parts should be
tagged for repair or replacement.

12A-14. ENGINE BUILD-UP. Engine build-up consists of installation of parts, accessories, and components to the basic engine to build-up an engine unit
ready for installation on the aircraft. All safety
wire, lockwashers, Palnuts, elastic locknuts, gaskets, and rubber connections should be new parts.
12A-15. INSTALLATION. Before installing the engine, install any items that were removed from the
engine after it was removed from the aircraft.
NOTE
Remove

and
identification
tags
each item in
and identification tags as
as each item is connected or installed.

a. Hoist engine assembly to a point near the engine
mount.
b. Route controls, lines, and hose in place as the
engine is positioned near the mount.
c. Install engine-to-mount bolts. Install shock
c. Install engine-to-mount bolts
mounts as shown in figure 12A-2 Tighten engineto-mount bolts to the torque value shown in figure
2.
d. Remove hoist and support stand placed under
tail tie-own fitting.
e. Route throttle, mixture, and carburetor heat
controls to the carburetor and airbox and connect.
Secure controls in position with clamps.
NOTE
Throughout the aircraft fuel system, from the
tanks to the carburetor, use Parker Sealube
(or equivalent) as a thread lubricant or to seal
a leaking connection. Apply lubricant sparingly
to male fitting threads only, omitting the first
two threads. Always be sure that a compound.
the residue from a previously used compound,
or any other foreign material cannot enter the
system.

NOTE
Items easily confused with similar items should
be tagged to provide a means of identification
when being installed on a new engine. All
openings exposed by the removal of an item
should be closed by installing a suitable cover
or cap over the opening. This will prevent entry of foreign particles. If suitable covers are

cover the

12A-13. INSPECTION AND REPAIR. For specific
items to be inspecter refer to the engine manfacturer's manual.
a. Inspect all hose for internal swelling chafing
through protetive plys, cuts and breaks hardening,
and loose connections. Excessive heat on hose will
cause them to become brittle and easily broken.
Hose and lines are most likely to crack or break near
the end fittings and support points.
b. Inspect all fittings and mating parts for damaged
threads.
c. Visually inspect the engine for loose nuts, bolts,
cracks and fin damage.
d. Inspect baffles, baffle seals, and brackets for
cracks, deterioration, and breakage.
e. For major repairs, refer to the manufacturer's
overhaul and repair manual.

CAUTION
Particular care should be given to electrical
equipment before cleaning. Solvent should not
be allowed to enter magnetos, starters, alternators, and the like. Hence, these components should be protected before saturating the
engine with solvent. Any fuel, oil and air openings on the engine and accessories should be
covered before washing the engine with solvent.
should
solutions
cleaning
Caustic cleaning solutions
should be
be used
used
cautiously and should always be properly neutralized after their use.

tape

Connect lines and hose as follows:
1. Oil cooler hose at oil cooler on firewall.
2. Oil pressure line at firewall fitting.
12A-7

3.
Fuel hose at carburetor.
4. Primer line at firewall fitting.
5. Oil temperature bulb at adapter on engine.
6. Engine breather hose at top of accessory
case.
7. Vacuum pump hose at firewall fitting.
8. Install clamps attaching hose and lines to
engine mount and brackets.
g. Connect wires and cables as follows:
1. Cylinder head temperature at lower side of
cylinder.
2. Electrical wires and wire shielding ground
at alternator.
3. Starter electrical cable at starter.
4. Tachometer drive shaft at adapter on engine.
Be suredrive cableengages drive in adanter.
Torque housing attach nut to 100 lb-in.
5. Install clamps curing wires and cables to
engine, engine mount, and brackets.
h. Install flexible duct to heater valve and baffle,
and duct to heater valve and muffler shroud. Tighten
clamps.
i. Install flexible duct to engine baffle and oil cooler
shroud. Tighten clamps.
J. Install propeller and spinner. (Refer to paragraph 14A-5.)
k. Make a magneto switch ground-out and continuity check. Connect ignition switch (primary) leads
to magnetos. Remove temporary ground.

WARNING
Be sure magneto switch is in OFF position before connecting switch (primary) leads to magnetos.
1. Service engine with proper grade and quantity of
engine oil. Refer to Section 2 if engine is new, newly
overhauled, or has been in storage.
m. Make sure all switches are in the OFF position,
and connect battery cables.
n. Rig throttle, mixture, and carburetor heat controls in accordance with paragraph 12A-53 through
12A-56.
o. Check engine installation for security, correct
routing of controls, lines, hose, and electrical
wiring, proper safetying, and tightness of all cornponents.
p. Install engine cowling. Be sure all hot and cold
air ducts are connected,
q. Perform engine run-up and make final adjustments on engine controls.
12A-16. BAFFLES.
12A-17. The sheet metal baffles installed on the engine direct the flow of air around the cylinders and
other engine components to provide optimum cooling
of the engine. These baffles incorporate rubberasbestos composition seals at points of contact with
the engine cowling to help confine and direct the airflow to the desired area. It is very important to engine cooling that the baffles and seals are installed
correctly and maintained in good condition.
12A-18. CLEANING AND INSPECTION. The engine
baffles should be cleaned with a suitable solvent to
12A-8

remove oil and dirt.
NOTE
The rubber-asbestos seals are oil and grease
resistant but should not be soaked in solvent for
long periods.
Inspect baffles for cracks in the metal and for loose
and/or torn seals. Replace or repair defective parts.
12A-19. REMOVAL AND INSTALLATION. Removal
and installation of the various baffle segments is possible with the cowling removed. Be sure that any replaced baffles and seals are installed correctly and
that they seal to direct the airflow in the correct direction.
12A-20. REPAIR. Baffles ordinarily should be replaced if damaged or cracked. However, small plate
reinforcements riveted to the baffle will often prove
satisfactory both to the strength and cooling requirements of the unit.
12A-21.

ENGINE MOUNT.

12A-22. The engine mount is composed of sections
of tubing welded together and reinforced with welded
gussets. The purpose of the mount is to support the
engine and attach it to the airframe. The engine is
attached to the engine mount with shock-mount

assemblies which absorb engine vibrations and prevent transmission of these vibrations to the airframe.
12A-23. REMOVAL AND INSTALLATION. Replacement of the engine mount necessitates removal of the
engine, followed by removal of the bolts attaching the
mount to the fuselage at the firewall. When installing
engine mount, tighten mount-to-fuselage bolts, and
engine mount-to-engine bolts to the torque value
shown in figure 12A-2.
12A-24. REPAIR. Repair of the engine mount should
be performed carefully as outlined in Section 19 of the
Service Manual. The mount should be painted with
heat-resistant black enamel after welding or whenever
the original finish has been removed.
12A-25. SHOCK MOUNT PADS. The bonded rubber
and metal shock mounts are designed to reduce transmission of engine vibrations to the airframe. The
rubber pads should be wiped clean with a dry cloth.
NOTE
Do not clean the rubber parts with any type of
cleaning solvent.
Inspect metal parts for cracks and excessive wear
due to aging and deterioration. Inspect the rubber
parts for swelling, cracking, or a pronounced set of
the part. Replace all parts that show evidence of
wear or damage.

MOUNT-TO- FIREWALL

(UPPER)

ENGINE-TO-MOUNT
(UPPER)
1

TORQUE MOUNT-TO-FIREWALL
BOLTS TO 160 - 190 LB-IN

22
1

TORQUE ENGINE-TO-MOUNT
,

BOLTS TO 450 - 500 LB-IN

MOUNT-TO-FIREWALL
(LOWER)
NOTE
When installing shock mounts, install shock mount pad (8) as
shown for the upper and lower mounts. Also, note on lower
mount, washer (4) is installed between engine mount foot and
shock mount. This is to prevent starter ring gear from coming in contact with lower cowling.
1.
2.
3.

8. Shock Mount Pad
4. Washer
Nut
9. Shock Mount Dampener
5. Firewall
Washer
10. Shock Mount Pad
Engine Mount 6. Bolt
7. Engine Mount Foot

Figure 12A-2.
12A-26.

ENGINE OIL SYSTEM.

12A-27. The engine lubricating system is of the full
pressure, wet sump type. The main bearings, connecting rod bearings, camshaft bearings, valve
tappets, and push rods, are lubricated by positive
pressure. The pistons, piston pins, cams cylinder
walls, valve rockers, valve stems, and other moving
parts are lubricated by oil collectors and oil spray.
The oil pump, which is located in the accessory
housing, draws oil through a drilled passage leading
from the oil suction screen located in the sump.
From the pump, the oil enters a drilled passage to a
threaded connection and through a flexible hose to the
oil cooler. Pressure oil from the oil cooler returns
through a flexible hose to a threaded connection on
the accessory housing. From there the oil flows
through a drilled passage to the oil pressure screen
which is contained in a cast chamber mounted on the
accessory housing. If cold oil or obstruction should
restrict the flow of oil through the cooler, an oil
cooler bypass valve is provided to pass the pressure
oil directly from the oil pump to the oil pressure
screen. The oil is then filtered through the oil pressure screen chamber and fed through a drilled passage to the oil pressure relief valve which is located
in the upper right side of the crankcase forward of

$
ENGINE-TO-MOUNT
(LOWER)

Engine Mount Details
the accessory housing. This relief valve regulates
the engine oil pressure by allowing excessive oil to
return to the sump, while the balance of the pressure
oil is fed to the main oil gallery in the right half of
the crankcase. The oil is distributed from the main
gallery by means of a separate drilled passage to
each main bearing of the crankshaft. The drilled
passages to the bearings are located in such a manner as to form an inertia type filter, thus ensuring
that only the cleanest oil will reach the bearings.
Drilled passages from the rear main bearing supply
pressure oil to the crankshaft idler gears. Angular
holes are drilled through the main bearings to the
rod journals where sludge removal tubes are located.
Oil from the main gallery also flows to the cam and
valve gear passages, and then is conducted through
branch passages to the hydraulic tappets and camshaft bearings. Oil travels out through the hollow
push rods to the valve rocker bearings and valve
stems. Residual oil from the bearings, accessory
drives, and rocker boxes flows by gravity to the
sump where it passes through the suction screen and
is re-circulated through the engine. The oil cooler
is controlled by a thermostat valve. An external,
replaceable element oil filter is available as optional
equipment. This external filter replaces the pressure oil screen when installed.
12A-9

12A-28.

TROUBLE SHOOTING.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

NO OIL PRESSURE.
No oil in sump.

Check with dipstick.

Fill sump with proper grade and
amount of oil.

Oil pressure line broken,
disconnected, or pinched.

Inspect oil pressure line.

Replace or connect.

Oil pump defective.

Remove and inspect.

Examine engine. Metal particles
from damaged pump may have
entered-engine oilpassages.

Defective oil pressure
gage.

Check with another gage. If
second reading is normal, airplane gage is defective.

Replace gage.

Oil congealed in gage
line.

Disconnect line at engine and
gage; flush with kerosene.

Pre-fill with kerosene and
install.

Relief valve defective.

Remove and check for dirty or
defective parts.

Clean and reinstall; replace if
defective.

LOW OIL PRESSURE.
Low viscosity oil.

Drain oil and refill sump with
proper grade of oil.

Low oil level.

Check with dipstick.

Fill sump to proper level with
proper grade of oil.

Oil pressure relief valve
spring weak or broken.

Remove and check spring.

Replace weak or broken spring.

Defective oil pump.

Check oil temperature and oil
level. If temperature is higher
than normal and oil level is correct, internal failure is evident.

Examine engine. Metal particles
from damaged oil pump may have
entered engine oil passages.

Secondary result of high
oil temperature.

Observe oil temperature gage
for high indication.

Determine and correct reason
for high oil temperature.

Leak in suction line or
pressure line.

Check gasket between accessory
housing and crankcase.

Engine repair is needed.

Dirty oil suction and/or
pressure screen.

Inspect oil screens.

Remove and clean suction
pressure oil screens.

HIGH OIL PRESSURE.
High viscosity oil.

Drain oil and refill sump with
proper grade and amount of oil.

Relief valve defective.

Remove and check for dirty or
defective parts.

Clean and reinstall; replace if
defective.

Defective oil pressure gage.

Check oil pressure with another
gage.

Replace oil pressure gage.

12A-10

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

HIGH OIL TEMPERATURE.
Oil cooler thermostat defective.

Feel front of cooler core with
hand. If core is cold, oil is
bypassing cooler.

Replace thermostat.

Oil cooler air passages clogged.

Inspect cooler core.

Clean air passages.

Oil cooler oil passages clogged.

Attempt to drain cooler. Inspect
any drainings for sediment.

Clean oil passages.

Oil congealed in oil cooler.

This condition can only occur
in extremely cold temperatures.

If congealing is suspected, use
external heater or a heated
hangar to thaw the congealed oil.

Secondary effect of low oil
pressure.

Observe oil pressure gage for
low indication.

Determine and correct reason
for low oil pressure.

Defective oil temperature
gage.

Check with another gage. If
second reading is normal, airplane gage is defective.

Replace gage.

Defective oil temperature
bulb.

Check for correct oil pressure,
oil level and cylinder head temperature. If they are correct,
check oil temperature gage for
being defective; if a similar reading is observed, bulb is defective.

Replace temperature bulb.

Defective oil temperature bulb
or gage.

Check with another gage. If reading is normal, airplane gage is
defective. If reading is similar,
temperature bulb is defective.

Replace defective part.

Oil cooler thermostat defective
or stuck closed.

Remove valve and check for
proper operation.

Replace thermostat.

LOW OIL TEMPERATURE.

12A-29. OIL COOLER. The fin and plate oil cooler
is mounted on the right firewall and receives its
cooling air from the engine compartment. Oil under
pressure from the oil pump enters the inboard side
of the cooler, passes through the cooler and back to
the engine. A thermostatically operated oil cooler
bypass valve, installed in the oil pressure screen
mounted pad or external filter adapter, causes oil
to bypass the cooler in the event of congealed oil or
an obstruction in the cooler. The bypass valves
passes the oil directly to the pressure screen or
external filter until a predetermined oil temperature
is reached, then the oil is routed through the cooler
to be cooled.
12A-30. FULL-FLOW OIL FILTER. An optional
external oil filter may be installed on the engine.
The filter and filter adapter replace the regular
engine oil pressure screen and cast chamber on the
accessory case. The adapter incorporates mounting provisions for the thermostatic oil cooler bypass

valve and oil temperature bulb. If the filter element
should become clogged, the bypass valve allows
engine oil to flow to the engine oil passages.
12A-31. FILTER ELEMENT REPLACEMENT.
figure 12A-3.)
NOTE

(See

Filter element replacement kits are available from the Cessna Service Parts Center.
a. Remove engine cowling as necessary for access.
b. Remove both safety wires from filter can and
unscrew hollow stud to detach filter assembly from
adapter as a unit. Remove from airplane, discarding gasket.
c. Remove nylon nut from hollow stud at top of lid
and press downward on stud to remove.
d. Lift lid off filter can, discarding gasket.

12A-l1

NOTE
One side of gasket (1) is marked
ENGINE SIDE, this side of the gasket must be installed toward the
engine.

ENGINE (REF)
1.
2.
3.
4.
5.

Gasket
Adapter
Oil Temperature
Oil Temperature Bulb
Gasket

6.
7.
8.
9.

Nylon Nut
Lid
Gasket
Filter Element

10.
11.
12.
13.
14.

Filter Can
Copper Gasket
Hollow Stud
Safety Wire Tab
Thermostatic Valve

Figure 12A-3. Full-Flow Oil Filter

Pull filter element out of can.
NOTE
Before discarding removed filter element,
remove the outer perforated paper cover;
using a sharp knife, cut through the folds of
the filter element at both ends, close to the
metal caps. Then, carefully unfold the pleated element and examine the material trapped in the filter element for evidence of internal engine damage such as chips or particles from bearings. In new or newly overhauled engines, some small particles or
metallic shavings might be found, these are
generally of no consequence and should not
be confused with particles produced by impacting, abrasion, or pressure. Evidence
of internal engine damage found in the oil
filter element justifies further examination
to determine the cause.

12A-12

Wipe parts clean with a soft cloth.
NOTE
When installing a new filter element, it is
important that all gaskets are clean, lubricated, and positioned properly, and that the
correct amount of torque is applied to the
filter attaching stud. If the stud is undertorqued, oil leakage will occur. If the stud
is over-torqued, the filter can may be deformed, again causing oil leakage.
Lubricate rubber grommets in new filter
element, gaskets and metal gasket with
clean engine oil or general purpose grease
before installation. Dry gaskets may
cause false torque readings, again resuiting in oil leakage.

Before assembly, place a straightedge
across bottom of filter can. Check for a
distortion or out-of-flat condition greater
than 0. 010 inch. Replace if either of these
conditions exists.
After installing a new gasket on lid, turn it
upside down. If gasket falls, replace gasket and repeat test. If this gasket falls off,
replace lid.
g. Inspect adapter gasket seat for gouges, deep
scratches, wrench marks, and mutilation. If any of
these are found, replace adapter.
h. Place new element in can and insert stud with
new metal gasket in place, through the can and
element.
i. Position new gasket inside flange of lid. Place
lid in position and install nylon nut. The nylon nut
should be snugly seated against lid by fingertightening. The nylon nut must not protrude above
the metal surface of the lid.
j. Install filter assembly on adapter with safety
wire tabs on can down. Holding can to prevent it
from turning, tighten stud and torque to 20-25 Ib-ft,
using a torque wrench.
k. Reinstall parts removed for access, and service
the engine with proper grade and quantity of oil. One
additional quart of oil is required each time the element is replaced.
1. Start engine and check for proper oil pressure.
Check for leaks after warming up engine.
m. Again check for leaks after engine has been run
at a high power setting (preferably a flight around
the field).
n. Check to make sure filter has not been making
contact with adjacent parts due to engine torque.
o. While engine is still warm, recheck torque on
stud, then safety stud to bracket on filter can, and
safety thermostatic valve to bracket on filter can.
12A-32. FILTER ADAPTER REMOVAL. (See figure
12A-3.)
a. Remove filter assembly as outlined during element replacement.
b. Remove oil temperature bulb from adapter.
c. Remove three bolts and washers attaching
adapter to accessory case.
d. Remove nut and washers attaching lower left
corner of adapter to accessory case and remove
adapter.
e. Remove gasket from mounting pad and discard.
12A-33. DISASSEMBLY, INSPECTION, AND ASSEMBLY OF FILTER ADAPTER. After removal of the
adapter, remove thermostatic valve for cleaning,
Do not disassemble thermostatic valve. Clean
adapter and thermostatic valve in cleaning solvent
and dry with compressed air. Ascertain that all
passages in adapter are open. Remove any gasket
material that may have adhered to adapter. Inspect
adapter for cracks, damaged threads, scratches or
gouges to adapter gasket seats. If any of these are
found replace adapter. Using a new gasket, install
thermostatic vr.'.e in adapter.

12A-34. FILTER ADAPTER INSTALLATION.
a. Using a good grade of gasket sealent, install a
new gasket on accessory case mounting pad. Note
that one side of the gasket is marked ENGINE SIDE;
this side of the gasket must be installed toward the
engine.
b. Install adapter on mounting pad and install bolts,
washers and nut. Use plate washer between the
lockwasher on bolt or nut.
c. Tighten bolts and nut to 75 Ib-in.
d. Install oil temperature bulb.
e. Install filter element as outlined in paragraph
12A-31.
f. Install any components removed for access.
12A-35.

ENGINE FUEL SYSTEM.

12A-36. The engine is equipped with a carburetor of
the single barrel, float type. This carburetor is
equipped with a manual mixture control, and an idle
cut-off. It will be found mounted in the standard updraft position on the bottom of the sump. For repair
and overhaul of the carburetor refer to the manufacturer's overhaul and repair manual.
12A-37. CARBURETOR REMOVAL AND INSTALLATION.
a. Place fuel valve in OFF position.
b. Remove engine cowling.
c. Disconnect throttle and mixture controls at carburetor. Note position, and size of washers and
spacers so that they may be installed in the same
position.
d. Disconnect and cap or plug fuel line at carburetor.
e. Remove induction airbox.
f. Remove nuts and washers attaching carburetor
to intake manifold and remove carburetor.
g. Installation of the carburetor is the reversal of
the preceding steps. Use new gaskets between carburetor and intake manifold.
12A-38. IDLE SPEED AND MIXTURE ADJUSTMENT
should be accomplished after the engine has been
warmed up. Since idle rpm is affected by idle mixture, it will be necessary to readjust the idle rpm
after setting the idle mixture.
a. Set the throttle stop screw to obtain between 500
and 600 rpm, with throttle closed.
NOTE
Engine idle speed will vary among different
engines. An engine should idle smoothly, without excessive vibrations, and the idle speed
should be high enough to maintain idling oil
pressure and to preclude any possibility of
engine stoppage in flight when the throttle is
closed.
b. Advance throttle to increase engine speed to
1000 rpm.
c. Pull mixture control knob slowly and steadily
toward idle cut-off position, observing tachometer,
then return control to full in position before engine
stops.

12A-13

d. Adjust mixture adjusting screw at upper end of
carburetor intake throat to obtain a slight and momentary gain of 25 rpm maximum at 100 rpm engine
speed as mixture control is moved from full in toward
idle cut-off position.
e. If mixture is set too LEAN, engine speed will
drop immediately, thus requiring a richer mixture,
Turn adjusting screw out counterclockwise for richer
mixture.
f.
If mixture is set too RICH, engine speed will increase above 25 rpm, thus requiring a leaner mixture. Turn adjusting screw In (clockwise) for leaner
mixture.
NOTE
After each adjustment to the idle mixture, run
engine up to approximately 2000 rpm to clear
engine of excess fuel and obtain a correct idle
speed.
12A-39.

INDUCTION AIR SYSTEM.

12A-40. Ram air to the engine enters the induction
airbox through an opening in the forward part of the
lower engine cowling nose cap. The air is filtered
through a filter which is located at the opening in the
nose cap. From the induction airbox the air is directed to the inlet of the carburetor, mounted on the
lower side of the engine oil sump, through the carburetor to the center zone induction system, which
is integral with the oil sump. From the center zone
system, the fuel-air mixture is distributed to each
cylinder by separate steel intake pipes. The intake
pipes are attached to the center zone risers with
hose and clamps and to the cylinder with a two bolt
flange which is sealed with a gasket. The induction
airbox contains a valve, operated by the carburetor
heat control in the cabin, which permits air from an
exhaust heated source to be selected in the event
carburetor icing or filter icing should be incountered.
12A-41. REMOVAL AND INSTALLATION.
a. Remove cowling as required for access.
b. Mark the intake pipes as they are removed from
the engine so they may be reassembled in the same
location from which they are removed.
c. Loosen hose clamps and side hose connection
from sump.
d. Remove two nuts, washers, and lock washers
at cylinder.
e. Remove intake pipe and clean gasket from cylinder mounting pad and intake pipe flange.
f.
Installation of the intake pipes is the reversal of
the removal. Use new gasket when installing and install pipes in the same location from which they were
removed,
12A-42.

IGNITION SYSTEM.

12A-43. Sealed, lightweight Slick magnetos are
used on the aircraft. Magneto Model No. 4051 incorporating an impulse coupling is used as the left
magneto, while magneto Model No. 4050 (direct
drive) is used as the right magneto. These magnetos
MUST NOT BE DISASSEMBLED. Internal timing is
fixed and breaker points are not adjustable. Timing
12A-14

marks are provided on the distributor gear and distributor block, visible through the air vent holes,
for timing to the engine. A timing hole is provided
in the bottom of the magneto adjacent to the magneto flange. A timing pin (or 0.093 inch 6-penny
nail) is inserted through this timing hole into the
mating hole in the rotor shaft to lock the magneto
approximately in the proper firing position.

During all magneto maintenance always take
proper precautions to make sure the engine
cannot fire or start when the propeller is
moved.
-12A-44.-MAGNETO REMOVAL. Remove hightension outlet plate, disconnect capacitor lead
(ignition switch lead), and remove nuts and washers
securing magneto to the engine. Note the approximate angular position at which the magneto is installed, then remove the magneto from engine.
12A-45. INTERNAL TIMING. Internal timing is
accomplished during manufacture of the magneto.
Since these magnetos are NOT TO BE DISASSEMBLED, there is no internal timing involved.
12A-46. REPLACEMENT INTERVAL. It is recommended that these magnetos be replaced at engine
overhaul periods.
12A-47. MAGNETO INSTALLATION AND TIMING
TO ENGINE. The magneto must be installed with
its timing marks correctly aligned, with number
one cylinder on its compression stroke, and with the
number one piston at its advanced firing position.
Refer to paragraph 12A-8 for the advanced firing
position of number one piston. To locate the compression stroke of the number one cylinder, remove
the lower spark plug from number 2, 3 and 4 cylinders. Remove the upper spark plug from number 1
cylinder and then place the thumb of one hand over
the spark plug hole of number one cylinder and rotate
crankshaft in the direction of normal rotation until
the compression stroke is indicated by positive pressure inside the cylinder lifting the thumb off the spark
plug hole. After the compression stroke is attained,
locate number one piston at its advanced firing position. Locating the advanced firing position of number one pistion may be obtained by rotating the crankshaft opposite to its normal direction of rotation until it is approximately 30 degrees before top dead
center (BTC) on the compression stroke of number
one cylinder. Rotate crankshaft in a normal direction of rotation to align the timing mark on the front
face of the starter ring gear support with the drilled
hole in the starter, making sure the final motion of
the ring gear is in direction of normal rotation.
NOTE
The starter ring gear must always be in this
position when either magneto is locked in
position.

When the cylinder is in the correct firing position,
install and time the magneto to the engine in the
following manner.
NOTE
Install the magneto drive coupling retainer and
rubber bushings into the magneto drive gear hub
slot. Insert the two rubber bushings into the retainer with chamfered edges toward the operator
when looking into the magneto mount pad on the
engine.
a. Remove the ventilating plug from the bottom of
the magneto. The ventilating plug in the top of the
magneto need not be removed.
b. Rotate magneto shaft until timing marks is visible through the ventilation plug hole.
c. Establish that the magneto is at the number one
firing position. It is possible for the timing mark to
be visible while firing position is 180 degrees from
number one firing position.

d. If timing pin is not used, keep timing mark centered in ventilating plug hole during magneto installation.
e. Be sure magneto gasket (right magneto), magneto adapter and gaskets (left magneto) are in place
and that the engine is in the correct firing position,
then install magneto(s) approximately at the angle
noted during removal, tighten mounting nuts finger
tight.
NOTE
Remove timing pin (or nail) from magneto, if
installed. Be sure to remove this pin before
rotating propeller.
f. Connect a timing light to the capacitor (primary
lead) terminal at the rear of the magneto and to a
good ground.
g. Rotate propeller opposite to normal direction of
rotation a few degrees (approximately 5 degrees) to
close magneto contact points.

NOTE

It is necessary to "spark" the magneto to
establish the correct firing position. The outlet plate with the spark plug leads must be installed. Hold number one spark plug lead (see
figure 12A-4) close to magneto case, or ground
the magneto and hold the number one spark plug
lead close to a good ground. Rotate impulse
coupling (left magneto) or drive coupling (right
magneto) in normal direction of rotation until
a spark occurs at this lead. (Impulse coupling
pawls must be depressed to turn magneto shaft
in normal direction of rotation. ) Turn coupling
or drive coupling backwards a few degrees, until timing mark is centered in ventilating plug
hole and install timing pin (or 0. 096 inch 6penny nail) through hole in bottom of magneto
next to flange and into mating hole in the rotor
shaft. This locks the magneto approximately
in firing position while installing on the engine.

Do not rotate propeller back far enough to
engage impulse coupling, or propeller will
have to be rotated in normal direction of
rotation until impulse coupling releases, then
again backed up to a few degrees before the
firing position.
h. Slowly advance propeller (tap forward with
minute movements as firing position is approached)
in normal direction of rotation until timing light indicates position at which contacts break. The contacts
should break at the advanced firing position of number one cylinder. Loosen mounting nuts slightly and
rotate magneto case to cause the contacts to break at
the correct position. Tighten mounting nuts.
i. After tightening magneto mounting nuts, recheck
timing. Make sure both magnetos are set to fire at
the same time. Remove timing equipment, install
spark plugs, and connect spark plug leads and ignition switch leads.

NO. 1
OUTLET

TIMING MARK

T
VIEW

VIEW A-A

LOOKING
FORWARD
Figure 12A-4.

No. 1 Magneto Outlet
12A-15

NOTE

NOTE
Beginning with the number one outlet, the magneto fires at each successive outlet in a counterclockwise direction, looking at the outlets. Connect number one magneto outlet to number one
cylinder spark plug lead, number two outlet to
the next cylinder to fire, etc. Engine firing
order is listed in paragraph 12A-8.
12A-48. MAINTENANCE. Magneto-to-engine timing
should be checked at the first 50 hours, first 100
hours, and thereafter at each 200 hours. If timing to
the engine is not within plus zero degrees and minus
two degrees, the magneto should be retimed to the

engine.
NOTE
If ignition trouble should develop, spark plugs
and ignition wiring should be checked first. If
the trouble appears definitely to be associated
with a magneto, the following may be used to
help disclose the source of trouble.
a. Remove high-tension outlet plate and check distributor block for moisture.
b. If any moisture is evident, lightly wipe with a
soft, dry, clean, lint-free cloth. Install outlet plate.
NOTE
Since these magnetos MUST NOT BE DISASSEMBLED, a new magneto should be installed if the
moisture check does not remedy the trouble.
12A-49. SPARK PLUGS. Two 18-mm spark plugs
are installed in each cylinder and screw into helicoil type thread inserts. The spark plugs are
shielded to prevent spark plug noise in the radios and
have an internal resistor to provide longer terminal
life. Spark plug life will vary with operating conditions. A spark plug that is kept clean and properly
gapped will give better and longer service than one
that is allowed to collect lead deposits and is improperly gapped. The correct gap setting is given in
paragraph 12A-8.

Some controls have intricate parts that will
fall out and possibly be lost if the control is
pulled from the housing while the control is
disconnected.
12A-52. RIGGING. When adjusting any engine control, it is important to check that the control slides
smoothly throughout its full range of travel, that it
locks securely if equipped with a locking device, and
the arm or lever it operates moves through its full
arc of travel.
CAUTION
Whenever engine controls are being disconnected,-pay-particular attention to the exact
position, size and number of attaching washers
and spacers. Be sure to install attaching parts
as noted when connecting controls.
12A-53.

THROTTLE CONTROL.

NOTE
Before rigging throttle control shown in figure
12A-5, check that staked connection (4) between rigid conduit (2) and flexible conduit (3)
is secure. If any indication of looseness or
breakage is apparent, replace the throttle
control before continuing with the rigging.
a. Pull throttle control out (idle position) and remove throttle control knob (1).
b. Screw jam nut (7) all the way down (clockwise)
and install throttle knob. Screw the knob securely
against the jam nut. Do not back jam nut out. This
will prevent bottoming and possible damage to the
staked connection.
c. Disconnect throttle control at the carburetor
throttle arm, push throttle control in until jam nut
hits friction lock (6) while the friction lock is loose,

NOTE
At each 100-hour inspection, remove, clean,
inspect, and regap all spark plugs. Install
lower spark plugs in upper portion of cylinders and install upper spark plugs in lower
portion of cylinders at each 100-hour inspection. Since deterioration of lower spark
plugs is usually more rapid than that of the
upper plugs, rotating helps prolong spark
plug life.
12A-50.

ENGINE CONTROLS.

12A-51. Engine controls of the push-pull type include the throttle, mixture, and carburetor heat control. The engine controls are equipped with positionlocking devices which prevent vibration-induced
"creeping" of the controls.
12A- 16

1. Knob
2. Rigid Conduit
3. Flexible Conduit
4. Staked Connection
Figure 12A-5.

5.
6.
7.

Instrument Panel
Friction Lock
Jam Nut

Throttle Control

then pull control out approximately 1/8 inch for cushion. Note position of large washer at carburetor end
of control. Install washer in same position when
connecting control to arm.
d. Tighten friction lock (6), being careful not to
change position of the throttle.
e. Move throttle arm on carburetor to full open,
adjust rod end at end of throttle control to fit, and
connect to arm on carburetor.
f. Release friction lock and check full travel of
arm on carburetor. If further adjustment is required,
make all adjustment at the carburetor end of control.
DO NOT change jam nut (7) setting.
g. Tighten rod end locknuts at carburetor end of
control. Be sure to maintain sufficient thread engagement between rod end and control.

12A-55. CARBURETOR HEAT CONTROL.
a. Loosen clamp securing the control to the bracket
on engine.
b. Push control full in, then pull it out approximately 1/8 inch from panel for cushion.
c. Shift control housing in its clamp so that the
valve in the airbox is seated in the full open position.
Tighten clamp in this position.
d. Pull out on the control and check that the air
valve inside the airbox seats in the opposite direction.
e. Check that bolt and nut on the air valve lever
secures the control wire and that the bolt will swivel
in the lever.
f. Bend the wire tip 90 degrees to prevent it from
being withdrawn if the attaching nut should become
loose.

12A-54. MIXTURE CONTROL.
a. Push mixture control full in, unlock then pull it
out approximately 1/8 inch for cushion.
b. Loosen clamp securing the control to the engine.
c. Shift control housing in the clamp so that the
mixture arm on the carburetor is in the full open
(RICH). Tighten the clamp in this position.
d. Unlock and pull mixture control full out. Check
that idle mixture arm on carburetor is full closed
(IDLE CUT-OFF).
e. Check that the bolt and nut at the mixture arm
on carburetor secures the control wire and that the
bolt will swivel in the arm.
f. Bend the wire tip 90 degrees to prevent it from
being withdrawn if the attaching nut should become
loose.
g. When installing a new control, it may be necessary to shorten the wire and/or control housing.
h. The mixture arm on the carburetor must contact
the stops in each direction, and the control should
have approximately 1/8 inch cushion when pushed full
in.

12A-56.

12A-58.

STARTING SYSTEM.

12A-57. The starting system employs an electric
starter motor mounted at the front (propeller end)
lower left side of the engine. A starter solenoid is
activated by the ignition key on the instrument panel.
When the solenoid is activated, its contacts close
and electrical current energizes the starter motor.
Initial rotation of the starter armature shaft, engaged
with the reduction gear, drives the Bendix shaft and
pinion. When the armature turns the reduction gear,
the Bendix drive pinion meshes with the crankshaft
ring gear assembly by inertia and action of the screw
threads within the Bendix sleeve. A detent pin engages in a notch in the screw threads which prevents
demeshing if the engine fails to start when the starting circuit is de-energized. When the engine reaches
a predetermined speed, centrifugal action forces the
detent pin out of the notch in the screw shaft and
allows the pinion to demesh from the ring gear.

TROUBLE SHOOTING STARTER SYSTEM.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

STARTER WILL NOT OPERATE.
Defective master switch
or circuit.

Check master circuit.

Repair circuit.

Defective starter switch
or switch circuit.

Check switch circuit continuity.

Replace switch or wires.

Defective starter.

Check through items above. If
another cause is not apparent,
starter is defective.

Remove and repair or replace
starter.

STARTER MOTOR RUNS, BUT DOES NOT TURN CRANKSHAFT.
Defective Bendix drive.

Remove starter and check Bendix
drive.

Replace defective parts.

Damaged starter pinion
gear or ring gear.

Remove starter and check pinion
gear and ring gear.

Replace defective parts.

12A-17

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

STARTER DRAGS.
Low battery.

Check battery.

Charge or replace battery.

Starter switch or relay
contacts burned or dirty.

Replace with serviceable unit.

Defective starter power
cable.

Check cable.

Replace cable.

Defective starter.

Check starter brushes, brush
spring tension, thrown solder
on brush cover.

Repair or replace starter.

Dirty, worn commutator.

Clean, check visually.

Turn down commutator.

Worn starter pinion.

Remove and examine pinion.

Replace starter drive.

Worn or broken teeth on
ring gear.

Rotate propeller to examine
ring gear.

Replace ring gear.

STARTER EXCESSIVELY NOISY.

12A-59. REMOVAL AND INSTALLATION.
a. Remove engine cowling as required for access.
b. Disconnect electrical cable at starter motor,
Insulate the disconnected cable terminal as a safety
precaution.
c. Remove three nuts and washers and one bolt
securing starter to crankshaft. Work starter from
engine.
d. To install starter, position starter on mounting
pad aligning dowel pins in starter mounting pad with
holes in mounting pad on engine.
e. Secure starter with washer, lockwasher and nut,
three places, and install bolt and washers.
f. Tighten nuts and bolt evenly to a torque value of
150 Ib-in.
g. Connect electrical cable to starter terminal and
install engine cowling.
12A-60. PRIMARY MAINTENANCE of the starter
includes replacing brushes and brush springs, cleaning dirty commutator and turning down burned or outof-round commutator.
NOTE
No lubrication is required on the starter motor
except at overhaul. Never lubricate the commutator. For overhaul of the starter, refer
to the manufacturer's service publications.
Starter brushes should be replaced when worn to onehalf or less of their original length (compare with a
new brush). Brush spring tension should be sufficient
to hold brush in form contact with the commutator.
Brush leads should be unbroken, with their terminal
screws tight. A glazed or dirty commutator can be
cleaned by holding a strip of No. 00 or No. 000 sandpaper or a brush seating stone against it. Move the
12A-18

sandpaper or stone back and forth across the commutator to avoid wearing a groove. Do not use emery
paper or carborundum because of their possible
shorting action.
CAUTION
Never operate the starting motor more than
12 seconds at a time without allowing it to
cool.
Roughness, out-of-roundness, or high mica may
necessitate turning down the commutator. After the
turning operation, the mica should be undercut.
Blow out all dust after the commutator is cleaned.
12A-61. EXHAUST SYSTEM. The exhaust system
consists of an exhaust pipe from each cylinder to the
muffler located beneath the engine. The muffler
assembly is enclosed in a shroud which captures exhaust heat that is used to heat the aircraft cabin. A
shroud on number three exhaust pipe is used to capture heat for carburetor heat at the engine intake
system. The tailpipe welded to the muffler routes
exhaust gases overboard.
12A-62. REMOVAL.
a. Remove engine cowling for access.
b. Disconnect flexible ducts from shrouds on muffler assembly and exhaust pipe.
c. Remove nuts, bolts, washers, and clamps
attaching exhaust pipes to muffler assembly.
d. Loosen nuts attaching exhaust pipes to the cylinders and remove muffler assembly.
e. Remove nuts and washers attaching exhaust
pipes to the cylinders and remove pipes and gaskets.

CLAMP

MUFFLER

SHROUD
(CARBURETOR
HEAT)

TAILPIPE

EXHAUST PIPE

SHROUD

Figure 12A-6.

Exhaust System
12A-19

12A-63. INSPECTION of the exhaust system should
.be thorough because the cabin heating system uses
air heated by the heat exchanger of the exhaust syster. Since exhaust systems of this type are subject
to burning, cracking, and general deterioration from
alternate thermal stress and vibrations (comparable
to those affecting automotive mufflers), inspection is
important and should be accomplished every 100
hours of operation. In addition, an inspection should
be performed anytime exhaust fumes are detected in
the cabin.
a. Remove engine cowling, and loosen or remove
heating shrouds so that ALL surfaces of the exhaust
system can be visually inspected. Especially check
areas adjacent to welds. Look for exhaust gas deposits in surrounding areas, indicating that exhaust
gas is escaping through a crack or hole.
b. For a more thorough-inspection, or-if-exhaustfumes have been detected in the cabin, the following
procedure is recommended:
1. Remove exhaust pipes and mufflers. Re-move all shrouds.
2. Use rubber expansion plugs to seal openings.
3. Using a manometer or gage, apply approximately 1-1/2 psig (3 inches of mercury) air pressure
while the muffler and each exhaust pipe is submerged
in water. Any leaks will appear as bubbles and can
be readily detected.
4. It is recommended that any exhaust pipe or
muffler found defective be replaced with a new part
before the next flight.
c. Reinstall exhaust system.
12A-64. INSTALLATION. Reverse procedure outlined in paragraph 12A-62 to install exhaust system.
Be sure there is one new copper-asbestos gasket
between each exhaust pipe and its mounting pad on
the cylinder. When installng attaching nuts, install
*plain washer, internal tooth washer and nut. Make
sure clamps attaching muffler to exhaust pipes are
tight and all air ducts are installed.
12A-65.

EXTREME WEATHER MAINTENANCE.

12A-66. COLD WEATHER. Cold weather starting
is made easier by the installation of the engine
primer system. The primer system is a manually
operated type. Fuel is supplied by a line from the
fuel strainer to the plunger type primer. Operating
the primer forces fuel to the engine. Fuel is
delivered to the intake valve port of the cylinder.
Primer lines should be replaced when crushed or
broken, and should be properly clamped to prevent
vibration and chafing. With an external power receptacle installed, an external power source may be
connected to assist in cold weather or low battery
starting. Refer to paragraph 12A-67 for use of the
external power receptacle.
The following may also be used to assist engine
starting in extreme cold weather. After the last
flight of the day, drain the engine oil into a clean
container so the oil can be preheated. Cover the
engine to prevent ice or snow from collecting inside
the cowling. When preparing the aircraft for flight
or engine run-up after these conditions have been
followed, preheat the drained oil.
.A-20

WARNING
Do not heat the oil above 121°C (250°F). A
flash fire may result. Before pulling the propeller through, ascertain that the magneto
switch is in the OFF position to prevent accidental firing of the engine.
After preheating the oil, gasoline may be mixed with
the heated oil in a ratio of 1 part gasoline to 12 parts
oil before pouring into the engine oil sump. If the
free air temperature is below -29°C (-20°F), the engine compartment should be preheated by a ground
heater. After the engine compartment has been preheated, inspect all engine drain and vent lines for
presence of ice. After this procedure has been complied with, pull the propeller through several revolutionsbyhand-beforestarting engine.
CAUTION
Due to the desludging effect of the diluted oil,
engine operation should be observed closely
during the initial warm-up of the engine. Engines that have considerable amount of operational hours accumulated since their last dilution period may be seriously affected by the
dilution process. This will be caused by the
diluted oil dislodging sludge and carbon deposits within the engine. This residue will
collect in the oil sump and possibly clog the
screened inlet to the oil pump. Small deposits
may actually enter the oil pump and be trapped
by the main oil filter screen. Partial or complete loss of engine lubrication may result
from either condition. If these conditions are
anticipated after oil dilution, the engine should
be run for several minutes at normal operating temperatures and then stopped and inspected for evidence of sludge and carbon deposits in the oil sump and oil filter screen.
Future occurrence of this condition can be
prevented by diluting the oil prior to each oil
change. This will prevent the accumulation
of the sludge and carbon deposits.
12A-67. GROUND SERVICE RECEPTACLE. With
the ground service receptacle installed, the use of an
external power source is recommended for cold
weather starting and lengthy maintenance of the aircraft electrical system with the exception of electronic equipment on the Skyhawk.
NOTE
On the Standard Model 1721, power is supplied
to all electrical and electronic circuits from a
single bus bar. On Skyhawk models, electrical
power is supplied through a split bus bar, one
side containing electronic system circuits, and
the other side having general electrical system
circuits. In the split bus system, both sides of
the bus are on at all times except when either an
external power source is connected or the starter switch is turned on; then a power contactor
Is automatically activated to open the circuit to

the electronic bus. Isolating the electronic circults in this manner prevents harmful transient
voltages from damaging the semi-conducters in
the electronic equipment.

when the engine is hot. If it occurs, repeat the start
ing procedure with the throttle approximately onehalf OPEN, and the mixture control in IDLE CUTOFF. As the engine fires, move mixture control to
full RICH and decrease the throttle setting to desired

idling speed.
The ground service plug receptacle circuit incorporates a polarity reversal protection. Power from
the external power source will flow only if the ground
service plug is correctly connected to the aircraft.
If the plug is accidentally connected backwards, no
power will flow to the aircraft electrical system,
thereby preventing any damage to electrical equipment.

Engine mis-starts characterized by sufficient power
to disengage the starter but dying after three to five
revolutions are the result of an excessively lean mixture after the start. This can occur in either warm
or cold temperatures. Repeat the starting procedure
with additional priming.

CAUTION|
The battery and external power circuits have been
designed to completely eliminate the need to "jumper"
across the battery contactors to close it. A special
fused circuit in the external power system supplies
the needed "jumper" across the contacts so that with
a "dead" battery and an external power source applied,
turning the master switch ON will close the battery
contactor.
12A-68. HOT WEATHER. Engine starting in hot
weather or with a hot engine is sometimes hampered
by vapor formation at certain points in the fuel sysTo purge the vapor, remove the carburetor
ter.
vent plug and purge the carburetor and lines by turning the fuel selector valve on. Purge the carburetor
in this manner until fuel stands level with the vent
plug opening. Replace the carburetor vent plug and
operate the engine to make sure that the condition
has been corrected.
Engine mis-starts characterized by weak intermittent
explosions followed by puffs of black smoke from the
exhaust are caused by over-priming or flooding. This
situation is more apt to develop in hot weather, or

Never operate the starting motor more than
12 seconds at a time. Allow starter motor to
cool between cranking periods to avoid overheating. Longer cranking periods will shorten
the life of the starter motor.
12A-69. DUSTY CONDITIONS. Dust induced into
the intake system of the engine is probably the greatest single cause of early engine wear. When operating under high dust conditions, service the induction
air filter daily as outlined in Section 2 of this Supplement and in the Service Manual. Also, change engine oil and lubricate the airframe more often than
specified.
12A-70. SEACOAST AND HUMID AREAS. In salt
water areas, special care should be taken to keep the
engine and accessories clean to prevent oxidation.
In humid areas, fuel and oil should be checked frequently and drained on condensed moisture.
12A-71. HAND CRANKING. A normal hand cranking procedure may be used to start the engine.

SHOP NOTES:

12A-21/12A-22

SECTION 13

~~~FUEL
0I^^~~~

SYSTEMS

TABLE OF CONTENTS

Page

FUEL SYSTEMS ........
Trouble Shooting (Except Model 185) . .
Trouble Shooting (Model 185) ......
FUEL CELLS - MODELS 180, 182, AND 185
General Precautions .
.........
Fuel Cell Removal and Installation . ...
Fuel Cell Preservation ........
.
FUEL CELL REPAIRS ..........
U.S. Rubber - US-907N and US-943 Cells.
U.S. Rubber - US-932 Cells. ......
Fuel Cell Testing - U.S. Rubber ....
Goodyear - BTC 37 and BTC 39 Cells ..
Fuel Cell Testing - Goodyear .
.....
Fuel Tank Replacement - Models 150,
172, and P172
.
........
.
Replacement of Fuel Gage Transmitters .
Checking Fuel Vent ...
.....
.
Fuel Selector Valve Replacement (Models
P172, 180, 185, and Prior to 172F)
.
Fuel Selector Valve Replacement (Model
182 and Model 172F and On) .....
Fuel Shut-Off Valve Replacement
(Model 150) .............

13-1.

13-1
13-1
13-6
13-18
13-18
13-18
13-20
13-20
13-20
13-21
13-22
13-23
13-24
13-26
13-27
13-27
13-27
13-27
13-27

Fuel Shut-Off Valve Replacement
(Model 185) .............
Selector Valve and Shut-Off Valve Repair.
Fuel Strainer Replacement and Cleaning .
Fuel Strainer Drain .
.........
Primer Systems
.........
ELECTRIC AUXILIARY FUEL PUMP. .
.
Disassembly
.
.........
.
Disassembly of Motor .
.......
Inspection of Motor Components .....
Reassembly of Motor
.........
Disassembly of Pump .
......
.
Inspection of Pump Components .....
Reassembly of Pump .
......
.
Disassembly of Bypass and Pressure
Relief .....
.........
Inspection of Bypass and Pressure Relief.
Reassembly of Bypass and Pressure
Relief .
.
..........
.
Adjusting Pressure Relief ......
Functional Test Procedure .......
ELECTRIC FUEL PUMP CIRCUIT .....
Rigging Throttle-Operated Switch ...

13-35
13-35
13-35
13-35
13-35
13-36
13-37

WARNING

FUEL SYSTEMS.

13-2. Fuel systems for the different models are
shown in the schematic diagrams beginning with
Figure 13-1. Details of the various systems are
shown in succeeding illustrations. The Model 185
fuel system differs from that of the other Cessna
models to meet engine fuel injection requirements.
13-3.

13-27
13-30
13-30
13-30
13-33
13-33
13-35
13-35
13-35
13-35
13-35
13-35
13-35

Fuel draining from fuel tanks and disconnected lines or hoses constitutes a fire hazard.
Adequate safety precautions should be taken
whenever it is necessary to drain fuel or to
disconnect lines or hoses.

TROUBLE SHOOTING (Except Model 185).
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

NO FUEL TO CARBURETOR
Fuel selector valve or shut-off
valve not turned on.

Check position of valve.

Turn on.

Fuel tanks empty.

Check fuel quantity.

Service with proper grade and
amount of fuel.

Fuel line disconnected or
broken.

Inspect fuel lines.

Connect or repair fuel lines.

Inlet elbow or inlet screen in
carburetor plugged.

Disconnect fuel line at carburetor, remove elbow and screen
and inspect.

Clean and/or replace.

Fuel tank outlet screens
plugged.

Disconnect fuel lines from tank
outlets. No flow indicates
plugged screens.

Remove and clean screens and
flush out fuel tanks.

13-1

FUEL QUANTITY INDICATORS
LEFT

VENT

CHECK
VALVE

RIGHT

FILLER
CAP

LEFT WING TANK

RIGHT WING TANK

QUANTITY
TRANSMITTERS
FUEL SCREEN

FUEL SCREEN
FUEL TAFUEL
DRAIN PLUG

TANK SUMP
DRAIN PLUG

FUEL SELECTOR
VALVE
FUEL LINE
DRAIN PLUG

ENGINE PRIMER

FUEL STRAINER

STRAINER

THROTTLE

CARBURETOR

MIXTURE
CONTROL
KNOB
TO ENGINE
CYLINDERS
THRU 1967 MODELS

NOTE
On the Model 150, the fuel lines from the
tanks are connected to a tee, and a single line
is routed from the tee to a fuel shut-off valve,
used instead of a selector valve.
Not all aircraft use the strainer drain control.
Optional quick-drain valves may be used in-

CODE
VENT

-.-

FUEL
MECHANICAL LINKAGE
CONNECTION

Figure 13-1.

Fuel System Schematic - Models 150, 172, and P172 (Sheet 1 of 3)
13-3

ISOLATION PROCEDURE

PROBABLE CAUSE

REMEDY

NO FUEL TO CARBURETOR (Cont).
Defective fuel selector valve
or shut-off valve.

Disconnect outlet and inlet lines
from valve. If fuel flows from
inlet line but not through valve, it
is defective.

Remove and repair or replace
valve.

Plugged fuel strainer.

Inspect strainer.

Remove and clean strainer and
screen.

Fuel line plugged.

Starting at the carburetor, disconnect fuel lines successively until
plugged line is located.

Clean out or replace fuel line.

NOTE
To preclude possible leaks at fuel tank filler necks (the type that screws into the
adapter plate inside the tank), fill the cavity immediately surrounding the threads
with Parker Sealube (or equivalent).
FUEL STARVATION AFTER STARTING.
Partial fuel flow from the
preceding causes.

Use the preceding isolation procedures, checking for sufficient
rate of flow.

Use the preceding remedies.

Plugged fuel vent.

Check per paragraph 13-18.

See paragraph 13-18.

Water in fuel.

Open fuel strainer drain valve
and check for water.

Drain fuel tank sumps, fuel lines,
and fuel strainer.

Fuel tanks empty.

Check fuel quantity.

Service with proper grade and
amount of fuel

Circuit breaker open or defective, or blown fuse.

Check visually; check continuity
if circuit breaker is not open.

Reset circuit breaker; replace
blown fuse or defective circuit
breaker.

Loose connections or open

Check connections and wiring.

Tighten connections; repair or

NO FUEL QUANTITY INDICATION.

replace wiring.

circuit.

Defective fuel quantity indicator or transmitter. (Also
see paragraphs 16-47 thru
16-49.)

Disconnect wire from transmitter
at indicator not reading. Install
jumper wire from good indicator
(corresponding terminal) to indicator not reading. If indicator
does not register, it is defective;
if it does, transmitter is faulty.

Replace defective indicator or
transmitter.

Check per paragraph 13-18.

See paragraph 13-18.

PRESSURIZED FUEL TANK.
Plugged bleed hole in fuel vent.

-3-2

FUEL QUANTITY INDICATORS
FUlL

LET

LEFT
WING

FUEL

TRI»MT

FILLER CA

FUEL QUANTITY

FILLER CAP

RIGHT

WING

TANK

CROSSOVER

VENT

VENTSCREEN --

FUEL TANK SUMP
DRAIN PLUG

SCREEN

FUEL TANK SUMP
DRAIN PLUG

CONTROL

-MECHANICAL LINKAGE

1968 MODEL 150H

ELECTRICAL
CONNECTION

Figure 13-1.
13-4

Fuel System Schematic - Model 150 (Sheet 2 of 3)

TANK

FUEL QUANTITY INDICATORS
R. FUEL

LEFT
WING TANK

FILLER CAP

VENT

/---

RIGHT
WING TANK

VENT

CROSSOVER.

FILLER CAP

FUEL QUANTITY
TRANSMITTERS

VENT
SCREEN

SCREEN-

FUEL TANK SUMP
DRAIN PLUG

FUEL

SELECTOR
VALVE

ENGINE
PRIMER

STAINERSTRAINER

CONTROE-- 0 (

FUEL SUPPLY
..... '

VENT
LISKMECHANICAL
LINKAGE
ELECTRICAL
CONNECTION

Figure 13-1.

---

}

THROTTLE

CARBURETOR

TO ENGINE
CYLINDERS
1968 MODEL 1721

Fuel System Schematic - Model 172 (Sheet 3 of 3)
13-4A

FUEL QUANTITY INDICATORS

Model 182 system prior to serial No. 18255786 is
identical, except that the vent and check valve are

CODE

182 system beginning with the serial noted, as well
as prior serials on which the later system has been

VENT

installed.

MECHANICAL
ELECTRICAL
CONNECTION

Figure 13-2.
13-4B

Fuel System Schematic - Models 180 & 182 (Sheet 1 of 2)

FUEL
LEFT

ago|

QUANTITY INDICATORS
ark'

RIGHT

13-4.

TROUBLE SHOOTING (Model 185).
NOTE
This trouble shooting chart should be used in conjunction
with the engine trouble shooting chart in Section 12.

REMEDY

ISOLATION PROCEDURE

PROBABLE CAUSE

NO FUEL FLOW TO ENGINE-DRIVEN FUEL PUMP.
Fuel shut-off valve not turned

Check position of valve.

Turn fuel shut-off valve on.

Fuel tanks empty.

Check fuel quantity.

Service with proper grade and
amount of fuel.

Fuel line disconnected or broken.

Inspect fuel lines.

Connect or repair fuel lines.

Fuel cell outlet screens plugged.

Disconnect fuel lines from cell
outlets. No flow indicates
plugged screens.

Remove and clean screens and flush
out fuel cells.

Defective fuel selector valve.

Disconnect inlet and outlet lines
from valve. If fuel flows from
inlet line but not through valve.
it is defective.

Remove and repair or replace
selector valve.

Plugged fuel strainer.

Inspect strainer.

Clean strainer and screen.

Defective check valve in
electric fuel pump.

Disconnect inlet and outlet lines
from fuel pump. If fuel flows
from inlet line but not through
pump, it is defective.

Repair or replace electric pump.

Fuel line plugged.

Starting at fuel pump inlet, disconnect fuel lines successively
until plugged line is located.

Clean out or replace luel line.

FUEL STARVATION AFTER STARTING.
Partial fuel flow from the preceding causes.

Use the preceding isolation procedures, checking for sufficient
rate of flow.

Use the preceding remedies.

Malfunction of engine-driven fuel
pump or fuel injection system.

Refer to Section 12.

Fuel vents plugged.

Check per paragraph 13-18.

See paragraph 13-18.

Water in fuel.

Open fuel strainer drain valve
and check for water.

Drain fuel tank sumps, fuel lines.
and fuel strainer.

NO FUEL FLOW WHEN ELECTRIC PUMP IS TURNED ON.
Defective fuel pump switch.

Check continuity of switch.

Replace defective switch.

Defective throttle switch.

Check continuity of switch.

Replace defective switch.

Opcn or defective circuit
breaker.

Check visually; if not open.
check continuity.

Reset.

13-6

Replace if defective.

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

NO FUEL FLOW WHEN ELECTRIC PUMP IS TURNED ON. (Cont)
Loose connections or open
circuit.

Check connections and wiring.

Tighten connections; repair or
replace wiring.

Defective electric fuel pump.

Disconnect outlet line. With
proper fuel supply to pump, fuel
under pressure should flow
from outlet.

Replace defective pump.

Defective engine-driven fuel
pump by-pass or defective fuel
injection system.

Refer to Section 12.

Fuel tanks empty.

Check fuel quantity.

Service with proper grade and
amount of fuel.

Circuit breaker open or
defective.

Check visually; if not open, check Reset.
continuity.

Defective fuel quantity indicator
or transmitter. (Also see paragraphs 16-47 thru 16-49.)

Disconnect wire from transmitter Replace defective indicator or
at indicator not reading. Install transmitter.
jumper wire from good indicator
(corresponding terminal) to indicator not reading. If indicator
does not register, it is defective;
if it registers, transmitter is
defective.

Loose connections or open circuit.

Check connections and wiring.

NO FUEL QUANTITY INDICATION.

Replace if defective.

Tighten connections; repair or
replace wiring.

SHOP NOTES:

13-7

FUEL OUANTITY INDICATORS
H
LEFT fRG
- 1

LEFT
FUELTTANK
CHECK
VALVE

HCK
VALVE
VE

FILLER
CAP

FUEL OUANTITY TRANSMITTERS ?

VENT

FUEL TANK SUMP P,__|
DRAIN PLUG
RAINDRAIN

CAP
_

VENT

SCREENS

FUEL INE
DRAIN VALVE

FUEL TANK SUMP
PLUG
FUEL LINE
DRAIN
F
VALVE

'im

FUEL ACCUMOIL DILUTION
SWITCH (OPT)

RIGHT

FUE

IATOR TAN
5

S HU T O
ml
OIL
TJ ~~~~O
AK-"
SYSTEM 11
|_VALVE
^"-'iii-J--OIL DILUTION
l
..- .
SOLENOID VALVE (OPT
Sha
FUEL
13-85-TRAINER

..
I
FUEL SHUT-OFF

KNOB

FUEL STRAINER DRAIN KINOB

I~J~~ I
THROTTLE SWITCH~

I
"FUE
""
TPUM E SP
Sw i__H _"
EM/ERG O
6

IGNITION

SWITCH

ENGIPRIMER

!
TfgiBT
_
I

(OPT1

[

i//

-7

/^^

8 8

^ '

FILTER

|^W

~SCREEN

MIXTURE CONTROL KNOB

t]L

-iyFUItUNIT

lj _-\ J

_____

THROTTLE

ENGINE
FUEL
PUMP

ITO BUS BAR
^^.

^tf-si

ENTO
I NE

TAT

STARTER
I

_ _

,.FUEL

AIRTHROTTTHROTTLE
FUEL P

I
P"

FUEL FLOW
INDICATOR

DISTRIBUTORj

CODE
..... :7
|

susm1

FUEL SUPPLY
EXCESS FUEL
AND VAPOR
RETURN FUEL
MECHANICAL
LINKAGE
LItlNKAGE
|
ELECTRICAL
CONNECTION

Figure 13-3.
13-8

NOTE
.

FUEL NOZZLES
NOZZLES
FUEL

:.-.

Fuel tank sump drain plugs may be
replaced with optional quick-drain
valves
valves.

Fuel System Schematic-Model 185 Standard On-Off Valve

FUEL QUANTITY INDICATORS
LEFT
'
RIGHT

LEFT
FUEL TANK
CHECK FILLER
VALVE CAP

VALVE

VENT

VENT-

SELECTOR

......-..
-.....

CHECK
VALVE

SCREENS

SCREENS
FUEL TANK SUMP
DRAIN PLUG

FILLER
CAP

TRANSMITTERS-

FUEL QUANTITY

RIGHT
FUEL TANK

..---

FUEL LINE

FULNK SUMP
B..-«.--r PLUG
DRAIN

FUEL LINE

DRAIN VALVE

FUEL ACCUMOIL DILUTION

TA.i:.I
ULATORZi

SWITCH (OPT)

CHECK

VALVE
SdUr.OFF
VALVE

TO OIL
SYSTEM
OIL DILUTION
SOLENOID VALVE (OPT

2
i

=a
FUEL SHUT-OFF KNOB

J STRAINER
FUEL STRAINER

DRAIN KNOB

PUMP

THROTTLE SWITC

ENGINE

FUEL PUMP SWITCH--<

EMERG- r^--fn

0
IGNITION

STARTER
SWITCH

ENGINE
'^ggy

EMERG
0---O FF

PRIMER

ENGINE
FUEL

PU MP

SWITCH

BUS BAR

-^^

FILTER
SCREEN

MIXTURE CONTROL KNOB

FUEL UNIT
THROTTLE

:ir

AIRH\TE

AIR THROTTLE
FUEL
DISTRIBUTOR

|;1

FUEL FLOW
INDICATOR

CODE
FUEL SUPPLY
EXCESS FUEL
AND VAPOR

^,i"^
FUEL NOZZLES

RETURN FUEL

NOTE

MECHANICAL

INKAGE
ELECTRICAL
CONNECTION

Fuel tank sump drain plugs may be
Figure

14FeStShacMd

replaced with optional quick-drain
valves.
pvalves.

Figure 13-4. Fuel System Schematic -Model 185 Optional Selector Valve

13-9

OPTIONAL
FUEL SYSTEM
(on-off valve,
plus selector valve)

"
.'
i
"

.
ac"
..

---

.
'

./ .r

-A
...
-^^

R.
I
y Ye
/s----WASH ER

STANDARD FUEL SYSTEM
(on-off valve only)

~~~1 i.'
"'"- .....

;

*;-^:K
~,_^ :=-

;

:_^,.f..~,

Of;

$
1

\
^/Ct--..''
........ ^^^^

t
T^

t(I~L ANDLE
185-1301 & ON

22
PRIOR TO 150F

1.
2.
3.
4.
5.
6.
7.
8.

Finger Strainer
Line (Tank to Valve
Vent Line
Fuel Strainer
Hose
Line (Primer to Engine)
Hose
Vent Line (Crossover)
Figure 13-6.

9.
10.
11.
12.
13.
14.
15.

14
14

Line (Strainer to Primer)
Primer
Bolt
Unions
Tee
Shut-Off Valve
Nut

16.
17.
18.
19.
20.
21.
22.
23.

Lock Plate
Bolt
Drain Plug
Drain Line
Line (Tee to Strainer)
Elbow
Nut
Screw

Fuel System - Model 150 (Sheet 1 of 2)
13-11

top
24

26
150F & ON

Figure 13-6.
13-12

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.

Line (Valve to Drain Tee)
Line (Strainer to Primer)
Line (Primer to Engine)
Primer
Vent Line (Crossover)
Vent Line
Handle
Spacer
Shut-Off Valve
Line (Valve to Tee)
Line (Tee to Union)
Grommet
Line (Union to Tank)

14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.

Fuel system - Model 150 (Sheet 2 of 2)

Finger Strainer
Fuel Line Drain Tee
Lock Plate
Cap
Line (Drain Tee to Union)
Line (Union to Strainer)
Asbestos Grommet
Shield
Placard
Strainer Drain Control
Hose (Strainer to Engine)
Fuel Strainer
Fuel Strainer Drain Line

, I

i_2\MODE 1 72F1

1212s~~~~~~g22)
I
I1
4

~ \~

7It ...

WIs

~~~~~~~~

ii
~,.

11
,,

208~~~~~~D A
RU
gure 13-7.
7i

10,~-1
Fuel Ss

rsa.

22
" /
MODEL
172 PRIOR TO
DEL. 17223

^
SEE\}aFVGURE 13-14

13-13

.: Prime
St inger

-:;"^

rainr

Strainer

,5.
Baket
8. Shaft

Primer Line

24. Roll
Cap Pin
27.

SelectorUValve

19. pivot

7. Finger Strainer

15. Bracket

24. Cap

9Vent
ine()
16Hosent1S
9.

Vent
16. LineCrossver
Screw
17.
Nut

25. Placard
26; Drive

SEE FTGURE~13-14
1·

Figure 13-7.

21. Washer
pin
22.
Gu

Rose

2. FuelStrainer
274.

Hadle
Plte

0.27.

Fuel Sstemrainer1

Roll Pin

P172

13-13

"'*.

^'A

.^^

LE2

18051876 & ON

THRU 18051875

NOTE

Beginning with the Model 180G, extended vent tubes
are installed on all airplanes equipped with long range
fuel tanks. See figure 13-5 for long range tanks.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.

Vent Line (Crossover)
Aft Right Fuel Line
Aft Left FuelLine
Fuel Tank Vent Line
Fuel Line (Tee to Valve)
Forward Left Fuel Line
Selector Valve
Fuel Line (Valve to Strainer)
Fuel Strainer
Fuel Hose (Strainer to Engine)
Primer Line (Strainer to Primer)24.
Pme Line(Tee tin
tb Engie)
Primer Line (Primer to Tee)

Figure 13-8.
13-14

14.
15.
16.
17.
18.
19.
20.
21.
22.
23.

Primer
Forward Right Fuel Line
Cotter Pin
Handle
Plate
Cup
Bracket
Upper Shaft
Pivot
Spacer
Washer
25. P
26. LowerShaft

Fuel System - Model 180

,14

:
'...."
-^^^.:., "''*-- ^^^s.

18255845 & ON
A182-0001 & ON

.. .
"'*<"'/''^-.."'2

Figure 13-9. Fuel System - Model 182 (Sheet 1 of 2)
2s
(28).
assembly
2?"u
ngne
1.Af
Rgh Remove and replace it as a unit.

2'Ven Lie(rsoe)1 Pie in(SrinrtPim)21Sce
Beginning with the Model 182G, extended vent tubes
are installed on all airplanes equipped with long range
fuel tanks. See figure 13-5 for long range tanks.

13-15

1-1

See sheet 2 for the Model 182 system beginning with
serial No. 18255786, as well as prior serials on
which the later system has been installed.

1.
2.
3.
4.
5.
6.
7.
8.
9.

20.
10. Hose (Strainer to Engine)
Aft Right Fuel Line
21.
11. Primer Line (Strainer to Primer)
Vent Line (Crossover)
22.
12. Primer Line (Primer to Engine)
Aft Left Fuel Line
23.
13. Primer
Fuel Tank Vent Line
serials24.
s as pRightr Fuel
i Line
o r
well No.14.
18255786,
a Forward
Forward Left Fuel Lineserial
25.
15. Screw
Fuel Line (Tee to Valve)
26.
Fuel Line (Valve to Strainer) 16. Cotter Pin
27.
17. Handle
Drain Line
28.
18. Placard
Fuel Strainer
29.
19. Cup

Nut
Screw
Washer
Plug
13I1
Selector Valve on
Elbow
Cotter Pin
Coupling
Gear and Shaft Assembly
Spring Pin

NOTE
This fuel system is applicable to the Model 182, beginning
with serial No. 18255786, as well as prior serials on which
Service Kit No. SK182-38 (thru serial No. 18255785) or SK
..- 182-41 (thru serial No. 18256144) has been installed.

Y*..~
.o.°°"
f

~ '~'
.-,

Remaining components of the fuel system are the same as
those shown on sheet 1.
.........

FlFul
gre Sste
3-9

Fi gure 13-9.
13-16

ode8Set2of2

3>:

....

Fuel System - Model 182 (Sheet 2 of 2)

*'*^V^1

SERIAL
SERIAL
SERIAL
SERIAL

NO.
NO.
NO.
NO.

15063441 & ON
F150-0053 & ON
17254356 & ON
F172-0320 & ON

PRIOR TO SERIAL NO. 15063441
AND F150-0053

6
9

51~~;

PRIOR TO SERIAL NO. 17254356
AND F172-0320

1.
2.
3.

Access Cover
Cork Gasket
Ground Strap

4.
5.
6.
7.

Figure 13-9A.

MODELS 180, 182, AND 185

Wing Skin
Fuel Tank
Transmitter
Gasket

8.
9.
10.

Cork Washer
Washer
Wing Root Rib

Fuel Transmitter Grounding
13-17

13-5.

FUEL CELLS - MODELS 180, 182, AND 185.

13-6. These airplanes are equipped with rubberized
bladder-type fuel cells, one of which is located in the
inboard bay of each wing panel. The cells are
secured by snap fasteners to prevent collapse of the
flexible cells. The airplane may be equipped with
either Goodyear or U. S. Rubber Company fuel cells.
Goodyear and U. S. Rubber Company fuel cells are
interchangeable, therefore either type cell may be
used. Goodyear fuel cells are BTC-37, or BTC-39
type construction and U. S. Rubber Company fuel cells
may be either US-907N, US-943, or US-932 type
construction. Repair procedures for the fuel cells
differ for the type used. Therefore, determine which
fuelell-is-used-before-repairs-are-attempted. To
determine this, inspect the top outer surface of the
fuel cell. Each fuel cell is marked as to manufacturer and type of construction.
13-5. GENERAL PRECAUTIONS. When storing,
inspecting or handling Goodyear fuel cells, the following should be adhered to:
a. Fold cells smoothly and lightly as possible with
a minimum number of folds. Place protective wadding between folds.
b. Wrap cell in moisture-proof paper and place it
in a suitable container. Do not crowd cell in container, use wadding to prevent movement.
c. Stack boxed cells to allow access to oldest cells
first. Do not allow stacks to crush bottom boxes.
Leave cells in boxes until used.
d. Storage area must be cool, +30°F to +85°F, and
free of exposure to sunlight, dirt, and damage.
e. Used cells must be cleaned with soap and warm
water prior to storage. Dry and package as outlined in the preceding steps.
f. Do not carry cells by fittings. Maintain original
cell contours or folds when refolding for boxing.
13-8. FUEL CELL REMOVAL AND INSTALLATION.
When removing a fuel cell the following procedure is
suggested as a guide:
a. Drain applicable fuel cell by removing drain
plugs.
NOTE
Prior to removal of Goodyear fuel cells, drain
fuel, purge with fresh air, and swab out to remove all traces of fuel.
b. Remove wing root fairings and disconnect fuel
lines at wing root.
c. Remove clamps from forward and aft fuel cell
boss at wing root and carefully work fuel strainer
and line from cell boss.

d. Disconnect electrical lead and ground strap
from fuel quantity transmitter. Remove transmitter
by removing attaching screws and carefully work it
from fuel cell and wing rib.
e. Remove screws attaching drain adapter to lower
surface of wing.
f. Remove clamps attaching cross-over vent line
to fuel cells and work vent line out of cell being removed. In airplanes equipped with long range tank
(1964 and on), remove vent extension tube from inside the fuel cell. Vent extension tube is attached
to the crossover vent boss on the cell.
g. Remove clamps and work overboard vent line
from cell. Remove vent valve from inside of fuel
cell.
h. Remove fuel filler adapter and gaskets by removing screws attaching-adapter-to-wing-and-fuel
cell. On airplanes equipped with long range tanks,
remove cover plate and gaskets.
i. Working through filler neck opening, loosen
snap fasteners. Tilt snap fasteners slightly when
pulling cell free, to prevent tearing the rubber.
j. Collapse and carefully fold cell for removal,
then work cell out of fuel cell bay through filler
opening. Use care when removing and prevent
damage to cell
k. Unfold cell and remove fittings, snap fasteners
and fuel sump drain adapter.
To install a new or repaired fuel cell, proceed as
follows:
a. Cell compartment must be thoroughly cleaned
of all filings, trimmings, loose washers, bolts, nuts,
etc.
b. All sharp edges of cell compartments must be
rounded off and protective tape applied over all sharp
edges and protruding rivets.
c. Inspect cell compartment just prior to installation of a cell for the above mentioned conditions.
d. Install fuel drain adapter and snap fasteners.
e. Check to be sure cell is warm enough to be
flexible and fold as necessary to fit through fuel cell
access opening.
f. Place fuel cell in compartment, develop it out
to its full size and attach snap fasteners, then reverse the removal procedures for installation.
When fastening snap fasteners, tilt the fastener to
one side slightly to prevent placing a strain on the
rubber.
g. Install all new gaskets when installing fuel cell.
h. When tightening screw-type clamps, apply a
maximum of 20 pound-inches of torque to clamp
screws. No oil is to be applied to fittings prior to
installing.
i. When installing filler adapter, cover plate, and
fuel quantity transmitter to the wing and fuel cell,
tighten attaching screws evenly. The sealing or

References for Figure 13-10
1.
2.
3.
4.
5.
6.
7.
13-18

Screw
Cap
O-Ring
Adapter
Chain
Tank
Hanger

8. Clamp
9. Gasket
10. Plug
11. Strainer
12. Protector
13. Nut
14. Fuel Transmitter

15.
16.
17.
18.
19.
20.
21.

Ground Strap
Fitting
Line
Grommet
Hose
Valve
Cover Plate

STANDARD TANK

TANK DRAIN

Figure 13-10.

Fuel Cell Installation

Models 180, 182

and 185

913

13-19

SEE FIGURE 13-9A

1 14

tion.

compression surfaces must be assembled when
absolutely dry (NO SEALING PASTE TO BE USED).
j. After installation has been completed, cell
should be inspected for final fit within compartment,
making certain that cell is extended out to the
structure and no corners are folded in.
k. The final inspection prior to closing the cell
should be a close check to be sure cell is free of
foreign matter such as lint, dust, oil, or any installation equipment. If cell is not thoroughly clean,
it should be cleaned with a lint-free cloth soaked in
water, alcohol, or kerosene. NO OTHER SOLVENT
SHALL BE USED.

13-10.

FUEL CELL REPAIRS.

13-11.

U.S.

WARNING_
No repairs are to be made on the radius of a
cell or in the fitting area of a cell. No darnaged areas such as cuts and tears larger than
one inch are to be repaired in the field. Cells
with such damage should be replaced, or repaired by the manufacturer. Arrangements
for manufacturer to repair a fuel cell should
be made through Cessna.

NOTE
Throughout the airplane fuel system, from
the tanks to the engine-driven fuel pump or
carburetor, use Parker Sealube (or equivalent) as a thread lubricant or to seal a leaking
connection. Apply sparingly to male fittings
only, omitting the first two threads. Always
be sure that a compound, the residue from a
previously used compound, or any other
foreign material cannot enter the system.
Throughout the fuel injection system, from
the engine-driven fuel pump through the discharge nozzles, use only a fuel soluble lubricant, such as engine lubricating oil, on the
fitting threads. Do not use any other form
of thread compound on the injection system
fittings.
13-9. FUEL CELL PRESERVATION. The following
is a reprint of U. . Rubber Company directive:

"When synthetic rubber fuel cells are placed in ser-

vice, the gasoline has a tendency to extract the plasticizer from the inner liner of the cell. This extraction of plasticizer is not detrimental as long as gasoline remains in the fuel cells, as the gasoline itself
will act as a suitable plasticizer. When the gasoline

is drained from the fuel cell, the plasticizing effect

of the gasoline is lost and the inner liner of the cell
begins to dry out and subsequent cracking or checking will occur. This cracking or checking may penetrate through the inner liner permitting gasoline to
diffuse through walls of the cell after the cell has

been re-fueled. To prevent this failure, a thin coatIng of light engine oil should be applied to the inner
liner of all serviceable fuel cells, which have contained gasoline, when it is evident that the cells will
remain without fuel for more than ten days, whether
installed in airplanes or in storage. The oil will act

as a temporary plasticizer and will prevent the inner
liner from drying out and cracking. I it becomes
necessary to return the cell to the contractor or the
vendor for testing or repair, do not allow quantities
of oil to be puddled in the cell as it will make handling
and repair much more difficult. Cells should be repacked as similar to the original factory pack as
possible. "ing

13-20

RUBBER - US-907NANDUS-943CELLS.

OUTSIDE OF CELL:
-.- Use-a-piece-of-synthetic-rubbercoated fabric (U.
S. Rubber 5200 outside repair material) large enoughto cover damage at least 2" from cut in any direction.
Buff this material lightly and thoroughly with garnet
paperand wash with MethylEthylKetone (U.S. Rubber
Co. 3339 solution) to remove buffing dust.
b. Cement buffed side of patch with two coats of
U. S. Rubber Co. 3230 cement or Minnesota Mining
Co. EC-678. Allow each coat to dry 10-15 minutes.
c. Buff cell area to be patched lightly and thoroughly with garnet paper and wash with 3339 solution to
remove buffing dust.
d. Cement buffed area with two coats of U.S. Rubber
3230 or Minnesota Mining Co. EC-678 cement. Allow
each coat to dry 10-15 minutes.
e. Freshen cemented area of patch and cemented

area of cell with 3339 solution.

f. While still tacky, apply edge of patch to edge of
cemented area on the cell. With a roller or blunt
instrument, roll or press the patch to the cemented

area and roll or press it down a half-inch to an inch

across at a time so as not to trap air between patch
and cell. Lay 50 lb shot bag over patch which is
protected by piece of Holland Cloth to prevent sticking. Weight should not be removed for 6 hours.
g. Seal coat edge of patch 1/2" with one coat of

U.S.
S.

ubber 3230 or Minnesota Mining Co. EC-678

cement and allow the cement to dry thoroughly.

INSIDE OF CELL:
a. After the damaged area has been patched on the
outside of the cell and the repair allowed to stand a

minimum of 6 hours, the cell is then ready to have
the patch applied on the inside of the celL
b. Lightly and thoroughly buff a piece of cured
U. S. Rubber 5200/5187 nylon sandwich material
large enough to cover damage at least 2' from cut
in any direction. Wash buffing dust off patch with

Methyl Ethyl Ketone solution (U.S. Rubber 3339).
c. Cement buffed side of patch with two coats of
black rubber cement, U. S. Rubber 3230 or Minnesota Mining Co. EC-678, and allow each coat to
dry 10-15 minutes.
d. Buff cell area to be patched lightly and thoroughly with fine sandpaper (#"0") and then wash off buffdust with Methyl Ethyl Ketone solution (U. S.
Rubber 3339).
e. Coat buffed area with two coats of black rubber
cement, U.S. Rubber 3230 or Minnesota Mining Co.
EC-678, and allow each coat to dry 10-15 minutes.
f. Freshen cemented area of patch and cemented

area of cell with Methyl Ethyl Ketone (U. S. Rubber
\
contains all the necessary materials
3339) solution.
to repair a US-907N or a US-943 fuel cell.
g. While still tacky, apply edge of patch to edge of
This kit is available from the Cessna Service
cemented area, centering patch over cut in cell.
Parts Center.
With a roller or blunt instrument, roll or press the
patch to the cemented area on the cell. Hold part of
13-12. U. S. RUBBER - US-932 CELLS.
patch off the cemented area and roll or press it down
a half-inch to an inch across at a time so as not to
REPAIRS. All field repairs are to be made by FAA
trap air between patch and cell
Apply 50 lb shot
certificated repair stations using the Repair Kit RKbag to repaired area and do not disturb for 6 hours.
932 which is available from the Cessna Service Parts
h. Seal coat patch and 1/2" from edge of patch with
Center. Fuel cells should be pressure tested before
two coats of U. S. Rubber 3230 or Minnesota Mining
repair and 24 hours after repair using the procedure
Co. EC-678 cement. Allow the first coat to dry one
outlined in paragraph 13-13.
hour or more. Wipe patch and cemented area lightly
with #10 oil, so that when the cell is in its originalWARNING
position the patch area will not stick to other areas
of the cell.
No repairs are to be made on the radius of a
cell or in the fitting area of a cell. No damSCUFFED FABRIC:
aged areas such as cuts and tears larger than.
a. Buff area surrounding scuffed fabric,
one inch are to be repaired in the field. Cells
b. Wash buffing dust from area with 3339 solution,
with such damage should be replaced, or rec. Apply two coats of U. S. Rubber 3230 or Minnpaired by the manufacturer. Arrangements
esota Mining Co. EC-678 cement to the buffed area,
for manufacturer to repair a fuel cell should
allowing 10 minutes drying time between coats.
be made through Cessna.
NOTE
A fuel cell repair kit, U. S. Rubber Kit No.

KIT CONTENTS. Following is a list of materials
contained in the kit:

DESCRIPTION
3413 Patching Material
5356 Patching Material
Paint Brushes
3339 Solvent
Emery Cloth
Cheese Cloth
3420-A Adhesive
3420-B Adhesive
Spatula

QUANTITY
(one)
(one)
(five)
(one)
(five)
(one)
(five)
(five)
(five)

Piece Urethane Film 8" x 8"
Piece Urethane Nylon Fabric 8" x 8"
1/2" Commercial
1/2 Pint Can
Pieces 4 1/2" x 5 1/2" # 180 Grit
Piece 18" x 36"
1/2 Pint Cans, 32 Grams Each
Plastic Containers 2 Grams Each
Wooden

SHOP NOTES:

13-21

TYPES OF REPAIRS:
a. Use patches of Urethane film for small pin hole
type leaks.
b. Use fabric patches for tears or cuts up to 1"
long.
c. Patches may be applied to either the inside or
the outside surface of the fuel container, whichever
is more convenient.
d. Use a patch that will extend a minimum of 1" in
every direction beyond the area to be repaired.
MIXING INSTRUCTIONS FOR ADHESIVES.
a. Cut a small hole in the plastic container and pour
contents (3420-B) into the can containing the 3420-A.
b. Mix well with wood spatula (tongue depressor).
c.-Allowmixtureto stand for 10 minutes.
d. Mix again.
e. The mixed adhesive (3420) must be kept in a
closed container until used. Once this adhesive has
been mixed, it must be used within 12 hours.

13-13.

FUEL CELL TESTING - U.S. RUBBER.

PROCEDURE FOR PHENOLPHTHALEIN - AMMONIA
TESTING. When cells are removed from the airplane
for suspected leakage, the following method for locating leaks may be used. This method may also be
employed after local repairs have been made to check
both the efficiency of the repair and presence of other
leaks not originally found.
MATERIALS NEEDED:
a. Commercial or household ammonia (28-29%concentration).
b. Indicator solution -- contents per gallon as follows:
1. 1/2 gallon of distilled water.
2.1-/2 gallo-nof-denatured-alcohol;
3. 15 grams of phenolphthalein crystals or
powder.
c. Approximately three yards of balloon cloth or

airplane cloth.
PREPARATION FOR REPAIR.
a. Wash damaged area on fuel container with 3339
solvent. Surface must be clean and dry.
b. Buff area to be repaired with emery cloth and
wipe clean with a cheesecloth swab dampened in 3339
solvent. Buffed area should be larger than repair

PROCEDURE:
a. Pour ammonia on an absorbent cloth at the rate
of 3cc per cubic foot of cell capacity with a minimum
of 10 cc. Place saturated cloth inside cell
b. Close all openings and apply positive test air

patch.

pressure of 1/4 psi (4 ounces).

c. Buff and clean one side of repair patch as outlined in step "b".

CAUTION

d. Cement buffed surfaces of patch and article to
be repaired with two coats of mixed adhesive, allowing each coat to dry 10 minutes. Between adhesive
coat applications, brush may be kept in 3339 solvent.

Never inflate an unsupported cell above a
pressure of 1/4 psi (4 ounces). Pressures in
excess of four ounces may damage the cell.

PATCH APPLICATION.
a. Allow cemented surfaces to dry until tacky.
b. Center patch over damaged area and apply slowly, 1/2" to 1" at a tie,
makin sure no air is trapped
under the patch
c. Apply pressure by rubbing a well rounded screwdriver handle (or similar tool) across the patch.
d. Weight or clamp repaired area between two
pieces of wood (or metal) for a minimum of 8 hours
with waxed paper (or similar material) between the
repair and clamping blocks to prevent sticking. Avoid
sharp edges on clamping blocks or plates.

c. Soak cloth in phenolphthalein indicator solution.
d. Wring out cloth and spread evenly and smoothly
over area of cell being checked.
e. Check all surfaces of cell Leaks will be indicated by the appearance of pink spots on the cloth.

CAUTION
Do not disturb repair for 24 hours and repaired
container should be aged for 5 days at temperatures of 60*F to 80F before returning to
service,

SHOP NOTES:

13-22

PRECAUTIONS:
a. Extreme caution must be maintained to prevent
cover plates from damaging or cutting the cell during installation, phenol test, deflation and removal.
b. Unsupported test must be conducted on a flat,
dirt free surface having no sharp projections or anything which could damage the inflated cell An unsupported bladder cell can be inflated only to a pressure of 1/4 psi (4 ounces) maximum. Any pressure
in excess of this will cause damage or rupture of the
cell.
c. If phenolphthalein-ammonia solution is used more
than 8 hours a new solution should be prepared.

13-14. GOODYEAR BTC-37 OR BTC-39 CELLS. Recommended repair procedures for Goodyear fuel
cells are as follows:

Use Repair Kit No. 2F1-3-35342, which is available
from the Cessna Service Parts Center. Fuel cells
should be tested before and after repair using the
procedure outlined in paragraph 13-15

REPAIRS. All field repairs should be made on a
suitable size, well-lighted table, having a flat,
smooth, clean surface. Prevent contact with sharp
edges, corners, dirty floors or other surfaces. Repair area must be well ventilated.

No repairs are to be made on the radius of a
cell or in the fitting area of a cell. No damaged areas such as cuts and tears larger than

three inches are to be repaired in the field.
Cells with such damage should be replaced, or
repaired by the manufacturer. Arrangements
for manufacturer to repair a fuel cell should
be made through Cessna.

DO NOT PERMIT SMOKING OR OPEN FLAME
NEAR REPAIR AREA OR FUEL CELLS.

KIT CONTENTS. The following is a list of materials
contained in the repair kit:

QUANTITY

DESCRIPTION
*2331C Repair Cement
*2328C Cross-Linker
Methyl Ethyl Ketone
FT-160 Repair Fabric
Cellophane
Foam Rubber Cloth Back

(8)
(8)
(2)
(2)
(4)
(2)

(1/2 pint cans, 173 cc in each can)
(1 oz bottles, 28 cc in each bottle)
(1 pint cans)
(12" x 12" sheets)
(12" x 24" sheets)
(12" x 12" sheets)

*At room temperature, the shelf life of 2331C Repair Cement and 2328C Cross-Linker is six months
from date of packaging.
Additional equipment necessary to perform repairs
on Goodyear fuel cells are as follows:
QUANTITY

DESCRIPTION
Paint Brush
Roller
Aluminum Plates
Cure Iron

REPAIR LIMITATIONS.
a. Outside patches are to lap defect at least two and
one quarter inches in any direction from cut.
b. Inside patches are to lap defect at least two
inches in any direction from cut.
c. Outside patches are to be applied and cured prior
to applying an inside patch.
d. Blisters between innerliner and fabric larger
than one inch in diameter require an outside and an
inside patch.
e. Separations between outer plies larger than one
inch require an outside and inside patch. All holes
and punctures require an outside and inside patch.
f. Slits or tears up to three inches maximum length
require an outside and inside patch.
g. External abraided or scuffed areas without fabric
damage require an outside patch only.
h. A Icose lap may be trimmed provided that one
inch effective bond remains.

(1)
(1)
(2)
(1)

(1")
(1" diameter x 3/4" flat or equivalent)
(1/4" x 6" x 6")
(Goodyear Part No. 2F1-3-24721)

i. Air cure repair patches are to remain clamped
and undisturbed for 72 hours at room temperature of
approximately 75 degrees F.
PREPARATION FOR REPAIR.
a. Wash damaged area on fuel cell with Methyl
Ethyl Ketone, (MEK).
NOTE
When cleaning fuel cell, use a lint free cloth
dampened with MEK and clean an area of
approximately one square foot surrounding
the damaged area. A total of three separate
washings are recommended to assure cleanliness.
b. Cut a patch from repair material large enough to
cover damaged area by at least two and one quarter
13-23

inches in any direction from damage.
c. Taper edges and round corners of patch so as to
present a feather edge to the cell when patch is applied,
d. Abraid cell wall surface about injury and contact
side of patch with fine emery cloth to remove shine.
e. Repeat MEK washing two more times. A total
of three washings for each surface is required.
f. Tape a piece of cellophane inside cell over injury. This is done to prevent cell walls from becoming stuck together when applying cement and
patch.
g. When all of the preceding preparatory work has
been done and cell has been positioned on repair
table, mix cement as follows:
MIXING-ADHESIVES.-Mtx-repair-cement,2331C(1/2 pint can with 173 cc), with cross-linker 2328C,
(1 ounce bottle with 28 cc), and stir thoroughly.
NOTE
Mixing cement is done immediately prior to
use. The mixed cement has a pot life of 25
minutes after mixing. 2331C repair cement
requires thorough mixing to obtain full adhesive values.
Brush one even coat of mixed repair cement on the
cell wall around injury and on the contact side of repair patch. Allow this coat of cement to dry for
twenty minutes.
PATCH APPLICATION.
a. Repeat a second mixing of repair cement and
brush a second coat on the cell wall around injury and
on the contact side of repair patch.
CAUTION
Do not use first can of mixed cement for
second coat. Pot life of mixed cement is 25
minutes.
b. After the second coat of cement has been applied,
and ten minutes of drying time allowed, center repair patch over injury.
c. With a roller, roll or press patch to cemented
area of cell, starting at center of patch and working
to outside edge to prevent air from being trapped between patch and cell. Hold the unrolled portion of
repair patch off the cemented surface until roller
contact insures an air free union. At this time, repair patch may be moved on wet surface to improve
lap. Do not lift repair patch, slide it.
NOTE
Make sure cellophane inside cell over injury
remains in place as it will prevent the inside
surfaces of the cell being cemented together
when clamp is placed on patch.
d. Cover one surface of each of the aluminum plates
(plates must be larger than patch) with fabric-backed
airfoam, fabric side out. Tape airfoam in place.
Foam must cover edges of plate for protection.
13-24

e. Fold cell adjacent to patch and place prepared
plates, one over repair patch, and one on opposite.
f. Secure the assembly with a "C" clamp. Tighten
by hand. Check cement flow to determine pressure.
NOTE
Make sure that cell fold is not clamped between plates. This would cause a hard permanent crease. Also, make sure that patch
does not move as clamp is tightened.
g.

Leave cell clamped to air cure for 72 hours.
NOTE
Air-cure-repair sto be-madeat r.oomtempera ture of approximately 75°F. For each 10 degree drop in temperature add 25 per cent cure
time. Example: room temperature is 64 degrees, air cure for 90 hours instead of 72
hours.

h. After cure time has expired, remove clamp,
metal plate, foam rubber, and cellophane. To remove cellophane use a wet cloth or sponge to dampen
cellophane and remove by peeling off.
i. Inspect repair for any loose edges or unsatisfactory conditions: If a loose edge is found and it is
no more than 1/4 inch it is permissible to trim and
buff loose edge.
j. Inside patch is applied in the same manner as
the outside patch except for size of repair patch after
the outside patch has been cured.
NOTE
Success of applying an outside and inside re-pair
patch simultaneously is doubtful and not
recommended.
REPAIR PATCH - HEAT CURE METHOD. Follow
procedures for air cure method, except attach cure
iron to assembly during step "f", and plug electric
cord into electrical outlet.
NOTE
After two hours cure time with cure iron, unplug electric and allow repair iron to cool for
15 minutes. Then remove "C" clamp, plates
and cellophane. All heat cured patches are
ready for use when thoroughly cooled.
13-15. FUEL CELL TESTING - GOODYEAR. Fuel
cells should be tested after repair and before installation. Either of the following test procedures may
be used; however, the chemical test is the more
sensitive and preferred test.
SOAP SUDS TEST.
a. Install test plates on all fitting openings.
b. Inflate the cell with air to a pressure of 1/4 psi
(4 ounces) maximum.

WARNING

3.
5.
6.
4.
7.
2.
3.
4.
5.
6.
7.

Cap
Filler Neck
Pad
Gasket
Strap
Screw
Cap
Gasket
Filler Neck
Pad
Strap

FUEL TANKS WITH STEAM
METAL
.PURGE
FOR 30 MINUTES PRIOR TO REPAIR OF
TANKS.

10.
Adapter
12. Nut
13.
Gasket
11.
Valve
14.
9. Washer
Nut
Nut
10.
11.
Adapter
12. Washer
13. Gasket
14. Valve

17.
19.
20.
18.
21.
16.
17.
18.
19.
20.
21.

Nut
Gasket
Plug
Transmitter
Gasket
Washer
Nut
Transmitter
Gasket
Plug
Gasket
Figure 13-11.

15
14

valve
extends
for
at
top. Tube
andbe
forward
tank,
then
into
(14) must
ventNOTE
valve
slightly
Hingefuel
forupward.
extends
valve
for
must
be
at
top. forTube
vent valve (14)
Hinge
into fuel tank, then forward and
slightly upward.
Fuel Tank-

CAUTION
Never inflate an unsupported cell above a
pressure of 1/4 psi (4 ounces). Pressures
in excess of four ounces may damage the cell.
c. Apply a soap and water solution to all repaired
areas and all areas which are suspected of leakage.
Bubbles indicate leakage in the cell.
d. After completion of test, clean exterior of cell
and remove test plates.
CHEMICAL TEST.
a. Install test plate on all but one fitting opening.
b. Pour ammonia on an absorbent cloth in the
ratio of 3 cc per cubic foot of cell capacity.
c. Place the ammonia saturated cloth inside cell
and install test plate on opening,
d. Make a phenolphthalein solution as follows: Mix
40 grams of phenolphthalein crystals in 1/2 gallon
of ethyl alcohol. To this solution add 1/2 gallon of

Model 150

water.
e. Inflate the cell with air to a pressure of 1/4 psi
(4 ounces) maximum.
f. Soak a large white cloth in the phenolphthalein
solution.
g. Wring cloth out thoroughly and spread evenly
and smoothly over outer surface of cell.
h. Check all surfaces of cell. Leaks will be indicated by the appearance of red spots on the cloth.
If red spots appear on the cloth, they may be removed by soaking the cloth in the phenolphthalein
solution.
NOTE
The phenolphthatein solution and test cloth
are satisfactory only as long as they remain
clean. Indicator solution that is not in immediate use should be stored in a closed
container to prevent evaporation and deterioration.
13-25

NOTE

MODEL P172 OUTLINE.
(LARGER TANK)

Hinge for vent valve (12) must be
at top. Tube for valve extends
into fuel tank, then forward and
slightly upward.

SEE FIGURE 13-9A

3.
4.
REFER TO FIGURE 13-11 FOR PURGING TANKS 5.
Figure 13-12.

Adapter

8.
9.
10.

Filler Neck
Cap

13.
14.

Fuel Tank
Gasket

Washer

15.

Drain Plug

Fuel Tank - Model 172 and P172

i. After completion of test, remove all test plates
and test equipment. Allow cell to air out.
13-16. FUEL TANK REPLACEMENT - 150, 172,
AND P172.
NOTE
These airplanes are equipped with rigid, welded
aluminum fuel tanks located in the inboard wing
area. Since the installation is similar, the following general procedure may be followed for
all subject airplanes.
a. Remove fuel sump drain plug and drain fuel.
b. Remove fuel tank cover by removing attaching
screws.
c. Remove wing root fairings.
d. Disconnect all fuel and vent lines from fuel tank.
Remove fittings as necessary for clearance when removing tank.
13-26

Gasket
Transmitter

e. Disconnect electrical lead and ground strap from
fuel quantity transmitter. Remove transmitter by
removing attaching screws and carefully work it from
fuel tank.
f. Disconnect straps securing fuel tank and remove
the tank. Use care not to damage protruding fittings
and hose connections when removing the tank.
g. Install tank by reversing preceding steps.
NOTE
Throughout the airplane fuel system, from
the tanks to the engine-driven fuel pump or
carburetor, use Parker Sealube (or equivalent) as a thread lubricant or to seal a leaking
connection. Apply sparingly to male fittings
only, omitting the first two threads. Always
be sure that a compound, the residue from a
previously used compound, or any other
foreign material cannot enter the system.

13-17. REPLACEMENT OF FUEL GAGE TRANSMITTERS. (See figures 13-10, 13-11, and 13-12.)

structure and remove valve.
f. Reverse the preceding steps to install the valve.

a. Drain fuel from tank or cell
b. On Models 150, 172, and P172 series, remove
small access cover above fuel tank for access to fuel
gage transmitter. On the Models 180, 182, and 185,
remove wing root fairing.
c. Disconnect electrical lead and ground strap from
transmitter.
d. On Models 150, 172, and P172, remove screws
attaching transmitter to top of tank. On Models 180,
182, and 185, remove screws through unit and wing
root rib.
e. Replace transmitter by reversing preceding
steps. On rubberized fuel cells, no gasket paste
should be used.
f. Fill tank; check for leaks and correct gage reading.
NOTE

fittings.
Be sure grounding is secure and in accordance
with figure 13-9A.
13-18. CHECKING FUEL VENT. Field experience
has demonstrated that fuel vents can become plugged
with possible fuel starvation of the engine or collapse
of fuel cells. Also the bleed hole-in the vent valve
assembly could possibly become plugged, allowing
pressure from expanding fuel to pressurize the tanks.
The following procedure may be used to check the
vent and bleed hole in the valve assembly.
a. Attach a rubber tube to end of vent line under
the wing. On models with drain hole on lower side
of vent tube, tape hole closed.
b. On airplanes equipped with a vent for each tank,
plug vent on opposite wing from one being tested.
c. Blow into tube to pressurize tank. If air can be
blown into tank, vent line is open.
d. After tank is slightly pressurized, insert end of
tube into a container full of water and watch for continuous stream of bubbles which indicate bleed hole
in valve assembly is open and relieving pressure.
e. On airplanes equipped with a vent for each tank
repeat procedure for opposite tank.
NOTE
Remember that a plugged vent line or bleed
hole can cause either fuel starvation and collapsing of fuel cells or the pressurizing of the
tanks by fuel expansion.
13-19. FUEL SELECTOR VALVE REPLACEMENT.
(MODELS P172, 180, 185, AND PRIOR TO 172F.)
A fuel selector valve is installed in the Model 185
optional fuel system. To replace a fuel selector
valve proceed as follows:
a. Completely drain all fuel from wing tanks, fuel
strainer, fuel lines, and valve.
b. Remove tunnel cover rectangular access plate
and access plate on bottom of fuselage adjacent to
selector valve.
c. Disconnect and cap or plug all fuel lines at
selector valve.
d. Disconnect handle shaft from valve.
e. Remove screws or bolts attaching valve to

13-20. FUEL SELECTOR VALVE REPLACEMENT.
(MODEL 182 AND MODEL 172F AND ON.)
a. Completely drain all fuel from wing tanks, fuel
strainer, fuel lines, and valve.
b. Remove fuel selector valve handle and cup.
c. Remove console cover.
d. Unfasten and fold carpet back, then remove
access plates at bottom of console and just aft of
console.
e. Disconnect handle shaft from valve.
f. Disconnect and cap or plug all fuel lines at
selector valve.
g. Remove screws attaching valve to structure and
remove valve.
h. Reverse the preceding steps to install the valve.
Observe the note in paragraph 13-19.
13-21. FUEL SHUT-OFF VALVE REPLACEMENT.
(MODEL 150.)
a. Completely drain all fuel from wing tanks, fuel
strainer, fuel lines, and valve.
b. Remove shut-off valve handle.
c. Prior to the Model 150F, unfasten and fold carpet
back on the right side of the valve and remove access
plate just forward of the right seat. On the Model
150F and on, remove the right seat and the access
plate under it.
d. Disconnect and cap all lines at shut-off valve.
e. Remove bolts attaching valve and remove valve.
f. Reverse the preceding steps to install the valve.
Observe the note in paragraph 13-19.
13-22. FUEL SHUT-OFF VALVE REPLACEMENT.
(MODEL 185.)
a. Completely drain all fuel from wing tanks, fuel
strainer, fuel lines, and valve.
b. Remove access plate from underside of fuselage
below accumulator tank and shut-off valve.
c. Remove cotter pin attaching valve handle to
valve and remove handle.
d. Disconnect and cap or plug fuel line at shut-off
valve.
e. Screw valve from bottom of accumulator tank.
f. Reverse the preceding steps to install the valve.
Observe the note in paragraph 13-19.
13-27

MODEL 180, 182, AND 185

MODEL 172 & P172

NOTE

VIEW

1.
2.
3.
4.
5.

i
ng

Vent
Strut
Fairing
Tie-Down Ring

PERPENDICULAR TO
BOTTOM OF WING SKIN

Figure 13-13.
13-28

Fuel Vent Location

MODEL 180

NOTE
Model 185 and Model 150 standard fuel systems
utilize a fuel shut-off valve. Model 185 optional
fuel systems uses both a fuel shut-off valve and
a fuel selector valve.

1.
2.
3.
4.
5.
6.
7.

Nipple
O-Ring
Gasket
Cam
Washer
O-Ring
Cover

8. Screw
9. Spring
10. Housing
11. Roll Pin
12. Ball
13. Bushing
14. Body
15. Ball
Figure 13-14.

16.
17.
18.
19.
20.
21.
22.

Retainer
O-Ring
Ball
Spring
O-Ring
Nipple
Plug

Fuel Selector Valves (Sheet 1 of 2)
13-29

~~2~~

MODEL 185
SHUT-OFF VALVE

SQL----7

MODEL 182
(OPTIONAL ON MODEL 185)

1.
2.
3.
4.

5. Spring
6. Plug
7. Lockwasher
8. Screw

Body
Rotor
0-Ring
Seal

Figure 13-14.

Fuel Selector Valves (Sheet 2 of 2)

13-23. SELECTOR VALVE AND SHUT-OFF VALVE
REPAIR consists of replacement of seals, springs,
balls, and other detail parts. Figure 13-14 shows
the proper relationship of parts and may be used as
a guide during disassembly and assembly of these
valves. Do not disassemble Model 150 valve.
13-24. FUEL STRAINER REPLACEMENT AND
CLEANING. The fuel strainer is mounted on the
firewall in the engine compartment. On some models, the strainer is attached to a bracket mounted on
the firewall. The fuel strainer may be removed by
detaching fuel lines, disconnecting strainer drain
control, if used, and removing mounting bolts. Disassembly of the strainer shown on sheet 1 of figure
13-15 is accomplished by loosening the bolt at the
bottom of the strainer and swinging the arm aside.
Clean with solvent and dry with compressed air. Use
new ga-zkets at assembly. Be sure to resafety bottom
bolt. The fuel strainer shown on sheet 2 of figure
13-15 has an integral remote strainer drain control.
To disassemble this type strainer, proceed as follows:
a. Turn off fuel selector valve and drain strainer.

13-30

9. Washer
10. Cover
11. Ball
12. Roll Pin

b. Remove drain tube if installed, safety wire,
nut, and washer at bottom of filter bowl and remove
bowl.
c. Carefully unscrew standpipe and remove.
d. Remove filter screen and gasket. Wash filter
screen and bowl with solvent (Federal Specification
P-S-661, or equivalent) and dry with compressed
air.
e. Using a new gasket between filter screen and
top assembly, install screen and standpipe. Tighten
standpipe only finger tight.
f. Using all new O-rings, install bowl. Note that
step-washer at bottom of bowl is installed so that
step seats against O-ring. Connect drain tube if installed.
g. Turn on fuel selector valve, close strainer drain
and check for leaks. Check for proper operation of
strainer drain control.
h. Safety wire bottom nut to top assembly. Wire
must have right hand wrap, at least 45 degrees.
13-25. FUEL STRAINER DRAIN. All strainers are
equipped with drain valves, some of which are oper-

2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Clamp
Fuel Strainer Assembly
Washer
Nut
Elbow
Valve Body
Drain Tube
Valve Seat
Spring
Washer
0-Ring
Sleeve
Nut

16. Elbow
17. Nipple
18. Screw
19. Support Angle
20. Valve Shaft
21. Valve Plunger
22. Arm
23. Strainer Body
24. Gasket
25. Filter Screen
26. Glass Bowl
27. Bottom Cap
28. Arm Assembly

Figure 13-15.

12
21
THRU
17252533
F172-0139
P172D
18051496
185-0843

Fuel Strainer (Sheet 1 of 2)
13-31

SAFETY WIRE HOLE

15061153 & ON
17252534 & ON

F172-0140 & ON
18051497 & ON

18256040 & ON

185-0844 & ON

~
AFETY WIRE HOLE--

NOTE
Fuel strainers vary in methods of mounting and
strainer drain controls vary in routing for the
different models. On some models, a drain tube
is attached to standpipe (11) to drain fuel overboard.

1.
2.
3.
4.
5.

Spring
Washer
Plunger
Top Assembly
Drain Control

6.
7.
8.
9.

Plate
O-Ring
Gasket
Filter

Figure 13-15. Fuel Strainer (Sheet 2 of 2)
13-32

10.
11.
12.
13.
14.

Retainer
Standpipe
O-Ring
Bowl
O-Ring

4. Duct
SK 172-28 AVAILABLE FROM THE
CESSNA SERVICE PARTS CENTER
1.
2.
3.
4.
5.

Upper RH Engine Baffle
Union Assembly
Clamp
Duct
Firewall

Figure 13-15A.

9. Support Assembly

6.
7.
8.
9.
10.
11.

Drain Control
Bracket
Grommet
Support Assembly
Fuel Line
Nipple

15.

Elbow

12.
13.
14.
15.
16.

Fuel Strainer
Drain Line
Cover Assembly
Elbow
Primer Line

13
SERIALS 17252534 THRU 17256512

Fuel Strainer Blast Tube Installation - Model 172
13-32A

>II

1968 MO

1-^

1.
2.
3.
4.

Drain Tube
Fuel Strainer
Clamp Bolt
Bracket

Figure 13-15B.
13-32B

1968 MODEL 1721

5.
6.
7.
8.

Bracket
Control
Nut
Shield

i.
10.
11.
12.

Grommet
Elbow
Fuel Line
Firewall

Fuel Strainer Shroud Installation - Model 172

ated by a strainer drain control. The type shown on
sheet 2 of figure 13-15 is an integral drain which is
removed as the strainer is disassembled. Two types
of strainer drain controls are used with the strainer
shown on sheet 1 of figure 13-15. The type that uses
an arm to operate the valve may be disassembled and
reassembled while using the illustration as a guide.
The type that resembles a tee fitting should be disassembled and reassembled as follows:

Use care not to bend the control or damage
parts during disassembly or reassembly.
a. Remove clamp (2).
b. Unscrew nut (14) connecting the control to valve
body (7) and pull control out of the body.
c. To replace valve seat (9), remove the old seat
with a hook and tap the new seat into position.
d. To replace O-ring (12), remove the old one and
discard it. Place a smooth, thin-walled, wellgreased tube over spring and small washer (11) on
the end of the control (greased tape may be used)
and carefully slide the O-ring into position past the
washer. Remove the tube or tape.
e. From the cabin, pull the control knob out only
far enough to remove all slack between the parts at
the lower end of the control. Maintaining this position of the control, align the O-ring with washer (11)
and sleeve (13).
f. Insert the control into the valve body until it
bottoms. Pull the control knob out until the lower
end of the control can be pushed into the valve body

far enough for the O-ring to slip past the chamfer of
top of the valve body. After the O-ring is inside the
valve body, pull the control knob all the way out and
keep it out until nut (14) has been tightened. After
tightening the nut, release the control knob.
g. Reinstall clamp (2).
13-26. PRIMER SYSTEMS are all of the manually
operated type. Fuel is supplied by a line from the
fuel strainer to the plunger-type primer. Operating
the primer forces fuel to the engine. Several methods are used to distribute this fuel. On some models,
fuel is injected into intake manifolds or riser. Some
models use a tee fitting and prime two cylinders.
Other models use a primer distributor and prime
either five or six cylinders. Replacement of the
primer is accomplished by disconnecting the fuel
lines at the primer and removing the primer from
the instrument panel. Before installing a primer,
check it for correct pumping action and positive fuel
shut-off in the locked position. Primer lines should
be replaced when crushed or broken and should be
properly clamped to prevent fatigue due to vibration
and chafing.
13-27.

ELECTRIC AUXILIARY FUEL PUMP.

13-28. The electric auxiliary fuel pump used on the
Model 185 is a 35 gallon-per-hour pump supplying
a pressure of 23-24 psi when powered by 14 vdc.
The pump is mounted (see figure 13-16) on the firewall and is enclosed by a cooling shroud. An integral bypass and check valve permits fuel flow
through the pump even when the pump is not operat-

1. Fuel Strainer
2.
3.
4.
5.

Bolt
Nut
Washer
Bracket

6. Gasket
7.

Union

8. Nut
9. Clamp
10.
11.

Line
Elbow

12.

Pump

13.
14.

Grommet
Shroud

Figure 13-16.

Electric Auxiliary Fuel Pump Installation - Model 185
13-33

41/

1" .

"
3.

---- ni--

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Screw
Lockwasher
Cover
Grommet
Screw
Brush Retainer
Brush Assembly
End Bell
Bearing
Truarc Ring
Armature
Spring
Lockwasher
Field Assembly

15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.

Figure 13-17.
13-34

Shell
Nameplate
Spacer
Shaft End Bell
Screw
Retention Spring
Motor Shaft Pin
Spacer
Slinger Pin
Bearing O-Ring
Vane
Vane Pin
Bearing 0-Ring

28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.

Body Bearing
Screw
Pump Body
Swing Check Assembly
Spring
Adjusting Plug
Nameplate
O-Ring
Housing Pin
Bearing Plate
Spacer
Rotor and Shaft Assembly
Bearing and Seal Assembly
Slinger Ring

Electric Auxiliary Fuel Pump-Model 185

drain line from the pump prevents entry of fuel into

(27), and body bearing (28) from pump body (30).

the electric motor, in the event of an internal leak.
13-29. DISASSEMBLY. (See figure 13-17.)
a. Remove screws (29) and washers (13), and separate motor and- pump.

CAUTION
Use care when removing screws (29) as
spring (20) is under compression.
13-30. DISASSEMBLY OF MOTOR. (See figure
13-17.)
a. Loosen screws (19) but do not remove.
b. Remove cover (3) by removing screws (1) and
washers (2).
c. Remove brush holders (6) and brush assemblies
(7) by removing screw (5).
d. Loosen screws (19) and remove end bell (8), but
do not remove screws (19) from shaft end bell (18).
e. Remove bearing (9) from end bell (8).
f. Remove armature (11).
g. Remove springs (12), washers (13), field (14),
shell (15), spacers (17), screws (19), and washers
(2) from shaft end bell (18).
h. Remove bearing (9) from shaft end bell (18).
i. Do not remove spacer (22), Truarc ring (10), or
motor shaft pin (21) unless replacement is necessary.
13-31. INSPECTION OF MOTOR COMPONENTS.
a. Thoroughly wash all parts of motor, except
brushes (7), bearings (9), armature (11), and field
(14) in cleaning solvent (Federal Specification P-S661, or equivalent) and dry parts with filtered compressed air.
b. Wipe parts not washed in solvent with acleancloth.
c. Inspect all parts for damage and evidence of
excessive wear.
d. Inspect all parts for breakage or distortion.
e. Replace any worn or damaged parts.

13-32. REASSEMBLY OF MOTOR.

The assembly

procedure for the motor is the reverse of the disassembly procedure. When reassembling, pay
special attention to the following items:
a. Spacers (17), springs (12), and washers (13)
must be held in place by screws (19) when assembling
end bell (8).
b. Compress end bell (8) until screws (19) are engaged, then tighten screws (19) evenly to a torque
value of 10 pound-inches.
c. Brushes (7) are contoured, therefore the contour of the brush must match the armature commutator when being installed.
13-33. DISASSEMBLY OF PUMP.
a. Remove pin (23) and remove slinger ring (41).
b. Remove bearing and seal assembly (40) and rotor
and shaft assembly (39) from pump body (30).
NOTE
Vanes (25) and pins (26) are attached to rotor
(39) and ar: removed with rotor and shaft assembly.

13-34. INSPECTION OF PUMP COMPONENTS.
a. Thoroughly wash all parts in cleaning solvent
(Federal Specification P-S-661, or equivalent) and
dry with filtered compressed air.
b. Inspect all parts for damage and evidence of
excessive wear.
c. Replace all 0-rings, and bearing and seal
assembly.
d. Replace any damaged or worn parts.
13-35. REASSEMBLY OF PUMP. The assembly
procedure for the pump is the reverse of the disassembly procedure. When reassembling, pay
special attention to the following items:
a. Pin (36) must be correctly located in pump
body (30) in order to properly position bearing plate
(37) and spacer (38). Location holes in bearing plate
and spacer must align with pin.
b. Vanes (25) and pins (26) must be assembled to
the rotor and shaft assembly (39), and held in place
while installing in pump body (30).
c. Use a suitable lubricant on O-rings to prevent
damage when installing. Recommended lubricant for
O-rings is Dow Corning Silicone No. 4.
13-36. DISASSEMBLY OF BYPASS AND PRESSURE
RELIEF.
a. Remove nameplate (34), plug assembly (33),
spring (32), and swing check assembly (31) from
pump body (30).
13-37. INSPECTION OF BYPASS AND PRESSURE
RELIEF.
a. Thoroughly wash all parts in cleaning solvent
(Federal Specification P-S-661, or equivalent) and
dry with filtered compressed air.
b. Inspect all parts for damage and evidence of
excessive wear.
c. Inspect swing check assembly seat for damage.
d. Replace O-rings and all other damaged parts.
13-38. REASSEMBLY OF BYPASS AND PRESSURE
RELIEF. The assembly procedure for the bypass
and pressure relief is the reverse of the disassembly
procedure. When reassembling, pay special attention
to the following:
a. Install swing check assembly (31) so it is seated
on seat in pump body (30). The valve must open inwardly.
13-39. ADJUSTING PRESSURE RELIEF.
a. Install pump assembly in appropriate test stand
(see figure 13-18).
b. While maintaining a no flow condition, adjust
plug (33) until a relief pressure of 23 to 24 psi is
obtained.
c. After correct pressure is obtained, seal plug
(33) at threads with Epocast Epoxy No. 212-10 mixed
with hardener No. 9816. (Reference: Furane Plastics. )
d. Allow Epoxy to dry and install nameplate (34).
13-40. FUNCTIONAL TEST PROCEDURE. Each
unit shall be set up in test stand as shown in figure
13-35

Hg MANOMETER

BYPASS
PUMP

GAGE

Figure 13-18. Test Stand Schematic
13-18 and functional tested as follows:
a. Flow Tests.
1. Apply 14 vdc to test unit.
2. With valves A and B closed, adjust valve C
to outlet pressures of 5.0 psi increments until maximum relief is reached at no flow.
NOTE
No flow pressure shall be 27. 5 psig maximum.
b. Bypass Pressure Drop.
1. With unit shut-off, open valves A and B.
2. Close valve C and energize bypass pump.
3. Adjust valve B until flowmeter reads 40 gph
and record inches of mercury as read on Hg manometer.
NOTE
Pressure drop shall not exceed 0. 60 inches of
mercury. Bypass pressure drop is 0. 35 psi
maximum at 40 gph.
c.

Installation Resistance Test.
1. Apply 50 volts dc across both leads and pump
case. Insulation resistance shall be 50 megohms
maximum.
13-36

13-41. ELECTRIC FUEL PUMP CIRCUIT - Model
185. (See figures 13-3 and 13-4.) The electric
auxiliary fuel pump, which supplies fuel flow for
starting and for engine operation if the engine-driven
fuel pump should fail, is controlled by the auxiliary
fuel pump switch mounted on the instrument panel.
The switch is a three-position toggle switch. The
down position, labeled LOW (PRIME) or START, is
used for starting the engine. With the switch in this
position and the ignition-starter switch turned to
START, the auxiliary fuel pump will operate at a
low flow rate (providing the proper fuel mixture for
starting) as the engine is being turned with the
starter.
NOTE
The auxiliary fuel pump will not operate with
the switch in the LOW (PRIME) or START position until the ignition-starter switch is turned
to the START position.
The up position of the switch, labeled HIGH or
EMERGENCY, is used for engine operation if the
engine-driven fuel pump should fail, or for vapor
purging in extremely hot weather. When the switch
is in this position, the auxiliary fuel pump can operate at two flow rates depending on the setting of the
throttle. With the throttle at a cruise setting, the

auxiliary pump is operating at maximum capacity,
supplying sufficient fuel flow to maintain flight with
the engine-driven pump inoperative. When throttle
is moved toward the closed position, as during letdown, landing, and taxiing, a mechanically-actuated
switch electrically reduces the auxiliary fuel pump
flow rate by means of a resistor in the pump power
circuit. This action automatically prevents an excessively rich mixture during these periods of reduced engine speed.
The auxiliary fuel pump is not to be on HIGH during
normal operation because, with the engine-driven
pump functioning, a fuel/air ratio considerably
richer than best power is produced. If fuel vapor
is affecting engine operation, the vapor may be
purged by turning the auxiliary fuel pump switch to
HIGH or EMERGENCY and leaning the mixture as
required to prevent an excessively rich mixture.
Successful vapor purging is evidenced by smooth
engine operation and steady and normal fuel flow
indications with the auxiliary fuel pump switch OFF.
NOTE
If the auxiliary fuel pump switch is accidentally
turned to HIGH or EMERGENCY (with master
switch on) with the engine stopped, intake
manifolds will be flooded unless the mixture
is in idle cut-off.

The center position of the auxiliary fuel pump switch
is OFF.
13-42. RIGGING THROTTLE-OPERATED SWITCH.
The Model 185 is equipped with a throttle microswitch
which slows down the electric fuel pump whenever the
throttle is retarded while the electric pump is being
used. The microswitch should slow down the pump
as the throttle is retarded to approximately 16 inches
of mercury manifold pressure.
a. Start engine and set throttle to obtain 16 inches
of mercury manifold pressure. Carefully mark
throttle position, then stop engine.
NOTE
The throttle may be maintained in this position
if desired, for the engine may be stopped by
use of the mixture control and ignition switch.
b. Loosen screws on the throttle microswitch (located on induction airbox) and adjust microswitch as
required to cause the electric fuel pump to slow down
as the throttle is retarded to the marked position.
With master switch ON, auxiliary fuel pump in HIGH
or EMERGENCY, and mixture control in IDLE CUTOFF, listen for change in sound of electric fuel pump
as it slows down (16±1 inches of mercury).

SHOP NOTES:

13-37

SECTION 14
PROPELLERS

TABLE OF CONTENTS

Page

PROPELLERS ...............
Repair .................
FIXED-PITCH PROPELLERS ....
Removal
................
Installation ...............
Repair ..
..........
..........
CONSTANT-SPEED PROPELLERS .....
Trouble Shooting .
..........
Removal of McCauley Propeller .....

14-1
14-1
14-2
14-2
14-2
14-2
14-5
14-5
14-7

Installation of McCauley Propeller
....
14-7
Cleaning of McCauley Propeller Hub . . . 14-7
Removal of Hartzell Propeller ......
14-7
Installation of Hartzell Propeller .....
14-7
PROPELLER GOVERNORS .........
14-11
Trouble Shooting ............
. 14-11
Removal ..............
....
14-11
Installation ...............
14-11
High Rpm Stop Adjustment ........
14-11
. 14-11
Rigging Propeller Control ......

NOTE
Federal Aviation Regulations, Part 43, (FAR 43) define major and minor
repairs and alterations and who may accomplish them. This section may
be used as a guide, but the Federal Aviation Regulations and the propeller
manufacturer's instructions must be observed.

14-1.

PROPELLERS.

14-2. All-metal, fixed-pitch propellers are used on
Models 150 and 172. All other aircraft described
in this manual are equipped with all-metal, constantspeed, governor-regulated propellers. All propellers are equipped with spinners,
14-3. REPAIR of metal propellers first involves
evaluating the damage and determining whether the
repair will be a major or minor one and, in accordance with Federal Aviation Regulations, who is permitted to accomplish the repair.
a. General Repair Considerations:
Under no circumstances are the raised edges
of defects to be corrected by peening. No welding, soldering or compounds of any nature are
to be used to fill or correct defects. All repair
is to be in accordance with standard approved
and accepted practice.
More than one defect on blade is not cause for
considering blade not airworthy if repair is within indicated limits. A reasonable number of repairs per blade is permissible if their location
with respect to each other is not such as to form
a continuous line that may materially weaken
blade. Any transverse crack shall be cause
for considering blade not airworthy.

Repair necessitating the removal of an appreciable amount of metal shall be reason to check
horizontal and vertical balance.
The repair of defects is permissible providing
the treatment does not materially weaken the
blade, reduce its weight, or impair its performance.
b. Defects on Thrust Face or Camber Side:
Repair by removal of metal to form shallow,
large radius, round bottomed depressions.
Periodic inspection during repair should be
made to avoid removal of excessive amounts
of metal. All raised edges should be carefully
smoothed out to reduce the area of the defect
and the amount of metal to be removed. Repair
with suitable fine cut files and coarse grain
emery cloth and smooth all edges and surfaces
with fine grain emery cloth. Any blade repair
on these surfaces which necessitates a depression that exceeds the' manufacturer's tolerances
or those listed in FAR 43 shall be cause for
considering blade not airworthy.
c. Defects on Leading and Trailing Edge:
Repair defects as outlined in step "b" with suitable half round file and emery cloth. Carefully
smooth all edges of repaired defect. Any blade
14-1

repair on leading and trailing edges which necessitates metal removal that exceeds the manufacturer's tolerances or those listed in FAR 43
shall be cause for considering blade not airworthy.
Blades that have leading or trailing edges pitted
from normal wear may be reworked by removing
sufficient metal to eliminate the pitting. Start
well back from the edge and work over the edge
in such a manner that the contour of the blade
remains substantially the same. Avoid abrupt
section changes and blunt edges. Permissible
reductions in blade thickness and width, listed
in the manufacturer's publications or FAR 43,
must be observed,
d.Tip-Damage:
Damage on blade tips may be removed in accordance with steps "b" and "c, " as long as
metal removed is within the tolerances specified. Damage which cannot be repaired by
local removing of metal may be repaired by
removing metal so as to shorten blades, although shortening blades is a propeller major
repair. Any shortening of one blade requires
an identical shortening of the other one, and
any change in tip plan form or contour of one
blade requires an identical change on the other
one. Limitations concerning shortening of
blades are specified in the manufacturer's
publications or FAR 43.
e. Refinishing:
Prior to corrosion protection treatments, all
repair areas should be smoothly polished out and
blended in to finish repair and improve appearance. Wherever possible, all repaired blades
should be anodized in a sulfuric acid anodize
bath. The blades must be anodized with loose
blade retention hardware on shank end; therefore, the blade must be supported vertically
with steel hardware out of the solution and
suitably protected to be unaffected by fumes.
The same holds true for caustic baths.

SHOP NOTES:

14-2

Where anodizing is not readily available, local
repaired or inspected areas may be treated by
other approved methods for corrosion protection;
so-called chromodizing, alodine solution, painting, etc. It is doubtful that the finish of these
treatments, other than sulfuric acid anodize,
will blend in with regards to appearance. If
desired, both camber and thrust face sides may
be painted with zinc chromate primer and black
lacquer to improve appearance. The thrust face
side should always be painted.
14-4.

FIXED-PITCH PROPELLERS.

14-5. REMOVAL.
a. On the Model 150, remove the small spinner.
If the optional large spinner is installed, remove the
spinner dome.
b. On the ModelI72, remove the-spinner-dome;c. Remove propeller mounting bolts and pull the
propeller forward to remove.
d. The Model 150 small spinner mounting bracket
is attached by two of the propeller mounting bolts.
The Model 150 large spinner and the Model 172 spinner are attached to two spinner bulkheads, one in
front of the propeller and one aft of the propeller.
These bulkheads are secured by propeller mounting
bolts and will be freed by removal of the bolts as the
propeller is removed.
14-6. INSTALLATION.
a. Clean mating surfaces of propeller and the
crankshaft flange.
b. On the Model 150, the propeller must be installed to "trail" 30 ° after top center of the crankshaft.
c. Position propeller and spinner bulkhead or
spinner bracket as shown in figure 14-1 and install
propeller mounting bolts. Tighten evenly, torque
to the values shown, and safety as required. The
spinner bulkheads must be positioned so propeller
blades will emerge from spinner domes with ample
clearance.
d. Install spinner or spinner dome.
14-7. REPAIR of fixed-pitch propellers is included
in paragraph 14-3.

NOTE
Install Model 150 propeller to

MODEL 150
STANDARD SPINNER

NOTE
Spinner bulkhead (6) was not used
the early 1963 models. However,
Cessna Service Kits have made this
installation available for the earlier
Model 150 and 172 Series airplanes.

NUTS TO 55-65 LB-FT.

1. Screw
2. Spinner Dome
3. Bracket

4. Washer
5. Bolt
6. Spinner Bulkhead (Front)

Figure 14-1.

7.
8.
9.

Spinner Bulkhead (Rear)
Dowel Pin
Nut

Fixed Pitch Propeller Installation
14-3

VERTICAL A CRANKCASE
30 ° I5O

2 DOWEL HOLES

ENGINE-PROP-FLANG E-ASVIEWED FROM THE FRONT
NOTE
If the reduction gear housing has been removed from the engine,
install it as follows: Position prop shaft with dowel holes in the
location shown, when No. 1 cylinder is on top dead center and
on compression stroke. Change gear mating as required to position prop shaft as shown. Secure the reduction gear housing to
the engine.
Figure 14-2. Reduction Gear Mating - Model P172

TORQUE PROPELLER MOUNTING
NUTS TO 55-65 LB-FT.

/(~

14-4

Spinner Dome
Cylinder
Propeller
Spinner Bulkhead

5.
6.

Washer
Nut

7. Dowel Pin
8. Screw
9. Washer

Figure 14-3.

1.
2.
3.
4.

McCauley Propeller - Model P172

14-8.

CONSTANT-SPEED PROPELLERS.

14-9. McCauley propellers are used on all models
that require constant-speed propellers except some
1963 Model 182F aircraft which are equipped with an
alternate Hartzell propeller. Both McCauley and
14-10.

Hartzell propellers are single-acting propellers in
which oil pressure, boosted and regulated by a governor, is used to increase blade pitch, and the
natural, centrifugal twisting moment of the rotating
blades, and the force of an internal spring, are used
to decrease blade pitch.

TROUBLE SHOOTING.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

FAILURE TO CHANGE PITCH.
Control disconnected or
broken.

Check visually.

Connect or replace control.

Governor not correct for
propeller. "Sensing"
wrong.

Check that correct governor
is installed.

Install correct governor.

Defective governor.

See paragraph 14-18.

Defective pitch changing
mechanism or excessive
blade friction.

Lubricate Hartzell propeller.
propeller manually.

Check

Propeller repair or replacement is required.

FAILURE TO CHANGE PITCH FULLY.
Improper rigging of
governor control.

Check that arm on governor has
full travel

Rig correctly.

Defective governor.

See paragraph 14-18.

SLUGGISH RESPONSE TO PROPELLER CONTROL.
Excessive friction in pitch
changing mechanism or
excessive blade friction.

Lubricate Hartzell propeller.
propeller manually.

Check

Propeller repair or replacement is required.

STATIC RPM TOO HIGH.
Governor high rpm stop set
too high.

See "Note" at end of this chart.

Rig correctly.

Defective governor.

See paragraph 14-18.

Incorrect propeller or incorrect low pitch blade angle.

Check aircraft specifications.

Install correct propeller,
with correct blade angle.

Governor high rpm stop set too
low.

See "Note" at end of this chart.

Rig correctly.

Defective governor.

See paragraph 14-18.

Incorrect propeller or incorrect
low pitch blade angle.

Check aircraft specifications.

Install correct propeller,
with correct blade angle.

STATIC RPM TOO LOW.

14-5

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

ENGINE SPEED WILL NOT STABILIZE.

Sludge in governor.

See paragraph 14-18.

Air trapped in propeller
actuating cylinder.

This condition may occur after
the propeller has been reinstalled
or has been idle for an extended
period,

Trapped air should be purged
by exercising the propeller
several times prior to take-off
after the propeller has been
reinstalled or has been idle for
an extended period.

Excessive friction in pitch
changing mechanism or
excesslve-blade-friction.-

Lubricate Hartzell propeller.
propeller manually.

Propeller repair or replacement is required.

Defective governor.

See paragraph 14-18.

Check

See paragraph 14-18.

OIL LEAKAGE AT MOUNTING FLANGE.
Damaged O-ring seal
between engine and
propeller.

Check visually for oil leakage.

Replace O-ring seal.

Foreign material between
engine and propeller mating
surfaces or nuts not tight.

Check visually for oil leakage.

Clean propeller and engine
mating surfaces and tighten
nuts properly.

OIL LEAKAGE BETWEEN HUB AND CYLINDER. (McCAULEY)
Defective gasket or screws
not tight.

Check visually for oil leakage.

Replace gasket and tighten
screws properly.

GREASE LEAKAGE AT GREASE FITTING. (HARTZELL)
Loose or defective grease
fitting.

Check visually for grease
leakage.

Tighten loose grease fitting;
replace, if defective.

OIL OR GREASE LEAKAGE AT ANY OTHER PLACE.
Defective seals, gaskets,
threads, etc. or incorrect
assembly.

Check visually for oil or grease
leakage.

Propeller repair or replacement is required.

NOTE
It is possible for either the propeller low pitch (high rpm) stop or the governor
high rpm stop to be the high rpm limiting factor. It is desirable for the governor
stop to limit-the high rpm at the maximum rated rpm for a particular airplane.
Due to climatic conditions, field elevation, low pitch blade angle, and other considerations, an engine may not reach rated rpm on the ground. It may be necessary to readjust the governor stop after test flying to obtain maximum rated rpm
when airborne.

SHOP NOTES:

14-6

14-11. REMOVAL OF McCAULEY PROPELLER
a. Remove spinner dome.
b. If used, remove spinner support and spacers
from front of propeller.
c. Remove propeller mounting nuts and pull propeller forward to remove.
NOTE
As the propeller is separated from the engine,
oil will drain from the propeller and crankshaft cavities.
d. The spinner bulkhead on some models is located
between the propeller and the crankshaft flange and
is freed by propeller removal. On other models, the
spinner bulkhead is attached by six lugs which must
be removed before the bulkhead can be removed from
the crankshaft flange.
14-12. INSTALLATION OF McCAULEY PROPELLER
a. On models using the spinner bulkhead with attaching lugs, slide the bulkhead over the crankshaft flange
and install attaching lugs. On models where the bulkhead is located between the propeller and the crankshaft flange, position the bulkhead on the propeller
before mounting the propeller.
NOTE
When installing spinner bulkheads, position
them so the propeller blades will emerge from
the spinners with ample clearance. Avoid
scraping metal from the spinner bulkhead and
wedging scrapings between the propeller and
the engine flange. Trim the inside diameter
of the bulkhead as necessary when installing
a new one. See figure 14-2 for mating of
crankshaft and propeller gears if housing was
removed from geared engines,
b. Remove any nicks, burrs, or sharp edges from
the crankshaft, and clean the propeller and cranksh- t cavities and mating surfaces.
c. Lightly lubricate a new O-ring and the crankshaft pilot, and install the O-ring in the groove in
the propeller hub.
d. Check that the two dowel pins are in place in the
aft side of the propeller hub. Align mounting holes
and slide propeller carefully over the crankshaft
pilot.
e. Install mounting nuts, tighten evenly, and torque
to 55-65 lb-ft.
NOTE
Washers are used under the mounting nuts on
some models and are not used on others. Install them if originally used.
f. Position spacers and spinner support, if used,
on front of propeller.
g. Reinstall spinner dome.

14-13.
HUB.

CLEANING OF McCAULEY PROPELLER
NOTE

Disassembly beyond the following procedure
is not recommended except by properly authorized propeller shops.
a. Remove spinner dome, and spinner support and
spacers, if used.
b. Remove cylinder from front of propeller hub.
c. Use a solution of one part light engine oil and
two parts solvent to clean exposed parts and the interior of the cylinder. Dry gently with compressed
air, then use clean engine oil to lubricate parts
lightly before assembly.
d. Install new O-rings and gaskets at each cleaning of propeller hub.
e. Reinstall cylinder.
f. Position spacers and spinner support, if used,
on front of propeller.
g. Reinstall spinner dome.
14-14. REMOVAL OF HARTZELL PROPELLER
a. Remove spinner dome.
b. Remove spacers and spinner support from front
of propeller. If desired, spinner support bulkhead
may be removed from the front of the propeller.
c. Remove propeller mounting nuts and washers,
and pull propeller forward to remove.
NOTE
As the propeller is separated from the engine,
oil will drain from the propeller and crankshaft cavities.
d. If desired, the spinner bulkhead may be removed
from the propeller hub.
14-15. INSTALLATIONOF HARTZELLPROPELLER.
a. If the spinner bulkhead was removed, reassemble
it to the propeller hub, with the spacers located between the bulkhead and the hub. Torque to 20-22 lbft (do not over-torque).
b. Remove any nicks, burrs, or sharp edges from
the crankshaft, and clean the propeller and crankshaft cavities and mating surfaces.
c. Lightly lubricate a new O-ring and the crankshaft pilot and install the O-ring in the groove in the
propeller hub.
d. Check that the two dowel pins are in place in
the aft side of the propeller hub. Align mounting
holes and slide propeller carefully over the crankshaft pilot.
e. Install mounting nuts and washers, tighten evenly,
and torque to 60-65 lb-ft.
f. Reinstall the spinner support bulkhead if it was
removed from the front of the propeller.
g. Position spacers and spinner support on spinner
support bulkhead.
h. Reinstall spinner dome.

14-7

TORQUE PROPELLER MOUNTING
NUTS TO 55-65 LB-FT.

PRIOR TO 1967 MODEL
180 AND SKYWAGON

NOTE
15

Use spacers (4) as required to
cause a snug fit between spinner
dome and spinner support.
10

THRU

MODEL 182G

MODEL 182H

AND ON

1.
2.
3.
4.
5.

Spinner Dome
Screw
Spinner Support
Spacer
Cylinder

6.
7.
8.
9.
10.

Figure 14-4.
14-8

Screw
Stud
Fillet
Nut
Lug

McCauley Propeller (Sheet 1 of 2)

11.
12.
13.
14.
15.

Nut
Spinner Bulkhead
O-Ring
Dowel Pin
Propeller

NOTE
Because of dowel pin location, lugs (13)
are reversed on Model 180 installations.

14 15

5
4
3

TORQUE PROPELLER MOUNTING
NUTS TO 55-65 LB-FT.

1967 MODEL 180 AND
1967 SKYWAGON & ON

1.
2.
3.
4.
5.

6.
7.
8.
9.
10.

Spinner Dome
Spinner Support
Spacer
Cylinder
Screw

Figure 14-4.

Propeller
Stud
Dowel Pin
O-Ring
Fillet

11. Engine Crankshaft
12. Spinner Bulkhead
13. Lug
14. Washer
15. Nut

McCauley Propeller (Sheet 2 of 2)

SHOP NOTES:

14-9

31
14
NOTE
Use spacers (22) as required to cause a snug
fit between spinner dome and spinner support.

(l\-5

|F^^^~~

\s
\

\^^~

~~/

5I~

TORQUE PROPELLER MOUNTING
NUTS 60 TO 65 LB-FT. TORQUE
SPINNER BULKHEAD MOUNTING
NUTS 20 TO 22 LB-FT (DO NOT
OVER-TORQUE).

21
24

1.
2.
3.
4.
5.
6.

7. Lubricate 630 AA (Fiske Brothers. Toledo,
24 -Ohio).
This grease will bleed oil in hot weather.
It is recommended only for lubrication of the
blade pilot tubes, but not the blade bearings.
LIST OF APPROVED GREASES
8. RPM Aviation Grease No. 1 (Standard Oil Co. of
California).
MIL-G-23827.
9. Lubriplate 707 (Fiske Brothers, Toledo, Ohio).
Stroma HT-1 (Z-801 Grease). Union Oil Co. of
10. Mobilgrease Aero Lo-Hi PD-535-K (Socony
California.
Vacuum Oil Co.).
Gulflex Moly for blade bushings.
11. No. 84 Medium Grease (Keystone Lubricating
Gulflex A. This grease is recommended for the
Co. ).
blade ball bearings as it will not bleed oil in hot
12. Texaco Regal Starfax Special.
weather.
13. Molub-Alloy No. 2 Grease -10"F.
RPM Aviation Grease No. 2 (Standard Oil Co. of
No. 1 Grease -25" F. (Imperial Oil & Grease
California).
Co., Los Angeles, California).
Stroma LT-1 (Z-815 Grease). Union Oil Co. of
14. Germany - Calypsol H729 (German Calypsol
California.
Company, Dusseldorf).
1.
2.
3.
4.
5.
6.
7.
8.

Spinner
Fillet
Rivet
Screw
Washer
Lockwasher
Bolt
Washer

9. Propeller
10. Spacer
11. Spinner Bulkhead
12. Nut
13. Engine Crankshaft
14. Washer
15. Nut
16. O-Ring

Figure 14-5. Hartzell Propeller
14-10

17. Dowel Pin
18. Grease Fitting
19. Locknut
20. Low Pitch Stop
21. Spinner Support Bulkhead
22. Spacer
23. Spinner Support
24. Screw

14-16.

PROPELLER GOVERNORS.

14-17. The propeller governor is a single-acting,
centrifugal type, which boosts oil pressure from the
engine and directs it to the propeller where the oil
is used to increase blade pitch. A single-acting governor uses oil pressure to effect a pitch change in
one direction only; a pitch change in the opposite
direction results from propeller counterweights,
centrifugal twisting moment of rotating blades, compressed springs, or a combination of some of these
forces. Oil pressure is boosted in the governor by a
gear type oil pump. A pilot valve, flyweights, and a
speeder spring act together to open and close governor oil passages as required to maintain a constant
engine speed.
NOTE
Outward physical appearance of specific governors is the same, but internal parts determine
whether it uses oil pressure to increase or decrease blade pitch. Always be sure the correct
governor is used.
14-18. TROUBLE SHOOTING. When trouble shooting
the propeller-governor combination, it is recommended
that a governor known to be in good condition be installed
to check whether the propeller or the governor is at
fault. Removal and replacement, high-speed stop adjustment, desludging, and replacement of the governor
mounting gasket are not major repairs and may be
accomplished in the field. Repairs to propeller governors are classed as propeller major repairs in
Federal Aviation Regulations, which also define who
may accomplish such repairs.
14-19. REMOVAL.
a. Remove cowling and engine baffles as required
for access.
b. Disconnect governor control from governor.
c. Remove nuts and washers securing governor to
engine, and pull governor from mounting studs.
d. Remove gasket between governor and engine
mounting pad.
14-20. INSTALLATION.
a. Wipe governor and engine mounting pad clean.
b. Install a new gasket with the raised surface of
the screen away from the engine pad.
c. Position governor on mounting studs, aligning
STOP
governor splines with splines in engine, and install
mounting nuts and washers. Do not force spline engagement. Rotate engine crankshaft slightly and
splines will engage smoothly when properly aligned.
d. Connect governor control to governor and rig.
e. Reinstall parts removed for access.
14-21. HIGH RPM STOP ADJUSTMENT.
a. Remove safety wire (not used on some governors)
from the high-speed stop screw and loosen the jam nut.
b. Turn the stop screw in to decrease maximum rpm
and out to increase maximum rpm. One full turn of

operate propeller and governor. Refer to the "Note"
at the end of the propeller trouble shooting chart.
14-22. RIGGING PROPELLER CONTROL.
a. Disconnect control end from governor arm.
b. Place propeller control in the cabin full forward,
then pull it back 1/8" to 1/4" and lock in this position.
This will allow "cushion" to assure full contact with
the governor high rpm stop screw.
c. Place governor arm against high rpm stop screw.
d. Loosen jam nut and adjust control rod end until
attaching holes align while governor arm is against
high rpm stop screw. Be sure to maintain sufficient
thread engagement of the control and rod end. If necessary, shift the control in its clamps to achieve this.
e. Attach control rod end to the governor arm,
tighten the jam nut, and install all safeties.
f. Operate the control to see that the governor arm
attains full travel in both directions.
NOTE
Some models are equipped with an offset extension
to the governor arm. The offset extension has an
elongated slot to permit further adjustment. The
preceding steps may still be used as an outline of
the rigging procedure. The result of rigging,
in all cases, is full travel of the governor arm,
with some "cushion" at the full-in position.
MODEL P172

GOVERNOR ARM
HIGH-SPEED STOP SCREW

JAM NUT

OTHER MODELS
HIGH-SPEED

JAM

GOVERN

the stop screw is approximately 25 rpm.
c. Make propeller control linkage adjustments as
necessary for full travel.
d. Tighten jam nut, safety stop screw, and test

Figure 14-6.

Governor High-Speed Stops
14-11

SECTION 14A
PROPELLER

NOTE
Federal Aviation Regulations, Part 43 (FAR
43) define major and minor repairs and alterations and who may accomplish them.

14A-1.

PROPELLER.

14A-2. An all-metal, fixed-pitch propeller is used
on the 1968 Model 1721. The propeller is equipped
with a spinner. A spacer is installed between the
engine crankshaft and spinner aft bulkhead.
14A-3. REPAIR. Repair of propellers shall be
accomplished as stated in Federal Aviation Regulations, Part 43 (FAR43) and the propeller manufacturer's Service Manual. The propeller manufacturer's Service Manual is available from the Cessna
Service Parts Center.
14A-4. REMOVAL. (See figure 14A-1.)
a. Remove spinner dome.
b. Remove six propeller mounting bolts and pull
forward to remove.
c. The propeller spinner bulkheads and spacer are
secured by the propeller mounting bolts. Use care
to avoid damage to these parts when removing the
propeller.
NOTE
After removal of the propeller, the starter
ring gear support assembly may be removed
from the engine crankshaft. Loosen alternator adjusting arm and disengage alternator
drive pulley belt from pulley on aft face of
starter ring gear support assembly.

14A-5. INSTALLATION.
a. If the starter ring gear support assembly was
removed, clean mating surface of support assembly
and engine crankshaft.
b. Place alternator drive belt in the pulley groove
of the starter ring gear support. Fit starter ring
gear assembly over propeller flange bushing of the
crankshaft.
NOTE
Make sure the bushing hole in the ring gear
support that bears the identification "O", is
assembled at the "0" identified crankshaft
flange bushing. This bushing is marked "O"
by an etching on the crankshaft flange next
to the bushing. The starter ring gear must
be heated correctly to assure proper alignment of the timing marks on the ring gear.
c. Clean mating surfaces of propeller, spinner
bulkheads, propeller spacer, and ring gear support
and assemble propeller, bulkheads and spacer.
d. Locate top center (TC) mark on aft face of starter ring gear support and with propeller blade over
TC mark, rotate propeller clockwise (as viewed from
front of engine) to first bushing, install propeller.
e. Tighten propeller mounting bolts evenly and
torque to the value shown in figure 14A-1.
f. Install spinner.
g. Adjust alternator drive belt tension as outlined
in Section 17.

14A-1

NOTE
TORQUE PROPELLER MOUNTING BOLTS
TO 45 LB-FT.

And,
6

Figure 14-1.
14A-2

1.
2.
3.
4.
5.
6.
1
7.
8.

Spinner Dome
Forward Spinner Bulkhead
Propeller
Engine Crankcase
Ring Gear Support Assembly
Spacer
Rear Spinner Bulkhead
Dowel Pin

Propeller Installation

SECTION 15

UTILITY SYSTEMS

TABLE OF CONTENTS
HEATING ............
TROUBLE SHOOTING ...........
REPLACEMENT AND REPAIR .......
CABIN AIR VENTS .............
OXYGEN SYSTEM ............
Maintenance Precautions ........
Replacement of Components
(Prior to 1965) ............

Page
15-1
15-1
15-1
15-1
. 15-9
15-9

15-9
15-13
.15-13
15-14
15-14

15-9

15-1. HEATING.
15-2. Cabin heat, defrosting and ventilation are provided by manifold heaters, ducting and valves which
allow the entry of heated or unheated air to the cabin
outlets. The only moving parts of the system are the
valves and their controls, hence there is little mechanical wear involved. Normally the only maintenance
check required on the heating system is careful examination to make sure that the heater muff has no burned
spots or cracks which could allow exhaust fumes to
enter the system and a check of hoses and ducting to
make sure that air passage is unobstructed. Heater
valves should be checked periodically to insure proper operation.
15-3.

Replacement of Components
(1965 & on). .............
Inspection Requirements ........
Functional Test ...........
Charging ..............
Cleaning Oxygen Masks .........

firewall with Pro-Seal #700 (Coast Pro-Seal Co.,
Chemical Division, 2235 Beverly Blvd., Los Angeles,
Calif.), or equivalent compound.
15-5.

REPLACEMENT AND REPAIR.

15-6. Figures 15-1 thru 15-6 show heating, defrosting and ventilating systems, and may be used
as guides during replacement of components. Burned,
frayed, or crushed hose should be replaced with new
hose. Cut to length and install in the original routing.
Trim the hose winding shorter than the hose to allow
hose clamps to be fitted. Air valves that are defective
should be repaired or replaced. Check for proper operation and correct rigging of the valves after repair
or replacement.

TROUBLE SHOOTING.
15-7.

15-4. 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, air valves or controls can be
freed by proper lubrication. Damaged or broken
parts should be repaired or replaced. When checking rigging of controls, be sure 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 heater hoses
are properly secured and replace hoses that are
burned, frayed, or crushed. If fumes are detected
in the cabin, a very thorough inspection of the exhaust stacks and heater muffs should be accomplished.
Refer to paragraph 12-101 for this inspection. Since
any holes or cracks may permit exhaust fumes to
enter the cabin, replacement of defective parts is
imperative because the fumes constitute an extreme
danger. Seal any gaps in heater ducts across the

CABIN AIR VENTS.

15-8. Overhead cabin ventilation is provided by
manually adjustable ventilators installed on each
side of the cabin near the upper corners of the windshield. Air is received from scoops mounted in the
inboard wing leading edges. Formed elbows and
ducts deliver ram air to the ventilator assemblies,
which are adjustable to regulate the amount and
direction of air emitted into the cabin. Rear seat
overhead ventilators are installed in some airplanes.
The rear seat ventilator installation employs additional air inlets, ducting, and adjustable overhead
outlets.
15-9. An adjustable fresh air scoop door is provided on the forward right side of the fuselage of
some airplanes. Air entering this door is routed
to the duct across the aft side of the firewall for
blending with heated air or for distribution as cold
air into the cabin.
15-1

THRU SERIAL

1.
2.
3.
4.
5.
6.

Heat Control
Valve
Hose (Shroud-to-Baffle)
Hose (Valve-to-Shroud)
Nut
Washer

7.
8.
9.
10.
11.

Screw
Clamp
Clamp Bolt
Housing
Cotter Pin

PRIOR TO MODEL 150G

Figure 15-1.
15-2

Model 150 Heating and Ventilating System

12. Cylinder
13. Bearing
14. Plate
15. Bolt
16. Plate
17. Deflector

8.
9.
10.
11.
12.
13.
14.

Hinge Pin
Fuselage Skin
Seal
Doubler
Retainer
Firewall
Access Plate

15.
16.
17.
18.
19.
20.
21.

............. -.

* SER-AL 15066633 & ON
* 1968 MODEL 150H & ON
1. Cabin Heat Control
2. Defroster Hose
3. Cabin Air Control
4. Heater Hose
5. Inlet Hose
6. Air Scoop
7. Scoop Door

.. .......

':'"":"

SEE FIGURE

Defroster Nozzle
Clamp
Adapter
Deflector
Retainer
Insert
Retainer

22.
23.
24.
25.
26.
27.
28.

Defroster Outlet
Plate
Cylinder
Spacer
Housing
Plenum Chamber
Clamp

MODEL 150G & ON

Figure 15-2.

Model 150 Heating and Ventilating System
28

2127

15-3
15-3

1.
2.
Plenum
4.
5.
6.
7.
8.
9.

11.
12.

Defroster Outlet
Defroster Hose
3. Chamber
Left Exhaust Muffler
Right Exhaust Muffler
Air Scoop
Inlet Hose
Induction Air Hose
Heater Hose
Fitting
"Y"
10.
Heater Hose
Tee Fitting

13.

Cabin Heat Control

14.

Cabin Air Control

1968 MODEL 150H

Figure 15-2A. Heating and Defrosting System (Winterization Kit Installed)
* Flexible ducts replace
metal ducts beginning
with Model 172G.

fresh

wing

root
air

for

15-6

figure

See
vents and rear seat fresh air vents.
1.
2.
3.
4.
5.

Clamp
Hose
Warm Air Valve
Cabin Heat Control
Duct

6. Valve Body 12. Nut
7. Valve Plate 13. Washer
14. Clamp
8. Shim
9. Valve Seat 15. Spring
16. Cabin Air Control
10. Roll Pin
11. Arm

Figure 15-3. Models 172 and P172 Heating and Ventilating System
15-4

1968 MODEL 1721

Figure 15-3A.

Model 172 Heating and Defrosting System
15-4A/15-4B

PRIOR TO 1966

1966 & ON
2
21-

~NOTE

See figure 15-6 for wing root fresh air
vents and rear seat fresh air vents.

1966 & ON

13
12
SEE FIGURE 15-6

PRIOR TO 1966
15

1.
2.
3.
4.
5.
6.

Defroster Hose
Clamp
Nozzle
Valve
Knob
Guide

7.
8.
9.
10.
11.
12.

Duct Assembly
Seat
Roll Pin
Arm
Spring
Valve Plate

13. Body Assembly
14. Heater Hose
15. Duct Assembly
16. Cabin Heat Control
17. Outlets
18. Air Vent Control

Figure 15-4. Models 180 and 185 Heating and Ventilating System
15-5

* Retainer (14) and deflector (15)
are used on earlier models.
Deflector (17) is used on later

1965

*14

ON1965

models.

17'

415

See figure 15-6 for wing root fresh air
vents and rear seat fresh air vents.
1.
2.
3.
4.
5.
6.
7.
8.
9.

Cabin Heat Control
Nut
Washer
Arm
Roll Pin
Clamp Bolt
Spring
Valve Plate Assembly
Valve Seat

10.
11.
12.
13.
14.
15.
16.
17.

Shim
Valve Body
Clamp
Hose
Retainer
Deflector
Screw
Deflector

18.
19.
20.
21.
22.
23.
24.
25.
26.

Figure 15-5. Model 182 Heating and Ventilating System
15-6

Upholstery
Cowl Deck
Nozzle
Cotter Pin
Valve
Shaft
Defroster Control
Knob
Duct

TYPICAL ALL MODELS
PRIOR TO 1967

NOTE
models in place of hoses.

10.

Washer

Figure 15-6.

Valve

15.

Adapter

Ventilating System Details (Sheet 1 of 2)
15-7

TYPICAL IF USED

NOTE
<^

Tighten nut (9) securely, and cement

1967 & ON

to plate (11) with an epoxy base ad-

hesive. Dome (8) ia sealed to body
(19) at final assembly with an epoxy
base adhesive.

1.
2.
3.
4.
5.
6.
7.
8.
9.

Adapter
Hose Clamp
Tube
Clamp
Flexible Hose
Bracket
Silencer Assembly
Dome
Nut

10.
11.
12.
13.
14.
15.
16.
17.
18.
19.

Star Washer
Plate
Seal
Cap
Spring
Washer
Shaft
Spacer
Insulator
Valve Body

Figure 15-6. Ventilating System Details (Sheet 2 of 2)
15-8
15-8

20. Escutcheon
21. Directional Knob
22. Volume Knob
23. Setscrew
24. Inlet
25. Seal
26. Clamp Bolt
27. Air Vent Door
28. Cabin Air Control

15-10. OXYGEN SYSTEM.
15-11. Oxygen systems contain an oxygen cylinder,
oxygen lines, a pressure gage, an automatic constantflow regulator, outlets, and mask and line assemblies.
Oxygen cylinders are mounted aft of the baggage
compartment. Prior to 1965, the regulator, pressure
gage, and outlet assembly was located in the cabin
ceiling and contained a manifold with either four outlets (Model 182) or five outlets (Models 180 and 185).
Beginning in 1965, the regulator is installed in the
oxygen cylinder and is equipped with an ON-OFF
valve operated manually by a push-pull control
located above and to the left of the pilot. Location of
pressure gages, filler valves and other components,
and oxygen line routing variations are shown in figures 15-7 thru 15-9. The pilot receives a greater
flow of oxygen than the passengers. Beginning in
1966, the pilot's mask is equipped with a microphone
that is keyed by a switch button on the pilot's control
wheel on the Model 182.

WARNING
Oil, grease, or other lubricants in contact
with high-pressure oxygen create a serious
fire hazard, and such contact must be avoided.
Do not permit smoking or open flame in or
near airplane while work is performed on
oxygen system.
15-12. MAINTENANCE PRECAUTIONS.
a. Working area, tools, and hands must be clean.
b. Keep oil, grease, water, dirt, dust, and all
other foreign matter from system.
c. Keep all lines dry and capped until installed,
d. All compounds used on fittings must conform to
MIL-C-5542. No compound shall be used on aluminum alloy flared fittings. Compounds are used only
on the first three threads of the male threads. No
compound is used on coupling sleeves, or outside of
tube flares.
e. Fabrication of pressure lines is not recommended. Lines should be replaced by part number.
f. Lines and fittings must be clean and dry. One
of the following methods may be used:
1. Clean with a vapor degreasing solution of
stabilized trichlorethylene conforming to MIL-T-7003.
Follow by blowing lines clean and dry with clean, dry,
filtered air.
CAUTION
Most air compressors are oil lubricated, and
a minute amount of oil may be carried by the
air stream. A water lubricated compressor
should be used to blow tubing clean.
2. Flush with naptha conforming with Specification TT-N-95, then blow clean and dry with clean,
dry, filtered air. Flush with anti-icing fluid conforming to MIL-F-5566 or anhydrous ethyl alcohol.
Rinse thoroughly with fresh water and dry with clean,
dry, filtered air.
3. Flush with hot inhibited alkaline cleaner until
free from oil and grease. Rinse with fresh water
and dry with clean, dry, filtered air.

NOTE
Cap lines at both ends immediately after drying to prevent contamination.
15-13. REPLACEMENT OF COMPONENTS (PRIOR
TO 1965). Removal, disassembly, assembly, and
installation of components may be accomplished while
using figure 15-7 as a guide.

The pressure regulator, pressure gage, pressure lines, and filler valve should be removed
and replaced only by persons familiar with
high-pressure fittings. Observe the maintenance precautions listed in the preceding paragraph.
NOTE
Oxygen cylinder and regulator assemblies may
not always be installed in the field exactly as
illustrated in figure 15-7, which shows factory
installations. Important points to remember
are these:
The vent hole in the regulator body must not
be covered by the control clamp installed
around the regulator body.
The low pressure relief valve should not be
removed from the regulator except for replacement; it is installed in a specific port
only. Although the other three low pressure
ports are common to each other, the low pressure relief valve port is not.
The high pressure relief valve should not be
removed from the regulator except for replacement. Although all high pressure ports
are common to each other, the thread size is
different for the high pressure relief valve.
a. Before removing cylinder, release oxygen pressure, then disconnect filler line and outlet line from
cylinder. Cap all openings immediately.
b. To replace filler valve O-rings, first release
oxygen pressure. Disconnect chain but do not remove
cap from filler valve. Remove baggage compartment
rear wall or cover plate as required for access. Remove screws securing valve, disconnect pressure
line, and cap line and seat. Disassemble, replace
O-rings, reassemble, and install.
c. To replace valve core in manifold outlets, refer
to step "c" of paragraph 15-14. Similar, although not
identical, parts are installed in the manifold and the
precautions noted must be observed.
d. To remove the regulator, pressure gage, and
outlet assembly, first release oxygen pressure. The
headliner must then be lowered and soundproofing
removed. Refer to Section 3 for headliner removal.
15-14. REPLACEMENT OF COMPONENTS (1965
AND ON). Removal, disassembly, assembly, and
installation of components may be accomplished
while using figures 15-8 and 15-9 as guides.
15-9

MODEL 182 ROUTING

1.
2.
3.
4.

Pressure Gage
Regulator
Outlet Manifold
Cylinder

5.
6.
7.
8.
9.

Filler Valve
Access Door
Tee
Mask Assembly
Seat

10.
11.
12.
13.

Figure 15-7. Models 182, 180, and 185 Oxygen Systems (Prior to 1965)
15-10

Piston
O-Rings
Valve
Escutcheon

QUICK-DISCONNECT
VALVE

MICROPHONE CABLE
(1966 & on) Refer to
figure 6-4 for transmittern
switch button mounted in
control wheel

APPLY LOCTITE,
GRADE C
11

TO GAGE
2

TO GAGE

OUTLETSOU

TO FILLER

-TOFILLER VALVE

...............

MODEL 182L

.........--

PILOT'S OXYGEN MASK

.-..-

21j~x

1. Base

Lock Ring

16.

Valve

Low Pressure Relief Valve

17.

Cap

Jamb Nut

3.
4.
5.
6.

Spring
Poppet
Core
Escutcheon

10.
11.
12.
13.

Regulator
"On-Off" Control Cable
Pressure Gage
Seat

18.
19.
20.
21.

Baggage Wall
Escutcheon
Cover
Bracket

Cover

14.

Piston

22.

High Pressure Relief Valve

Figure 15-8.

Model 182 Oxygen System (1965 & on)
15-11

Beginning in 1968, the highpressure lines route to a
quick-disconnect valve on
the regulator. This valve
permits the cylinder to be
removed or installed in a
charged condition.

GAGE

1. Base
2. Jamb Nut
3. Spring
4. Poppet
5. Core
6. Escutcheon
7. Cover
10.

\\OUTLETS 15.
16.
1! TO FRONT OUTLETS

Figure 15-9.
15-12

19.

Line

Filler Valve
High Pressure Relief Valve

Oxygen Mask

Models 180 and 185 Oxygen System (1965 & on)

CAUTION
The pressure regulator, pressure gage,
pressure lines, and filler valve should be
removed and replaced only by persons familiar with high-pressure fittings. Observe the
maintenance precautions listed in paragraph
15-12.
NOTE
Oxygen cylinder and regulator assemblies may
not always be installed in the field exactly as
illustrated in figures 15-8 and 15-9, which
show factory installations.
Important points
to remember are these:
The vent hole in the regulator body must not
be covered by the control clamp installed
around the regulator body.
The low pressure relief valve should not be
removed
except for
the regulator
regulator except
for rereremoved from
from the
placement; it is installed in a specific port
only. Although the other three low press

overhauled by an FAA approved facility every five
years.
c. Pressure Gage. The pressure gage shall be
checked for accuracy and cleaned by an FAA approved facility every five years.
d. Individual Outlets. Each outlet shall be disassembled and inspected, and the sealing core replaced regardless of condition, every five years.
e. Filler Valve. The filler valve shall be disassembled and inspected, and the O-rings replaced
regardless of condition, every five years.
f. Filler Valve (Models 180 and 185, 1966 and on).
The filler valve is a part of the regulator assembly
noted in step "b. "
g. System Leak Test. With 200 to 500 psi on gage,
check entire system for leaks, using leak detector
compounded for use with oxygen systems. With
system under full pressure, repeat leak test on
high-pressure lines and fittings. Perform a complete leak test at least every five years. When
components are removed and replaced, leak test
applicable connections. After the test has been completeddste
wash Puging
away all traces
of thecomponents
leak detector.
have
Whenever
been removed and replaced, plug masks into all
outlets and purge the system for 10 minutes. Smell

ports are common to each other, the low pres-

oxygen flowing from outlets and continue to purge

sure relief valve port is not.

until odorless. Refill cylinder as required during
and after purging.

The high pressure relief valve should not begg
removed from the regulator except for replacement. Although all high pressure ports
are common to each other, the thread size is
different for the high pressure relief valve,
a. Before removing cylinder, release oxygen pressure, then disconnect push-pull control cable, filler
line on Model 182, pressure gage line, and outlet line
from regulator. Cap all lines immediately.
b. To replace filler valve O-rings in the Model 182,
release oxygen pressure, then disconnect chain but
do not remove cap from filler valve. Remove aft
baggage compartment wall. Remove screws securing valve and disconnect pressure line. Cap line and
seat. Disassemble, replace O-rings, reassemble,
and install. The filler valve is a part of the regulator assembly on Models 180 and 185 (1965 and on).
Replace the entire filler valve on these models.
c. To replace valve core (5) in outlets, unscrew
core with a suitable tool that will engage lugs protruding at each side of core. When installing the
core, be sure that poppet (4) is in place in spring
and that other end of poppet enters center of core.
If these parts are not positioned properly, the outlet
will not operate properly.NOTE
d. To remove the entire oxygen system, the headliner must be lowered and soundproofing removed to
expose lines. Refer to Section 3 for headliner re-

15-15A. FUNCTIONAL TEST. Whenever the oxygen
system regulator (or regulator and cylinder assembly) has been replaced or overhauled, perform the
following flow and internal leakage tests to check that

the system functions properly.

a. Fully charge the oxygen system per paragraph
15-16.
b. Install an oxygen outlet adapter (Cessna Part
Number C166005-0506) into a pressure gage (gage
should be calibrated in one-pound increments from
0 to 100 PSI), and insert adapter into an oxygen outlet. Place control lever in the "ON" position. The
gage pressure should be 75 ± 10 PSI.
c. Insert adapters (or mask and line assemblies if
they are operating properly) into all remaining outlets. With oxygen flowing from all outlets, the pressure should still be 75 ± 10 PSI.
d. Place oxygen control lever in the "OFF" position and allow pressure to fall to 0 PSI. Remove all
adapter assemblies except the one with the pressure
gage. The pressure must not rise above 0 PSI when
observed for one minute. Remove pressure gage and
adapter from oxygen outlet.

If pressures specified in the foregoing procedures are not obtained, the oxygen regulator

is not operating properly.

moval.

15-15. INSPECTION REQUIREMENTS.
a. ICC 3AA 1800 Oxygen Cylinder. This cylinder

shall be hydrostatically tested to 5/3 working pressure every five years by an FAA approved facility.
The month and year of the latest test is stamped

near the neck of the cylinder.

This date should also

be recorded in the aircraft log book.turn
b. Regulator. The regulator shall be removed and

Remove and re-

place cylinder and regulator assembly with
another unit and repeat test procedure.

Connect oxygen masks to each outlet and check

each mask for proper operation.
Check proper function of plot's mask micro-

phone and control wheel switch.

After checking, re-

all masks to mask case.
g. Recharge oxygen system as required.
15-13

allow pressure to equalize, then close cascade cylinder valve.
c. Repeat this procedure, using a progressively
higher pressure cascade cylinder, until system has
been charged to the pressure indicated in the following chart.
d. This chart automatically compensates for temperature rise as a result of compression. Ambient
temperature listed in the chart is the air temperature
in the area where the system is to be charged. Approach the chart filling pressures slowly and do not
overcharge.

15-16. CHARGING. Do not charge oxygen systems
if fittings on servicing equipment or filler valve are
corroded or contaminated. If in doubt, clean with
stabilized trichlorethylene and let air dry. Do not
permit solution to enter internal parts. Before
charging, check the hydrostatic test date as noted
in paragraph 15-15, step "a."
CAUTION
Do not charge an oxygen cylinder if it has become contaminated. The regulator and cylinder assembly must then be disassembled, inspected, and cleaned by an FAA approved
facility before filling. Contamination, as used
here,-means-dirt- dust-,or-other-foreignmratter, as well as ordinary air in large quantities.
If a gage line or filler line is disconnected and
fittings capped immediately, the cylinder will
not become contaminated unless temperature
variation has created a suction within the cylinder. Likewise, a regulator may be replaced
without contaminating the cylinder, if the same
conditions are observed. Ordinary air contains
water vapor which could condense and freeze.
Since there are very small orifices in the system, it is important that this not be permitted
to occur.

TABLE OF FILLING PRESSURES
Ambient
Temp.
°F

Filling
Press
psig

Ambient
Temp.
°F

Filling
Press.
psig

0
10
20
30
40

1600
1650
1700
1725
1775

50
60
70
80
90

1825
1875
1925
1975
2000

15-17. CLEANING OXYGEN MASKS. Oxygen masks
may be washed and cleaned in household detergenttype solutions. However, the radio microphone installed in some pilot's masks must either be removed
or protected from moisture. Masks may be disinfected with a hospital-type antiseptic spray (Zep
Aero SBT-12, or equivalent).

a. Connect cascade connection to filler valve.
b. Slowly open valve on cascade cylinder with
lowest pressure, as noted on cascade pressure gage,
NOTE

Each interconnected series of oxygen cylinders is equipped with a single gage. The trailer type
cascade may also be equipped with a nitrogen cylinder (shown reversed) for filling landing gear
struts, accumulators, etc. Cylinders are not available for direct purchase, but are usually
leased and refilled by a local compressed gas supplier.
Service Kit SK310-32 (available from the Cessna Service Parts Center) contains an adapter, a
pressure gage, hose, lines, and fittings for equipping two oxygen cylinders to service oxygen
systems. As noted in the Service Kit, a tee (Part No. 11844) and a pigtail (Part No. 1243-2)
should be ordered for each additional cylinder to be used in the cascade of cylinders. Be sure
to ground the airplane and ground servicing equipment before use.
OXYGEN CYLINDER
-NITROGEN CYLINDER
PRESSURE GAGE

OXYGEN PURIFIER-

W/REPLACEABLE
CARTRIDGE

Figure 15-10.
15-14

Typical Portable Oxygen Cascades

SECTION 16
INSTRUMENTS AND INSTRUMENT SYSTEMS
TABLE OF CONTENTS
G EN ERA L..............................................................
INSTRUMENT PANELS ......................................
Removal ........................................
Adding Extra Shock Mounts .............................
Installation ........................................
Instrument Removal ........................................
Instrument Installation ......................................
PITOT AND STATIC SYSTEMS ...........................
True Airspeed Indicator ....................................
Trouble Shooting - Pitot Static System............
Trouble Shooting - Airspeed Indicator ............
Trouble Shooting - Altimeter............................
Trouble Shooting - Vertical Speed Indicator....
Trouble Shooting - Heated Pitot Head ............
Pitot and Static System Maintenance ..............
Aligning Pitot Tube ........................................
Checking Pitot System for Leaks .....................
Static Pressure System Inspection and
Leakage Test ....................................
Blowing Out Pitot Lines ....................................
Removal of Pitot and Static Pressure System .
Replacement of Pitot and Static Pressure
System....................
..........
VACUUM SYSTEMS ........................................
Trouble Shooting - Vacuum Systems..............
Trouble Shooting - Gyros ................................
Trouble Shooting - Vacuum Pump ..................
Trouble Shooting - Vacuum Switch .................
Vacuum System Removal ................................
Vacuum System Replacement .........................
Vacuum System Cleaning ................................
Suction Gage Readings ...................................
ENGINE INDICATORS ...................................
Tachometer ........................................
Manifold Pressure Gage...................................
Trouble Shooting - Manifold Pressure Gage...
Cylinder Head Temperature Gages .................
Trouble Shooting - Cylinder Head
Temperature Gages ........................................
Cylinder Head Temperature Gage
Maintenance.....................................................

Page
16-1
16-2
16-2
16-2
16-2
16-6
16-6
16-6
16-6A
16-7
16-7
16-8
16-9
16-9
16-11
16-11
16-11
16-11
16-15
16-15
16-15
16-16
16-16
16-17
16-18
16-19
16-19
16-19
16-19
16-19
16-27
16-27
16-27
16-27
16-28
16-29
16-30

Page
Oil Pressure Gage..................................... 16-30
Trouble Shooting - Oil Pressure Gage
(Direct Reading)......................................... 16-30
Oil Temperature Gage .
..............................
16-31
Carburetor Air Temperature Gages ........... 16-31
Trouble Shooting - Carburetor Air
Temperature Gage (Electric) . ....................16-32
FUEL QUANTITY INDICATORS .....................
16-33
Trouble Shooting - Fuel Quantity
Indicators (Electric) .................................... 16-33
TRANSMITTER ADJUSTMENT . ....................16-34
Stewart Warner Gage Transmitter
Calibration .......................................
16-34
Rochester Fuel Gage Transmitter.............. 16-34
Fuel Quantity Indicating System
Operational Test......................................... 16-34
Cylinder Head Temperature Indicating
System Resistance .................................... 16-34A
Oil Temperature Indicating System
Resistance................................................. 16-34B
Fuel Flow Indicator..................................... 16-34C
Trouble Shooting - Fuel Flow Indicator..... 16-34C
MAGNETIC COMPASS .
.................................
16-34D
STALL WARNING HORN AND
TRANSMITTER...............................................
16-37
PNEUMATIC STALL WARNING HORN......... 16-37
TURN-AND-BANK INDICATOR...................... 16-38
Trouble Shooting - Turn-and-Bank
Indicator ........................................
16-39
TURN COORDINATOR .
................................
16-39
Trouble Shooting ........................................ 16-39
ELECTRIC CLOCK ........................................ 16-39
HOURMETER ........................................
16-39
CESSNA ECONOMY MIXTURE INDICATOR
Trouble Shooting ........................................ 16-39
Calibration ........................................
16-39
Removal and Installation............................ 16-40
WING FLAP POSITION INDICATING
SYSTEM ...................................................... 16-40
Trouble Shooting Flap Indication System.. 16-40
WING LEVELER ............................................. 16-41
Rigging ....................................................... 16-41

16-1.

GENERAL.

16-2.

This section describes typical instrument installations and the systems operating them, with
emphasis on trouble shooting and corrective measures for the systems themselves. It does not deal
with specific instrument repairs since this usually requires special equipment and data and should be
handled by instrument specialists. Federal Aviation Regulations require that malfunctioning
instruments be sent to an approved instrument overhaul and repair station or returned to the
manufacturer for servicing. Our concern here is with preventative maintenance on the various
instrument systems and correction of system faults which result in instrument malfunctions.
The descriptive material, maintenance, and trouble shooting information in this section is intended to
help the mechanic determine malfunctions, and correct them, up to the defective instrument itself, at
which point the instrument technician should be called in.

Revision 1
©Cessna Aircraft Company

16-1
Aug 4/2003

Some instruments, such as fuel quantity and oil pressure gages, are so simple and inexpensive that
repairs usually will be more costly than a new instrument; on the other hand, aneroid and gyro
instruments usually are well worth repairing. The words "replace instrument" in the text, therefore,
should be taken only in the sense of physical replacement in the airplane. Whether the replacement
is to be with a new instrument, an exchanged one, or the original instrument is to be repaired must
be decided on the basis of individual circumstances.
16-3.

INSTRUMENT PANELS. (See figure 16-1.)

16-4.

Instrument panels in Cessna aircraft are made in two main sections: the stationary panel, which
carries switches and controls and contains instruments such as fuel quantity and oil pressure and
temperature gages, which are not sensitive to vibration, and the shock-mounted panel which carries
the major flight instruments. Most of the instruments are screw-mounted on the backs of the shockmounted panels, which in turn are covered with metal or molded plastic decorative panels.

16-5.

REMOVAL.
The stationary instrument panels are secured to the engine mount stringers and a forward fuselage
bulkhead and ordinarily are not considered removable. The shock-mounted panels are secured to
the stationary panels by rubber shock mount assemblies.

16-6.

To remove the shock-mounted panel, release the clips securing the decorative panel by carefully
prying under the buttons on the clips. Remove any control knobs or lock nuts on the panel
which would interfere and pull off the cover. Remove the nuts from the shock mount screws,
tag, and disconnect the instrument plumbing and wiring and pull the panel straight back. If it
should become necessary to remove the shock-mounted panel and its decorative cover from the
airplane, on some aircraft, the control where shaft and wheel must first be removed. This is
done by removing the nuts and bolts securing the shaft to the control wheel universal on the
control tee. On Model 182 aircraft, the control wheel can be removed from the control shaft by
removing securing screws, thereby permitting removal of the shock panel with the control shaft
installed.

Where shock mount assemblies (12) are used, the bolts securing the panel to the shock mounts
must be removed. Note the combination of bolts, washers, ground straps and spacers used on
each mount for correct replacement when the panel is reinstalled.

ADDING EXTRA SHOCK MOUNTS.
Service life of instruments is directly related to adequate shock-mounting of the panel. In some
cases, particularly when additional instruments have been added in the field, the original shock
mounts are inadequate to support the increased weight of the panel. Installing additional shock
mounts, when the instrument complement is increased, is a practical fix to prevent rapid
deterioration of the mounts at the original locations.

16-7.

INSTALLATION.
a.

To install the shock-mounted panel, set it in place in the stationary panel, aligning the shock
mounts with the holes in the panel, and install the nuts on the shock mount screws.

To install the shock-mounted panel where shock mount assemblies (12) are used, place the
panel mounting screws and spacers in their proper positions, then position the panel, insert the
screws in the mounts, and install the nuts.

Replace the instruments and connect the wiring and plumbing. Position the decorative cover
and press the retainer clips through the holes in the panel. A light coat of paraffin, beeswax, or
soap on the prongs of the retainer clips will make their insertion easier.

16-2

Revision 1
Cessna Aircraft Company

Aug 4/2003

NOTE

B1940

This is a typical shock-mounted instrument
panel. The panels used in the various models
differ in configuration however, all are simliar in method of attachment
Two types of
shock mounts are used in Cessna airplanes,

and the same type should be usd whenever
replacement is necessary.
The shock-mounted panel in the Model 182L
carries only the gyro instruments. When

removing the panel, note sequence of attach-

ing parts and location of ground straps to aid
installation

1.
2.
3
4.
5.
6.
7.

9.
10.
11.
13.
13.
14.

Fastener
Decorative Cover
Compass Card Holder
Shock-Mounted Panel
Nut
Spacer
Lockwsher
Shock
Mount
Ground Strap
Screws
Spacer
Shock Mount
Washer
Nuts

NOTE
If shock mount (8) has unequal
thread length, install shorter
threads through stationary panel.
The direction of screws (10)

is reversed on some aircraft.
Note direction upon removal.

Figure 16-1. Typical Shock-Mounted Panel

16-3

Revision 1
© Cessna Aircraft Company

Aug 4/2003

B1983

TYPICAL OF MODELS 180, 182 & 185

Line (Right Sump to Tee)

12.
13.

2. Right Static Source Sump

14. Stem (Pitot Mast)

15.

Elbow

4. Nipple

22. Tee
23. Line (Airspeed Indicator Tee to

Body (Pitot Mast)
Tube (Pitot Mast)

Altimeter Tee)

Nose Fitting (Pitot Mast)

24. Line (Altimeter Tee to Vertical

16. Heater Assembly (Pitot Mast)

5. Right Static Port
17.
6. Line (Airspeed Indicator to 18.
Union in Wing)

Speed Indicator Tee)

Airspeed Indicator
25. Tee
Line (Tee to Left Sttic Source 26. Vertical Speed Indicator
Sump)
27. Swtch(Pitot Heater)

P172

1. Switch (Pitot Heater)
2. Line (Airspeed Indicator to Union
in Wing)
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.

Union
Line (Pitot Tube to Wing Root)
Union
Line (Union to Heated Pitot Tube)
Connector (Pitot Tube)
Screw
Pitot Tube Mast Assy (Heated)
Heater Element (Pitot Mast)
Pitot Tube (Unheated)
Static Port

13. Nipple
14.
15.

Elbow
Static Source Sump
16. Line (Static Source to Airspeed

Indicator)
NOTE
The model P172 has two static
ports; one on either side of the
tailcone.

Figure 16-2. Pitot-Static Systems

16-4
© Cessna Aircraft Company

Revision 1
Aug 4/2003

B1966

TO INSTRUMENTS

1. Insert
2. Tee
3.
4.
5.
6.

7.
8. Clamp

9. Coupling
10. Connector
TYPICAL INSTALLATION
ALL MODELS EXCEPT 150

Figure 16-2A. Alternate Static Air Source

SHOP NOTES:

16-5

Revision 1
© Cessna Aircraft Company

Aug 4/2003

d. Install any previously removed control knobs and lock nuts. If the control wheel and control shaft
were previously removed for complete removal of the shock panel and decorative cover, insert the
control wheel and shaft through the shock-mounted panel and connect it to the universal on the
control tee. Reinstall the control wheel on Model 182 aircraft.
16-8.

INSTRUMENT REMOVAL.
Most instruments are secured to the panel with screws inserted through the panel face, under the
decorative cover. To remove and instrument, remove the decorative cover (if necessary), disconnect the
plumbing or wiring to the instrument concerned, remove the retainer screws and take the instrument out
from behind, or, in some cases, from the front of the instrument panel. Some instruments installed on the
stationary panel can be removed if desired without removing the decorative cover; the mounting screws
for these instruments have jam nuts so that the instrument retainer nuts may be removed and replaced
without holding the screw heads. Other instruments on the stationary panel are circumscribed with
escutcheons. Instrument mounting screws in the corners of the escutcheons are accessible on the face
of the panel; the retainer nuts are accessible from behind the instrument panel. The decorative cover
need not be removed to take out these instruments. The instrument cluster used on some models is
installed as a unit, secured by a screw on each end of the cluster. The cluster must be removed from the
panel to replace an individual gage.
NOTE: In some airplanes, the instrument cluster is located directly above the glove box. Removal of the
cluster will be simpler if the glove box is removed first. The box is attached with screws just
inside the box opening.
In all cases when an instrument is removed, the lines or wires disconnected from it should be protected.
Cap open lines and cover pressure connections on the instrument to prevent thread damage and the
entrance of foreign matter. Wire terminals should be insulated or tied up so they will not ground
accidentally, or short-circuit on another terminal.

16-9.

INSTRUMENT INSTALLATION.
Generally, installation procedure is the reverse of the removal procedure. Make sure that the mounting
screw nuts are tightened firmly, but to do not over-tighten them, particularly on instruments having plastic
cases. The same rule generally applies to connecting plumbing and wiring. If thread lubricant or sealer is
used on plumbing, it should be applied sparingly and only on the male threads. When replacing an
electrical gage in an instrument cluster assembly, avoid bending the pointer or dial plate. Distortion of the
dial or back plate could change calibration of the gages.

16-10. PITOT AND STATIC SYSTEMS
16-11. The pitot and static systems are systems of metal or plastic tubing which convey ram air pressure and
atmospheric pressure to the airspeed and vertical speed indicators and the altimeter. Ram air pressure
picked up by the pitot tube on the leading edge of the left wing is transmitted to the airspeed indicator by
tubing running through the wing leading edge to the cabin, then down the left forward doorpost and
forward to the instrument panel. Atmospheric pressure for the airspeed and vertical speed indicators and
the altimeter is picked up by static pressure ports on the fuselage and transmitted through tubing to the
instruments. Two general system layouts are used on Cessna single-engine airplanes. The 150 and 172
series have single static ports on the left side of the fuselage and a simple metal pitot tube projecting
down and forward from the left wing leading edge. The P172 system is identical except that it has two
static ports, one located on either side of the tailcone. All aircraft of these series have static line sumps to
collect condensation in the static system. The 180, 182, and 185 series use dual static ports, one on
each side of the fuselage. All of these aircraft also have a static line sump adjacent to the static port.
The pitot tubes in these series are enclosed in mast-type housings. An optional alternate static air source
(see figure 16-2A) may be installed for use in emergencies on all models except 150. When the alternate
static air valve is opened, cabin air pressure is substituted for atmospheric pressure, causing instrument
readings to vary from normal. Refer to Owner's Manual for flight operation using alternate static source
pressure. The alternate static air source valve is located beneath the left side of the instrument panel.
Pitot heat installations are optional equipment on some airplanes. On the 150,172, and P172 series,
pitot heat is available when the standard metal pitot tube is replaced with a mast-type pitot tube
containing a heating element. The mast-type tube is standard equipment on 180, 182, and 185 series,
16-6

Revision 1
© Cessna Aircraft Company

Aug 4/2003

and the addition of pitot heat to these aircraft is simply a matter of adding the heating element and the
necessary wiring. The pitot heater is powered by the airplane's electrical system and controlled by a
switch on the instrument panel. The pitot and static line plumbing shown in figure 16-2 is a typical factory
installation. Several variations have been used in factory installations to accommodate optional
instrumentation and other variations have been made in the field while making custom installations.
However, the servicing and maintenance procedures given here will apply in general to all these
variations.
16-11A.TRUE AIRSPEED INDICATOR.
A true airspeed indicator may be installed as optional equipment on all 100-Series aircraft. The indicator
is equipped with a true airspeed conversion ring. The ring may be rotated until pressure altitude is
aligned with outside air temperature, then indicated airspeed on the gage is read as true airspeed on the
adjustable ring. The instrument may be removed using figure 16-2B as a guide. Upon installation, and
before tightening mounting screws (2), the instrument must be calibrated. This is accomplished as
follows: rotate ring (4) until 120 mph on the adjustable ring aligns with 120 mph on the indicator. Holding
this setting, move retainer (3) until 60° F. aligns with zero pressure altitude, then tighten mounting screws
(2) and replace decorative cover.
B1965

Do not
and do

NOTE
part
must

. In-

Indicator
4.

True Airspeed Ring

Nut

Figure 16-2B. True Airspeed Indicator

Revision 1
© Cessna Aircraft Company

16-6A/16-6B
Aug 4/2003

16-12.

TROUBLE SHOOTING--PITOT-STATIC SYSTEM.
ISOLATION PROCEDURE

PROBABLE CAUSE

REMEDY

LOW OR SLUGGISH AIRSPEED INDICATION.
Normal altimeter and vertical
speed - Pitot tube deformed,
leak or obstruction in pitot
line.

Check alignment, test line for leaks
or obstructions,

Straighten tube, repair or replace
damaged line.

INCORRECT OR SLUGGISH RESPONSE.
All three instruments - leaks
or obstruction in static line.
Alternate static source valve
open.

Test line for leaks and obstructions.
Check visually.

Repair or replace line.
Close for normal operation.

16-13. TROUBLE SHOOTING -- AIRSPEED INDICATOR.
PROBABLE CAUSE

REMEDY

ISOLATION PROCEDURE

HAND FAILS TO RESPOND.
Pitot pressure connection
not properly connected to pressure line from pitot tube.

Test line and connection for leaks.

Repair or replace damaged line,
tighten connections.

Pitot or static lines clogged.

Check line for obstructions.

Blow out lines.

INCORRECT INDICATION OR HAND OSCILLATES.
Leak in pitot or static lines.

Test lines and connections for
leaks.

Repair or replace damaged
lines, tighten connections.

Defective mechanism.

Substitute known-good indicator
and check reading.

Replace instrument.

Leaking diaphragm.

Substitute known-good indicator
and check reading.
Check visually.

Replace instrument.

Excessive vibration.

Check panel shock mounts.

Replace defective shock mounts.

Excessive tubing vibration.

Check clamps and line connections
for security,

Tighten clamps and connections,
replace tubing with flexible hose.

Alternate static source valve
open.

Close for normal operation.

HAND VIBRATES.

16-7

16-14. TROUBLE SHOOTING -- ALTIMETER.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

INSTRUMENT FAILS TO OPERATE.
Static line plugged.

Check line for obstructions.

Blow out lines.

Defective mechanism.

Substitute known-good altimeter
and check reading.

Replace instrument.

INCORRECT INDICATION.
Hands not carefully set.

Reset hands with knob.

Leaking diaphragm.

Substitute-known-good-altimeter
and check reading.

Replace instrument.

Pointers out of calibration.

Compare reading with knowngood altimeter.

Replace instrument.

Static pressure irregular.

Check lines for obstructions or
leaks.

Blow out lines, tighten connections.

Leak in airspeed or vertical
speed indicator installations.

Check other instruments and
system plumbing for leaks and
obstructions.

Blow out lines, tighten connections.

HAND OSCILLATES.

SHOP NOTES:

16-8

16-15. TROUBLE SHOOTING -- VERTICAL SPEED INDICATOR.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

INSTRUMENT FAILS TO OPERATE.
Static line plugged.

Check line for obstructions.

Blow out lines.

Static line broken.

Check line for damage, cannections for security.

Repair or replace damaged
line, tighten connections.

Partially plugged static line.

Check line for obstructions.

Blow out lines.

Ruptured diaphragm.

Substitute known-good Indicator and check reading.

Replace instrument.

Pointer off zero.

Reset pointer to zero.

INCORRECT INDICATION.

POINTER OSCILLATES.
Partially plugged static line.

Check line for obstructions.

Blow out lines.

Leak in static line.

Test lines and connections for
leaks.

Repair or replace damaged lines,
tighten connections.

Leak in instrument case.

Substitute known-good indicator
and check reading.

Replace instrument.

Excessive vibration.

Check shock mounts.

Replace defective shock mounts.

Defective diaphragm.

Substitute known-good indicator
and check for vibration.

Replace instrument.

HAND VIBRATES.

16-16. TROUBLE SHOOTING -- HEATED PITOT HEAD.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

TUBE DOES NOT HEAT OR CLEAR ICE.
Switch turned "OFF."

Turn switch "ON."

Blown fuse or circuit breaker.

Check fuse or circuit breaker.

Replace or reset.

Break in wiring.

Test for open circuit.

Repair wiring.

Heating element burned out.

Check resistance of heating
element.

Replace element.

16-9

NOTE
Air bulb with check valves may be obtained
locally from a surgical supply company. This
is the type used in measuring blood pressure.

THICK-WALLED
SURGICAL HOSE

PRESSURE
PRESSURE

PRESSURE BLEED-OFF
SCREW (CLOSED)
AIR BULB
WITH CHECK--VALVES

CLAMP
CLAMP

THICK-WALLED
SURGICAL HOSE

SUCTION

CHECK VALVE

TO APPLY SUCTION:
1.

Squeeze air bulb to expel as much air as possible.

Hold suction hose firmly against static pressure source opening.

Slowly release air bulb to obtain desired suction, then pinch hose shut tightly to trap suction in
system.

After leak test, release suction slowly by intermittently allowing a small amount of air to enter
static system. To do this, tilt end of suction hose away from opening, then immediately tilt it
back against opening. Wait until vertical speed indicator approaches zero, then repeat. Continue to admit this small amount of air intermittently until all suction is released, then remove
test equipment.

TO APPLY PRESSURE:
(CAUTION
Do not apply positive pressure with airspeed indicator or vertical speed
indicator connected into static system.
1.

Hold pressure hose firmly against static pressure source opening.

Slowly squeeze air bulb to apply desired pressure to static system. Desired pressure may be
maintained by repeatedly squeezing bulb to replace any air escaping through leaks.

Release pressure by slowly opening pressure bleed-off screw, then remove test equipment.

Figure 16-2C.
16-10

Static System Test Equipment

16-17. PITOT AND STATIC SYSTEM MAINTENANCE.
Proper maintenance of the pitot and static system is
essential for the proper operation of the altimeter,
and vertical speed and airspeed indicators. Leaks,
moisture and obstructions in the pitot system will
result in false airspeed indications, while static syster malfunctions will affect the readings of all three
instruments. Under instrument flight conditions,
these instrument errors could be hazardous. Cleanliness and security are the principal rules for pitot
and static pressure system maintenance. Both the
pitot tube and the static ports must be kept clean and
unobstructed.
16-18. ALIGNING PITOT TUBE. For correct airspeed indication the pitot tube on the 150, 172, and
P172 series must be properly aligned, so the open
end of the tube is perpendicular to the vertical axis
and parallel to the longitudinal axis of the airplane.
For the P172 and 172 (prior to 1967), a template
like the one shown in figure 16-3 will prove the most
convenient means of checking this alignment. Prior
to using the templates, check that the pitot tube
parallels the row of rivets just outboard of the tube.
A straightedge may be placed along the row of rivets
to check alignment. Tube alignment on Model 150
(prior to 1967) should be checked with a template
made to the pattern in figure 16-4. The template
shown in figure 16-4A is used to align the pitot tubes
on both Models 150 and 172 (1967 and on). All templates fit over the wing leading edge and the pitot
tube should conform to the illustration. The illustrations have been drawn carefully to actual size so
they may be traced directly on a sheet of stiff plastic,
plywood, or metal. Place a piece of carbon paper
between the printed page and the template material,
then trace the contours.
16-19. CHECKING PITOT SYSTEM FOR LEAKS. To
check the pitot system for leaks, fasten a piece of
rubber or plastic tubing over the pitot tube, close the
opposite end of the tubing and slowly roll up the tube
until the airspeed indicator registers in the cruise
range. Secure the tube and after a few minutes recheck the airspeed indicator. Any leakage will have
reduced the pressure in the system, resulting in a
lower airspeed indication. Slowly unroll the tubing
before removing it, so the pressure is reduced gradually. Otherwise the instrument may be damaged. If
the test reveals a leak in the system, check all connections for tightness. On some airplanes, the pitot
system includes a rubber hose connection at the wing
root rib. Pay particular attention to this connection
when checking the system for security; if the hose
shows signs of deterioration, replace it.
16-19A. STATIC PRESSURE SYSTEM INSPECTION
AND LEAKAGE TEST. The following procedure
outlines inspection and testing of the static pressure
system, assuming that the altimeter has been tested
and inspected in accordance with current Federal
Aviation Regulations.

a. Ensure that the static system is free from entrapped moisture and restrictions.
b. Ensure that no alterations or deformations of
the airframe surface have been made that would
affect the relationship between air pressure in the
static pressure system and true ambient static air
pressure for any flight configuration.
c. If dual static pressure sources are used, seal
off the opening in one with plastic tape. This must be
an air-tight seal.
d. Close the static pressure alternate source valve,
if installed.
e. Attach a source of suction to the remaining static
pressure source opening. Figure 16-2C shows one
method of obtaining suction.
f. Slowly apply suction until altimeter indicates a
1000-foot increase in altitude.
caution
When applying or releasing suction, do not
exceed the range of the vertical speed indicator or airspeed indicator.
g. Cut off the suction source to maintain a "closed"
system for one minute. Leakage shall not exceed
100 feet of altitude loss as indicated on altimeter.
h. If leakage rate is within tolerance, slowly release suction source, then remove tape if used to
seal static source on dual installations.
NOTE
If leakage rate exceeds the maximum allowable, first tighten all connections then repeat
the leakage test. If leakage rate still exceeds
the maximum allowable, use the following procedure.
i. Disconnect static pressure lines from airspeed
indicator and vertical speed indicator, and use suitable fittings to connect the lines together so that the
altimeter is the only instrument still connected into
the static pressure system.
j. Repeat the leakage test to check whether the
static pressure system or the removed instruments
are the cause of leakage. If instruments are at fault,
they must be repaired by an "appropriately rated repair station" or replaced. If the static pressure system is at fault, use the following procedure to locate
the leakage.
k. Attach a source of positive pressure to the
static source opening. Figure 16-2C shows one
method of obtaining positive pressure.

Do not apply positive pressure with the airspeed indicator or vertical speed indicator
connected to the static pressure system.
1. Slowly apply positive pressure until altimeter
indicates a 500-foot decrease in altitude, and main-

16-11

WING CONTOUR
(Cut out)

WING CONTOUR

(Cut out)

Pitot tube must parallel horizontal lines.

WCO

WING CONTOUR
(Cut out)

0CC

tain this altimeter indication while checking forleaks.
Coat line connections, static pressure alternate
source valve, and static source flange with solution
of mild soap and water, watching for bubbles to
locate leaks.
m. Tighten leaking connections. Repair or replace
any parts found defective.
n. Reconnect airspeed indicator and vertical speed
indicator into the static pressure system and repeat
leakage test per steps "c" thru "h. "
16-20. BLOWING OUT PITOT LINES. Although the
pitot system is designed to drain down to the pitot
tube opening, condensation may collect at other points
in the system and produce a partial obstruction. To
clear the line, disconnect it at the airspeed indicator
and, using low pressure air, blow from the indicator
end of the line toward the pitot tube.

Never blow through pitot or static lines toward
the instruments. Doing so may damage them.
Like the pitot lines, the static pressure lines must
be kept clear and the connections tight. All models
have static source sumps that collect moisture and
keep the system clear. However, when necessary,
disconnect the static line at the first instrument to
which it is connected, then blow the line clear with
low-pressure air.
NOTE
On aircraft equipped with alternate static
source, use the same procedure, opening
alternate static source valve momentarily
to clear its line, then close valve and clear
remainder of the system.

Check all static pressure line connections for tightness. If hoses or hose connections are used, check
them for general condition and their clamps for
security. Replace hoses which have cracked, hardened or show other signs of deterioration.
16-21. REMOVAL OF PITOT AND STATIC PRESSURE SYSTEM. To remove the pitot mast on models
with this type system, remove the four mounting
screws on the side of the attaching connector and pull
the mast out of the connector far enough to disconnect
the pitot line. Electrical connections to the heater
assembly (if installed) may be disconnected through
the wing access opening just inboard of the mast. On
airplanes having the simple metal pitot tube, the
tube connection is accessible through the access
hole just inboard of the pitot tube. To remove the
pitot tube, disconnect the fitting and pull the tube out
of the wing through the access hole. The pitot and
static lines are removed in the usual manner, after
removing the wing access openings, lower wing
fairing strip, decorative cover over the left doorpost, and when necessary, the left forward upholstery panel. Reinstallation of the wing line will be
simpler if a guide wire is drawn in as the line is removed from the wing. The wing line may be removed intact by drawing it out through the cabin and
right cabin door.
16-22. REPLACEMENT OF PITOT AND STATIC
PRESSURE SYSTEM. When replacing components of
the pitot and static pressure systems, use anti-seize
compound sparingly on the male threads on both
metal and plastic connections. Avoid excess compound which might enter the lines. Tighten connections firmly, but avoid overtightening and distorting the fittings. If twisting of plastic tubing is
encountered when tightening the fittings, VV-P-236
or USP Petrolatum may be applied sparingly between
the tubing and fittings.

SHOP NOTES:

16-15

16-23.

VACUUM SYSTEMS.

16-24. Suction to operate directional gyro and gyro
horizon instruments is provided by a single super
venturi system, or by an engine-driven vacuum pump.
Model 172 airplanes, except the Skyhawk, have no
provision for mounting a vacuum pump, therefore
these aircraft utilize a single venturi to provide suction. All other aircraft have vacuum pump provisions.
The engine-driven vacuum system uses a vacuum
pump mounted on the engine accessory case or the
engine case. The pump is gear-driven through a
spline-type coupling. The vacuum pump discharge
is through an oil separator, where the oil, which
passes through the pump and lubricates it, is returned to the engine sump and the air is expelled
overboard. The 1968 Model 172 and Skyhawk have
a dry vacuum pump that-utilizes-sealed-bearings
therefore deleting the need for an oil separator. The
16-25.

TROUBLE SHOOTING -- VACUUM SYSTEM.
PROBABLE CAUSE

venturi-type vacuum source is not required on the
1968 Model 172. A suction relief valve, used on
engine-driven vacuum pump systems, is used to control system pressure. It is connected between the
pump inlet and the instruments. In the cabin, the
vacuum line runs from the gyro instruments to a relief valve at the firewall, or to a relief valve and
through the side of the fuselage to a venturi. A central air filtering system is utilized in all vacuum
systems of 1965 & on aircraft. The reading of the
suction gage in the central filter system indicates net
difference in suction before and after air passes
through a gyro. This differential pressure will
gradually decrease as the central filter becomes
dirty, causing a lower reading on the suction gage.
Prior to 1965 the pictorial gyros are equipped with
warning lights to indicate abnormal suction, and do
not-utilize-a-suction-gage. A-test-switch providesa
means of checking the lights. The venturi for the
Model 172 vacuum system is located on the fuselage,
just forward of the right landing gear spring.
REMEDY

ISOLATION PROCEDURE

HIGH SUCTION GAGE READINGS.
Gyros function normally Relief valve screen clogged,
relief valve malfunction.

Check screen, then valve.
Compare gage readings with new
gage.

Clean screen, reset valve.
Replace gage.

NORMAL SUCTION GAGE READING, SLUGGISH OR ERRATIC GYRO RESPONSE.
Check operation with filters removed.

Replace filters.

Leaks or restriction between
instruments and relief valve,
relief valve out of adjustment,
defective pump or venturi, restriction in oil separator or
pump discharge line.

Check lines for leaks, check
pump discharge volume,
disconnect and test pump.

Repair or replace lines, adjust or
replace relief valve, repair or replace pump or venturi, clean oil
separator.

Central air filter dirty.

Check operation with filter removed.

Clean or replace filter.

Check suction with test gage.

Replace gage. Clean sticking valve
with Stoddard solvent. Blow dry
and test. If valve sticks after
cleaning, replace it.

Instrument air filters clogged.

LOW SUCTION GAGE READINGS.

SUCTION GAGE FLUCTUATES.
Defective gage or sticking
relief valve.

OIL COMES OVER IN PUMP DISCHARGE LINE.
Oil separator clogged, oil
return line obstructed, excessive oil flow through pump.

16-16

Check oil separator, return line.
Check that pump oil return rate
does not exceed 120 cc/hour
(approx. 8 drops/minute), at 50
psi oil pressure.

Clean oil separator in Stoddard
solvent, blow dry. Blow out lines.
If pump oil consumption is excessive, replace oil metering collar
and pin in pump.

16-26. TROUBLE SHOOTING -- GYROS.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

HORIZON BAR FAILS TO RESPOND.
Central or instrument
filter dirty.

Check filter.

Clean or replace filter.

Adjust or replace relief valve.

Suction relief valve improperly adjusted.
Faulty suction gage.

Substitute known-good suction
gage and check gyro response.

Replace suction gage.

Vacuum pump or venturi
failure.

Check pump or venturi.

Replace pump or venturi.

Vacuum line kinked or
leaking.

Check lines for damage and
leaks,

Repair or replace damaged lines,
tighten connections.

Substitute known-good gyro and
check indication.

Replace instrument.

HORIZON BAR DOES NOT SETTLE.
Defective mechanism.
Insufficient vacuum.
Excessive vibration.

Adjust or replace relief valve.
Check panel shock mounts.

Replace defective shock mounts.

HORIZON BAR OSCILLATES OR VIBRATES EXCESSIVELY.
Central or instrument
filter dirty.

Check filter.

Suction relief valve improperly adjusted.

Clean or replace filter.
Adjust or replace relief valve.

Faulty suction gage.

Substitute known-good suction
gage and check gyro indication.

Replace suction gage.

Defective mechanism.

Substitute known-good gyro and
check indication.

Replace instrument.

Excessive vibration.

Check panel shock mounts.

Replace defective shock mounts.

EXCESSIVE DRIFT IN EITHER DIRECTION.
Central or instrument
air filter dirty.

Check filter.

Low vacuum, relief valve improperly adjusted.

Clean or replace filter.
Adjust or replace relief valve.

Faulty suction gage.

Substitute known-good suction
gage and check gyro indication.

Replace suction gage.

Vacuum pump or venturi
failure.

Check pump or venturi.

Replace pump or venturi.

Vacuum line kinked or
leaking.

Check lines for damage and
leaks.

Repair or replace damaged lines,
tighten connections.

16-17

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

DIAL SPINS IN ONE DIRECTION CONTINUOUSLY.
Operating limits have been
exceeded.
Defective mechanism.

Cage and reset when airplane
is level.
Substitute known-good gyro
and check indication.

Replace instrument.

16-27. TROUBLE SHOOTING -- VACUUM PUMP.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

EXCESSIVE OIL IN DISCHARGE.
Excessive flow to pump.

Check pump vent plugs.

Clean vent plugs.

Clogged oil separator.

Check separator for obstructions.

Clean separator.

Damaged engine drive seal.

Replace gasket.

HIGH SUCTION.
Suction relief valve
screen clogged.

Check screen for obstructions.

Clean or replace screen.

LOW SUCTION.
Relief valve leaking.
Vacuum pump failure.

Replace relief valve.
Substitute known-good pump
and check pump suction.

Replace vacuum pump.

LOW PRESSURE.
Safety valve leaking.
Vacuum pump failure.

16-18

Replace safety valve.
Substitute known-good pump
and check pump pressure.

Replace vacuum pump.

16-28.

TROUBLE SHOOTING -- VACUUM SWITCH (TYPE 34B GYRO HORIZON).
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

FALSE INDICATION FROM "HI" AND "LO" VACUUM INDICATOR LIGHTS.
Leakage of pressure through
switch connection.

Check connection for security.

Tighten loose connection.

Leaking switch diaphragm.

Replace switch.

Bent or loose contacts.

Replace switch.

INDICATOR LIGHT FAILURE.
Diaphragm does not return to
normal position.
Loose electrical connections.

Replace switch.
Check all connections for
security.

Tighten all connections.

Worn or corroded switch
contact points.
Bulb burned out.

Replace switch.
Test lights with vacuum lights
test switch.

16-29. VACUUM SYSTEM REMOVAL. The various
components of the vacuum system are secured by
conventional clamps, mounting screws and nuts. To
remove a component, remove the mounting screws
and disconnect the inlet and discharge lines.
16-30. VACUUM SYSTEM REPLACEMENT. When
replacing a vacuum system component, make sure
connections are made correctly. Use thread lubricant
sparingly and only on male threads. Avoid overtightening connections. Before reinstalling a vacuum
pump, probe the oil passages in the pump and engine,
to make sure they are open. Place the mounting pad
gasket in position over the studs and make sure it does
not block the oil passages. Coat the pump drive
splines lightly with a high-temperature grease such
as Dow Silicone #30 (Dow-Corning Co., Midland,
Mich.). After installing the pump, before connecting the plumbing, start the engine and hold a piece
of paper over the pump discharge to check for proper
lubrication. Proper oil low through the pump is
one to four fluid ounces per hour.

Install new bulb.

Never apply compressed air to lines or components installed in the airplane. The excessive pressures will damage the gyro instruments. If an obstructed line is to be blown
out, disconnect it at both ends and blow from
the instrument panel out.
16-32. SUCTION GAGE READINGS. On aircraft
equipped with an engine-driven vacuum pump, a
suction gage reading of 5.3 inches of mercury is desirable for gyro instruments. However, a range of
4.6 to 5.4 inches of mercury is acceptable. The
standard Model 172 uses a single venturi to provide
suction, and may be equipped with a relief valve.
On venturi systems the suction gage should indicate
between 3. 5 and 5.4 inches of mercury at cruising
speeds. On systems with a vacuum pump, relief
valve, and with or without a central filter, adjust
relief valve (with engine operating at 1900 rpm) to
obtain 5. 3. 1 inches of mercury. If no suction gage
is used, adjust the relief valve until the "LO VAC"

16-31. VACUUM SYSTEM CLEANING. In general,
low-pressure, dry compressed air should be used
in cleaning vacuum system components removed
from the airplane.

required to light goes out count the number of turns
required to
adjust
the "HI VAC" indicator light
illuminate, then adjust the relief valve back one
half the number of turns noted. The indicator lights
warn of high or low vacuum when illuminated; both

Components such as the oil separator and suction
relief valve which are exposed to engine oil and
dirt should be washed with Stoddard solvent, then
dried with a low-pressure air blast. Check hoses
for collapsed inner liners as well as external damage.

are out when vacuum is within permissible limits
NOTE
On aircraft equipped with a central air filter
(1965 and on), remove filter element and
make adjustments. Be sure filter element
is clean before installing. If reading drops
noticeably, install new filter element. An
accessory kit is available to equip earlier
models with a central filter.
16-19

NOTE9

When pictorial gyros are installed, vacuum switch (12)

and push-button switch (13)
replace suction gage.

6w
2

150D

150C

Y-.

>
''
-*'>?

\"-"-'i'

(

'' s,

150C

Hose Assembly
Nipple

V1.

-2..--

)

150D
20

Relief Valve

Fitting

Hose Assembly

Hose

9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.

Suction Gage
Horizontal Gyro
Directional Gyro
Vacuum Switch
Switch
Tee
Elbow
Hose
Vent Line
Line (To Engine)
Vacuum Pump
Oil Separator

150C

Figure 16-5.
16-20

Model 150 Engine-Driven Vacuum Systems (Sheet 1 of 2)

1965 THRU MID-1966

MID-1966 THRU 1967

1968 AND ON

/13

NOTE
Any one of three different
combinations of gyros may
be installed during 1968.
Each gyro has outlet markings
depicting hose routing.

14
Figure 16-5.

1.
2.
3.

Section Hose
Firewall
Relief Valve

9.
10.
11.

Gyro Horizon
Directional Gyro
Filter Assembly

Suction Hose

12.

Oil Separator

5.
6.
7.
8.

Wing Nut
Filter Element
Filter Bracket
Suction Gage

13.
14.
15.
16.

Vent Line
Oil Drain Hose
Exhaust Hose
Vacuum Pump

Model 150 Engine Driven Vacuum Systems (Sheet 2 of 2)
16-21

NOTE
2
This is a typical venturi installation for Model 172
aircraft, except for the Skyhawk and P172 which
have vacuum pump provisions.
A relief valve is not standard on Models prior to
172E, but may be installed if desired.
2

1-72D-

172E

Jv^/.. !\MID-1966 THRU 1965 TO MID-1966

16-22

/"~y

''"-J
17 2E
~
/

z~g/{4
4.

Hose

10.

Fuselage Skin

7.
7.
8.
9.
10.
11.
12.

Filter Bracket
Bracket
Filter
Filter Element
Element

172D

172F THRU 172H-

MID-1966 THRU 197

· ^- \ '^'^^'s^
-^^L

/'^.^^'^^

}

1.
1.
^2.
2.
3.
3.
4.
5.
6.

Suction Gage
Gage
Suction
Gyro
Horizon
Gyro Horizon
Gyro
Directional Gyro
Hose
Hose
Hose

Figure 16-6. Venturi-Driven Vacuum System
16-22

Wing Nut
Wing
Nut
Fuselage Skin
Venturi
Relief Valve

172E
NOTE
pictorial gyros are
Installed, vacuum switch
(7) and push-button switch
(8) replace suction gage.

"When

1.
2.
3.
4.
5.

Hose
Clamp
Nipple
Vacuum Pump
Drain Line

Suction Gae

7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.

Vacuum Switch
Push-button Switch
Directional Gyro
Gyro Horizon
Hose
Bracket
Filter Element
Wing Nut
Clamp
Relief Valve
Oil Separator

Skyhawk

7.
.s

\. ;/
\~/

172D

_-.

A
1
7
7

\
g

,172F

2
P172

Figure 16-7.

Models 172 Skyhawk and P172 Engine-Driven Vacuum Systems
16-23

.::

:;.--

:.....-

MID-1966 THRU 1967
I
............

*7.

.. ....'. " ./.. .
'".:'.
MODEL 172I

Figure 16-7A. Model 172 Skyhawk Engine-Driven Vacuum System
16-24

......

180F and 185B

%9F1

.1
12

182 Series Prior to 182H

180G
5/
-Ci'$1*17

i,8'

180

180F, 185B and
182 Series Prior to 182H

85C

7
^^fi

1^ \

^ A

,^^^
9

185C and 180G

NOTE
When pictorial gyros are installed,
vacuum switch (15) and test switch
(16) replace suction gage.

Figure 16-8.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

Bracket

11.

Hose

Oil Separator
Hose (To Engine)
Vacuum Pump
Discharge Hose
Hose
Tube
Suction Gage
Gyro Horizon
Directional Gyro

12.
13.
14.
15.
16.
17.
18.
19.

Line
Tee
Hose Assembly
Vacuum Switch
Test Switch
Hose
Clamp
Relief Valve

Models 180, 182, and 185 Engine-Driven Vacuum Systems (Sheet 1 of 3)
16-25

MODEL 182 - 1965 THRU 1966

%*3

MODEL-180 AND
185 -1965 THRU 1966

|MDE

182 -- 1967...
"'

MODEL 182 - 1967

/ ' /

/
13

Figure 16-8.
16-26

-MODEL
~~~/^~~/.^^<~~~

/
12

€

180 AND 185 - 1967

9!^ 1.
2.
3.
4.
5.
6.
7.

SuctionGage
Gyro Horizon
Directional Gyro
Suction Hose
Filter Bracket
Filter Element
Wing Nut

8.
9.
10.
11.
12.
13.
14.
15.

Flrewall
Relief Valve
Suction Hose
Oil Drain Hose
Vacuum Pump
Exhaust Hose
Oil Separator
Vent Line

Models 180, 182, and 185 Engine-Driven Vacuum Systems (Sheet 2 of 3)

TO RELIEF VALVE

MODEL 182 - 1968 AND ON
AND ALL SERIVCE PARTS

MODELS 180, 185 AND A1851968 AND ON AND ALL SERVICE PARTS

1.
2.
2.
3.
5.
6.
6.

Suction Gage
Directional Gyro
Directional
Gyro
Gyro Horizon
ent
Filter B
Elemnt
Fihter
Wing Nut

NOTE
Any one of three different combinations
of gyros may be installed during 1968.
Each gyro has outlet markings depicting

hose routing.
Refer to Sheet 2 for equipment located
forward of the firewall.

Figure 16-8.

Models 180, 182, and 185 Engine-Driven Vacuum Systems (Sheet 3 of 3)
16-26A

16-33. ENGINE INDICATORS
16-34. TACHOMETER.
The tachometer used on Cessna single-engine aircraft are mechanical indicators driven at half of the
crankshaft speed by flexible shafts. Most tachometer difficulties will be found in the drive shaft. To
function properly, the shaft housing must be free of kinks, dents, and sharp bends. There should be
no bend on a radius shorter than six inches, and no bends within three inches of either terminal. If a
tachometer is noisy or the pointer oscillates, check the cable housing for kinks, sharp bends and
damage. Disconnect the cable at the tachometer and pull it out of the housing. Check the cable for
worn spots, breaks and kinks.
NOTE: On 551-series tachometers (identified by vendor number on the back of the case), do not
remove the drive support. This support appears to be a dust cover, but is essential to proper
operation.
Before replacing a tachometer cable in the housing, coat the lower two thirds with AC Type ST-640
Speedometer cable grease or Lubriplate No. 110. Insert the cable in the housing as far as possible,
then slowly rotate it to make sure it is seated in the engine fitting. Insert the cable in the tachometer,
making sure it is seated in the drive shaft, then reconnect the housing and torque to 50 poundinches (at the instrument).
16-35

MANIFOLD PRESSURE GAGE
The manifold pressure gage is a barometric instrument which indicates the absolute pressure in the
intake manifold in inches of mercury; thus with the engine stopped or at sudden full throttle and
maximum RPM, it will register approximately the ambient barometric pressure. The Model A185
(1966 and On) has the manifold pressure and fuel flow gages in one instrument case. However,
each instrument operates independently.

16-36 TROUBLESHOOTING - MANIFOLD PRESSURE GAGE
PROBABLE CAUSE
ISOLATION PROCEDURE

REMEDY

EXCESSIVE ERROR AT EXISTING BAROMETRIC PRESSURE.
Pointer shifted.
Leak in vacuum bellows.
Loose pointer
Leak in the pressure line.
Test the line and connections for
leaks
Condensate or fuel in the line.
Check the lines for obstructions.

Replace instrument.
Replace instrument.
Replace instrument.
Repair or replace damaged
lines, tighten connection.
Blow out the line.

JERKY MOVEMENT OF THE POINTER.
Excessive internal friction.
Rocker shaft screws tight.
Link springs too tight.
Dirty pivot bearings.
Defective mechanism.
Leak in pressure line.
Test the lines and connections for
leaks.

Replace the instrument.
Replace the instrument.
Replace the instrument.
Replace the instrument.
Replace the instrument.
Repair or replace the damaged
line, tighten connections.

SLUGGISH OPERATION OF THE POINTER
Foreign matter in the line.
Check the line for obstructions.
Damping needle dirty
Leak in the pressure line.
Test the line and connection for leaks.

Revision 1
© Cessna Aircraft Company

Blow out the lines.
Replace the instrument
Repair or replace the damaged
line, tighten the connections.
16-27
Aug 4/2003

16-36 TROUBLESHOOTING - MANIFOLD PRESSURE GAGE (Cont.).
PROBABLE CAUSE
ISOLATION PROCEDURE
EXCESSIVE POINTER VIBRATION.
Tight rocker pivot bearings.
Excessive panel vibration.
Check panel shock mounts.

IMPROPER CALIBRATION.
Faulty mechanism.
NO POINTER MOVEMENT.
Faulty mechanism.
Broken pressure line.

REMEDY

Replace instrument.
Replace defective shock
mounts.

Replace instrument.

Check line and connections for
breaks.

Replace instrument.
Repair or replace damaged line.

16-37. CYLINDER HEAD TEMPERATURE GAGES.
Two types of cylinder head temperature gages are used in the various models, the thermocouplepowered type and the electrical-powered bulb type gage. Spark plug gasket thermocouples provide
power to the thermocouple-type gages; cylinder head temperature bulbs regulate power to electrical
system powered gages. On thermocouple type installations, the length of the thermocouple leads is
important; shortening or lengthening the wires will alter circuit resistance and cause erroneous gage
indication. The Rochester and Stewart Warner gages are connected the same way, but the Rochester
gage does not have a calibration pot and cannot be adjusted. Refer to Table 1 on page 16-34A when
troubleshooting the cylinder head temperature gage.

SHOP NOTES:

16-28

Revision 1
Aug 4/2003

16-38 TROUBLESHOOTING - CYLINDER HEAD TEMEPERATURE GAGE
PROBABLE CAUSE
GAGE INOPERATIVE.
No current to the circuit (bulb type).
Defective gage, thermocouple, bulb
or circuit.

ISOLATION PROCEDURE
Check circuit breaker, electrical
circuit to gages.
Isolate with ohmmeter check of
circuits.

GAGE READS HIGH (THERMOCOUPLE TYPE CIRCUIT).
Shortened thermocouple lead.
Check with ohmmeter. Total
(Resistance too low).
resistance through lead and
thermocouple should be 2 ohms.
GAGE READS LOW (THERMOCOUPLE TYPE CIRCUIT).
Too long a lead, or defective lead or Check resistance as above.
thermocouple.
GAGE FLUCTUATES RAPIDLY (BULB-TYPE CIRCUIT).
Loose or broken wire permitting
Inspect the circuit wiring.
alternate make and brake of gage
current.
GAGE READS TOO HIGH ON SCALE (BULB TYPE CIRCUIT).
High voltage.
Gage off calibration.
GAGE READS TOO LOW ON SCALE (BULB-TYPE CIRCUIT).
Low voltage.

REMEDY
Repair electrical circuit.
Repair or replace defective
item.
Replace defective parts with
Cessna lead.

Replace defective parts with
Cessna parts.
Repair or replace defective
wire.

Check "A" terminal.
Replace the instrument.

Gage off calibration.

Check the voltage supply and
"D" terminal.
Replace the instrument.

GAGE READS OFF SCALE AT HIGH END (BULB-TYPE CIRCUIT).
Break in bulb.
Break in bulb leads.
Internal break in the gage.

Replace the instrument.
Replace the instrument.
Replace the instrument.

OBVIOUSLY INCORRECT READING (BULB-TYPE CIRCUIT).
Defective gage mechanism.
Incorrect calibration.

Replace the instrument.
Replace the instrument.

Revision 1
© Cessna Aircraft Company

16-29
Aug 4/2003

16-39. CYLINDER HEAD TEMPERATURE GAGE MAINTENANCE.
The cylinder head temperature gage and thermocouple or bulb require no maintenance other than
cleaning, making sure the lead is properly supported, and all connections are clean, tight, and properly
insulated. To make sure the resistance in the thermocouple circuit matches the instrument calibration,
always replace the gage, thermocouple, and lead with genuine Cessna parts of the correct number. The
Rochester and Stewart Warner gages are connected the same, but the Rochester gage does not have a
calibration pot and cannot be adjusted. Refer to Table 1 on page 16-34A when troubleshooting the
cylinder head temperature gage.
16-40. OIL PRESSURE GAGE.
On some airplanes, a Bourdon tube-type oil pressure gage is installed. This is a direct-reading
instrument, operated by a pressure pickup line connected to the engine main oil gallery. The oil pressure
line from the instrument to the engine should be filled with kerosene, especially during cold weather
operation, to obtain immediate oil indication. Electrically actuated gages are installed on some airplanes
which utilize a pressure sending bulb.
16-41. TROUBLESHOOTING - OIL PRESSURE GAGE (DIRECT-READING).
PROBABLE CAUSE
GAGE DOES NOT
REGISTER.
Pressure line clogged.
Presure line broken.
Fractured Bourdon tube.
Gage pointer loose on staff.
Damaged gage movement.

ISOLATION PROCEDURE

Check line for obstructions.
Check line for leaks and damage.

GAGE POINTER FAILS TO RETURN TO ZERO.
Foreign matter in line.
Check line for obstructions.
Foreign matter in Bourdon
tube.
Bourdon tube stretched.
GAGE DOES NOT REGISTER PROPERLY.
Faulty mechanism.
GAGE HAS ERRATIC OPERATION.
Worn or bent movement.
Foreign matter in Bourdon
tube.
Dirty or corroded movement.
Pointer bent and rubbing on
dial, dial screw, or glass
Leak in pressure line.
Check line for leaks and damage.

16-30
© Cessna Aircraft Company

REMEDY

Clean line.
Repair or replace damaged line.
Replace instrument.
Replace instrument.
Replace instrument.

Clean line.
Replace instrument.
Replace instrument.

Replace instrument.

Replace instrument.
Replace instrument.
Replace instrument.
Replace instrument.
Repair or replace damaged line.

Revision 1
Aug 4/2003

16-42. DELETED.
16-43. DELETED.
16-44. OIL TEMPERATURE GAGE.
On some airplanes, the oil temperature gage is a Bourdon tube type pressure instrument connected by
armored capillary tubing to a temperature bulb in the engine. The temperature bulb, capillary tube, and
gage are filled with fluid and sealed. Expansion and contraction of fluid in the bulb with temperature
changes operates the gage. Checking capillary tube for damage and fittings for security is the only
maintenance required. Since the tube's inside diameter is small, small dents and kinks, which would be
acceptable in larger tubing, may partially or completely close off the capillary, making the gage
inoperative. Some airplanes are equipped with gages that are electrically actuated and are not adjustable.
Refer to Table 2 on page 16-34B when troubleshooting the oil temperature gage.
NOTE: On some Model 172 airplanes, an O-ring has been added on the oil temperature bulb at the
engine to provide a better seal for the bulb. This O-ring should be installed on all models with a
Bourdon type gage.
16-45. CARBURETOR AIR TEMPERATURE GAGES.
The electric carburetor air temperature gage is of the resistance-bridge type, in which changes in the
electrical resistance of the element in the sensing bulb, which occur with temperature changes, are
indicated by a meter, its dial calibrated for temperature. The resistance system requires current from the
electrical system (aircraft's bus) and operates only when the master switch is on. Although both the
instrument and the sensing bulb are grounded, two leads are used between them to avoid the possibility
of instrument error intruduced by poor electrical bonds in the airframe.

SHOP NOTES:

Revision 1
© Cessna Aircraft Company

16-31
Aug 4/2003

16-46 CARBURETOR AIR TEMPERATURE GAUGE (ELECTRIC)
PROBABLE CAUSE

ISOLATION PROCEDURE

GAGE POINTER STAYS OFF LOW END OF SCALE.
Blown fuse/circuit breaker out. Check fuse/circuit breker.

Master switch OFF or switch
defective.
Broken or grounded leads
between gage and sensing
unit.
Defective gage or sensing
unit.

REMEDY

Replace fuse/reset circuit breaker.

Check the switch ON.

Replace defective switch.

Check circuit wiring.

Repair or replace defective wiring

Substitute a known good gage or
sensing unit.

Replace gage or sensing unit.

GAGE POINTER GOES OFF HIGH END OF SCALE.
Check circuit wiring.
Broken or grounded lead.
Substitute a known good gage or
Defective gage or sensing
sensing unit.
unit.

Repair or replace defective wiring.
Replace gage or sensing unit.

GAGE OPERATES INTERMITTENTLY.
Check circuit wiring.
Defective Master switch,
broken or grounded lead.
Substitute a known good gage or
Defective gage or sensing
sensing unit.
unit.

Replace switch, repair or replace
defective wiring.
Replace gage or sensing unit.

EXCESSIVE POINTER OSCILLATION.
Check circuit wiring.
Loose or broken lead.
Substitute a known good gage or
Defective gage or sensing
sensing unit.
unit.
Check panel shock mounts.
Excessive panel vibration.
OBVIOUSLY INCORRECT TEMPERATURE READING
Substitute a known good gage or
Defective gage or sensing
sensing unit.
unit.
POINTER FAILS TO GO OFF THE SCALE WITH THE CURRENT
OFF.
Defective Master switch.
Substitute a known good gage.
Defective gage.

16-32
© Cessna Aircraft Company

Repair or replace defective wiring.
Replace gage or sensing unit.
Replace defective shock mounts.

Replace gage or sensing unit.

Replace switch.
Replace gage.

Revision 1
Aug 4/2003

16-47.FUEL QUANTITY INDICATORS.
The electric fuel quantity indicators are the magnetic type. In the magnetic type indicator, fuel level
indication is instantaneous. The fuel quantity indicators are used in conjunction with a float-operated
variable-resistance transmitter in each fuel tank. The tank-full position of the transmitter float produces a
minimum resistance through the transmitter, permitting maximum current flow through fuel quantity
indicator and maximum pointer deflection. As the fuel level of the tank is lowered, resistance in the
transmitter is increased, producing a decreased current flow through the fuel quantity indicator and a
smaller pointer deflection.
16-48. TROUBLESHOOTING - FUEL QUANTITY INDICATORS (ELECTRIC).
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

FAILURE TO INDICATE.
No power to indicator or transmitter.
(Pointer stays below E.)

Check fuse/circuit breaker, inspect
for open circuit.

Replace fuse/reset breaker,
repair or replace defective
wire.

Grounded wire.
(Pointer stays above E.)
Low voltage.

Check for partial ground between
transmitter and gage.
Check voltage at indicator.

Repair or replace defective
wire.

Defective indicator.

Substitute known-good indicator;
also see paragraph 13-3.

Replace indicator.

Substitute known-good indicator;
also see paragraph 13-3.
Substitute known-good transmitter;
also see paragraph 13-3.

Replace indicator.

Check voltage at indicator.

Correct voltage.

OFF CALIBRATION.
Defective indicator.
Defective transmitter.
Low or high voltage.

Correct voltage.

Recalibrate or replace.

STICKY OR SLUGGISH INDICATOR OPERATION.
Defective indicator.
Low voltage.
ERRATIC READINGS.
Loose or broken wiring on indicator
or transmitter.
Defective indicator or transmitter.

Substitute known-good indicator;
also see paragraph 13-3.
Check voltage at indicator.

Replace indicator.

Inspect circuit wiring.

Repair or replace defective
wire.

Substitute known-good component;
also see paragraph 13-3.

Replace indicator or
transmitter.

Correct voltage.

Replace switch.

Defective master switch.

Revision 1
© Cessna Aircraft Company

16-33
Aug 4/2003

16-49.

TRANSMITTER ADJUSTMENT.
WARNING:

16-49A.

USING THE FOLLOWING FUEL TRANSMITTER CALIBRATION PROCEDURES ON
COMPONENTS OTHER THAN THE ORIGINALLY INSTALLED (STEWART WARNER)
COMPONENTS WILL RESULT IN A FAULTY FUEL QUANTITY READING.

STEWART WARNER GAGE TRANSMITTER CALIBRATION.
Chances of transmitter calibration changing in normal service is remote; however it is possible that the
float arm or the float arm stops may become bent if the transmitter is removed from the fuel cell/tank.
Transmitter calibration is obtained by adjusting float travel. Float travel is limited by the float arm stops.
WARNING:

USE EXTREME CAUTION WHILE WORKING WITH ELECTRICAL COMPONENTS OF
THE FUEL SYSTEM. THE POSSIBILITY OF ELECTRICAL SPARKS AROUND AN
"EMPTY" FUEL CELL CREATES A HAZARDOUS SITUATION.

Before installing transmitter, attach electrical wires and place the master switch in the "ON" position.
Allow float arm to rest against lower float arm stop and read indicator. The pointer should be on E
(empty) position. Adjust the float arm against the lower stop so pointer indicator is on E. Raise float
until arm is against upper stop and adjust upper stop to permit indicator pointer to be on F (full). Install
transmitter in accordance with paragraph 13-17.
16-49B.

ROCHESTER FUEL GAGE TRANSMITTER.
Do not attempt to adjust float arm or stop. No adjustment is allowed.

16-49C.

FUEL QUANTITY INDICATING SYSTEM OPERATIONAL TEST.
WARNING:

REMOVE ALL IGNITION SOURCES FROM THE AIRPLANE AND VAPOR HAZARD
AREA. SOME TYPICAL EXAMPLES OF IGNITION SOURCES ARE STATIC
ELECTRICITY, ELECTRICALLY POWERED EQUIPMENT (TOOLS OR ELECTRONIC
TEST EQUIPMENT - BOTH INSTALLED ON THE AIRPLANE AND GROUND
SUPPORT EQUIPMENT), SMOKING AND SPARKS FROM METAL TOOLS.

WARNING:

OBSERVE ALL STANDARD FUEL SYSTEM FIRE AND SAFETY PRACTICES.

1. Disconnect all electrical power from the airplane. Attach maintenance warning tags to the battery
connector and external power receptacle stating:
WARNING:

DO NOT CONNECT ELECTRICAL POWER, MAINTENANCE IN PROGRESS.

2. Electrically ground the airplane.
3. Level the airplane and drain all fuel from wing fuel tanks.
4.

Gain access to each fuel transmitter float arm and actuate the arm through the transmitter's full
range of travel.
A. Ensure the transmitter float arm moves freely and consistently through this range of travel.
Replace any transmitter that does not move freely or consistently.
WARNING:

USE EXTREME CAUTION WHILE WORKING WITH ELECTRICAL
COMPONENTS OF THE FUEL SYSTEM. THE POSSIBILITY OF
ELECTRICAL SPARKS AROUND AN "EMPTY" FUEL CELL CREATES A
HAZARDOUS SITUATION.

16-34
© Cessna Aircraft Company

Revision 1
Aug 4/2003

B. While the transmitter float arm is being actuated, apply airplane battery electrical power as required
to ensure that the fuel quantity indicator follows the movement of the transmitter float arm. If this
does not occur, troubleshoot, repair and/or replace components as required until the results are
achieved as stated.
NOTE: Stewart Warner fuel quantity indicating systems can be adjusted. Refer to this section for
instructions for adjusting Stewart Warner fuel indicating systems.
Rochester fuel quantity indicating system components are not adjustable, only component
replacement or standard electrical wiring system maintenance practices are permitted.
5.

With the fuel selector valve in the "OFF" position, add unusable fuel to each fuel tank.

6. Apply electrical power as required to verify the fuel quantity indicator indicates "EMPTY".
A.

If "EMPTY" is not indicated, adjust, troubleshoot, repair and/or replace fuel indicating
components as required until the "EMPTY" indication is achieved.
NOTE:

Fill tanks to capacity, apply electrical power as required and verify that the fuel quantity indicators
indicate "FULL".
A.

If "FULL" is not indicated, adjust, troubleshoot, repair and/or replace fuel indicating
components as required until the "FULL" indication is achieved.
NOTE:

8.
16-49D.

Stewart Warner fuel quantity indicating systems can be adjusted. Refer to this
section for instructions for adjusting Stewart Warner fuel indicating systems.
Rochester fuel quantity indicating system components are not adjustable, only
component replacement or standard electrical wiring system maintenance
practices are permitted.

Install any items and/or equipment removed to accomplish this procedure, remove maintenance
warning tags and connect the airplane battery.

Cylinder Head Temperature Indicating System Resistance Table 1.
The following table is provided to assist in the troubleshooting the cylinder head temperature indicating
system components.
Select the cylinder head temperature sending unit part number that is used in your airplane from the left
column and the temperature from the column headings. Read the ohms value under the appropriate
temperature column.
Part Number
S1372-1
S1372-2
S1372-3
S1372-4
S2334-3
S2334-4

Type
CHT
CHT
CHT
CHT
CHT
CHT

200°F

220°F
310.0
310.0

745.0
745.0

Revision 1
© Cessna Aircraft Company

450°F
34.8
34.8
113.0
113.0

475°F
46.4

38.0
38.0

16-34A
Aug 4/2003

16-49E. Oil Temperature Indicating System Resistance Table 2.
The following table is provided to assist in troubleshooting the oil temperature indicating system
components.
Select the oil temperature sending unit part number that is used in your airplane from the left
column and the temperature from the column headings. Read the ohms value under the
appropriate temperature column.
Part Number
S1630-1
S1630-3
S1630-4
S1630-5
S2335-1

Type
Oil Temp
Oil Temp
Oil Temp
Oil Temp
Oil Temp

72°F

120°F

165°F

220°F
46.4

250°F
52.4
52.4

620.0
620.0
192.0
990.0

34.0

Revision 1

16-34B
© Cessna Aircraft Company

Aug 4/2003

16-50. FUEL FLOW INDICATOR.
A fuel flow indicator is used with the Continental fuel injection system on Model 185 aircraft. The indicator
is a fuel pressure gage calibrated to indicate the approximate gallons per hour of fuel being metered to
the engine. It is operated by a pressure line from the fuel distributor manifold on the engine. The model
A185 (1966 and on) has the manifold pressure and fuel flow gages in one instrument case. However,
each instrument operates independently.
16-51. TROUBLE SHOOTING - FUEL FLOW INDICATOR.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

DOES NOT REGISTER.
Pressure line clogged.

Check line for obstructions.

Blow out line.

Pressure line broken.

Check line for leaks and damage.

Repair or replace damaged
line.

Fractured bellows or damaged
mechanism.

Replace instrument.

Clogged snubber orifice.
Pointer loose on staff.

Replace instrument.
Replace instrument.

POINTER FAILS TO RETURN TO ZERO.
Foreign matter in line.
Check line for obstructions.
Clogged snubber orifice.
Damaged bellows or mechanism.

Blow out line.
Replace instrument.

INCORRECT OR ERRATIC READING
Damaged or dirty mechanism.
Pointer bent, rubbing on dial or
glass.

Replace instrument.
Replace instrument.

Leak or partial obstruction in
pressure line.

Check line for obstructions or leaks.

Revision 1
© Cessna Aircraft Company

Replace instrument.

Blow out dirty line, repair or
tighten loose connections.

16-34C
Aug 4/2003

16-52. MAGNETIC COMPASS.
The magnetic compasses used in Cessna single-engine airplanes are liquid-filled, with expansion
provisions to compensate for temperature changes. They are equipped with compensating magnets
adjustable from the front of the case.
The compasses are individually-lighted by GE No. 330 lamps inside the compass case, controlled by the
instrument light's rheostat switch. No maintenance is required on the compass except an occasional
check on a compass rose with adjustment of the compensation, if necessary, and replacement of the
lamp.
NOTE: Both 3-volt and 12-volt lamps have been used with the compass lights. Check the voltage on the
old lamp before installing a replacement.
On the Model 182H and on, the compass mount is attached by three screws to a base plate. The base
plate is bonded to the windshield with Methylene Chloride. A tube containing the compass light wires is
attached to the metal strip at the top of the windshield. Removal of the compass is accomplished by
removing the screw at the forward end of the compass mount, unfastening the metal strip at the top of the
windshield, and cutting the two wire splices. Removal of the compass mount is accomplished by
removing the three screws attaching the mount to the base plate. Access to the inner screw is gained
through a hole in the bottom of the mount, through which a thin screwdriver can be inserted. When
installing the compass, it will be necessary to re-splice the compass light wires.
During the 1967 model-year and on, a small permanent magnet is installed on the underside of the cowl
deck forward of the compass, on Model 150 Series airplanes (prior to 1968). Installation of this magnet
aids in compensating the compass, but it must be installed with its north-seeking pole up (against the
underside of the cowl deck) and it must be rotated to the left 45°. Installation is shown in Figure 16-19A.

16-34D
Cessna Aircraft Company

Revision 1
Aug 4/2003

B1685

9
1. Windshield
2. Base Plate
3. Insert
4. Tube
5. Nut
6. Compass Light
7. Screw

8. Compass Card
9. Compass
10. Compass Mount
11. Metal Strip
12. Electrical Wire
13. Washer
14. Lockwasher

11
4

Figure 16-9. Compass Installation - Models 182H and On, and 150H and On

Revision 1
© Cessna Aircraft Company

16-35
Aug 4/2003

VIEW A-A

NOTE
An easy method of determining which ti
the north-seeking pole of the magnet is
to hold it with one of its flat sides (through
which the hole is drilled next to the lubber line. If the compass reads north, the
north-seeking side of the magnet is adjacent to the compass. If the compass
reads south, the south-seeking side of
the magnet is adjacent to the compass.

Figure 16-19A. Compass Compensating Magnet Installation - Model 150 (Prior to 1968)

16-36
© Cessna Aircraft Company

Revision 1
Aug 4/2003

16-53. STALL WARNING HORN AND TRANSMITTER.
(See paragraph 17-29. )
16-53A. PNEUMATIC STALL WARNING HORN.
(See figure 16-10. ) The system is composed of an
adjustable plate on the left wing leading edge that is
connected to a reed type horn by means of plastic
tubing. The horn is actuated approximately 5 to 10
miles per hour above stalling speed as a negative
air pressure area at the wing leading edge causes
a reverse flow of air through the horn. By moving
adjustable plate (7) up, actuation of the horn will

occur at a higher speed, and moving the plate down
causes actuation to occur at a slower speed. Center
the adjustable plate opening in the wing leading edge
opening upon installation, then flight test aircraft,
observing horn actuation during stall. Readjust
plate to obtain desired results if necessary. Approximately 3/32 inch adjustment of the plate will
change speed at which horn actuation occurs by 5
miles per hour. To test horn operation, cover
opening in plate (7) with a clean cloth, such as a
handkerchief, and apply a slight suction by mouth
to draw air through the horn.

Doorpost Cover

2.
3.

Horn
Reed

4.
5.

Adapter
Scoop

6.
7.

Felt Seal
Adjustable Plate

NOTE

MODEL 150 - 1966 AND ON
MODEL 172 - 1967 AND ON
MODELS 180 AND 185 - EARLY 1967 AND ON

Use No. 579.6 Presstite sealer between adjustable plate (7) and wing leading edge to ensure
positive seal. This seal is essential to proper
stall warning horn actuation. Adapter (4) and
scoop (5) are bonded together. They should be
replaced as an assembly.

Figure 16-10.

Pneumatic Stall Warning System
16-37

16-54. TURN-AND-BANK INDICATOR. The turnand-bank indicator used on Cessna single-engine aircraft is an electrically operated instrument. It is

16-55.

powered by the aircraft electrical system, and therefore, operates only when the master switch is on.
Its electrical circuit is protected by an automaticallyresetting circuit breaker.

TROUBLE SHOOTING -- TURN-AND-BANK INDICATOR.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

INDICATOR POINTER FAILS TO RESPOND.
Automatic resetting circuit
breaker defective.

Check circuit breaker.

Replace circuit breaker.

Master-switch-"OF-' or
switch defective.

Check switch "ON."

Replace defective switch.

Broken or grounded lead to
indicator,

Check circuit wiring.

Repair or replace defective
wiring.

Indicator not grounded.

Check ground wire.

Repair or replace defective wire.
Replace instrument.

Defective mechanism.
HAND SLUGGISH IN RETURNING TO ZERO.

Replace instrument.

Defective mechanism.
Low voltage.

Check voltage at indicator.

Correct voltage.

POINTER DOES NOT INDICATE PROPER TURN.
Replace instrument.

Defective mechanism.
HAND DOES NOT SIT ON ZERO.
Gimbal and rotor out of balance.

Replace instrument.

Hand incorrectly sits on rod.

Replace instrument.

Sensitivity spring adjustment
pulls hand off zero.

Replace instrument.

IN COLD TEMPERATURES, HAND FAILS TO RESPOND OR IS SLUGGISH.
Oil in indicator becomes
too thick.

Replace instrument.

Insufficient bearing end play.

Replace instrument.

Low voltage.

Check voltage at indicator.

Correct voltage.

Check voltage at indicator.

Correct voltage.

NOISY GYRO.
High voltage.
Loose or defective rotor
bearings.

16-38

Replace instrument.

16-55A. TURN COORDINATOR is an electrically operated, gyroscopic, roll-rate turn indicator. Its gyro
simultaneously senses rate of motion roll and yaw
16-55B.

axes which is projected on a single indicator. The
gyro is a non-tumbling type requiring no caging mechanism, and incorporates an a. c. brushless spin motor
with a solid state inverter.

TROUBLE SHOOTING

PROBABLE CAUSE

REMEDY

ISOLATION PROCEDURE

INDICATOR DOES NOT RETURN
TO CENTER.
Friction caused by contamination
in the indicator damping.

Replace instrument.

Friction in gimbal assembly.

Replace instrument.

DOES NOT INDICATE A
STANDARD RATE TURN
(TOO SLOW).
Low voltage.

Measure voltage at instrument.

Correct voltage.
Replace instrument.

Inverter frequency changed.

NOISY MOTOR.
Replace instrument.

Faulty bearings.
ROTOR DOES NOT START.
Faulty electrical connection.

Check continuity and voltage.

Correct voltage or replace
faulty wire.

Inverter malfunctioning.

Replace instrument.

Motor shorted.

Replace instrument.

Bearings frozen.

Replace instrument.

IN COLD TEMPERATURES, HAND FAILS TO RESPOND OR IS SLUGGISH.
Oil in indicator becomes
too thick.

Replace instrument.

Insufficient bearing end play.

Replace instrument.

Low voltage.

Check voltage at instrument.

Correct voltage.

Check voltage to instrument.

Correct voltage.

NOISY GYRO.
High voltage.
Loose or defective rotor
bearings.

Replace instrument.

16-38A

16-56.
ELECTRIC CLOCK. Most 100-series
aircraft are equipped with an electric clock which
operates on 12 volts and requires a one-amp fuse.
The fuse holder is located adjacent to the battery
box. The clock's electrical circuit is separate
from the main electrical system, and will operate
when the master switch is "OFF".
16-56A. HOURMETER. An hourmeter may be installed as optional equipment. The meter operates
electrically, and is actuated by a pressure switch
in the oil system. The meter is powered by the
clock's electrical system, and therefore will operate independent of the master switch. If no clock
is installed, a line direct from the battery contactor
provides the meter with electrical power independent
for operating procedures of sysstem.
16-58. TROUBLE SHOOTING.
PROBABLE CAUSE

of the master switch. A one-amp fuse is located adjacent to the battery box. A small indicator on the
dial face rotates when the meter is actuated. If the
meter is inoperative, and the clock is operating, the
meter or its wiring is faulty and must be replaced.
Beginning in 1967, an additional hourmeter may be installed as optional equipment. It is electrically operated and is actuated by an oil pressure switch as the
engine is started.
16-57.
CESSNA ECONOMY MIXTURE INDICATOR is
an exhaust gas temperature (EGT) sensing device which
is used to aid the pilot in selecting the most desirable
fuel-air mixture for cruising flight at less than 75%
power. Exhaust gas temperature (EGT) varies with
the ratio of fuel-to-air mixture entering the engine
cylinders. See appropriate airplane Owner's Manual

ISOLATION PROCEDURE

REMEDY

GAGE INOPERATIVE.
Defective gage, probe or
circuit.

Isolate with ohmmeter check
of circuit.

Repair or replace defective
part.

See paragraph 16-59.

Check for defective circuit.

Tighten connections, and
repair or replace defective
leads.

INCORRECT READING.
Indicator needs calibrating.

FLUCTUATING READING.
Loose, frayed, or broken
lead, permitting alternate
make and break of current.

16-59. CALIBRATION. Three different types of
indicators have been used. The earliest type (type
"A") was equipped with a calibration adjustment knob
on the face of the instrument and a small calibration
adjustment screw on the back of the case. A later
type (type "B") was equipped with a calibration adjustment knob on the face of the instrument only. The
latest type (type "C") is equipped with a calibration
adjustment potentiometer on the back of the case,
with a reference pointer adjustment screw on the
face of the instrument.
NOTE
The meter reading will change slightly after
initial calibration because of lead deposit
build-up on the probe. These deposits, however, will reach an equilibrium level and

so that a small recalibration will be desirable.
These lead deposits do not in any way affect
the use of the indicator for mixture control or
trouble detection. Leads and/or probes can
be interchanged between types "A" and "B, "
but neither of these can be interchanged with
type "C."
TYPE "A" CALIBRATION:
The calibration adjustment knob located on the face
of the instrument is used to position the pointer over
the reference increment line (4/5 of scale) at peak
EGT with 65% cruise power.
NOTE
This setting will provide relative temperature
within the range of the instrument.
16-39

Rotation of the knob will adjust the pointer three
small divisions up or down ( 75°F). The knob operates a cam and may be rotated either direction
through 360 ° , without damage to the instrument. If
further calibration is required to place the pointer
over the reference line at peak EGT with 65% power,
remove the instrument and use the small calibration
adjustment screw located in the hole at the one o'clock
position on the back of the case. Turning the screw
one complete turn counterclockwise increases the
meter reading one small increment (25°F). Clockwise rotation of the screw decreases the meter reading. Rarely will adjustment of this nature be required after initial installation.
TYPE "B" CALIBRATION:
The calibration adjustment knob located on the face
of the instrument is used to position the pointer over
the reference increment line (4/5 of scale) at peak
EGT with 65% cruise power.

TYPE "C" CALIBRATION:
Since there is no calibration adjustment knob on the
face of the instrument, all calibration is done at the
potentiometer adjustment screw at the back of the
case. Turning the screw clockwise increases the
meter reading, and turning it counterclockwise decreases the meter reading. There is a stop in each
direction and damage can occur if too much torque
is applied against the stops. Approximately 600 F
total adjustment is provided. The adjustable yellow
pointer on the face of the instrument is a reference
pointer only.
16-60. REMOVAL AND INSTALLATION. Removal
of the indicator is accomplished by removing the
mounting screws and disconnecting leads. Tag the
leads to facilitate installation. The thermocouple
probe is secured to the exhaust stack with a clamp.
The clamp should be tightened to 45 pound-inches
and safetied as required.

NOTE

16-61. WING FLAP POSITION INDICATING SYSTEM.

This setting will provide relative temperature
indications for normal cruise power settings
within the range of the instrument.

16-62. The wing flap position transmitter, located in
the right wing, is controlled by mechanical linkge
from the right drive pulley. The transmitter delivers
an electrical signal to the flap position indicator, located in the instrument panel.

Rotation of the knob will adjust the pointer seven
small divisions up or down (±175°F). The knob operates a cam and may be rotated either direction
without damage to the instrument.

NOTE
The Models 150F and on, and 182L and on
are equipped with mechanical flap position
indicators. Refer to Section 7 for details.

16-63.

TROUBLE SHOOTING FLAP INDICATION SYSTEM.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

FLAP POSITION INDICATOR FAILS TO RESPOND.
Popped circuit breaker.

Check visually.

Reset circuit breaker. If it pops
out again, determine cause and
correct.

Defective circuit breaker.

Check continuity.

Replace circuit breaker.

Defective wiring.

Check continuity.

Repair wiring.

Defective position transmitter.

Disconnect "hot" wire to transmitter. Check transmitter for
varying resistance as transmitter arm is moved.

Replace transmitter.

Defective position indicator.

If there is voltage to the indicator, continuity through wires,
and transmitter is good, indicator is defective.

Replace indicator.

16-40

PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

FLAP POSITION INDICATOR READINGS ERRONEOUS.
Position transmitter not ad-

See paragraph 7-18.

Adjust per paragraph 7-18.

Defective position transmitter.

Substitute known-good transmitter and check operation.

Replace transmitter.

Defective position indicator.

Substitute known-good indicator and check operation.

Replace indicator.

Loose electrical connection.

Check connections.

Tighten loose connections.

Justed properly.

16-63. WING LEVELER. A wing leveler system
consisting of a turn coordinator, pneumatic servos
and connecting cables and hoses- may be installed as
optional equipment. The turn coordinator gyro
senses changes in roll attitude, then electrically
meters vacuum power from the engine-driven vacuum
pump to the cylinder-piston servos, operating the
ailerons for longitudinal stability. The Model 150
has in addition to the aileron servos, two servos
connected to the rudder cables. These servos provide lateral (yaw) stability that prevents excessive
changes in heading in turbulent air. Manual control
of the system is afforded by the roll trim knob. The
roll trim should not be used to correct faulty rigging
or "wing heaviness". Manual override of the system
may be accomplished without damage to the aircraft
or system. The ON-OFF valve controls the vacuum
supply to the distributor valve, but does not affect
the electrically operated turn coordinator gyro.

Installation of the wing leveler system does not
change the vacuum relief valve settings specified in
paragraph 16-32.
The system may be removed and installed while
using figure 16-11 as a guide and observing general
precautions outlined in this section. Refer to appropriate publication issued by the manufacturer for
trouble shooting procedures.
16-64. RIGGING. The aileron servos are rigged by
positioning the left aileron up, then pulling the servo
cable until the piston is extended and the seal is taut
but not stretched. Holding this position, attach the
servo cable to the aileron cable as shown in applicable figure. Repeat procedure for right wing. The
Model 150 rudder servos are rigged by holding full
rudder and pulling the servo cable to extend the inactive servo until taut but not stretched,then securing
this cable as shown. Hold opposite rudder and rig
remaining servo in a similar manner.

SHOP NOTES:

16-41

1. Servo
2. Rudder Cable
3. Left Aileron Vacuum Hose...
4. Rudder Vacuum Hose
6.
7.
8.
9.
10.
11.
12.
13.
14.

16-42

Roll Trim Control
Aileron Cable
Bellcrank
ON-OFF Control
Suction Gage
Gyro Hose
Right Aileron Vacuum Hose
Inverter
Vacuum Relief Valve

System 'A' is used when navigation
gyros are not installed. System 'B'
uses a vacuum system common to
the navigation gyros and the turn

Figure 16-11. Wing Leveler Control System (Sheet 1 of 4)

NOTE
Torque hose mounting nuts (3) to
12-14 lb inches and cable clamp (6)
to 70-90 lb inches when installing.
The optional gyro system and the
wing leveler system obtain vacuum

Bellcrank

Knob
9. Roll-Trim
Turn Coordinator
10.

4.
8. Servo
Clamp.

11.
13. Inverter
Filter

PUM.

Right Aileron Vacuum Hose

2. Left Aileron Vacuum Hose

DirectCable

14. Suction Gage
15. ON-OFF Control

.......
i-..

Figure 16-11. Wing Leveler Control System (Sheet 2 of 4)

16-43
16-43

NOTE
//^^^^^,^/^
/System
"-*--

J 4 /A

1.
2.
3.
4.
5.
6.
7.

Battery
Battery Box Cover
Battery Contactor
Screw
Positive Battery Cable
Star Washer
Contactor Jumper Wire

8.
9.
10.
11.
12.
13.
14.

Washer
Nut
Diode Wire
Lockwasher
Wire to Master Switch
Power Cable to Bus
Negative Ground Strap

15. Bolt
16. Drain Tube
17. Tube Clamp
18. Battery Box
19. Cable to Starter Contactor
20. Check Wire
21. Gnd Ser Recpt Cable

Figure 17-3. Tailcone Installation of Battery
17-5

17-4. REMOVAL AND REPLACEMENT OF BATTERY. (See figure 17-1, 17-2 or 17-3.)
NOTE
Steps a thru c of the following procedure apply
to the tailcone battery installation only. The
remaining steps apply to both the firewall and
tailcone battery installations,
a. Remove the rear baggage compartment panel.
b. Loosen the snap fasteners on the floor pan.
c. Remove the floor pan.
d. Remove the battery box cover.
e. Disconnect the ground cable from the negative
battery terminal.
CAUTION
When installing or removing battery always
observe the proper polarity with the aircraft
electrical system (negative to ground). Reversing the polarity, even momentarily, may
result in failure of semiconductor devices
(alternator diodes, radio protection diodes
and radio transistors).
Always remove the battery ground cable
first and replace it last to prevent accidental short circuits.
f. Disconnect the cable from the positive terminal
of the battery.
g. Lift the battery out of the battery box.
h. To replace the battery, reverse this procedure.

should not be added to the solution. The water, however will decompose into gases and should be replaced regularly. Add distilled water as necessary
to maintain the electrolyte level with the horizontal
baffle plate or the split ring on the filler neck inside
the battery. When "dry charged" batteries are put
into service fill as directed with electrolyte. When
the electrolyte level falls below normal with use, add
only distilled water to maintain the proper level. The
battery electrolyte contains approximately 25% sulphuric acid by volume. Any change in this volume
will hamper the proper operation of the battery.

CAUTION
Do not add any type of "battery rejuvenator"
tothe electrolyte. When acid has been spilled
ed by following instructions published by the
Association of American Battery Manufacturers.
17-7. TESTING THE BATTERY. The specific
gravity of the battery may be measured with a
hydrometer to determine the state of battery charge.
If the hydrometer reading is low, slow-charge the
battery and retest. Hydrometer readings of the
electrolyte must be compensated for the temperature
of the electrolyte. Some hydrometers have a builtin thermometer and conversion chart. The following
chart shows the battery condition for various hydrometer readings with an electrolyte temperature of
80 ° Fahrenheit.
BATTERY HYDROMETER READINGS

17-5. CLEANING THE BATTERY. For maximum
efficiency the battery and connections should be kept
clean at all times.
a. Remove the battery and connections in accordance with the preceding paragraph.
b. Tighten battery cell filler caps to prevent the
cleaning solution from entering the cells.
c. Wipe the battery cable ends, battery terminals
and the entire surface of the battery with a clean
cloth moistened with a solution of bicarbonate of
soda (baking soda) and water.
d. Rinse with clear water, wipe off excess water
and allow battery to dry.
e. Brighten up cable ends and battery terminals
with emery cloth or a wire brush.
f. Install the battery according to the preceding
paragraph.
g. Coat the battery terminals with petroleum jelly
or an ignition spray product to reduce corrosion.
17-6. ADDING ELECTROLYTE OR WATER TO THE
BATTERY. A battery being charged and discharged
with use will decompose the water from the electrolyte by electrolysis. When the water is decomposed
hydrogen and oxygen gases are formed which escape
into the atmosphere through the battery vent system.
The acid in the solution chemically combines with the
plates of the battery during discharge or is suspended
in the electrolyte solution during charge. Unless the
electrolyte has been spilled from a battery, acid
17-6

1. 280
1.250
1.220
1. 190
11. 160

Specific
Specific
Specific
Specific
Specific

Gravity
Gravity
Gravity
Gravity
Gravity

100% Charged
75% Charged
50% Charged
25% Charged
Practically Dead

NOTE
All readings shown are for an electrolyte temperature of 80 ° Fahrenheit. For higher temperatures the readings will be slightly lower.
For cooler temperatures the readings will be
slightly higher.
17-8. CHARGING THE BATTERY. When the battery is to be charged, the level of the electrolyte
should be checked and adjusted by adding distilled
water to cover the tops of the internal battery plates.
Remove the battery from the aircraft and place in a
well ventilated area for charging.

WARNING
When a battery is being charged, and oxygen
gases are generated. Accumulation of these
gases can create a hazardous explosive condition. Always keep sparks and open flame
away from the battery.

Allow unrestricted ventilation of the battery
area during charging.
The main points of consideration during a battery
charge are excessive battery temperature and
violent gassing. Test the battery with a hydrometer to determine the amount of charge. Decrease the charging rate or stop charging temporarily if the battery temperature exceeds 125°F.
17-8A. BATTERY BOX. The battery is completely
enclosed in a box which is painted with acid proof
paint. The box has a vent tube which protrudes
through the bottom of the aircraft allowing battery
gases and spilled electrolyte to escape. The battery
box is riveted to the forward side of the firewall in
150 and 172 models and to the mounting brackets in
the tailcone in 180, 185 and 182 models.
17-8B. REMOVAL AND REPLACEMENT OF BATTERY BOX. (See figure 17-1, 17-2 or 17-3.) The
battery box is riveted to the firewall or to the mounting brackets in the tailcone. The rivets must be
drilled out to remove the box. When a battery box
is installed and riveted into place, all rivets and
scratches inside the box-should be painted with acidproof lacquer Part No. CES 1054-381, available
from the Cessna Service Parts Center.
17-9. MAINTENANCE OF BATTERY BOX. The
battery box should be inspected and cleaned periodically. The box and cover should be cleaned with a
strong solution of bicarbonate of soda (baking soda)
and water. Hard deposits may be removed with a
wire brush. When all corrosive deposits have been
removed from the box, flush it throughly with clean
water.

WARNING
Do not allow acid deposits to come in contact
with skin or clothing. Serious acid burns may
result unless the affected area is washed immediately with soap and water. Clothing will
be ruined upon contact with battery acid.
Inspect the cleaned box and cover for physical damage
and for areas lacking proper acid proofing. A badly
damaged or corroded box should be replaced. If the
box or lid require acid proofing, paint the area with
acid proof lacquer Part No. CES 1054-381, available
from the Cessna Service Parts Center.
17-10. BATTERY SOLENOID. The battery solenoid
is bolted to the side of the battery box. The solenoid
is a plunger type contactor which is actuated by turning the master switch on. When the master switch is
off, the battery is disconnected from the electrical
system, A silicon diode is used to eliminate spiking
of transistorized radio equipment. The large terminal of the diode connects to the battery terminal of
the battery solenoid. The small terminal of the diode
and the master switch wire connect to the minus terminal of the solenoid coil. On 1968 models a nylon
cover has been added to the solenoid terminals to
prevent accidental short circuits. (See item 18,
figure 17-2A).

17-10A. REMOVAL AND REPLACEMENT OF BATTERY SOLENOID. (See figure 17-1, 17-2, or 17-3.)
a. Open battery box and disconnect ground cable
from negative battery terminal. Pull cable clear of
battery box.
b. Remove the nut, lockwasher and the two plain
washers securing the battery cables to the battery
solenoid.
c. Remove the nut, lockwasher and the two plain
washers securing the wire which is routed to the
master switch.
d. Remove the bolt, washer and nut securing each
side of the battery solenoid to the firewall. The
solenoid will now be free for removal.
e. To replace the solenoid, reverse this procedure.
17-10B. SPLIT BUS POWER RELAY. A power relay is installed behind the instrument panel on all
aircraft utilizing a split bus bar. The relay is a
normally closed type, opening when external power
is connected or when the starter is engaged, thus
removing battery power from the electronic side
of the split bus and preventing transient voltages
from damaging the electronic installations.
17-10C. MASTER SWITCH. The operation of the
battery and alternator systems is controlled by a
master switch. The switch is a rocker type with
double-pole, double-throw contacts. The switch,
when operated, connects the battery solenoid coil
ground and the alternator field circuit to the battery,
activating the power systems. The master switch is
located on the stationary instrument panel.
17-10D. GROUND SERVICE RECEPTACLE. A
ground service receptacle is offered as optional
equipment on all models except the 150 to permit the
use of external power for cold weather starting or

when performing lengthy electrical maintenance.
On late model aircraft a reverse polarity protection,
utilizing blocking diodes, has been incorporated into
the ground service receptacle. Power from the external power source will flow only if the ground
service plug is correctly connected to the airplane.
If the plug is accidentally connected backwards, no
power will flow to the airplane's electrical system,
thereby preventing any damage to electrical equipment.
Before connecting an external power source, it is
important that the master switch be turned "ON. "
This will close the battery contactor and enable the
battery to absorb transient voltages which might
damage the electronic equipment.
NOTE
An older aircraft not having the battery
contactor closing circuit, if it is suspected
that the battery is too weak to close the
battery contactor as the master switch is
turned "ON, " turn on the dome light or
similar equipment to check battery contactor
operation. If the contactor did not close
the dome light will not illuminate and it will
be necessary to momentarily "jumper"
17-7

182

1. Receptacle
2. Screw
3. Washer
4. Lockwasher

5. Moun
Receptacle
Figure 17-4. Ground Service
17-8

9.
10.
11.
12.

5. Mounting Nut
6. Mounting Bracket
7. Ground Strap
8. Terminal Nut
lation (Sheet

Power Cable
Nipple
Doubler
Cover Plate

of 3)

- ,,CHX

1967 & ON 172 MODELS

1.
2.
3.

Screw
Receptacle
Diode Board

4.
5.
6.

Figure 17-4.

Power Cable
Nut
Rivet

7.
8.
9.

Bracket Assembly
Washer
Ground Strap

Ground Service Receptacle Installation (Sheet 2 of 3)
17-9

across the two large battery contactor posts
to close the contactor as external power is
applied.

an external source opens the relay supplying
power to the electronic bus.

NOTE

17-10E. REMOVAL AND REPLACEMENT OF
GROUND SERVICE RECEPTACLE. (See figure 17-4.)
a. Open battery box and disconnect the ground cable
from the negative terminal of the battery and pull the
cable from the battery box.
b. Remove the nuts, washers, ground strap, bus

On late models having the reverse polarity
protection circuit, maintenance on the electronics installations can not be performed
when using external power. Application of

I3
4

j\f

6 i

- j

1967 & ON 180,
& 182 MODELS
3 s 185,
131
1967 & ON 180,
185, & 182 MODELS
6.
7.
8.
9.

1. Nipple
2. Lock Washer
3. Nut
4. Ground Strap
5. Washer
Figure 17-4.
17-10

Bracket Assembly
Rivet
Doubler Assembly
Cowl

Ground Service Receptacle Installation (Sheet 3 of 3)

10.
11.
12.
13.
14.

Door Assembly
Screw
Receptacle
Diode Board
Power Cable

bar and diode board from the stud of the receptacle
and remove the battery cable.
c. Remove the screws and nuts holding the receptacle. The receptacle will then be free from the
bracket.
d. To install a ground service receptacle, reverse
this procedure. Be sure to place the ground strap on
the negative stud of the receptacle.
17-11.

GENERATOR POWER SYSTEM.

17-12. GENERATOR. Generators used on Cessna
aircraft are two brush-shunt wound types with negative ground. The generator output is controlled by
the current passing thru the field winding of the
generator. The field winding is connected to the
17-13.

armature circuit of the generator internally and
must be grounded externally (by the regulator) for
the generator to operate. The generator is driven
either by a gear train in the engine accessory case
or by a V-belt. The output is 14 volts at 20, 35 or
50 amperes, depending upon the particular unit.
Three electrical connections are required for the
generator. Ground is provided thru the generator
case and mounting brackets. The field terminal is
connected thru the master switch to the voltage
regulator and the armature terminal connects directly to the voltage regulator. On some aircraft a
capacitor is attached to the armature terminal of the
generator. The capacitor suppresses any radio interference which might be created by the generator.

TROUBLE SHOOTING GENERATOR OR ALTERNATOR SYSTEM.

WARNING LIGHT OR AMMETER
INDICATES
INDICATES CORRECTLY
CORRECTLY

REMEDY

ISOLATION PROCEDURE

PROBABLE CAUSE
I

BATTERY DOES NOT COME UP TO FULL CHARGE

Blown fuse or circuit breaker.
(Generator models only.)

Inspect.

Reset or replace.

Loose drive belt.
(Some aircraft.)

Inspect.

Tighten belt.

Poor wiring connections.

Inspect.

Clean and tighten.

Faulty battery.

Test.

Replace.

Faulty regulator.

Test or substitute.

Adjust or replace.

Generator or alternator
output low.

Test or substitute. Check
alternator for faulty diode.

Repair. Replace diode plate
assembly.

Excessive power consumption.

Calculate electrical loading.

Install higher output system.

AMMETER DOES NOT DEFLECT
WARNING LIGHT DOES NOT COME ON

WHEN MASTER SWITCH IS TURNED ON.

Battery down.

Battery solenoid not closing.
Test battery.

Charge battery.

Blown fuse or circuit breaker.

Inspect.

Replace or reset.

Burned out lamp.

Try new lamp.

Replace.

Faulty wiring or battery
solenoid.

Test wiring and solenoid.

Repair or replace.

AMMETER DOES NOT SHOW CHARGE )
WARNING LIGHT DOES NOT GO OUT

WHEN ENGINE SPEED IS INCREASED.

Loose or broken drive belt.
(Some aircraft.)

Inspect.

Tighten or replace.

Loss of generator polarity.
(Does not apply to alternator.)

All components and wiring okay,
generator does not charge.

Restore residual magnetism by
polarizing generator.

Faulty voltage v-:gulator.

Test or substitute.

Adjust or replace.
17-11

17-13.

TROUBLE SHOOTING GENERATOR OR ALTERNATOR SYSTEM - Cont.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

AMMETER DOES NOT SHOW CHARGE
Faulty generator or alternator.

Test or substitute.

Replace.

Faulty circuit wiring.

Inspect and test.

Repair wiring.

ALTERNATOR OUTPUT CONTINUOUSLY HIGH.
Faulty-wiring.

Inspect-for-loose-ordirtyconnections.

Clean and tighten.

Regulator set too high.

Measure voltage output of
alternator.

Adjust or replace regulator.

Regulator faulty.

Substitute.

Adjust or replace.

ALTERNATOR CIRCUIT BREAKER OPENS WHEN MASTER SWITCH IS TURNED ON - ENGINE
NOT RUNNING.
Shorted diode inside
alternator.

Test diodes.

Replace diode assembly.

Short in wiring between
bus bar and alternator.

Test wiring for shorts.

Repair.

ALTERNATOR OUTPUT CONTINUOUSLY LOW.
Faulty wiring.

Inspect for loose or dirty connections.

Clean and tighten.

Faulty diode in alternator.

Test diodes.

Replace.

Faulty alternator winding.

Test.

Replace.

BATTERY CONSUMES WATER RAPIDLY.
Faulty battery.

Slow charge battery and load
test.

Replace.

Regulator set too high.

Measure alternator voltage
output.

Adjust voltage.

Shorted diode in alternator
causing battery to cycle.

Test diodes.

Replace diode and test regulator.

SHOP NOTES:

17-12

17-14. REMOVAL AND REPLACEMENT OF
GENERATOR - MODELS 180, 182 & 185. (See figure 17-5.)
a. The generator may be removed through the cowl
door. However, the job will be performed easier if
the top portion of the cowl is removed.
b. Release the clamp securing the generator blast
tube and remove the tube.
c. Remove the wiring from the generator.
d. Cut the safety wire securing the generator adjustment bolt and remove the bolt and washer. Leave
the generator belt in place to support the generator.
e. Remove the bolts, washers and nuts from the
bottom of the generator bracket and remove generator and drive belt.
f. To install the generator, reverse this procedure.
Adjust the drive belt for 3/8" deflection with a force
of 12 pounds applied.

17-16. REMOVAL AND REPLACEMENT OF OPTIONAL (HEAVY DUTY) GENERATOR ON MODEL
P172.
a. Remove the cowl from the aircraft and drain the
engine oil.
b. Block up the tail by placing a suitable support
under the tail tie-down ring.
c. Using a hoist attached to the engine hoisting lug
lift the engine only enough to relieve the tension on
the engine shock mount bolts.
NOTE
If the propeller is not removed, the engine will
be slightly nose heavy. A sling arranged between the engine crankshaft and hoist will be
necessary to balance the engine.
d.

1
0 1
CAUTION
-trols

If the generator has a filter capacitor connected for suppression of radio noise, be sure that
it is connected only to the armature terminal
of the generator. If the capacitor is accidentally connected to the field terminal, it will
cause arcing and burning of the voltage regulator contacts.
17-15. REMOVAL AND REPLACEMENT OF
STANDARD 20-AMPERE GENERATOR ON MODELS
172, P172 and 150.
a. Remove the cowl from the aircraft and drain the
oil (it is not necessary to drain the oil in the 150).
b. Loosen the clip securing the blast tube and pull
the tube clear of the generator.
c. Disconnect the generator wiring and pull it clear
of the generator area.
d Remove the three mounting nuts and washers
attaching the generator to the engine accessory case.
e. Remove the bolts, spacers and washers securing the generator to the manifold balance tube. Pull
the generator free from the engine and work the

generator out of the left side of the engine.
f.

Remove the engine shock mount bolts.

e. Disconnect any lines, electrical wiring, conor clamps which would interfere with lifting
the engine clear of its shock mounts and rotate the
rear of the engine downward approximately two inches. Secure the engine in this position.
CAUTION
Use care not to damage any parts when moving
the engine.
f. Disconnect the electrical wiring from the generator.
g. Release the generator blast tube clamp and pull
the tube clear of generator.
h. Remove the three nuts and washers attaching the
generator to the engine accessory case.
i. Remove the bolts, spacers and washers attaching the generator to the intake manifold balance tube.
and remove the generator from engine.
j. To replace the generator, reverse this procedure.

CAUTION

To replace the generator, reverse this procedure.

[CAUT-ION

Before replacing the generator, carefully inspect the oil seal on the front of the generator.
If there is any sign of wear or deterioration,
replace the seal. A leaky seal will cause loss
of engine oil.
If the generator has a filter capacitor connected
for the suppression of radio noise, be sure that
it is connected only to the armature terminal
of the generator. If the capacitor is connected
to the field terminal, it will cause arcing and
burning of the voltage regulator contacts.
17-17. POLARIZING THE GENERATOR. A generator of the type used on aircraft must maintain a
residual magnetism in the pole shoes in order to
produce a charge. Whenever any work is performed
on the basic electrical system the generator should
be polarized to make sure a charge will be produced.
17-13

To polarize a generator connect a jumper momentarily between the ARMATURE and BATTERY terminals of the regulator before starting the engine. A
momentary surge through the generator is enough to
correctly polarize it.

If a generator is not correctly polarized the
regulator and generator may be damaged.
Do not polarize alternator systems.
17-18. GENERATOR VOLTAGE REGULATOR. The
regulator is a vibrating contact type containing three
relays. The voltage and current limiting relays control the output of the generator according to the demand of the battery. This control of the generator is
accomplished by changing the amount of-field-current
flowing through the generator. The maximum current output of the generator is controlled by the current limiting relay. If the current output of the generator exceeds a preset amount the current limiting
relay interrupts the generator field circuit reducing
the output by inserting a resistance into the field circuit. Similar conditions apply for generator output
voltage control. When the generator is not producing, such as in an idle condition it is necessary to
disconnect the battery from the generator. If the
generator is not disconnected during no output conditions the armature appears as a path to ground for
the battery voltage. To prevent this loss of battery
potential the cutout relay portion of the regulator
disconnects the battery from the armature circuit
when the charging voltage drops below a specified
level and current begins to flow in a reverse direction. The operation of the voltage regulator controls
the output of the generator with respect to certain
preset maximum levels, however the regulator must
be informed of the batteries condition to taper the
charge and prevent overcharging. This informationis
supplied to the regulator by the battery counter electromotive force on the regulator. The rate of charge
is determined by the voltage limiting relay. The
higher the battery's charge, the higher the charging
voltage must be and the most effect the voltage
limiter will have on the charging rate. This reduces
the charging rate as the battery comes up to charge.
17-19. GENERATOR WARNING LIGHT. The generator warning light is provided to indicate when the
generator is not charging the battery. The light is
electrically connected across the cutout relay contacts of the voltage regulator. Whenever the cutout
contacts are open the light will measure the potential
difference between the battery and the generator armature. When the battery voltage is in excess of the
generator output (such as an idling condition) the
light will come on. As the generator speed (output)
is increased, the potential difference across the light
will diminish and the light will grow dim. When the
cutout relay connects the generator output to the battery the light circuit is bypassed through the voltage
regulator and the light will go out.
17-20. AMMETER. The ammeter is connected
between the battery and the aircraft bus. The meter
indicates the amount of current flowing either to or
17-14

from the battery. With a low battery and the engine
operating at cruise speed, the ammeter will show
the full generator, or alternator, output. When the
battery is fully charged and cruise is maintained
with all electrical equipment off, the ammeter will
show a minimum charging rate.
17-21. ALTERNATOR POWER SYSTEM. The introduction of the high current silicon diode resulted in
a reduction of mass making the alternator suitable
for light aircraft use. The alternator power system
provides a high power output with a low engine speed
and a reduction in weight. The alternator, like the
generator, produces an ac voltage by electromagnetic induction. Rectification of the ac is accomplished by the silicon diodes. The alternator system does not require external current regulation.
The-currentregulation of the alternator is inherent
and overloading results in a power drop off due to
magnetic saturation. The alternator system requires
an external exciting voltage to create a magnetic
field around the rotor poles before power may be
derived.
17-22. ALTERNATOR. Alternators used on Cessna
single engine aircraft are three phase with integral
silicon diode rectifiers. Early alternators are rated
14 volts at 52 amperes continuous output. Alternators currently being installed on single engine aircraft are rated 14 volts at 60 amperes continuous
output. The moving center part of the two alternators (rotor) consists of a radial winding and interlocking poles which surround the winding. With
excitation applied to the winding through slip rings
the pole pieces assume magnetic polarity. The rotor
is mounted in bearings and rotates inside the stator
which is the stationary part of the alternator. The
stator contains three phase windings and six silicon
diodes. As the magnetic lines (created by exciting
the rotor with a dc voltage) cut the stator windings
an alternating voltage is produced. The alternating
voltage from the three phase windings of the stator
is fed into six diode rectifiers which are arranged
electrically to provide full wave rectification. The
diodes output is dc and is combined and applied to the
aircraft bus bar and also to the voltage regulator
for sensing. The alternators are mounted on the
left rear section of the engine and are belt driven.
For maintenance of the alternators, refer to the
"Cessna Alternator Charging Systems Service/Parts
Manual."
-D A M
AGE.
17-23. ALTERNATOR REVERSE-VOLTAGE
The alternator is very susceptible to reverse polarity
current because of the silicon diodes. The diodes,
having a very high resistance to reverse current flow
are used without any cutout relay such as used on a
generator system. The alternator diodes are arranged with their cathodes connected to the aircraft
bus bar which is positive and no back current will
flow. If the polarity of the battery is reversed the
diodes will offer no resistance to the current flow.
The current rating of the diodes is exceeded and
diode failure may result.

17-24. ALTERNATOR VOLTAGE REGULATOR.
The alternator voltage regulator contains two relays.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

Palnut
Nut
Washer
Lower Forward Generator Bracket
Upper Generator Bracket
Lower Aft Generator Bracket
Bolt
Drive Belt
Generator
Brush Cover Band

Figure 17-5.

Generator Installation

NOTE
LATE MODEL ALTERNATORS HAVE A
BUILT-IN RADIO NOISE SUPPRESSOR.

Radio Noise
Suppressor
4. Clamp
5. Adjusting
Bracket
6. Alternator
7. Nut
8. Support Assy

Thru 1966 Models - All Models Except 150 & 172

Figure 17-6.

Belt-Driven Alternator Installation
17-15

1. Clamp
-2--Hose3. Blast Tube Support
4. Lock Washer
5. Screw
6. Support Strap

9
-

7. Nut
8.
9.
10.
11.
12.
13.

Alternator Assy
Washer
Clamp
Clamp Half
Bolt
Support Strap

Figure 17-7.

1.
2.
3.
4.
5.
6.

Hose
Blast Tube Support
Clamp
Lock Washer
Screw
Support Strap

Model 150 Gear-Driven Alternator Installation

7. Nut
8. Alternator Assembly
9. Gear Drive Assembly
10. Washer

Figure 17-8.
17-16

Model 172 Gear-Driven Alternator Installation

^ ^

1.
2.
3.
4.
5.

Alternator
Adjusting Bracket
Mounting Bolt
Mounting Bracket
Drive Belt

1968 & On - Model 172 Only

Figure 17-8A.

Model 172 Belt Driven Alternator Installation

SHOP NOTES:

17-16A/17-16B

1. Bolt
2.
3.
4.
5.
6.
7.

Washer
Adjusting Bracket
Alternator
Nut
Support Assembly
Bushing

2/
1
/

1967 & On - All Models Except 150 & 172

Figure 17-9.

Shock-Mounted Alternator Installation

One relay is actuated by the aircraft master switch
and connects the regulator to the battery. The
second relay is a two-stage voltage regulator which
controls the field current to the alternator. The
voltage limiter relay vibrates to provide a variable
control of the field current depending upon the load.
The limiter relay is compensated for temperature
variation to provide increased charging during cold
weather operation.
17-25. REMOVAL AND REPLACEMENT OF
ALTERNATOR ON MODELS 180, 182 AND 185.
a. Make sure the master switch remains in the off
position or disconnect the negative lead from the
battery.
b. Disconnect the wiring from the alternator.
c. Remove the safety wire from the upper adjusting bolt and remove the bolt from the alternator.
d. Remove the nut and washer from the lower
mounting bolt.
e. Remove the alternator drive belt and lower
mounting bolt to remove alternator.
f. To replace alternator reverse this procedure.
g. Adjust belt tension to obtain 3/8" deflection at

the center of the belt when applying 12 pounds of
pressure. After belt is adjusted and the bolt is safety wired, tighten the bottom bolt to 50-70 lb. -lb.
torque to remove any play between alternator mounting foot and U shaped support assembly. Whenever
a new belt is installed, belt tension should be checked
within 10 to 25 hours of operation.
-

ICA UT IO N
When tightening the alternator belt, apply
pry bar pressure only to the end of the alternator nearest to the belt pulley.
17-25A. REMOVAL AND REPLACEMENT OF GEARDRIVEN ALTERNATOR.
a. Insure that master switch is off and that negative lead is disconnected from battery.
b. Remove wiring from alternator and label.
c. Remove nuts and washers from alternator
mounting bolts.
d. Remove alternator.
e. To replace alternator, reverse this procedure.
17-17

17-26.

AIRCRAFT LIGHTING SYSTEM.

17-27. The aircraft lighting equipment consists of
landing and taxi lights, navigation lights, flashing
17-28.

and rotating beacon lights, dome and instrument
flood lighting, map lighting, instrument post lighting, compass lighting and radio dial lighting.

TROUBLE SHOOTING THE LIGHTING SYSTEM.
PROBABLE CAUSE

ISOLATION PROCEDURE

REMEDY

LANDING OR TAXI LIGHT OUT.
Circuit breaker open.

Inspect.

Reset.

Lamp burned out.

Test with voltmeter or new
lamp;

Replace lamp.

Defective wiring.

Test circuit for continuity.

Repair wiring.

Defective switch.

Check for continuity.

Replace.

Defective circuit breaker.

Test with voltmeter.

Replace.

Lamp burned out.

Inspect.

Replace lamp.

Defective wiring.

Check continuity.

Replace wiring.

Circuit breaker open.

Inspect.

Reset.

Faulty switch.

Test for continuity.

Replace.

Defective wiring between
circuit breaker and switch.

Test for continuity.

Repair.

ONE NAVIGATION LIGHT OUT.

ALL NAVIGATION LIGHTS OUT.

ROTATING BEACON WILL NOT OPERATE.
Circuit breaker open.

Inspect.

Reset breaker.

Defective wiring.

Check continuity of wiring from
aircraft bus to rotating beacon
plug.

Repair wiring.

Defective beacon.

Repair or replace beacon.-

FLASHING BEACON DOES NOT LIGHT.
Lamp burned out.

Test with new lamp.

Replace lamp.

Circuit breaker open.

Inspect.

Reset.

Faulty Flasher assembly.

Remove and test.

Repair or replace.

Faulty switch or wiring.

Test for continuity.

Repair or replace.

Circuit breaker open.

Inspect.

Reset.

Lamp burned out.

Test with new lamp.

Replace lamp.

Faulty switch or wiring.

Test for continuity.

Repair or replace.

DOME LIGHT TROUBLE.

17-18

1. WINDOW

3. LAMP

5. BRACKET

17-19

2 3

7 i

21l^

!7
6.21f^^^
Le

7 -'12
tni
W

'10
11

..... ............

23{L

Figure 17-11.
17-20

....

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.

Cap
Grounding Washer
Insulating Washer
Spring
Insulator
Lamp Socket
Screw
Lens Retainer
Lens
Lamp
Gasket
Clamp

13.
14.
15
16.
17.
18.
19.
20.
21.
22.
23.
24.

Navigation Lights and Rotation Beacon Installation

Detector
Contaet
Bracket
Glove Box
Flasher
Nut
Washer
Globe
Deflector
Clamp
Wire Clip
Disconnect

~~~~*

Screw

10.

Housing - Plug

15.

Inspection
Plate
13

12.
13.
14.

Fin
Assembly
Flasher
Assembly
Spacer

'----------------

107. Socket Assembly
~
8. Nutplate

2. Gasket
3.
4.Lamp
Clamp Assembly

9. Tip Assembly - Fin

.--

Figure 17-12.

& ON

Model 150 Flashing Beacon Light Installation (Sheet 1 of 4)
3lamp Figure
las g 1-2.Model150
Bo

(Sheet

17-21
17-21

1.
2.
3.
4.
5.
6.

Dome
Gasket
Lamp
Screw
Baffle
Clamp Assembly

7.
8.
9.
10.
11.
12.

Plate - Mounting
Socket Assembly
Nut Plate
Tip Assembly - Fin
Housing- Plug
Housing - Cap

13.
14.
15.
16.
17.
18.

Fin Assembly
Bulkhead
Lock Washer
Nut
Shock Mount
Flasher Assembly

Figure 17-12. Model 172 Flashing Beacon Light Installation (Sheet 2 of 4)
17-22

20
1. Dome
2. Gasket
3. Lamp
4. Clamp Assembly
5. Screw
6. Baffle
7. Plate-Mounting

Figure 17-12.

8.
9.
10.
11.
12.
13.

Socket
Nut Plate
Tip Assembly - Fin
Housing - Plug
Housing- Cap
Fin Assembly

19Thru51967 Models
14. Flasher Assembly
15. Lock Washer
16. Shock Mount
17. Nut
18. Plate
19. Washer
20. Grommet

Model 180-185 Flashing Beacon Light Installation (Sheet 3 of 4)
17-23

1.
2.
3.
4.
5.

Dome
Gasket
Lamp
Screw
Baffle

6. Clamp Assembly
7. Socket Assembly
8. Nutplate
9. Tip Assembly - Fin
10. Spacer

Figure 17-12.
17-24

12.
13.
14.
15.

11.
Flasher Assembly
Fin Assembly
Housing - Cap
Housing - Plug
Plate
-

Model 182 Flashing Beacon Light Installation (Sheet 4 of 4)

17-28.

TROUBLE SHOOTING THE LIGHTING SYSTEM.
PROBABLE CAUSE

(Cont)

ISOLATION PROCEDURE

REMEDY

MAP OR INSTRUMENT FLOOD LIGHT TROUBLE.
Lamp burned out.

Test with new lamp.

Replace.

Circuit breaker open.

Inspect.

Reset.

Rheostat open.

Test for continuity.

Replace.

Faulty wiring.

Test for continuity.

Repair.

Faulty circuit breaker.

Test with voltmeter.

Replace.

Burned out lamp.

Test with new lamp.

Replace lamp.

Faulty lamp socket or wiring.

Test with voltmeter.

Repair or replace.

ONE OR TWO POST LIGHTS OUT.

ALL POST LIGHTS, COMPASS LIGHT AND RADIO DIAL LIGHTS OUT IN CIRCUIT.
Circuit breaker open.

Inspect.

Reset.

Faulty section in dropping
rheostat.

Lights will work when knob
is placed in brighter position.

Replace rheostat.

Faulty wiring.

Test for continuity.

Repair wiring.

Faulty circuit breaker.

Test for continuity.

Replace breaker.

Faulty wiring between
circuit breaker and circuit
board.

Check for approximately
13 volts dc at terminal 7
of terminal block under
control wheel.

Repair or replace wiring.

Faulty circuit board.

Voltage check above will show
if voltage is present.

Replace.

CONTROL WHEEL MAP LIGHT.

17-28A. LANDING AND TAXI LIGHTS. The landing
and taxi lights are mounted in the leading edge of the
left wing. A clear plastic cover provides weather
protection for the lamps and is shaped to maintain
the leading edge curvature of the wing. The landing
lamp is mounted on the inboard side and adjusted to
throw its beam further forward than the taxi light.
Both lights are controlled by a simaea switch.

c. Remove the two screws securing the wiring to
the lamp contacts and remove the lamp.
d. Install new lamp and reassemble.

17-28B. REMOVAL AND REPLACEMENT OF LANDING AND TAXI LIGHTS. (See figure 17-10.)
a. Remove the 18 screws securing the landing
light window assembly (1) and the assembly will
then be free for removal.
b. Remove the four attaching screws (7) from the
bracket assembly and remove the bracket.

17-28D. REMOVAL AND REPLACEMENT OF NAVIGATION LIGHTS. For removal and replacement of
navigation lights refer to figure 17-11.

NOTE
Do not repl'--ion the landing and taxi light
adjustment screws (3). If readjustment is

required refer to figure 17-10.

17-28C. NAVIGATION LIGHTS. The navigation
lights are located on each wing tip and the top edge
of the vertical fin. The lights are controlled by a
pull type switch located on the instrument panel.

17-28E. ROTATING BEACON. The rotating beacon
contains a small motor which rotates a shutter containing three lens openings around a single bulb to
give a flashing warning of the aircraft's position.
The beacon is installed in a fiberglass mounting
atop the vertical fin on all models thru 1966.
17-25

,4
4

3 Al

... |

jS
12.

r17-26

Figure 17-13.

Figure 17-13.
17-26

4.
Reflector
5.
8. Socket
Cover

13.
117. Spacer
Rheostat

Bracket
59.
LeADJUSTNG
7..':':''.
1. Tinnerman Nut 3/
2. Grommet
Grommet

18.
10.
11.
11.

Instrument, Map & Utility Lighting

"Knob
SCREW

Washer
Nut.
Nut.

5. Socket

14. Spring

6.
7.
8.
9.

15.
16.
17.
18.

Bulb
Lens
Cover
Bracket

Instrument, Map & Utility Lighting

Switch
Shield
Rheostat
Knob

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

Nut
Washer
Grommet
Adjustment Screw
Maplight Assembly
Socket Assembly
Lamp
Red Lamp
Lens

'-A

7
9

Hood/

Nut

11. Screw
12. Front Doorpost ShieldJ
13. Maplight Switch
14.

~~~~~~~~~~~~~~~~~~~~2

0^^

1o'

1
12
se,

Figure 17-14. Map Light Installation
17-28F. REMOVALAND REPLACEMENT OF ROTATING BEACON. For removal and replacement
of the rotating beacon refer to figure 17-11.
17-28G. FLASHING BEACON. All 1967 models and
on have a flashing beacon light attached to a thermoformed plastic mounting on the vertical fin. The
flashing beacon is an iodine-vapor lamp electrically
switched by a solid-state flasher assembly. The
flasher assembly is located in the aft section of the
tail cone on 150, 172, 180 and 185 models and in the
vertical fin on 182 models. The switching frequency
of the flasher assembly operates the beacon at approximately 45 flashes per minute.
17-28H. REMOVAL AND REPLACEMENT OF
FLASHING BEACON LIGHT. For removal and
replacement of the flashing beacon refer to figure
17-12.
17-28J. OVERHEAD CONSOLE. On Models 150,
172, 180 and 185 the interior lights console contains
a dome light and an instrument light that provide
cabin lighting and red, non-glare instrument flood
lighting. The dome light consists of a frosted lens

and a single bulb controlled by a switch located in
the center of the console. The instrument flood light
consists of a red lens and a single bulb that is controlled by a dimming rheostat mounted on the right
side of the console.
The Model 182 overhead console contains a map
light and an instrument flood light. The intensity
of the instrument flood light is controlled by a rheostat mounted on the instrument panel. The map light
can be exposed by moving the slide covers from the
opening holes on the console.
17-28K. REMOVAL AND REPLACEMENT OF OVERHEAD CONSOLE. For removal and replacement of
the overhead console refer to figure 17-13.
17-28L. MAP LIGHTING. White map lighting and
red, non-glare instrument lighting are provided by
an adjustable light mounted on the forward part of
the left door post. The switch is a three position
type with red, white and off positions. The map
light contains a white bulb for general purpose
lighting and a red bulb for adjustable instrument
lighting. The intensity of the red bulb is controlled
by the instrument light dimming rheostat on the
overhead console.
17-27

1.
2.
3.
4.
5.

Stationary Panel Assembly
Control Wheel Assembly
Shield
Circuit Board
Screw

Figure 17-15.
17-28

6.
7.
8.
9.
10.

Grommet
Clamp
Cable Assembly
Resistor
Stand-Off

12.
13.
14.
15.
16.

Light
Rheostat
1/2 Amp - Fuse Assembly
Nut
Terminal Block

Control Wheel Map Light Installation - Model 172 Only

1.
2.
3.
4.
5.

1/2 Amp - Fuse Assembly
Terminal Block
Screw
Nut
Clamp

Figure 17-16.

6.
7.
8.
9.

Stationary Panel Assembly
Control Wheel Assembly
Cable Assembly
Shield

//7.

10.
11.
12.
13.
14.

Resistor
Circuit Board
Diode
Light
Rheostat

Control Wheel Map Light Installation - Models 180 & 185 Only
17-29

2
4
5

1.
2.
3.
4.

Cable Assembly
1/2 Amp - Fuse Assembly
Terminal Block
Sta-Strap

Figure 17-17.
17-30

5.
6.
7.
8.
9.

Bracket
Screw
Shield
Resistor
Circuit Board

10.
11.
12.
13.

Diode
Light
Rheostat
Control Wheel Assembly

Control Wheel Map Light Installation - Model 182 Only

1.
2.
3.
4.
5.
.
7.
8.
9.
10.

Figure 17-18.

Stall Warning Horn
Bracket
Tinnerman Nut
Screw
Stall Warning Transmitter
Wing Leading Edge
Pitot Tube
Heater Element
Nut
Insulating Washer

Stall Warning & Pitot Heater Systems
17-31

17-28M. REMOVAL AND REPLACEMENT OF MAP
LIGHT. (See figure 17-14.)
a. For replacement of defective lamp slide the
hood and lens from the map-light assembly and remove the bayonet type bulb.
b. For removal of the map light assembly remove
the screws from the front doorpost shield. Remove
the washer and nut attaching the map light. Remove
the ground wire from the map light screw. Detach
the wires at the quick disconnect fasteners and remove the map light assembly.
17-28N. INSTRUMENT POST LIGHTING. Individual
post lights may be installed as optional equipment for
Cessna white, non-glare instrument lighting. The
_post light consists of a cap and clear lamp assembly
with a tinted lens-.The-intensity-of-the-instrument
post lights is controlled by the radio light dimming
rheostat mounted on the lower left side of the instrument panel.
17-28P. REMOVAL AND REPLACEMENT OF POST
LIGHTS. For removal of the post lamp slide the cap
and lens assembly from the base. Slide the lamp
from the socket and replace.
17-28Q. COMPASS AND RADIO DIAL LIGHTING.
The compass and radio dial lights are contained within the individual units. The light intensity is controlled by the radio light dimming rheostat, mounted
on the lower left side of the instrument panel on 182
models and on the overhead console on 150, 172, 180
and 185 models.
17-28R. CONTROL WHEEL MAP LIGHT. An
optional control wheel map light may be installed on
all 1968 models except the Model 150. The map
light is mounted on the underside of the control wheel
and the light intensity is controlled by a thumb operated rheostat. For dimming, the rheostat should be
turned clockwise.
17-28S. REMOVAL AND REPLACEMENT OF CONTROL WHEEL MAP LIGHT ASSEMBLY. (See figures
17-15, 17-16 & 17-17.)
a. For easy access of the map light assembly,
rotate the control wheel 90°.
b. Remove the four screws from the map light circuit board. The map light assembly will then be free
for removal from the control wheel.
c. Label the wires connecting to the map light circuit board assembly and remove the screws securing
the wires to the circuit board assembly.

17-32

d. To install the map light assembly, reverse this
procedure.
17-29.

STALL WARNING SYSTEM.

17-30. The stall warning circuit is comprised of a
warning horn and an actuating switch. The switch is
installed in the leading edge of the left wing and is
actuated by airflow over the surface of the wing. The
switch will close as a stall condition is approached,
actuating the warning horn which is mounted on the
glove box. The stall warning unit should actuate the
stall warning horn approximately five to ten miles
per hour above airplane stall speed. Install the lip
of the warning unit approximately one-sixteenth of
an inch below the center line of the wing skin cutout. Test fly the aircraft to determine if the unit
actuates the warningihorn-at-the-desired-speed.If the unit actuates the horn at a speed in excess of
ten miles per hour above stall speed, loosen the
mounting screws and move the unit down. If the unit
actuates the horn five miles an hour below stall speed,
loosen the screws and move the unit up.
On 150 Models 1966 & on, 172, 180 & 185 Models
1967 & on, these aircraft have incorporated a reed
type horn which is actuated directly by airflow
ducted from the wing leading edge. The system is
described in Section 16, paragraph 16-53A. No
heating provisions are used.
17-31. PITOT AND STALL WARNING HEATER CIRCUTS.
17-32. Electrical heater units are incorporated in
some pitot tubes and stall warning switch units. The
heaters offset the possibility of ice formations on the
pitot tube and stall warning actuator switch. The
heaters are integrally mounted in the pitot tube and
stall warning actuator switch. Both heaters are
controlled by the pitot heat switch.
17-33. CIGAR LIGHTER. Some aircraft are equipped
with an extra circuit protection device in addition to
the primary circuit breaker. The cigar lighter may
have a special thermal-actuated cutout which is
attached to the rear of the cigar lighter socket. The
cutout will open the circuit if the lighter becomes
jammed in the socket or held in the heat position
too long. The cutout may be reset by inserting a
small rod through the smallhole in the cutout and
pressing the spring into reset position.

ELECTRICAL LOAD ANALYSIS CHART
FOR ALL 1964 & 1965 MODELS
AMPS REQD

ELECTRICAL EQUIPMENT

150

172

180

182

185

Battery Contactor ........................
0.8
0.88
0.8
0.8
Carburetor Air Temperature Indicator .............
. .0.03
0.03 0.03
0.03
Cigarette Lighter. .................
........
10.0 10.0 10.0 10.0
10.0
Clock . .............
.............
Negligible
Courtesy Lights and Cabin Lights .....
....
....
....
3.3
Courtesy Lights and Dome Light ..............
...
2.5
2.5
2.5
2.5
Cylinder Head Temperature Indicator .
.
........
....
0.18 0. 18 0.18 0. 18
Flap Motor
.........
.....
15.0
15.0 15.0
Flap Position Indicator ...........
....
......
0. 26
0. 26
Fuel Quantity Indicators .
.................
..
0.36 0.36 0.36
0.36 0.36
Generator Light ...
. . ..
. ..
. ...
..
......
. . ..
0.4
0. 4
Heaters, Stall Warning & Pitot

......

............

8.6

H.F. Antenna Reel Motor . .
...................
Instrument Lights:
Cluster (1965 & on only)
.
...................
*Console . . . . . . . . . . . . . . . . . . . . . . . . . . .
Compass . ........................
..
Landing Lights. ...
.......................
Map Light. ..
...........
.........
...
Navigation Light .........................
OiDilution System. .......................
Pictorial Gyro Indicator Lights (1964 only) .
............
*Post Lighted Panel Installation (1965 & on only) .....
......
Rotating Beacon .......................
Stall Warning Horn .
....
...........
......
Turn &Bank Indicator ........
.....
. ..
Vertical Adjusting Seats
.......
.
........
Cessna ADF 300 (Type R-521) .
...........
Cessna ADF 500 (Type R-318-1964 Only) .............
Cessna ADF 500 (Type-R-318-1965 Only) .......
Cessna Marker Beacon 300 (Type R-521-1964 Only) ...
Cessna Marker Beacon 300 (Type R-521-1965 Only) .........
Cessna Nav/Com 300 (Type RT-513)
.
.
...
Cessna 1 1/2 Nay/Corn 300 & 300R (Types RT-514A & RT-514R)

Cessna Nav/Com 500 (Type RT-317)
....
Cessna Nav/Omni 500 (Type R-319)
.
............
Cessna Nav-O-Matic 200 Autopilot
......
..
Cessna Nav-O-Matic 300 Autopilot ..
......
Cessna Transceiver 500 (Type RT-302A-1964 Only) .........
Cessna Transceiver 500 (Type RT-302G & H-1965 Only) ......
King KA-10 Isolation Amplifier ..
.0.5
King KN-60 DME.

...

8.6

14.0

1.1

0.3
1.1

1.6

0. 2
0.17
6.5

4. 3
0. 2
0.17
6.5

1.6 1.6
4. 3
4.3
4.3
0. 2
0. 2
0.17
0. 17
6.5
6.5

4.5

4. 5

2.0
2.0

5. 2
0
2.0
2.0

5. 2
7.0
2. 0
2. 0

0. 5

5.2
0.5

5. 2
7. 0
2. 0
2.0
5 0
5.2
0.5

5.0

6.4
6.0
4.0
4.0
5.2

6.4
6.0
4.0

6.4
6. 0
4.0

5.2
7.5
2. 5
5.8
4.7

5. 2
7.5
2. 5
5.8
4.7

5.2
7. 5
2. 5
5.8
4.7

1.1
15.6
5.6

4.
.25
0.2

0.3
0.3
2.0
1.1
0. 08
15.6 15.6 15.6 15.6
0.33 0.33
0.33 0.33
5.6
5.6
5.6
5.6
1.0
1.0
1.0
1.0
0.08
0.08
1.6
4.8
. 4.8
4.8
.25
.25
.25
.25
0.2
0.2
0.2
0.2
20.0

.4.5

.............

King KX-120 with KI-200 Indicator
.
.....
King KX-150A & KX-150AE ...
King KY-95 ...........
.....
Narco Mark IV Superhomer ......
Narco Mark XI with VOA-4, -5, or -6 Indicator ...
Narco UDI-2 DME Receiver .
.
.........
Narco UGR-1A Glideslope Receiver ........
Pantronics DX10-D ....
Sunair T-5-DA .
.
....

8.6

14.0

...

6.0
4.0
0
5. 2

5
5.8

5.2
0. 5

*A switching arrangement prevents the console lights from being operated at the same time the post lights
are operated.
17-33

ELECTRICAL LOAD ANALYSIS CHART
FOR ALL 1966 MODELS
AMPS REQD
ELECTRICAL EQUIPMENT
Battery Contactor ....................
Carburetor Air Temperature Indicator ..............
...........
Cigarette Lighter ............
. . . . . . . . . . . . . . . . . . . . . . . .
Clock
Courtesy Lights and Cabin Lights ....
Courtesy Lights and Dome Light .................
Cylinder Head Temperature Indicator ..............
...............
......
FlapMotor .
...................
Flap Position Indicator
....................
Fuel Quantity Indicators
Generator Light . . . . . . . . . . . ......
. ..
Heaters, Stall Warning & Pitot .................
H.F. Antenna Reel Motor ....................
Instrument Lights:
Cluster . . . . . . . . . . . . . . . . . . . . . .
*Console . .......................
.......................
Compass
......
......
. . . . . . . . . ...
Landing Lights
Map Light ..........................
Navigation Light .....................
..
.............
Oil Dilution System . . . ...
...............
.
*Post Lighted Panel Installation .
Rotating Beacon . .......................
..............
Stall Warning Honr ..
...........
Turn & Bank Indicator ..........
..................
.
Vertical Adjusting Seats .

150

172

0.6

0.66
0.03
10.0

10.0
. . . .Ne
2.5
.

15.0
.

. . . .
.

..
..

0.33
0.4
8.6

1.1
0.1
15.6
0.33
5.6
4.0

....

..
0.2

0.8
..
...............
Bendix ADF-T12C ......
1.6
Cessna ADF 300 (Type R-521) . . ...............
Cessna ADF 500 (Type R-318) . .................
0.17
Cessna Marker Beacon 300 (Type R-521) .............
4.5
Cessna 1 1/2 Nav/Com 300 & 300R (Types RT-516A & RT-515R) . .
...
.......
.
Cessna Nav/Com 500 (Type RT-317) .
5.0
.............
Cessna Nav/Omni 300 (Type RT-525)
...
.
........
Cessna Nav/Omni 500 (Type R-319) .
2.0
.
Cessna Nav-O-Matic 200 Autopilot ................
Cessna Nav-O-Matic 300 Autopilot ................
.3.0
Cessna Nav-O-Matic 400 Autopilot . .............
Cessna Transceiver 500 (Type RT-302). .............
0.5
King KA-10 Isolation Amplifier .................
. . . . . . . . . . . . . . .5.0
. . . . . . .
King KN-60 DME
4.7
King KX-150B & KX-150BE ...................
3.0
.
. . . ...
. .....
. . . . . . . ..
King KX-160E . ..
4.0
...
..
. ..
. ....
King KY-95 . . . . . . . . . . . ..
Pantronics DX10-DA ......................

180

182

185

0.6
0.6
0.6
0.03 0.03
0.03
10.0
10.0 10.0
ligible
3............
3
2.5
2.5
2.5
0.2
0. 2
0.2
15.0
15.0
0.1
0.1
0. 33
0.33
0. 33 0.33
0.4
8.6
8.6
8.6
8.6
14.0
14.0 14.0
14.0
1.1
0.1
15.6
0.33
5.6
1.0
4.0
25
0.2

0.8
1.6
0.17
4.5
5.0
2.0
2.0
0.5
4.7
3.0
4.0
6.5

0.3
0.3
2.0
1.1
0.1
0.1
15.6 15.6
0.33 0.33
5.6
5.6
1.0
1.0
1.6
4.0
4.0
.25
.25
0.2
0.2
20.0

0.3
1.1
0.1
15.6
0.33
5.6
1.0

0.8
1.6
4.3
0.17
4.5
5.2
5.0
7.0
2.0
2.0
3.0
5.2
0.5
5.0
4.7
3.0
4.0
6.5

0.8
1.6
4.3
0.17
44.5
5.2
5.0
7.0
2.0
2.0
3.0
5.2
0.5
5.0
4.7
3.0
4.0
6.5

4.0
.25
0.2

*A switching arrangement prevents the console lights from being operated at the same time the post lights
are operated.
17-34

ELECTRICAL LOAD ANALYSIS CHART
FOR ALL 1967 MODELS

AMPS REQD
ELECTRICAL EQUIPMENT_-

150
Battery Contactor .
..................
........
0.6
Carburetor Air Temperature Indicator . .............
Cigar Lighter . . ...
...........
. . .
.....
10.0
Clock . . . ...
. . ...
. . .....
.
. . . ...
..
CourtesyLgh and
ndD
Dome Lights
.
. . . . . . . . . . . .
Cylinder Head Temperature Indicator ......
.....
. . .0.2
Flap Motor .................
..
. . ....
15.0
Flap Position Indicator .
................
. . . .
Flashing Beacon . ......

. . . . . . . . . . . . . . . . . .

Fuel Quantity Indicators . . . ..................
Heater, Pitot
...................
Heater, Stall Warning & Pitot ...................
H.F. Antenna Reel Motor .
..................
Instrument Lights:
Cluster
...............
. .
*Console .
. . . . . . . . . . . . . .
Compass ......
........
Landing Lights ........
.........
Map Light .
. . . . . . . . . . . . . . . .
Navigation Lights .....................
Oil Dilution System ...
. . . . . . . . . .
*Post Lighted Panel Installation .....
. . .
Stall Warning Horn ..
..........
Turn and Bank Indicator ...................

185
172
180
0.6
0.6
0.6
0.03 0.03
10.0 10.0 10.0
Negligible
2. 5
2.5
2.5
0.2
15.0
0. 1

Cessna ADF 300 (Type R-521) .................
Cessna ADF 500 (Type R-318) .............
Cessna DME 300 (Type KN-60) ................
Cessna Marker Beacon 300 (Type R-502B) .............
Cessna 1 1/2 Nav/Com 300R (Types RT-515R-1 & RT-517R)
Cessna Nav/Com 500 (Type RT-317) . .
. ..... ...
.
Cessna Nav/Omni 300 (Type RT-525) ...........
Cessna Nav/Omni 500 (Type R-319) ...
. . . . . . . .
Cessna Nav-O-Matic 300 Autopilot ......
.....
.
Cessna Nav-O-Matic 400 Autopilot. .
.. . . . . . .
Cessna Transceiver 300 (Type RT-524A) ...
......
Cessna Transceiver 500 (Type RT 302G) ...
. . . . . .
King KA-25C Isolation Amplifier .
..
. . . . . . . . .
King KX-150BE ..
............
King KX-160E, AE or AF.
. . .. . . . . . . . .
King KY-95E ...................
....
Narco Mark 12A with VOA-4 or -5 Indicator ............
Pantronics DX10-DA ...................

.
. . . .4.2
. .
.
.
.
.
.
.

. . . .
.
.
.
.

.
. .
.2.0
. .
..
. . . .
. . . .

7.0

0.4

0.4
0.4

6.5

0.4
6.5

10.0
14.0

. . . .
.4.0
. . .

0.2

25
0.2

.25
0.2

0.3
2.0
0.1
15.6
0.33
5.6
1.0
2.0
.25
0.2

1.6

0.02
5.5

5.0
0.02
5.5

6.0

3.2

3.0
3. 2

5.0
0.02
5.5
5.2
6.0
7.0
2.0
3.0
3.2
6.5
0.5
4.7
2.5
4.0
4.8
6.5

1.6
4.2
5.0
0.02
5.5
5.2
6.0
7.0
2. 0
3.0
3.2
6. 5
0. 5
4.7
2.5
4.0
4.8
6.5

1.6
4.2
5.0
0.02
5.5
5.2
6.0
7.0
2.0
3.0
3.2
6.5
0.5
4.7
2.5
4.0
4.8
6.5

1.1
0.1
15.6
5.6

0.3
0.3
1.1
1.1
1.1
0.1
0.1
0.1
15.6 15.6 15.6
0.33 0.33 0.33
5.6
5.6
5.6
1.0
1.0

.
.
.
.

3.3
0.2
15.0
0.1

7.0

.14.0
. . . . .
. . . . . . . . . .
...............
.....
..
. . . . . . . . . .
. .
. . . . . . . . . .
. . . . . . . . . .
...........
. .

182
0.6
0.03
10.0

0.5
4.7
2.5

0.5
4.7
2.5
4.0
4.8
6.5

*A switching arrangement prevents the console lights from being operated at the same time the
post lights are operated.

17-35

ELECTRICAL LOAD ANALYSIS CHART
FOR ALL 1968 MODELS

AMPS REQD
ELECTRICAL EQUIPMENT

150

0.6
. ........
Battery Contactor ..............
10.0
.....
Carburetor Air Temperature Indicator ........
.N
Cigaiette Lighter. ......................
Clock . . . . . . . . . . . . . . . . . . . . . . . . .3.3
Cii-rtesy-Lights-and-eabin-LightsCourtesy Lights and Dome Light .................
Cylinder Head Temperature Indicator ..............
.3
Dome Light . . . . . . . . . . . . . . . . . . . . . . . . . .
15.0
.
........
.....
...........
Flap Motor
.........
.
Flap Position Indicator .
7.0
........
Flashing Beacon Light. .............
0. 4
.
...
Fuel Quantity Indicators
6.5
.....
Heater - Pitot .
. .10.0
Heaters - Pitot & Stall Warning ..............
.....
1.1
....
Instrument Lights. .............
Instrument Lights:
Cluster
.
.....................
*Console
.
................
.
.
.............
Compass. .
.
Switch Panel
.
.
................
15.6
.
.
.....
.........
Landing Lights ......
..........................
Map Light ..
5.6
...
..............
Navigation Lights .
............
Oil Dilution Valve. ......
....
..
....
.... .............
*Post Lighted Panel
.
..
. ..
. ..
..
. . .......
Stall Warning Horn ..
0.2
.
. . ..
Turn & Bank Indicator. ...........
0. 8
Turn Coordinator. ....................

0.6
0.03
10.0

0.8
1.6

.
.
Brittain Wing Leveler. ...............
..
Cessna 300 ADF (Type R-521B.
Cessna 300 DME (Type KN-60B) .................
Cessna 300 Marker Beacon (Type R-502B). ............
Cessna 300 Nav/Corn - 90 Ch. (Type RT-517R) ..........
Cessna 300 Nav/Corn - 360 Ch. (Type RT-540A) ..........
Cessna 300 Transceiver (Type RT-524A) .............
......
.......
Cessna 300 Nav-O-Matic ..
.....
Cessna 400 ADF (Type R-318G-2) .
Cessna 400 Glide Slope (Type R-543B) ..............
.........
.
Cessna 400 Nav/Com (Type RT-522)
...
Cessna 400 Transceiver (Type RT-532) ...........
............
Cessna 400 Nav-O-Matic
King KA-25C Isolation Amplifier .................
.
KingKY-95E. .4.0.4.0......
.
.
..........
King KX-150BE. .
KingKX-160E or KX-160AE ...................
Narco Glide Slope Receiver UGR-2 ................
Narco Mark 12A with VOA-8 or VOA-9 ..............
..
.6.5
Pantronics DX10-DA ...................
Antenna Reel Motor. .14.0.............14.0

2.5
2.

0.6
0.03
10.0
gligibl
2. 5
0.2

0.6
0.6
0.03 0.03
10.0 10.0
2.5
0.2

15.0
0.1
7.0
0. 4
6.5

7.0
0. 4
6.5

7.0
0.4
6.5

1.1

1.4

0;8
15.0
0. 1
7.0
0. 4

15.6
33
5.6

15.6
.33
5.6

0.2
0.8

0.2
0. 8

0. 3
2.0
0.1
0.7
15.6 15.6
.33
.33
5.6
5.6
1.0
2.0
2.5
0.2
0.2
0.8
0.8

.02
5.5
5. 5
3.2

0.8
1.6
5.2
.02
5.5
5.5
3.2

0.5

0.5
4.0
4.7
2.5
0. 3
4.8

0.5
4.0
4.7
2.5

0.8
1.6
5.2
.02
5.5
5.5
3.2
2. 0
4.2
0.5
2.0
1.0
3.0
0.5
4.0
4.7
2.5
0.3
4.8
6.5
14.0

0.8
0.8
1.6
1.6
5.2
5.2
.02
.02
5.5
5.5
5.5
5.5
3.2
3.2
2.0
2.0
4.2
4.2
0.5
0. 5
2. 0
2.0
1.0
1.0
3.0
3.0
0.5
0.5
4.0
4.0
4.7
4.7
2.5
2.5
0.3
0. 3
4.8
4.8
6.5
6.5
14.0 14.0

*A switching arrangement prevents the console lights from being operated at the same time the post lights are
Operated.
17-36

SECTION 18
ELECTRONIC SYSTEMS

This section has been deleted from this book. The information formerly contained in this section may now be found
in one of the individual Cessna Electronic Manuals. For
installation, refer to the "Cessna Electronic Installations
and Service/Parts Manual." For repair, refer to the
appropriate Cessna Service/Parts Manual.

SECTION 19
STRUCTURAL REPAIR
TABLE OF CONTENTS

Page

REPAIR CRITERIA ...............................................
EQUIPMENT AND TOOLS ...................................
CONTROL BALANCING.......................................
SUPPORT STANDS..............................................
Fuselage Repair Jig .........................................
Wing Jig............................................................
WING AND STABILIZER ANGLE-OFINCIDENCE ...........................................................
REPAIR MATERIALS............................................
WING .....................................................................
Access ..............................................................
WING SKIN............................................................
Negligible Damage...........................................
Repairable Damage.........................................
Damage Necessitating Replacement of Parts.
WING STRINGERS...............................................
Negligible Damage...........................................
Repairable Damage.........................................
Damage Necessitating Replacement of Parts.
WING AUXILIARY SPARS....................................
Negligible Damage...........................................
Repairable Damage .........................................
Damage Necessitating Replacement of Parts.
WING RIBS............................................................
Negligible Damage...........................................
Repairable Damage .........................................
Damage Necessitating Replacement of Parts.
WING SPARS........................................................
Negligible Damage...........................................
Repairable Damage.........................................
Damage Necessitating Replacement of Parts.
WING LEADING EDGE.........................................
Negligible Damage...........................................
Repairable Damage .........................................
Damage Necessitating Replacement of Parts.
AILERONS.............................................................
Negligible Damage...........................................
Cracks in Corrugated Aileron Skins.................
Repairable Damage .........................................
Damage Necessitating Replacement of Parts.
WING FLAPS ........................................................
Negligible Damage...........................................
Cracks in Corrugated Flap Skins .....................
Repairable Damage .........................................
Damage Necessitating Replacement of Parts.

19-2
19-2
19-2
19-2
19-2
19-2
19-2
19-3
19-3
19-3
19-3
19-3
19-3
19-3
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4
19-4A
19-4A
19-4A
19-4A
19-4A
19-4A
19-4A
19-4A
19-4A
19-4B
19-4B
19-4B
19-4B
19-4B
19-4B
19-4B

ELEVATORS AND RUDDERS .........................
Negligible Damage.......................................
Cracks in Corrugated Elevator and Rudder
Skins ............................................................
Repairable Damage.....................................
Damage Necessitating Replacement of
Parts .............................................................
FIN AND STABILIZER
.
..........
.......................
Negligible Damage.......................................
Repairable Damage .....................................
Damage Necessitating Replacement of
Parts .............................................................
FUSELAGE .......................................................
Negligible Damage.......................................
Repairable Damage .....................................
Damage Necessitating Replacement of
Parts .............................................................
BULKHEADS.....................................................
Landing Gear Bulkheads .............................
REPAIR AFTER HARD LANDING ....................
REPLACEMENT OF HI-SHEAR RIVETS.........
FIREWALL DAMAGE........................................
ENGINE MOUNT..............................................
Description ........................................
General Considerations ...............................
Engine Mount Support Cradle Damage.......
Damage Involving Engine Mounting Lugs
and Engine Mount to Fuselage Attaching
Fittings..........................................................
Baffles ..................................
......
ENGINE COWLING ........................................
Repair of Cowling Skins...............................
Repair of Reinforcement Angles ..................
Repair of Thermo-Formed Plastic
Components.................................................
Repair of Glass Fiber Constructed
Components ........................................

19-1
Aug 4/2003

19-4C
19-4C
19-4C
19-4C
19-4C
19-4C
19-4C
19-4C
19-4D
19-4D
19-4D
19-4D
19-4D
19-4D
19-4E
19-4E
19-4E
19-4E
19-4E
19-4E
19-4E
19-4E
19-4E
19-4E
19-5
19-5
19-5
19-5
19-5
19-5

19-1.

REPAIR CRITERIA.

19-2.

Although this section outlines repair permissible on structure of the aircraft, the decision of whether
to repair or replace a major unit of structure will be influenced by such factors as time and labor
available, and by a comparison of labor costs with the price of replacement assemblies. Past
experience indicates that replacement, in many cases, is less costly than major repair. Certainly,
when the aircraft must be restored to its airworthy condition in a limited length of time, replacement
is preferable.

19-3.

Restoration of a damaged aircraft to its original design strength, shape, and alignment involves
careful evaluation of the damage, followed by exacting workmanship in performing the repairs. This
section suggests the extent of structural repair practicable on the aircraft and supplements Federal
Aviation Regulations, Part 43. Consult the factory when in doubt about a repair not specifically
mentioned here.

19-4.

EQUIPMENT AND TOOLS.

19-5.

Equipment and tools for repair of structure may be fabricated locally for all but major repair jobs. For
major repair of wings and fuselage, special jogs, available from the factory, are recommended.
These jigs are precision equipment designed to ensure accurate alignment of these airframe
components.

19-6.

CONTROL BALANCING.
Control balancing requires the use of a fixture to determine the static balance moment of the control
surface assembly. Plans for, and the use of, such a fixture are shown in figure 19-3.

19-7.

SUPPORT STANDS.
Support stands shown in figure 19-1 are used to hold a fuselage or a wing when it is removed. The
stands may be manufactured locally of any suitable wood.

19-8.

FUSELAGE REPAIR JIG.
The fuselage jig, which may be obtained from the factory, is a sturdy, versatile fixture used to hold
an entire fuselage and locate the firewall, wing, and landing gear attachment points. The jig is ideal
for assembling new parts in repair of a badly damaged fuselage.

19-9.

WING JIG.
The wing jig, which may also be obtained from the factory, serves as a holding fixture during
extensive repair of a damaged wing. The jig locates the root rib, leading edge, and tip rib of the
wing.

19-10. WING AND STABILIZER ANGLE-OF-INCIDENCE.
Angle-of-incidence and wing twist are listed in the following chart. Stabilizers do not have twist.
Wings have a constant angle from the wing root to the strut fitting station. All twist in the panel is
between this station and the tip rib. The amount of twist between these points is the difference
between the angle-of-incidence at the root and the angle-of-incidence at the tip. See figure 19-2.
MODEL

150
172 & 72
180 & 185
182

WING ANGLE-OF-INCIDENCE
ROOT
+1°
+1 ° 30'
+1 ° 30'
+1° 30'

WING TWIST
(WASHOUT)

STABILIZER ANGLEOF-INCIDENCE

1°
3°
3°
3°

-3°
-3° 30'
Adjustable
-3°

TIP
0°
-1° 30'
-1° 30'
-1 30'

Revision 1
Aug 4/2003

19-11. REPAIR MATERIALS.
19-12. Thickness of material on which a repair is to be made can easily be determined by measuring with a
micrometer. In general, material used in Cessna aircraft covered in this manual is made from 2024
aluminum alloy, heat treated to a -T3, -T4, or -T42 condition. If the type of material cannot be readily
determined, 2024-T3 may be used in making repairs, since the strength of -T3 is greater than -4 or T42 (-T4 and -T42 may be used interchangeably, but they may not be substituted for -T3). When
necessary to form a part with a smaller bend radius than the standard cold bending radius for 2024T4, use 2024-0 and heat treat to 2024-T42 after forming. The repair material used in making a
repair must equal the gage of the material being repaired unless otherwise noted. It is often
practical to cut repair pieces from service parts listed in the Parts Catalogs.
A few components (empennage tips, for example) are fabricated from thermo-formed plastic or glass
fiber constructed materials.
19-13. WING.
19-14. The wing assemblies are a semi-cantilever type employing semi-monocoque type of structure.
Basically, the internal structure consists of built-up front and rear spar assemblies, a formed auxiliary
spar assembly and formed sheet metal nose, intermediate, and trailing edge ribs. Stressed skin,
riveted to the rib and spar structures, completes the wing structure.
19-15. ACCESS.
Access openings (hand holds with removable cover plates) are located in the underside of the wing
between the wing root and the tip section. These openings afford access to aileron bellcranks, flap
bellcranks, electrical wiring, strut attaching fittings, aileron control cable pulley, and control cable
disconnect points.
19-16. WING SKIN.
19-17. NEGLIGIBLE DAMAGE.
Any smooth dents in the wing skin that are free from cracks, abrasions, and sharp corners, and
which are not stress wrinkles and do not interfere with any internal structure or mechanism, may be
considered as negligible damage. In areas of low stress intensity, cracks, deep scratches, or deep,
sharp dents, which after trimming or stop drilling can be enclosed by a two-inch circle, can be
considered negligible if the damaged area is at least one diameter of the enclosing circle away from
all existing rivet lines and material edges. Stop drilling is considered a temporary repair and a
permanent repair should be made as soon as practicable.
19-18. REPAIRABLE DAMAGE.
Figure 19-4 outlines typical repairs to be employed in patching skin. Before installing a patch, trim
the damaged area to form a rectangular pattern, leaving at least a one-half inch radius at each
corner, and de-burr. The sides of the hole should lie span-wise or chord-wise. A circular patch may
also be used. If the patch is in an area where flush rivets are used, make a flush patch type of
repair; if the patch is in an area where flush rivets are not used, make an overlapping type of repair.
Where optimum appearance and airflow are desired, the flush patch may be used. Careful
workmanship will eliminate gaps at butt-joints; however, an epoxy type filler may be used at such
joints.
19-19. DAMAGE NECESSITATING REPLACEMENT OF PARTS.
If a skin is badly damaged, repair should be made by replacing an entire skin panel, from one
structural member to the next. Repair seams should be made to lie along existing structural
members and each seam should be made exactly the same in regard to rivet size, spacing, and
pattern as the manufactured seams at the edges of the original sheet. If the manufactured seams
are different, the stronger seam should be copied. If the repair ends at a structural member where
Revision 1
© Cessna Aircraft Company

19-3
Aug 4/2003

no seam is used, enough repair panel should be used to allow an extra row of staggered rivets, with
sufficient edge margin, to be installed.
19-20. WING STRINGERS.
19-21. NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17.
19-22. REPAIRABLE DAMAGE.
Figure 19-5 outlines a typical wing stringer repair. Two such repairs may be used to splice a new
section of stringer material in position, without the filler material.
19-23. DAMAGE NECESSITATING REPLACEMENT OF PARTS.
If a stringer is so badly damaged that more than one section must be spliced into it, replace the
entire stringer.
19-24. WING AUXILIARY SPARS.
19-25. NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17.
19-26. REPAIRABLE DAMAGE.
Figure 19-8 outlines a typical auxiliary spar repair.
19-27.

DAMAGE NECESSITATING REPLACEMENT OF PARTS.
If damage to an auxiliary spar would require a repair which could not be made between adjacent
ribs, replace the auxiliary spar.

19-28.

WING RIBS.

19-29.

NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17.

19-30.

REPAIRABLE DAMAGE.
Figure 19-6 outlines typical wing rib repairs.

19-31.

DAMAGE NECESSITATING REPLACEMENT OF PARTS.
Leading and trailing edge ribs that are extensively damaged should be replaced. However, due to
the necessity of unfastening so much skin in order to replace ribs, they should be repaired if
practicable. Center ribs, between the front and rear spars, should always be repaired if practicable.

19-32. WING SPARS.
19-33.

NEGLIGIBLE DAMAGE.
Due to the stresses which wing spars encounter, very little damage can be considered negligible.
All cracks, stress wrinkles, deep scratches, and sharp dents must be repaired. Smooth dents, light
scratches, and abrasions may be considered negligible.

Revision 1
Aug 4/2003

19-34.

REPAIRABLE DAMAGE. Figure 19-7 outlines typical spar repairs. It is often practical to cut repair
pieces from spare parts listed in Parts Catalogs. Service Kits are available for certain types of spar
repairs.

19-35. DAMAGE NECESSITATING REPLACEMENT OF PARTS.
Damage so extensive that repair is not feasible requires replacement of a complete wing spar.
Refer to paragraph 19-2.
19-36. WING LEADING EDGE.
19-37.

NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17.

19-38.

REPAIRABLE DAMAGE.
A typical leading edge skin repair is shown in figure 19-9. An epoxy type filler may be used to fill
gaps at butt joints. To facilitate repair, extra access holes may be installed in the locations noted in
figure 19-10. If the damage would require a repair which could not be made between adjacent ribs,
refer to the following paragraph.

19-39.

DAMAGE NECESSITATING REPLACEMENT OF PARTS.
For extensive damage, complete leading edge skin panels should be replaced. To facilitate
replacement, extra access holes may be installed in the locations noted in figure 19-10.

19-40.

AILERONS.

19-41.

NEGLIGIBLE DAMAGE. Refer to paragraph 19-17.

19-41A. CRACKS IN CORRUGATED AILERON SKINS
1. It is permissible to stop drill crack(s) that originate at the trailing edge of the control surface
provided that the crack is not more than two inches in length.
2.

Stop drill crack using a #30 (0.128 inch) drill bit.

3. A crack may only be stop drilled once.
A crack that passes through a trailing edge rivet and does not extend to the trailing
edge of the skin may be stop drilled at both ends of the crack.

NOTE:

4. Any control surface that has a crack that progresses past a stop drilled hole shall be repaired.
NOTE:
5.

Refer to paragraphs 19-41, -42, and -43 as applicable for repair information.

A control surface that has any of the following conditions shall have a repair made as soon as
practicable:
A.

A crack that is longer than two inches.

A crack that does not originate from the trailing edge or a trailing edge rivet.

Cracks in more than six trailing edge rivet locations per skin.

NOTE:
6.

Refer to paragraphs 19-41, -42, and -43 as applicable for repair information.

Affected control surfaces, with corrugated skins and having a stop drilled crack that does not
extend past the stop drilled hole, may remain in service without additional repair.

Revision 1

Aug 4/2003

19-42.

REPAIRABLE DAMAGE.
The flush-type skin patches shown in figure 19-4 should be used to repair damage to an aileron
skin. Filler material for corrugated areas must match existing corrugations. Doubler material may
be flat. If damage would require a repair that could not be made between adjacent ribs, see the
following paragraph.

19-43.

DAMAGE NECESSITATING REPLACEMENT OF PARTS.
If the damage would require a repair that could not be made between adjacent ribs, complete skin
panels should be replaced. Ribs and spars may be repaired, but replacement is generally
preferable. Where extensive damage has occurred, replacement of the aileron assembly is
recommended. After repair and/or repainting, balance in accordance with figure 19-3.

19-44.

WING FLAPS.

19-45. NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17.
19-45A.CRACKS IN CORRUGATED FLAP SKINS
1. It is permissible to stop drill crack(s) that originate at the trailing edge of the control surface,
provided the crack is not more than two inches in length.
2. Stop drill crack using a #30 (0.128 inch) drill bit.
3. A crack may only be stop drilled once.
NOTE:
4.

A crack that passes through a trailing edge rivet and does not extend to the trailing
edge of the skin may be stop drilled at both ends of the crack.

Any control surface that has a crack that progresses past a stop drilled hole shall be repaired.
NOTE:

Refer to paragraphs 19-45, -46, and -47 as applicable for repair information.

5. A control surface that has any of the following conditions shall have a repair made as soon as
practicable:
A. A crack that is longer than two inches.
B. A crack that does not originate from the trailing edge or a trailing edge rivet.
C. Cracks in more than six trailing edge rivet locations per skin.
NOTE: Refer to paragraphs 19-45, -46, and -47 as applicable for repair information.
6.

Affected control surfaces with corrugated skins that have a stop drilled crack that does not
extend past the stop drilled hole, may remain in service without additional repair.

19-46. REPAIRABLE DAMAGE.
Flap repairs should be similar to aileron repairs discussed in paragraph 1942. A flap leading edge
repair is shown in figure 19-9.
19-47.

DAMAGE NECESSITATING REPLACEMENT OF PARTS.
Flap repairs that require replacement of parts should be similar to aileron repairs discussed in
paragraph 19-43.
Revision 1

Aug 4/2003

19-48. ELEVATORS AND RUDDERS.
19-49. NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17. The exception to negligible damage on the elevator surfaces is the front
spar, where a crack appearing in the web at the hinge fittings or in the tip which supports the
overhanging balance weight is not considered negligible. Cracks in the overhanging tip rib, in the
area at the front spar intersection with the web of the rib, also cannot be considered negligible.
19-49A. CRACKS IN CORRUGATED ELEVATOR AND RUDDER SKINS
1. It is permissible to stop drill crack(s) that originate at the trailing edge of the control surface
provided the crack is not more than two inches in length.
2.

Stop drill crack using a #30 (0.128 inch) drill bit.

A crack may only be stop drilled once.
NOTE:

A crack that passes through a trailing edge rivet and does not extend to the trailing
edge of the skin may be stop drilled at both ends of the crack.

4. Any control surface that has a crack that progresses past a stop drilled hole shall be repaired.
NOTE:
5.

Refer to paragraphs 19-49, -50, and -51 as applicable for repair information.

A control surface that has any of the following conditions shall have a repair made as soon as
practicable:
A. A crack that is longer than two inches.
B. A crack that does not originate from the trailing edge or a trailing edge rivet.
C. Cracks in more than six trailing edge rivet locations per skin.
NOTE: Refer to paragraphs 19-49, -50, and -51 as applicable for repair information.

Affected control surfaces with corrugated skins and having a stop drilled crack that does not
extend past the stop drilled hole, may remain in service without additional repair.

19-50. REPAIRABLE DAMAGE.
Skin patches shown in figure 19-4 may be used to repair skin damage. If the damaged area would
require a repair which could not be made between adjacent ribs, see the following paragraph.
19-51. DAMAGE NECESSITATING REPLACEMENT OF PARTS.
If the damaged area would require a repair which could not be made between adjacent ribs,
complete skin panels should be replaced. Ribs and spars may be repaired, but replacement is
generally preferable. Where extensive damage has occurred, replacement of the entire assembly is
recommended. After repair and/or repainting, balance in accordance with figure 19-3.
19-52. FIN AND STABILIZER
19-53. NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17

Revision 1

Aug 4/2003

19-54. REPAIRABLE DAMAGE.
Skin patches shown in figure 19-4 may be used to repair skin damage. Access to the dorsal area of
the fin may be gained by removing the horizontal closing rib at the bottom of the fin. Access to the
internal fin structure is best gained by removing skin attaching rivets on one side of the rear spar and
ribs, and springing back the skin. Access to the stabilizer structure may be gained by removing skin
attaching rivets on one side of the rear spar and ribs, and springing back the skin. If the damaged
area would require a repair which could not be made between adjacent ribs, or a repair would be
located in an area with compound curves, see the following paragraph.
19-55. DAMAGE NECESSITATING REPLACEMENT OF PARTS.
If the damaged area would require a patch which could not be made between adjacent ribs, or the
repair would be located in an area with compound curves, complete skin panels should be replaced.
Ribs and spars may be repaired, but replacement is generally preferable. Where damage is
extensive, replacement of the entire assembly is recommended.
19-56. FUSELAGE.
19-57. The fuselage is of semi-monocoque construction consisting of formed bulkheads longitudinal
stringers, reinforcing channels and skin platings.
19-58. NEGLIGIBLE DAMAGE.
Refer to paragraph 19-17. Mild corrosion appearing upon alclad surfaces does not necessarily
indicate incipient failure of the base metal. However, corrosion of all types should be carefully
considered, and approved remedial action taken. Small cans appear in the skin structure of all
metal airplanes. It is strongly recommended however, that wrinkles which appear to have originated
from other sources, or which do not follow the general appearance of the remainder of the skin
panels, be thoroughly investigated. Except in the landing gear bulkhead areas, wrinkles occurring
over stringers which disappear when the rivet pattern is removed may be considered negligible.
However, the stringer rivet holes may not align perfectly with the skin holes because of a permanent
"set" in the stringer. If this is apparent, replacement of the stringer will usually restore the original
strength characteristics of the area.
NOTE: Wrinkles occurring in the skin of the main landing gear bulkhead areas should not be
considered negligible. The skin panel should be opened sufficiently to permit a thorough
examination of the lower portion of the landing gear bulkhead and its tie-in structure.
Wrinkles occurring on open areas which disappear when the rivets at the edge of the sheet are
removed, or a wrinkle which is hand removable, may often be repaired by the addition of a1/2 x 1/2x
.060 inch 2024-T4 extruded angle, riveted over the wrinkle and extended to within 1/16 to 1/8 inch of
the nearest structural members. Rivet pattern should be identical to the existing manufactured seam
at the edge of the sheet.
19-59.

REPAIRABLE DAMAGE.
Fuselage skin repairs may be accomplished in the same manner as wing skin repairs outlined in
paragraph 19-18. Stringers, formed skin flanges, bulkhead channels, and similar parts may be
repaired as shown in figure 19-5.

19-60. DAMAGE NECESSITATING REPLACEMENT OF PARTS.
Fuselage skin repairs may be accomplished in the same manner as the wing repairs outlined in
paragraph 19-19. Damaged fittings should be replaced. Seat rails serve as structural parts of the
fuselage and should be replaced if damaged.

Revision 1
Aug 4/2003

19-61. BULKHEADS.
19-62. LANDING GEAR BULKHEADS.
Since these bulkheads are highly stressed members irregularly formed to provide clearance for
control cables, fuel lines, etc., the patch-type repairs will be, for the most part, impractical. Minor
damage, consisting of small nicks or scratches, may be repaired by dressing out the damaged area,
or by replacement of rivets. Any other such damage should be repaired by replacing the landing
gear support assembly as an aligned unit.
19-63. REPAIR AFTER HARD LANDING.
Buckled skin or floorboards and loose or sheared rivets in the area of the main gear support will give
evidence of damage to the structure from an extremely hard landing. When such evidence is
present, the entire support structure should be carefully examined and all support forgings should be
checked for cracks, using a dye penetrant and proper magnification. Bulkheads in the area of
possible damage should be checked for alignment and a straightedge should be used to determine
deformation of the bulkhead webs. Damaged support structure, buckled floorboards and skins, and
damaged or questionable forgings should be replaced.
19-64. REPLACEMENT OF HI-SHEAR RIVETS.
Replacement of Hi-shear rivets with close tolerance bolts or other commercial fasteners of
equivalent strength properties is permissible. Holes should not be elongated, and the Hi-shear
substitute should be a smooth push fit. Forgings may be spot-faced the least amount necessary for
proper seating of fasteners.
19-65. FIREWALL DAMAGE.
Firewall damage may be repaired by removing the damaged material and splicing in a new section
of material. The new portion should be lapped over the old material, sealed with Pro-Seal #700
(Coast Pro-Seal Co., Chemical Division, 2235 Beverly Blvd., Los Angeles, CA), or equivalent
compound, and secured with stainless steel rivets. Damaged or deformed angles and stiffeners
may be repaired as shown in figure 19-11, or they may be replaced. A severely damaged firewall
should be replaced as a unit.
19-66. ENGINE MOUNT.
19-67. DESCRIPTION.
The mount for the aircraft engine is constructed of 4130 chrome-molybdenum steel tubing. A truss
structure, fastened to the firewall at four points, supports a cradle arrangement. This cradle
arrangement, with its supporting lugs, forms the base for rubber shock mounted engine supports.
19-68. GENERAL CONSIDERATIONS.
All welding on the engine mount should be of the highest quality since the tendency of vibration is to
accentuate any minor defect present and cause fatigue cracks. Engine mount members are
preferably repaired by using a large diameter replacement tube, telescoped over the stub of the
original member, using fishmouth and rosette type welds. However, reinforced 30-degree scarf
welds in place of the fishmouth welds are considered satisfactory for engine mount repair work.
19-69. ENGINE MOUNT SUPPORT CRADLE DAMAGE.
Minor damage such as a crack adjacent to an engine attaching lug may be repaired by rewelding the
cradle tube and extending a gusset past the damaged area. Extensively damaged parts should be
replaced.
19-70. DAMAGE INVOLVING ENGINE MOUNTING LUGS AND ENGINE MOUNT TO FUSELAGE
ATTACHING FITTINGS.
Engine mounting lugs and engine mount to fuselage attaching fittings should not be repaired but
should be replaced.
Revision 1
© Cessna Aircraft Company

19-4E
Aug 4/2003

19-71. BAFFLES.
Baffles ordinarily should be replaced if damaged or cracked. However, small plate reinforcements
riveted to the baffle will often prove satisfactory both to the strength and cooling requirements of the
unit.
19-72. ENGINE COWLING.
19-73. REPAIR OF COWLING SKINS.
If extensively damaged, complete sections of cowling should be replaced. Standard insert-type
patches, however, may be used if repair parts are formed to fit. Small cracks may be stop-drilled
and dents straightened if they are reinforced on the inner side with a doubler of the same material.
19-74. REPAIR OF REINFORCEMENT ANGLES.
Cowl reinforcement angles, if damaged, should be replaced. Due to their small size, they are easier
to replace than to repair.
19-75. REPAIR OF THERMO-FORMED PLASTIC COMPONENTS.
19-76. Repair of puncture or holes in thermo-formed plastics can be made by trimming out the damaged
area, removing any paint in the area, and installing an overlapping, beveled, or flush patch of
identical material. Doublers may be installed behind the patch where additional strength is desired.
MEK, or any commercially available solvent that will soften and dissolve the plastic, may be used as
the bonding agent. Dissolving some of the plastic shavings in the solvent will furnish additional
working time. Moderate pressure is recommended for best results. Curing time will vary with the
agent used, but repairs should not be strained until fully cured. Cracks can be repaired by saturating
the crack itself with the solvent, then filling with an epoxy filler or a paste made of the plastic
shavings and the solvent. Again, the crack may be reinforced with a doubler on the back side for
additional strength. After the repair has been made, the area may be sanded smooth and painted.
Parts that are extensively damaged should be replaced instead of repaired.
19-77. REPAIR OF GLASS FIBER CONSTRUCTED COMPONENTS.
19-78. Glass fiber constructed components on the aircraft may be repaired as stipulated in instructions
furnished in SK182-12. observe the resin manufacturer's recommendations concerning mixing and
application of the resin. Epoxy resins are preferable for making repairs, since epoxy compounds are
usually more stable and predictable than polyester and, in addition, give better adhesion.

19-5
Aug 4/2003

12 INCH WIDE HEAVY CANVAS

1 X 12 X 30-3/4

1X 12 X 48

30-3/4

1 X 12 X 11
1 X 12 X8
2 X 4X 20
1-1/2
14

5 INCH COTTON
1X 4

3/8 INCH DIAMETER BOLTS
2X4
2 X 6

1 X 4

ALL DIMENSIONS

Figure 19-1. Wing and Fuselage Support Stands

Revision 1
Aug 4/2003

GRIND

A or B

MODEL

WING STATION

150
150

2.00
1.38

1.00
1.00

29.50
24.00

39.00
191.00

172 & P172
172 & P172

2.00
.59

1.00
1.00

29.50
24.00

39.00
207.00

180 & 185
180 & 185

2.00
.59

1.00
1.00

29.50
24.00

39. 00
207.00

182
182

2.00
.59

1.00
1.00

29.50
24.00

39. 00
207.00

MEASURING WING TWIST
If damage has occured to a wing, it is advisable to check the twist. The following method can be usedwith
a minimum of equipment, which includes a straightedge (32" minimum length of angle, or equivalent), three
modified bolts for a specific wing, and a protractor head with level.
1.

Check chart for applicable dimension for bolt length (A or B).

Grind bolt shanks to a rounded point as illustrated, checking length periodically.

Tape two bolts to straightedge according to dimension C.

Locate inboard wing station to be checked and make a pencil mark approximately one-half inch aft of
leading edge skin.

Holding straightedge parallel to wing station, (staying as clear as possible from "cans"), place longer
bolt on pencil mark and set protractor head against lower edge of straightedge.

Set bubble in level to center and lock protractor to hold this reading.

Omitting step 6, repeat procedure for outboard wing station, using dimensions specified in chart.
Check to see that protractor bubble is still centered.

Proper twist is present in wing if protractor readings are the same (parallel).
may be lowered from wing . 10 inch maximum to attain parallelism.

Figure 19-2.

Forward or aft bolt

Checking Wing Twist
19-7

GENERAL NOTES
1.

Balance control surfaces in a draft-free area.

Place hinge bolts through control surface hinges, and position on knife edge balancing mandrels.
Insert aileron hinges into slot in end of mandrels.

Make sure all control surfaces are in their final flight configuration: painted (if applicable),
trim tabs installed, all foreign matter removed from inside of control surface, elevator trim
tab push-pull rod installed, and all tips installed.

Place balancing mandrels on a table or other suitable flat surface.

Adjust trailing edge support to fit control surface being balanced while center of balancing
beam is directly over hinge line. Remove balancing beam and balance the beam itself by
adding washers or nuts as required at end opposite the trailing edge support.

When positioning balancing beam on control surface, avoid rivets to provide-a-smooth-surfacefor the beam, and keep the beam 90 ° to the hinge line of the control surface.

Paint is a considerable weight factor. In order to keep balance weight to a minimum, it is
recommended that existing paint be removed before adding paint to a control surface. Increase
in balance weight will also be limited by the amount of space available and clearance with
adjacent parts. Good workmanship and standard repair practices should not result in unreasonable balance weight.

The approximate amount of weight needed may be determined by taping loose weight at the
balance weight area.

Lighten balance weight by drilling off part of weight.

10.

Make balance weight heavier by fusing bar stock solder to weight after removal from control
surface. The ailerons should have balance weight increased by ordering additional weight and
attaching bracket listed in applicable Parts Catalogs, and installing the minimum length necessary for correct balance, except that a length which contains at least two attaching rivets
must be used. If necessary, lighten new weight and/or existing weights for correct balance.

BALANCING BEAM
Mark graduations in inches .

Four-foot length of extruded channel
Grind weight to slide along beam, grind
ends to obtain exactly one pound, and
mark center of weight.
Fabricate vertically adjustable
slide along beam.

Attach knife edges and
mark at mid-point.

Figure 19-3.
19-8

Control Surface Balancing (Sheet 1 of 3)

SLOT

Place directly over hings
line of control surface.

Adjust vertically until
beam

parallels aileron chord line,
which passesthrough a point

1/3 up at cemer span of

support, balance by adding
washersand/or nuts.

control
surface on balancing mandrels.
hings
bolts resting on
Position balancing beam with mid-point directly
over, and 90° to, hinge line.

Figure 19-3. Control Surface Balancing (Sheet 2 of 3)

19-9
Aug 4/2003

AILERONS

RUDDER

RIGHT ELEVATOR

LEFT ELEVATOR

Underbalance
(Inch-Pounds)

0.0 to + 8.94

0.0 to +41.47

0.0 to +35.41

0.0 to +29.05

150D & 150E

Same as above

0.0 to +6.94

0.0 to +13.31

0.0 to +13.29

150F, 150G & 150H

Same as above

0.0 to +6.0

Same as above

0.0 to +11.31

0.0 to +6.3

0.0 to +24.5

0.0 to +18.5

Same as above

0.0 to +13.80

Same as above

0.0 to +9.69

Same as above

0.0 to +9.64

0.0 to +3.8

0.0 to +17.21

180G & 180H

0.0 to +4.30

Same as above

182F & 182G

0.0 to +9.64

0.0 to +6.0

0.0 to +20.20

Same as above

182H, 182J,
182K & 182L

Same as above

0.0 to +20.47

0.0 to +4.30

0.0 to +16.18

0.0 to +17.21

Models & Serials

150C

172D & P172D
172E
172F to 17252001
F172F to F172-0120
172F 17252001 & on
F172F F172-0120 &
on
172G, 172H & 1721
180F

185 & A185 Series

NOTE:
The "Underbalance" columns list the tolerances within which the control
surface must balance. These tolerances must never be exceeded in the final
flight configuration.

Figure 19-3. Control Surface Balancing (Sheet 3 of 3)

Revision 1
Aug 4/2003

NOTE

SECTION THRU ASSEMBLED PATCH

pled skin and patch, and countersunk doubler.

EDGE MARGIN = 2 X RIVET DIA.

EDGE MARGIN =
2 X RIVET DIA.

FLUSH RECTANGULAR PATCH
SIMILAR)
REPAIR PARTS IN CROSS SECTION

Figure 19-4.

SKIN GAGE

RIVET DIA.

025

1/8

.040
051

1/8
5/32

Skin Repair (Sheet 1 of 6)
19-11

1/2 B
SECTION THRU ASSEMBLED PATCH

A-A

.....
EDGE MARGIN = 2 X RIVET DIA.

DOUBLER -

PARTS IN CROSS SECTION

2024-T3 ALCLAD

EREPAIR .040

Figure 19-4. Skin Repair (Sheet 2 of 6)
19-12

1/8

PATCHES AND DOUBLERS 2024-T3 ALCLAD

MS20470AD4 RIVETS
24 REQD

6. 50 DIA.
43. 00

PATCH

DIA-.-

D
7.50 DIA.

EXISTING
SKIN

SECTION THRU PATCH

3.00 DIA. HOLE

PATCH REPAIR FOR 3 INCH DIAMETER HOLE
MS20470AD4 RIVETS

-22

16 REQD

1/2

-4.00DIA.

3.00 DIA-.

2.00

PATCH

DOUBLER

EXISTING
2.00 DIA. HOLE/

DIA.
SECTION THRU PATCH

HEXSI

PATCH REPAIR FOR 2 INCH DIAMETER HOLE
MS20470AD4 RIVETS

EXISTING

8 REQD

SKIN

2.50 DIA.
CU -

PATCH
(NO DOUBLER
REQD)

DIA.

1.00 DIA. HOLE

SECTION THRU PATCH

PATCH REPAIR FOR 1 INCH DIAMETER HOLE

OVERLAPPING

CIRCULAR PATCH

Figure 19-4.

Skin Repair (Sheet 3 of 6)
19-13

NOTE
DOUBLER

dimple skin and patch.

DOUBLER-\
DOUBLER
EXISTING/
SKIN J

Countersink doublers, and

/
4

PATCH

T.
%..

RIVET PATTERN

~^ >

4-8D

CPITCH

EDGE DISTANCE

2D MIN.

_~ DOUBLER-

W .~*.-';

TICAL

.50 R. MIN.
TYPICAL

RIVET TRBLE
SKIN GAGE

RIVET DIA.

.020
.025
.032
.040
.051

1/8
1/8
1/8
1/8
5/32

t "

o
*e
\
-

ATCH
2024-T3 ALCLAD
___

FLUSH PATCH AT
STRINGER/BULKHEAD
INTERSECTION

ORIGINAL PARTS

]

NOTE

REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-4.
19-14

This procedure is not recommended in areas where
stringers are riveted to
bulkheads.

Skin Repair (Sheet 4 of 6)

DOUBLER2024-T4 ALCLAD

0. 5" MIN. RADIUS
TYPICAL

2D MIN.

REPAIR PARTS IN CROSS SECTION

Figure 19-4.

Skin Repair (Sheet 5 of 6)
19-15

SKIN

CLEAN OUT DAMAGED AREA

A-A

PICK UP EXISTING

SKINRIVET-PATTERN

1/4"
v
RADIUS

10 RIVETS
EACH SIDE OF
DAMAGED AREA
FILLER -2024-T4

ALCLAD

.
i0 ,.^

1/4" EDGE MARGIN

DOUBLER
ALCLAD

-MS20470AD4

2024-T4

RIVETS

ORIGINAL PARTS

REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-4.
19-16

Skin Repair (Sheet 6 of 6)

DOUBLER

2024-T4 ALCLAD

1/4" EDGE MARGIN

RIVET SPACING TO MATCH
PATTERN
IN SKIN

STRINGER

6 RIVETS EACH SIDE
OF DAMAGED AREA

CLEAN OUT DAMAGED AREA

FILLER

2024-T4 ALCLAD

A-A

MS20470AD4 RIVETS

SKIN
ORIGINAL PARTS
REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-5.

Stringer and Channel Repair (Sheet 1 of 4)
19-17

2024-T4 ALCLAD

FILLER-

A-A
"G\

MARGIN

STRIP -

2024-T3 ALCLAD

1/4" EDGE MARGIN

lP^

/^^-^

)CLEAN
~

OUT 4
!
L r
\ < >AREA
)DAMAGED

5 RIVETS EACH SIDE
OF DAMAGED AREA

ANGLE -

2024-T4 ALCLAD4"
SPACING

STRINGER
PICK UP EXISTING SKIN RIVETS

MS20470AD4 RIVETSF

ORIGINAL PARTS

]

REPAIR PARTS

REPAIR PARTS IN CROSS SECTION

Figure 19-5.
19-18

Stringer and Channel Repair (Sheet 2 of 4)

-IORIGINAL PARTS
'
*

REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

STOP DRILL CRACK

A-A

];
s!

/'CHANNEL
/

M5204
^emA
\/
Figure

9-5.

Stringer andChneRepair (ShTe

*-~--

-DOUBLER
- 2024-T4 ALCLAD

1/4" EDGE MARGIN

>
Sts s K~ S"
^ ssf~::iN

MS20470AD4
R

2 ROWS OF RIVETS
OUTBOARD OF
LIGHTENING HOLE

IVET S

SPACIh.. e

^>--

SKIN

A
Figure 19-5.

Stringer and Channel Repair (Sheet 3 of 4)
19-19

FILLER -

DOUBLER -

2024-T4 ALCLAD

2024-T3 ALCLAD

-A---A
CLEAN OUT DAMAGED AREA

1/4" RADIUS

2 ROWS RIVETS OUTBOARD
OF LIGHTENING HOLE

---

CHANNEL

3/4" RIVET
.
SPACING
1/4" MARGIN
DOUBLER -

MS20470AD4 RIVETS

2024-T4 ALCLAD

ORIGINAL PARTS
-

REPAIR PARTS
REPAIR IN CROSS SECTION

Figure 19-5.
19-20

Stringer and Channel Repair (Sheet 4 of 4)

STOP DRILL CRACK IF CRACK DOES
NOT EXTEND TO EDGE OF PART

DOUBLER -2024-T3

ALCLAD

EDGE

PARTS
ORIGINAL
IN CROSS SECTION A
PARTS
U REPAIR

--------- RIB

A-A

PARTSORIGINAL
REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-6.

Rib Repair (Sheet 1 of 2)
19-21

FILLER -

2024-T4 ALCLAD

2024-T3 ALCLAD
CLEAN OUT DAMAGED AREA

ONE ROW RIVETS

Figure 19-6.
19-22

Rib Repair (Sheet 2 of 2)

FILLER -2024-T4

2024-T4 ALCLAD

ALCLAD

/~. s~ 1
:_/^

DOUBLER 2024-T3 ALCLAD

..-I

CLEAN OUT DAMAGED AREA

3/8" RADIUS

ANGLE2024-T4 ALCLAD

SPAR

3/8" EDGE MARGIN
(TYPICAL)

MS20470AD4 RIVETS

ORIGINAL PARTS

REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-7.

A-A

Wing Spar Repair (Sheet 1 of 4)
19-23

REPAIR PARTS IN CROSS SECTION

CLEAN OUT DAMAGED AREA
2024-T3 ALCLAD

1/4" EDGE MARGIN (TYP.)

NOTE

Figure 19-7.
19-24

Wing Spar Repair (Sheet 2 of 4)

- FILLER ALCLAD

3/4" RIVET
SPACING

2024-T4

SCLEAN OUT
DAMAGED AREA
1/4" EDGE MARGIN

A-A

ORIGINAL PARTS

REPAIR PARTS

-*j

REPAIR PARTS IN CROSS SECTION
Figure 19-7.

Wing Spar Repair (Sheet 3 of 4)
19-25

FILLER --

2024-T4 ALCLAD

FILLER-2024-T4 ALCLAD

FILLER-2024-T3 ALCLADANGLE -

CLEAN
DAMAGED AREA

ANGLE-

2024-T4 ALCLAD

SPAR

DOUBLER

2024-T3 ALCLAD
STRP
--

EDGESlK MARGIN
-

S2024-TAD4
ALVETS

ORIGINAL PARTS

1MS20470AD4
RIVETS

REPAIR
PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-7.
19-26

Wing Spar Repair (Sheet 4 of 4)

DOUBLER -

2024-T4 ALCLAD

A-A

DAMAGED AREA
-ILLER2024-T4 ALCLAD

ORIGINAL PARTS

REPAIR PARTS
BREPAIR PARTS IN CROSS SECTION

Figure 19-8.

Auxiliary Spar Repair
19-27

NOTES:
1.

Dimple leading edge skin and filler material; countersink the doubler.

Use MS20426AD4 rivets to install doubler.

Use MS20426AD4 rivets to install filler, except where bucking is impossible.
Cherry (blind) rivets where regular rivets cannot be bucked.

Contour must be maintained; after repair has been completed, use epoxy filler as necessary
and sand smooth before painting.

Vertical size is limited by ability to install doubler clear of front spar.

Lateral size is limited to seven inches across ti-nmmed-out-area-

Number of repairs is limited to one in each bay.

Use CR162-4

1" MAXIMUM RIVET
SPACING (TYPICAL)

DOUBLER NEED NOT
BE CUT OUT IF ALL
RIVETS ARE ACCESSIBLE
FOR BUCKING

v5/16"
/

MINIMUM EDGE
MARGIN (TYPICAL)

REPAIR DOUBLER
2024-T3 ALCLAD

.040" THICKNESS

FILLER MATERIAL
FI

ORIGINAL PARTS

2024-T3 ALCLADSAME THICKNESS

AS SKIN

Figure 19-9.
19-28

Leading Edge Repair

LEADING EDGE SKIN

S-1443-1 DOUBLER
NOTE
Parts are available from the
Cessna Service Parts Center.

#40 (.098) HOLE
(10 REQD)

WING SKIN (REF)
5.062
DIA

COVER

S2SS-225-4F

S-1022Z-8-6 SCREWS

MS20426AD3 RIVETS
PRECAUTIONS:
1. Add the minimum number of access holes necessary.
2. Any circular or rectangular access hole which is used with approved optional equipment installations may be added in lieu of the access hole illustrated.
Use landing light installations instead of adding access holes where possible. Do not add access
3.
holes at outboard end of wing; remove wing tip instead.
Do not add an access hole in the same bay where one is already located.
4.
. Locate new access holes near the center of a bay (spanwise).
6.
Locate new access holes forward of the front spar as close to the front spar as practicable.
7.
Locate new access holes aft of the front spar between the first and second stringers aft of the
spar. When installing the doubler, rotate it so the two straight edges are closest to the stringers.
8. Alternate bays, with new access holes staggered forward and aft of the front spar, are preferable.
9. A maximum of five new access holes in each wing is permissible; if more are required, contact
the Cessna Service Department.
10. When a complete leading edge skin is being replaced, the wing should be supported in such a
manner that wing alignment is maintained.
a.

Establish exact location for inspection cover and inscribe centerlines.

Determine position of doubler on ving skin and center over centerlines.
locations and drill to size shown.

Cut out access hole using dimension shown.

Flex doubler and insert through access hole, and rivet in place.

Position cover and secure using screws as shown.

Figure 19-10.

Mark the ten rivet hole

Access Hole Installation
19-29

1/4" EDGE MARGIN

A-A

-- CLEAN OUT DAMAGED AREA

ANGLE -

2024-T4 ALCLAD

10 RIVETS EACH SIDE
OF DAMAGED AREA

.. - f
FILLER -

FIREWALL ANGLE

2024-T4 ALCLAD

0
'^

'YP //'

MS20470AD4 RIVETS

-FIREWALL

--------

ORIGINAL PARTS
REPAIR PARTS
REPAIR PARTS IN CROSS SECTION

Figure 19-11.
19-30

Firewall Angle Repair

FUSELAGE SKIN

SECTION 20
PAINTING

NOTE
This section is divided into two parts. Part 1 covers the procedures
used, at the factory, for over-all painting of the aircraft. Part 2
covers the procedures for touch-up painting on the aircraft. Before
attempting any painting on the aircraft, determine the type and color
of the paint that is on the aircraft. The color and type of paint, on
the aircraft when it left the factory, is stamped in code of the Finish
and Trim Plate located on the left front door post. Applying this code
to the applicable Parts Catalog the type and color can be determined.
In all cases determine the type of paint that is on the aircraft before
adding touch-paint as some types of paint are not compatible.
PART 1
OVER-ALL PAINTING
20-1.

PAINTING.

20-2. Painting an aircraft requires little special
equipment. The average shop will have the compressor, spray gun, and clean place to work required
for a good paint job. Ordinarily, painting involves
four basic steps. They are:
1. Stripping - Removing of paint to the bare
metal.
2. Cleaning - Washing down the aircraft
thoroughly to remove all oil, grease, and dirt.
3. Priming - Applying one priming coat before
painting with acrylic paint.
4. Painting - Applying coat of final paint, then
adding decorative strips and identification markings.
20-3. MATERAILS. The following list of materials
is for use in both Part 1 and Part 2. These materials can be obtained from the Cessna Service Parts
Center.
a. Thinner T-6094A
b. Thinner T-8402A
c. Thinner T-7945
d. Thinner T-9275
e. Thinner T-7987
f. Thinner T-9186
g. Solvent No. 2
h. Class A Solvent Proof Paper
i. Wash Primer EX2016G
j. Activator EX2016A
k. Primer Surfacer EX8229B
1. Sealer EX8229A
m. Acrylic Paint PX114A-Series
n. Filler White Streak
o. Filler Green Stuff No. 74
p. Wiping Cloth
q. Polishing Compound No. 606
r. Wax and Grease Remover DX440
s. Klad Polish
t. Imperial Cleaner
u. Tape, Permacel No. 781
v. Thinner T-1411

20-4. CLEANING.
a. Inspect aircraft for any surface defects, such as
small dents or unsatisfactory previous repairs. Refer to Part 2 for repairs.
b. Wipe excess sealer from around windows and
skin laps.
c. Mask windows and any other areas not to be
primed, with Class A Solvent Proof Paper and Permacel tape no. 781.
d. Use Klad Polish to remove stains, oxides, etc.,
from bare aluminum.
e. Use T-6095A for final cleaning of the aircraft
prior to applying primer. Saturate a contaminantfree, lint free cloth in T-6094A thinner and wring
out so no thinner is dripping from the cloth. Wipe
the aircraft surface using the thinner saturated cloth
and immediately following sipe surface with a dry,
lint free cloth.
NOTE
It is important that the thinner is wiped before it evaporates. Change cloths often, so
that aircraft surface is thoroughly cleaned
and the surface is not contaminated from the
use of a dirty cloth. Always use clean thinner in the final cleaning. Be sure that thinner is disposed of when contaminated.
20-5.

PRIMER PREPARATION.
NOTE

Mix EX2016G primer only in quantities required for use within six hours and then only
in a stainless steel container. Mixed primer
shall be discarded if not used within six hours.
a. Mix EX2016G primer and EX2016A activator in
a 1:1 ratio and stir thoroughly.

20-1

NOTE
The mixed primer shall stand a minimum of
30 minutes prior to being applied to the aircraft.
b. Check all tapes to make sure that they are adhered to paper and masked surface. Cover flap
tracks, nose gear strut tube, wheels, and shimmy
dampener rod ends.
c. Blow all contaminates from surface of aircraft
with a jet of dry compressed air.
20-6.

PRIMER APPLICATION.

d. Burn down with T-8402A where necessary as
soon after application of paint as practicable. Burn
down should be held to a minimum.
e. Allow the finish to flash off for 10 minutes and
move airplane to force dry oven and dry for 1-1/2
hours at 120 to 140 degrees Fahrenheit.
f. Remove airplane from oven and allow airplane
to cool to room temperature.
20-9. PREPARATION FOR STRIPES. (ACRYLIC
COLORS.)
a. Mask stripe area using Permacel No. 781 tape
and class A solvent proof paper. Double tape all
skin laps to prevent blow by.

NOTE
Air pressure at gun shall be between 40 to
50 psig. At all times, keep gun six to eight
inches from the work and perpendicular to
surface being primed. DO NOT PAINT WITH
ARCING MOTION. Keep paint room at 75 to
85 degrees Fahrenheit.
a. Apply EX2016G primer in one well broken up
wet, even coat to 0.0003 to 0. 0005 inch dry film
thickness.
b. Allow primer to dry until a firm pressure with
the finger nail will not penetrate the coating.
NOTE
Primer shall be top coated within four hours
of application.
20-7. PAINT PREPARATION (ACRYLIC WHITE).
a. Thoroughly stir and mix in original container to
make sure all pigments are in solution.
b. Mix required amount of acrylic white with T8204A thinner. Recommended thinning ratio is 100
parts paint to 100-120 parts thinner by volume. This
variation in thinning may be required to facilitate
application during hot weather and is permitted.
c. Scuff sand the primer only where runs or large
dirt particles are in evidence. (Over-all sanding
operation will be performed after application of the
first coat of paint. )
20-8.

PAINT APPLICATION (ACRYLIC WHITE).
NOTE

Air pressure at the gun should be 40 to 50 psig
and 12±1 psig at the pot during application. At
all times, keep gun six to eight inches from the
work and perpendicular to surfaces being painted. DO NOT PAINT WITH ARCING MOTION.
a. Apply one light wet even coat of paint to the aircraft.
b. Let dry until not tacky and lightly sand with No.
400 paper and wipe with a tack cloth.
c. Apply second coat even and wet. The minimum
thickness necessary to provide good hiding is recommended. Heavy coats, applied in an attempt to improve gloss, should definitely not be applied or the
acrylic may craze.
20-2

NOTE
If an unpainted airplane is to receive stripes
only, clean and prime as outlined in paragraphs
20-4 through 20-6.
b. Scuff sand stripe area with No. 400 or No. 600
sandpaper. The use of power sanders should be held
to a minimum with care exercised to preclude sanding through the white base coat.
c. Wipe sanded surface with a tack cloth and check
all tapes to be sure they are adhered to surface.
20-10. PAINT PREPARATION (ACRYLIC COLOR).
a. Thoroughly stir and mix in original container to
make sure all pigments are in solution.
b. Mix required amount of stripe color with T-7945
thinner. Recommended thinning ratio is 100 parts
paint to 100-125 parts thinner by volume. This will
allow for the slight thinner variation required with
different colors.
20-11.

APPLICATION OF STRIPES.
NOTE

Air pressure at the gun shall be 40 to 50 psig.
At all times keep gun six to eight inches from
the work and perpendicular to the surface being
painted. DO NOT PAINT WITH ARCING MOTION.
a. Keep first coat even and light. The first coat
should be somewhat lighter than the second to avoid
sags, but should be wet enough to achieve a smooth
surface.
b. Apply second coat in wet passes to achieve full
coverage. Heavy coats applied in an attempt to improve gloss, should definitely not be applied or the
acrylic may craze.
c. Inspect for overspray and apply burn down agent,
T-7945 thinner, to any area showing overspray.
Care in application will minimize overspray.
NOTE
Burn down of non-metallic colors shall be
accomplished with T-7945 thinner. Burn
down of metallic colors shall be accomplished with T-7987 thinner.

d. The masking tape and paper shall not be removed
until the paint has dried a minimum of 15 minutes.
Care shall be used in removal of masking to prevent
damage to the finish.
20-12. PROCEDURE FOR PAINTING WITH CESSNA
LACQUER - 27H SERIES.
20-13. PREPARATION. Thoroughly clean all surfaces and beyond area to be painted, with T-6094
thinner. Extreme care should be taken to remove
all letters, grease, bugs, etc. Carefully mask off
stripe areas to be painted and see that all tapes are
firmly adhered to metal to prevent ragged edges.
Class "A" wrapping paper and thinner-proof tape
should be used to cover windows and windshield.
This will prevent damage from solvent and thinner
vapors. Newspapers will not provide adequate protection.
20-14.

PRIMER - MIXTURE AND APPLICATION.
NOTE

Mix EX-2016 primer only in quantities required for use within six hours and then only
in stainless steel bucket.
a. Mix EX-2016 primer and T-6070 activator in a
1:1 ratio and stir thoroughly.

b. Check carefully before second and third coats
for defects and correct before final coats.
c. Using T-6094 thinner as a "burn-down" agent,
"burn-down" to give smooth, even surfaces free
from overspray.
20-17. PROCEDURE FOR PAINTING WITH CESSNA
ENAMEL VINYL - 82 SERIES.
NOTE
82A, 82B, and 82 are interchangeable, although 82A and 82B have better flow characteristics.
20-18. PREPARATION. Thoroughly clean all surfaces and seans with T-6094 thinner. Extreme care
should be taken to assure that no oil seepage occurs
from seams, splices, or rivet heads. All bugs and
foreign matter should be removed from the airplane
before painting. Thoroughly inspect after cleaning to
be sure all surfaces are ready for priming. Class
"A" wrapping paper and thinner-proof masking tape
should be used to cover windows and windshield.
This will prevent damage from solvent and thinner
vapors. Newspapers will not provide adequate protection.
20-19.

PRIMER - MIXTURE AND APPLICATION.
NOTE

NOTE
The primer shall stand after mixing a minimum of 30 minutes prior to being applied to
the airplane.
b. Apply EX-2016 in a well broken up, wet, even
coat.
c. Mix one part EX-2414 yellow lacquer primer
with two parts T-6094 thinner.
d. Apply one well broken up, wet, even coat of the
EX-2414 primer over the EX-2016 primer,
20-15. PREPARATION OF LACQUER COLORS - 27H
SERIES.
a. Thoroughly stir and mix in original container to
make sure all pigments are in solution.
b. Thin required amount of lacquer color with
T-6094 thinner in a 1:1 ratio. Mix thoroughly and
strain into cups before using.
20-16. APPLICATION OF LACQUER COLORS - 27H
SERIES.
NOTE
Air pressure
At all times,
the work and
painted. DO
TION. Keep
Fahrenheit.

at gun should not exceed 40 psig.
keep gun six to eight inches from
perpendicular to surface being
NOT PAINT WITH ARCING MOpaint room at 75 to 85 degrees

a. Apply first coat even and wet; second and third
coats in the same manner.

Mix EX-2016 primer only in quantities required for use within six hours and then only
in stainless steel bucket.
a. Mix EX-2016 primer and T-6070 activator in a
1:1 ratio and stir thoroughly.
NOTE
The primer shall stand after mixing a minimum of 30 minutes prior to being applied to
the airplane.
b. Apply EX-2016 primer in a well broken up, wet,
even coat. If primer has to be sanded, dry scuff sand
with #600 paper and reprime. Sanding breaks film,
result in poor adhesion.
NOTE
On all leading edge surfaces, apply a cross
coat, wet and even, of EX-2016 primer.
c. Clean equipment immediately after use and under
no consideration use EX-2016 primer that has been
mixed longer than six hours.
20-20. PREPARATION OF ENAMEL VINYL COLORS
- 82 SERIES.
a. Thoroughly mix and stir in original container
to make sure all pigments are in solution.
b. Thin required amount of vinyl color with T-1866
vinyl thinner in a 1:1 ratio. Mix thoroughly and
strain into either a cup or pressure pot.
20-3

20-24. MIXING PROCEDURE: All paint shall be
thinned to spraying consistency as follows:
a. Hi-Visibility paint shall be thinned with two
parts Toluene thinner to three parts paint.
b. Clear top coat shall be thinned with one part
Xylene thinner to one part paint.
c. White base coat shall be thinned with one part
thinner to one part paint. This formula applies to
either lacquer or vinyl.

20-21. APPLICATION OF VINYL COLORS - 82
SERIES.
NOTE
If vinyl is to be applied from a pressure pot,
do so under the following conditions: Pressure of 10 psig. Regulate gun pressure at gun
with test gauge to 25 psig, using gun with FX
needle and fluid tip, with fan set wide open
and yield two turns open. If cups are used,
set fun at 30 psig with EX needle and fluid tips,
fan set one turn open and yield wide open.

NOTE

a. Apply first coat even and wet; second and third
coats in same manner.
b. Check second and third coats, mask off and
lightly wet sand with #400 paper the painted surfaces
of previous color that is in area to be painted.
NOTE
On all leading edges apply a fourth coat. After
finishing each color coat, "burn-down" with
T-1411 thinner as the "burn-down" agent. Remove all masking from painted surfaces after
each color application. If you have a Heat
Room, turn up the heat and dry paint at temperatures of 125 to 145 degrees Fahrenheit,
for at least three hours. Heat will give a
very good reflow on vinyl paint.

20-25. SURFACE PREPARATION. Hi-visibility
paint must be applied over a good white undercoat.
The preferred white undercoat is white lacquer. If,
however, the airplane is already painted with vinyl
base paint, the white undercoat may consist of white
vinyl. A white primer may also be used as the
undercoat.
20-26. APPLICATION.
a. Apply three well broken up, even coats of white
undercoat. Allow sufficient drying time. Wipe with
tack rag.
b. Apply one heavy wet coat of Hi-Visibility paint.
This coat should consists of three wet passes over the
entire area. Allow two or three minutes drying time
between passes. Dry coat should be 2.5 to 3.5 mils
thick. Allow one to two hours drying time.
c. Wipe surface with tack rag to remove overspray.
d. Apply two wet coats of clear top coat, consisting
of two passes per coat. Dry coat should be 1.5 to
2.5 mils thick.

20-22. PROCEDURE FOR APPLICATION OF HIVISIBILITY PAINT.
20-23.

Either Toluene or Xylene may be used as the
thinner for Hi-Visibility paint and the top coat.
Tolueme is recommended for the Hi-Visibility
paint and Xylene for the top coat.

MATERIALS REQUIRED are:

3 qts Switzer Orange Day-Glo

NOTE

2 qts Toluene Thinner

Hi-Visibility paint is not offered at the
factory.

2 qts Switzer Filteray, Type B Top Coat
2 qts White Base Coat
2 qts Thinner
PART 2

TOUCH-UP PAINTING

20-27.

TOUCH-UP-GENERAL.

20-28. Where necessary to touch-up or refinish an
area, the edge of the finish adjacent to the defect
shall be feathered by sanding with No. 320 paper and
followed with No. 400 paper. Avoid, if possible,
sanding through the primer. If the primer is penetrated over an area 1/2 inch or larger, repriming is
necessary. Avoid spraying metal primer on the adjacent paint as much as possible.
a. When touching up acrylic, vinyl, or lacquer, use
EX2016G primer mixed one part primer to one part
EX2016A activator. Stir thoroughly and allow to set
30 minutes before spraying.
b. When touching up epoxy, use Dupont 818-012
20-4

primer mixed two parts primer to one part 8539
activator. Stir thoroughly and allow to set 30 minutes before spraying.

Before attempting touch-up, determine the
type of paint that is on the aircraft. Some
types of paints are not compatible. Acrylic
paint does not adhere to vinyl paint satisfactorily. Therefore, when acrylic paint is
to be applied over vinyl paint, a barrier coat
of lacquer paint is required between the vinyl
and acrylic paint.

20-29. TOUCH-UP-ACRYLIC,
a. Fill the feathered areas by spraying on several
light coats of EX8229A Surfacer. Only sufficient
Surfacer should be used to assure filling. Allow 5 to
8 minutes drying time between coats of Surfacer
used. Sand the Surfacer smooth with No. 400 paper.
Apply a light coat of EX8229A Sealer over the sanded
Surfacer. After drying for 5 to 8 minutes, spray the
Acrylic top coat.
NOTE
Dry overspray may be removed by burndown
with T-8402A (White), T-7945 (non-metallic
color), T-7987 (metallic color), or by compounding with Dupont No. 808 Rubbing Compound.
20-30. TOUCH-UP-VINYL.
a. If priming with EX2016G primer is required, a
light coat of MIL-P-8585 Zinc Chromate primer
thinned four parts Toluol to one part primer shall be
applied over the EX2016G primer.
b. Fill the feathered areas by spraying on several
light coats of ACME 538 Dark Grey Surfacer. Allow
5 to 8 minutes drying time for each coat of Surfacer.
Sand the area smooth with No. 400 paper and apply
the top coat of vinyl.
NOTE
Dry overspray may be removed by burndown
with T-1411, or by compounding with Dupont
808 Rubbing Compound.
20-31. TOUCH-UP-LACQUER.,
a. When priming with EX2016G is required, a light
coat of EX2414 primer shall be sprayed over the
EX2016G primer. Mix one part EX2414 Yellow lacquer primer with two parts T-6094 thinner. Fill the

feathered areas by spraying on several light coats of
ACME 538 Dark Grey Surfacer. Allow 5 to 8 minutes dry time for each coat of Surfacer applied. Sand
the area smooth with No. 400 paper and apply top
coat of lacquer.
NOTE
Dry overspray may be removed by burndown
with T-6094 thinner, or by compounding with
Dupont No. 808 Rubbing Compound.
20-32. TOUCH-UP-EPOXY.
a. If bare metal is not exposed, or after the metal
is primed, spray a light coat of Dupont Epoxy Primer
over the rework area. Mix two parts 825-8500
Primer with one part VG5943 activator. If a thinner
is required, use T-3871 thinner. Stir primer and
allow to set 45 minutes before spraying.
NOTE
Top coat must be applied over primer within
72 hours of priming.
b. When the primer is DRY, apply top coat, Cessna
Part Number CES1054-826. The Dupont Chemical
Resistance Enamel white epoxy base coat shall be
mixed one part enamel to one part VG8339 activator.
If thinning is required, use T-3871 thinner.
c. The Enmar 5400 series color epoxy is used to
paint the stripes. All colors, except the Valor Red,
shall be mixed one part by volume paint to one part
by volume T-5400 Adduct Thinner. Mix the Valor
Red in the same ratios, except use T-6487 Adduct
Activator. If a thinner is required, use T-5402
Thinner. Stir thoroughly and allow the mixed paint
to set for 30 minutes prior to spraying.

20-5/20-6

APPENDIX

ELECTRICAL WIRING DIAGRAMS

Table of Contents
Model Number

Drawing Number

150 & F150

0410011

172, P172, F172, FP172 & FR172E

0500062

180 & 185

0700092

182

0770610

NOTE
The page numbering method in this Section differs from that
of the rest of the book.

However, each model series drawing

number begins with an index of diagrams contained therein,
which will facilitate locating any particular diagram.

Al-1

Cessna.
WIRING
DIAGRAM
MODEL

150

DWG. NO.

0410011

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

TABLE OF CONTENTS

1.0

Title Page

2.0
2. 1
2.2

Table of Contents
Table of Contents
Table of Contents

3.0

Notes

10-4-62

4.0
4. 1
4.2
4. 3
4.4
4.5
4.6
4.7
4. 8
4.9

10-4-62

4. 10

DC Power
Not Used
Generator & Warning Light
Ammeter (Opt.)
Wiring Diagram - Fuse & Bus Bar Wiring
Not Used
Not Used
Wiring Diagram - Alternator 60 AMP
Wiring Diagram - Ammeter 60 AMP
Wiring Diagram-Circuit Breaker, Fuse & Bus Bar
Wiring
Wiring Diagram - Alternator System, 60 AMP

5.0
5. 1
5.2

6.0
6.1
6.2
6.3

2-15-68
2-15-68
2-15-68

11-3-65
11-3-65
11-3-65

D-Inac.
D-Inac.
A-Inac.

7-8-66
8-10-66

A-Inac.
A

11-4-66
12-20-67

B
B-Inac.

Ignition
Magneto
Wiring Diagram - Magnetos

10-4-62
11-3-65
12-20-67

D-Inac.
NC-Ina

Engine Control
Contactor and Starter
Contactor & Starter
Wiring Diagram - Contactor & Starter

10-4-62
5-11-65
11-3-65
1-9-68

D-Inac.
B-Inac.
A

Ctssna.
DATE:

REV

DATE ISSUED

TITLE

PAGE NO.

TITLE:
|

2-15-68

DRAWING NO.

WIRING DIAGRAM---

MODEL

150

0410011
PAGE:

2.0

CESSNA AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

TABLE OF CONTENTS
REV

7.0

Not Used

8.0
8.1
8.1.1
8.1.2
8.2

Engine Instruments
Fuel Indicator & Transmitter
Fuel Ind. & XMTR
Wiring Diagram - Fuel Ind. & XMTR
Hourmeter (Opt.)

10-4-62
4-6-65
11-3-65
12-20-67
9-29-66

9.0
9. 1
9.2
9.3
9.4
9.5

Flight Instruments
Not Used
Turn & Bank
Pictorial Gyro (Opt.)
Turn Co-Ordinator
Brittain Wing Leveler (Opt.)

10-4-62
12-20-67
7-8-63
12-20-67
12-20-67

D-Inac.
A
A
A

10.0
10. 1

Other Instruments
Clock

10-16-62
11-3-65

11.0
11.1
11.1.1
11.1. 2
11.1.3
11. 2
11.2.1
11.2.2
11.2.3
11.3
11.3.1
11.3.2
11.4
11.4.1
11.4.2

Lighting
Courtesy Lights
Courtesy Lights (Opt.)
Wiring Diagram-Courtesy Lights (Opt.)
Wiring Diagram-Courtesy Lights
Instrument Lights
Instrument Lights
Wiring Diagram - Instrument Lights
Wiring Diagram - Instrument Lights
Landing & Taxi Lights
Landing & Taxi Lights (Opt.)
Landing & Taxi Lights (Opt.)
Navigation Lights
Navigation Lights
Navigation Lights

10-4-62
4-6-65
11-3-65
12-20-67
1-9-68
4-6-65
11-3-65
6-7-67
12-20-67
4-6-65
11-3-65
12-20-67
4-6-65
11-3-65
12-20-67

B-Inac.
A-Inac.
A-Inac.
NC
B-Inac.
A-Inac.
NC -Ina
NC-Ina
B-Inac.
NC-Ina
A
C-Inac.
A-Inac.
B

TITLE:

Cssnaa.
o

DATE ISSUED

TITLE

PAGE NO.

DATE:

2-15-68

B-Inac.
B-Inac.
B
NC

WIRING DIAGRAM---

DRAWING NO.

MODEL

04011
0410011

150
PAGE:

2. 1

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

TABLE OF CONTENTS
PAGE NO.

TITLE

11.5
11.6

Rotating Beacon (Opt.)
Light - Flashing Beacon (Opt.)

12.0

Not Used

13.0
13. 1
13.2
13.2.1
13. 3

DATE ISSUED

REV

11-3-65
12-20-60

C-Inac.
B

Heating, Venting & De-Icing
Cigar Lighter (Opt.)
Pitot & Stall Warning Heat (Opt.)
Pitot Heat (Opt.)
Wiring Diagram - Pitot Heat (Opt.)

10-4-62
8-10-66
5-3-65
11-3-65
12-20-67

D
NC-Ina
NC-Ina
A

14.0
14. 2
14.2.1
14. 2.4

Control Surface Section
Wing Flaps - Electric
Wing Flaps - Electric
Wing Flaps - Electric

9-6-63
10-20-65
8-17-67
12-20-67

A-Inac.
B-Inac.
A

15.0
15. 1

Warning & Emergency Section
Stall Warning

10-4-62
5-3-65

B-Inac.

E9ssnla.
DATE:

TITLE:

2-15-68

WIRING DIAGRAM---

MODEL

DRAWING NO.

150
PAGE:

2. 2

0410011
04

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

NOTES

2. WIRE CODE
3.

PER CES 1100.

WIRE CODE DESIGNATIONS
"S"

SUFFIX

APPLICATION

AND WIRE LENGTH TOLERANCES

ON WIRE GAUGE IN WIRE TABLE DENOTES

PER CES 1015.

SHIELDED

WIRE.

4. NON-SHIELDED WIRES TO BE PER MIL-W-5086, TYPE I (Pvc), NYLON JACKET.
5. SHIELDED WIRES TO BE PER MIL-C-7078, TYPE II WITH MIL-W-5086 TYPE I CONDUCTOR
6. "DS" SUFFIX ON WIRE GAUGE IN WIRE TABLE DEBMTES DOUBLE SHIELDED WIRE.
7. ALL WIRS TO BE PREFIXED A-XXX.
8. WHEN "(OPT)" IS USED IN THE TITLE BLOCK OF A DIAGRAM, ALL WIRES SHOWN THEREIN
ARE OPTIONAL EXCEPT WHERE NOTED AS "(STD)".
SPECIFI1 AS "(OPT)" ARE TO BE INSALLED AS STANDARD EQUIPMENT.
9. ALL WIRE
THE AIRPLANE ASSEMBLY WILL SPECIFY THE ADDITIONAL EQUIPMENT REQUIRED FOR DELUXE
VERSIONS.

Cessna.
DRAWING NO.

WIRING DIAGRAM---

9_DRAWN;TITLE:

MODEL

150

0410011
REV.

CESSNA AIRCRAFT

PAGE:

3.0

CO.. COMMERCIAL AIRCRAFT DIV.. WICHITA. KANS.

D. C. POWER
SECTION

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,

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(OPT

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Csi.

I"::'"

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eTE5C02
S0olV3

TABLE

WIRING DIAGRAM-

_____ _____*

____

12
10

^WIRE

=
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IO4

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{04r\00\
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Cesa.

WIRING DIAGRAMAMMETER Cessna.
<

ENGINE COMPARtMENT

-- .11

- -

(14

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o

A.-PB(

IGNITION
SECTION

Cessna.
~DRAWING
-,»
----

....

ORAWN

150

APO

°o

04i011
EPAGE:

CESSNA

NO.

TITLE: WIRING DIAGRAM---

MODEL

DATE

*--«..._~

AIRCRAFT CO.,

COMMERCIAL

AIRCRAFT

5 0

DIV.,

WICHITA.

KANS.

WIRE TABLE

,----

-UIPMENT TALE

ENGINE CONTROL
SECTION

):14NUUme~CTERU~(*
'I-TOboEl

|IGI
e.,t.0
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5
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7y,,4

EQl0UIPIMENT TWABLE

,S 4

'I.;

ENGINE INSTRUMENTS
SECTION

Cessna.
DRAWING

NO.

*
BT REV; FUEL 1ND UoL LE
L V»
. , o .T' A ,C
I
OAE. LT;

_______ '

I~~n~~~~r*~

-,/- l'/kq

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Th^K. X'TR.

LEFT FUEL.
TAUK XMTQ.

LEFr FUl5

4eqio I

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C010
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EQUIPMENT

,
...
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A
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TABLE

*<1i

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68_,SWIRE

t5 FUEL

TABLE*IS-1__

liD.4 XMT.

SR-SU

P.6 I

I'«_____
_

DIAGRAM-

'WIRING
,.,,

_____

Cena.

0ce

150

OIL

HOUETE

PRESSURE
SWITCH

[-O-DF

SS-

l--

(SR 5033;

DF4

DFI
DF2

oBAT~k--.O---~~

°O-ATIL

OCSRCLOCK
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DCS;(REF)-*-rDC2E),*>->DC3(,Ef).

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ODC4(REF)

NOTE:
>. WIRIUC, OIACRAM SHOWW IS FOR USE
rVHEU AUL OPTIOUAL ELECTRIL CLOCK
IS IIUTALLED. WHEW ELECTRC. CLOCK
15 MOT IUSTALLEO WIZEA-DFI
SWITCh TO__
COWuECTS PRECSSUR
FUSE
LUSTALL S-lOqlruSEHOLOER
- FUSEHOLDE.
oV90
S.
PD s-

__
_

________

1367-1
Sl493-1
5s1367-l ____________93-1
5s-6i-

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DF3
D0F21 !F

DF I It

__ WIRE TABLE_....

G_____.__

_
4

Sl13137N1

0
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'6645i01-IOi

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CLOCK
HOURETER_ ~_

OIL PR SSURE sw.

EQUIPMENt TABLE

DIAGRAM.!.WIRING

HOURMETER

(PT)

I *rAT CCNTACT,
ottflP'C

367-16 SOLDE

0410011

.or.~~LIo a.

................

...........

FLIGHT INSTRUMENTS
SECTION

Cssna.
DRAWING NO.
T

DRAWN
DATE

-/z

TITLE: WIRING DIAGRAM---

MODEL

150

o4ioo0i

REtVISIONS

OTHER INSTRUMENTS
SECTION

Cessna.
DRAWING NO.
DRAWN

IS,

TITLE: WIRING DIAGRAM---

|VISION

- BATTERY

PAZ

CLOCAK(

AIl 0

LIGHTING
SECTION

Cessna.
DRAWING NO.

TITLE: WIRING DIAGRAM---

DRAWN

MODEL

DATE

150

0410011
REV

CESSNA AIRCRAFT CO.. COMMERCIAL

11.0

AIRCRAFT DIV., WICHITA. KANS.

qOLCtI

39lJI j

_50b

TA_

coo
5.
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I _50 .. ,.;

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~~~~~~NOTE~~~~~S'.~f-I LET
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TERMIMAJLS

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RE«V.«.OMVISION
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WHUW OPT GqUIPM1mT IS NOT %NT^LLEO.

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__________

051419-6
0611t481-6

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EQUIPM~ENT TABLE
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0410011F
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Cessna.
___
_______

FI5

,,,o.n

.- c
.. . oi=l

CONTROL SURFACE
SECTION

DRAWING NO.
DRAWN

DATE

TITLE: WIRING

MODEL

DIAGRAM--150

CESSNA AIRCRAFT CO., COMMERCIAL

0410011

AIRCRAFT DIV., WICHITA, KANS.

WARNING
AND EMERGENCY
SECTION

Cessna
DRAWING NO.
DRAWN

DATE
APPD

TITLE: WIRING

MODEL

DIAGRAM---

150
REV

CESSNA AIRCRAFT CO.. COMMERCIAL

"B"

AIRCRAFT

PAGE:

15.0

DIV.. WICHITA, KANS.

Cessna.
WIRING
DIAGRAM
MODEL

172 - P172 - F172

DWG. NO.

0500062

!C CESSNA
h~~~~~~~~~~

AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.
i

TABLE OF CONTENTS
DATE ISSUED

TITLE

PAGE NO.

REV

1.0

Title Page

2.0
2.1
2. 2

Table of Contents
Table of Contents
Table of Contents

1-31-68
1-31-68
1-19-68

3.0

Notes

4-26-62

4.0
4. 1
4. 1. 2
4. 1. 3
4.2
4.3
4. 3. 1
4.4
4.4. 1
4.4.2
4.5
4.6
4.7
4.8
4.9
4. 11
4. 12
4. 13
4.14

D.C. Power
Battery Circuit
Battery Circuit
Wiring Diagram - Battery Circuit
Regulator, Generator & Warning Light
Ammeter (Opt.)
Starter & Ammeter
Ground Service Receptacle
Ground Service Receptacle (Opt.)
Ground Service Receptacle
Circuit Breaker Wiring
Not Used
Alternator System - 60 AMP (Opt.)
Circuit Breaker Wiring
Wiring Diagram - Alternator System - 60 AMP (Opt.)
Wiring Diagram - Alternator System - 60 AMP (Opt.)
Wiring Diagram - Circuit Breaker Wiring
Not Used
W.D. Alternator System 60 AMP

5-27-63
5-3-66
1--19-68
7-19-68
7-26-66
7-8-66
9-23-67
5-3-66
1-31-67
9-30-67
12-20-65

H
B
A
F-Ina
E-Ina.
D
E-Ina
A
B
A-Ina.

7-8-66
1-31-68
9-23-67
1-19-68
1-31-68

B-Inac
D
C
A
B

9-30-67

5.0
5.1

Ignition
Magneto System

9-26-62
1-19-68

D
M

6.0
6.1
6.1.1

Engine Control
Starter
Starter & Mag 172-P172

9-26-62
5-27-63
8-8-66

E
F-Ina

7.0
7.1
7.2

Fuel & Oil
Fuel Pump
Wiring Diagram - Fuel Pump

5-27-63
8-17-67
1-19-68

A
B

TITLE:

Cessna
DATE:

2-15-68

DRAWING NO.

WIRING DIAGRAM--MODEL
172, P172
PAGE:

0500062
2.0

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA. KANS.

TABLE OF CONTENTS
PAGE NO.

TITLE

DATE ISSUED

REV

8.0
8. 1
8.1.1
8.1.2
8.2
8.2.1
8.3

Engine Instruments
Fuel Gauge & Transmitter
W. D. - Fuel Gage & Transmitter
Wiring Diagram - Fuel Gage & Transmitter
Carburetor Air Temp. Gauge
Carburetor Air Temp. Gauge
Hourmeter (Opt.)

9-26-65
12-20-65
12-20-65
1-19-68
9-23-67
5-29-63
9-29-66

E-Ina
NC
B
G
D-Ina
NC

9.0
9.1
9. 2
9.3
9.4

Flight Instruments
Turn & Bank
Optimum Flight Instruments (Opt)
Turn Coordinator
Wiring Diagram - Turn & Bank Indicator

9-26-62
5-29-63
8-17-67
9-30-67
9-30-67

E
F
B
A

10.0
10.1
10.2

Other Instruments
Clock
Clock

10-16-62
2-3-65
9-30-67

F
B

11.0
11.1
11.1.1
11. 1.2
11.2
11.2.1
11.2.2
11.3
11.4
11.5
11.6
11.7
11.8
11.9
11.10
11.11

Lighting
Dome, Courtesy, & Map (Opt.)
Map & Auxiliary Instrument Light
Dome & Courtesy Lights
Compass & Instruments Lts.
W.D. Compass & Instrument Lights
Wiring Diagram - Compass & Instrument Lights
Landing & Taxi Lts.
Wing & Tail Lts.
Rotating Beacon (Opt.)
Flasher Unit (Opt.)
Dome & Courtesy Lights
W. D. Landing & Taxi Lights (Opt.)
W. D. Wing & Tail Lights
Light - Flashing Beacon (Opt.)
W.D. - Map Light, Control Wheel

9-26-62
1-17-64
8-17-67
12-20-65
6-21-65
9-23-67
1-31-68
12-20-65
12-20-65
12-20-65
12-20-65
9-30-67
9-30-67
1-19-68
11-14-67
9-22-67

D
E-Ina
C
NC-In
F-Ina
B
B
E-Ina
F-Ina
E-Ina
E-Ina
C
C
E
D
A

12.0

Not Used

13.0
13.1
13.2

Heating, Venting & De-Icing
Cigar Lighter
Pitot & Stall Warning Heat

9-26-62
1-19-68
12-20-65

D
K
E-Inac

13.3

W. D. - Pitot Heat (Opt.)

9-30-67

TITLE:

cessna
DATE:

WIRING DIAGRAM--MODEL 172. P172
2-15-68

LPACE:

DRAWING NO.

0500062
2. 1

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

TABLE OF CONTENTS
PAGE NO.

14.0
14.1
14. 2
14. 3
14.4
14.4.1
14.4. 2
14. 5
-14.-6
14. 7

TITLE

DATE ISSUED

REV

Control Surface Section
Not Used
Not Used
Not Used
Wing Flaps
Wing Flaps-Electric & Flap Position Indicator
Wing Flaps - Electric & Flap Position Indicator
Wing Flaps Electric & Flap Position Indicator
Wing_FlapsElectric & Flap Position Indicator
Wing Flaps Electric & Flap Position Indicator

6-2-65
10-20-65
12-20-65
8-22-67
1-19-68
9-30-67

Inac.
A-Ina(.
NC- Iiac.
B-Ina
C
B

15.0
15. 1

Warning & Emergency
Stall Warning Horn & XMTR.

9-26-62
12-20-65

D
E-Ina.

16.0
16. 1

Miscellaneous Section
Power Seats Pilot & Co-Pilot (Opt.)

9-27-63
12-17-63

TITLE:

.
DATE:

2-15-68

WIRING DIAGRAM--MODEL 172, P172
PAGE:

5-27-63

DRAWING NO.
0500062
2. 2

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

NOTES
1.
WIRE CODE DESIGNATIONS

PER CES 1100.

2. WIRE CODE APPLICATION AND WIRE LENGTH TOLERANCES PER CES 1015.
3. "S" SUFFIX ON WIRE GAUGE IN WIRE TABLE DENOTES SHIELDED WIRE.
4. NON-SHIELDED WIRES TO BE PER ML-W-5086, TYPE I (PVC), NYLDN JACKET.
5. SHIELDED WIRES TO BE PER MIL-C-7078, TYPE II WITH MIL-W-5086 TYPE I CONDUCTOR.
6. "DS" SUFFIX ON WIRE GAUGE IN WIRE TABLE DENOTES DOUBLE SHIELDED WIRE.
7. WHEN "(OPT)" IS USED IN TITLE BIDCK OF A DIA., ALL WIRES SHOWN THEREIN ARE
OPTIONAL EXCEPT WHERE NOTED AS "STD."
8. ALL WIRES NOT SPECIFIED AS "(OPT)" ARE TO BE INSTALTED AS STANDARD EQUIPMENT.
THE AIRPIABE ASSEBLY WILL SPECIFY THE ADDITIONAL EQUIPMENT REUIRED FOR DELUXE
VERSIONS.

Cessna.
DRAWING NO.

TITLE: WIRING DIAGRAM--MODEL
172-P172

DRAWN

DATE
APPID

REV:

0500062
"D"

PAGE:

3.0

CESSNA AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV.. WICHITA. KANS.

D. C. POWER
SECTION

Cessna.
DRAWING NO.

TITLE: WIRING DIAGRAM---

DRAWN
.

DATE

APP'D

MODEL

172-P172

0500062
1 REV:

CESSNA AIRCRAFT CO., COMMERCIAL

"D"

PAGE:

AIRCRAFT DIV., WICHITA.

4.0
KANS.

uOIEO

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HEATING, VENTILATING,
AND DE-ICING
SECTION

.
DRAWING NO.

TITLE: WIRING DIAGRAM---

DRAWN

DATE
APP.D

MODEL

172-P172

0500062
REV:

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV.

13.0

WICHITA, KANS.

FB6

CONTROL SURFACE
SECTION

Cssna,.

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14.4

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WARNING
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SECTION

Cessna.
DRAWING NO.

TITLE:

DRAWN

-.-

DATE
APP'D

WIRING DIAGRAM---

MODEL

172-P172

0500062
REV:

PAGE:

15.0

(C!

MISCELLANEOUS
SECTION

Cessna.
DRAWING NO.

TITLE: WIRING

DRAWN

APP'D

DIAGRAM--EV:

PAGE:

16.0

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

Cessna.
WIRING
DIAGRAM
MODEL
DWG. NO.

180 - 185
0700092

TABLE OF CONTENTS
PAGE NO.

TITLE

DATE ISSUED

REV

1.0

Title Page

2.0
2.1

Table of Contents
Table of Contents

1-16-68
1-16-68

3.0

Notes

11-2-62

4.0
4. 1
4.2
-473
4.4
4.5
4.6
4. 7
4.8
4.9
4.10
4.11
4.12

D.C. Power
Battery, Contactor, Starter & Solenoid
Generator & Regulator
Ground-Service-Receptacle-(Opt-)
Filter (Opt.)
Generating System, 24 Volt (Opt.)
Alternator System, 52 AMP
Wiring Diagram - Alternator System, 60 AMP 12 Volt
Wiring Diagram - Split Bus Bar
Wiring Diagram - External Power Receptacle (Opt.)
Wiring Diagram - Alternator System, 60 AMP 12 Volt
W. D. - 24 Volt Alternator System, 60 AMP
Alternator System, 60 AMP, 12 Volt

11-2-62
6-16-67
3-23-65
1-10-66
3-23-65
6-16-67
2-3-65
6-16-67
11-29-65
6-7-67
8-21-67
6-7-67
8-21-67

D
A-Inac
NC-a.
Inac.
B-Inac
A-Inac
D-Inac
NC
B
A-Inac
NC
NC

5.0
5.1

Ignition
Magneto

11-2-62
12-14-65

6.0

Not Used

7.0
7.1
7.2

Fuel and Oil
Fuel Pump
Oil Dilution Valve (Opt.)

11-2-62
11-21-62
11-2-62

A
NC

8.0
8.1
8. 2
8.2.1

Engine Instruments
Cylinder Head Temp. Gauge
Fuel Gauge and Transmitter
Wiring Diagram - Fuel Gage XMTR & IND. - 12 Volt
Sys.
Carburetor Air Temp. (Opt.)
Cylinder Head Temp Gauge, 24V (Opt.)
Fuel Gage XMTR & IND - 24 Volt Sys.
Wiring Diagram - Fuel Gage XMTR & IND. - 24 Volt
Sys.
Wiring Diagram - Fuel Gage XMTR & Indicators - 12V
Hourmeter (Opt.)

11-2-62
2-17-65
2-17-65

NC-Ina.
NC-Ina.

1-10-66
6-16-67
2-17-65
2-17-65

NC -Ina
B
NC-Ina.
NC-Ina.

6-16-67
1-10-66
9-29-66

A
NC
NC

11-2-62
6-16-67

8.3
8.4
8.5
8.5.1
8.6
8. 7
9.0
9.1

Flight Instruments
Turn and Bank Indicator (Opt.) 12 Volt System
TITLE: WIRING DIAGRAM---

Cessna.
DATE:

2-15-68

MODEL

180-185
PAGE:

DRAWING NO.

0700092
2. 0

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

TABLE OF CONTENTS
TITLE

PAGE NO.

W. D.
W.D.
W.D.
W. D.

9.2
9.3
9.4
9. 5

Optimum Flight Instruments (Opt.)
T & B Indicator - 24 Volt (Opt.)
Brittain Wing Leveler (Opt.)
Turn Coordinator (Opt.)

Other Instruments
Clock (Opt.)
Ammeter (Opt.)

10.0
10. 1
10. 2

Lighting
11.0
Generator Indicator Light
11.1
Landing Lights
11. 2
Rotating Beacon
11. 3
Flashing Beacon Light
11.3.1
Compass & Inst. Lights
11.4
W. C. - Compass & Instrument Lights
11.4.1
Map Light (Opt.)
11.5
Navigation Lights
11.6
Dome Light
11.7
Courtesy Lights (Opt.)
11.8
Position Light Flasher (Opt.)
11.9
Position Light Flasher 24V (Opt.)
11.10
Map & Instrument Light - 24 Volt (Opt.)
11. 11
11. 11.1 Map & Instrument Light (Opt.)
Landing & Taxi Lights (Opt.)
11.12
Wing and Tail Lights
11.13
Courtesy & Dome Lights
11. 14
Map Light, Control Wheel (12 Volt)
11. 15
W. D. - Map Light, Control Wheel (Opt.)
11.16

|
z

DATE ISSUED

REV

2-17-65
2-26-65
6-7-67
9-26-67

NC-I
NC
NC
NC

11-2-62
6-16-67
2-17-65

B
NC-Inac.

11-2-62
2-23-65
1-10-66
6-16-67
6-16-67
6-21-65
6-16-67
3-23-65
1-10-66
1-10-66
1-10-66
3-23-65
3-23-65
6-16-67
6-16-67
6-16-67
1-16-68
6-16-67
9-26-67
9-1-67

NC-In.
A-Inac
B-Inac
A
NC-Inac
A
Inac.
NC -Inac
NC -n.
:.
NCNC-a.
:.
NCC-Inac
A
A
B
A
NC
NC

12.0

Not Used

13.0
13.1
13.1.1
13. 2
13. 3

Heating, Venting & De-Icing
Cigar Lighter
W.D. - Cigar Lighter
Pitot & Stall Warning Heat (Opt.)
Pitot & Stall Warning Heat (Opt.)

11-2-62
2-17-65
3-23-65
1-10-66
8-21-67

14.0

Not Used

5-27-63

15.0
15.1
15. 2
16.0
16.1

Warning & Emergency
Stall Warning Horn & XMTR
Wiring Diagram - Stall Warning Horn & XMTR
Miscellaneous Section
Power Seats Pilot & Co-Pilot (Opt.)

11-2-63
1-10-66
1-10-66
9-27-63
9-27-63

Cessna.
DATE:

TITLE:

2-15-68

A-Inac
NC
NC-Ina
B

A-Inac
NC
NC

WIRING DIAGRAM---DRAWG NO.
MODEL

180-185
I PAGE:

0700092
2.1

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

NOTES
1. WIRE CODE DESIGNATIONS PER CES 1100.
2. WIRE CODE APPLICATION AND WIRE LENGTH TOLERANCES PER CES 1015.
3. "S" SUFFIX ON WIRE GAUGE IN WIRE TABLE DENOTES

SHIELDED WIRE.

5. SHIELDED WIRES TO BE PER MIL-C-7078A, TYPE II, with MIL--5086A TYPE I
CONDUCTOR.
6. "D.S." SUFFIX ON WIRE GAUGE IN WIRE TABLE DENOTES DOUBLE SHIELDED WIRE.
7. WIRES NOTED HEREIN AS (OPT) ARE OPT. TO THE STANDARD AIRPLANE.
8.

ALL WIRES OT SPECIFIED AS (OPT) ARE TO BE INSTALLED AS STANDARD EQUIPMENT.
THE AIRPLANE ASSEMBLY WILL SPECIFY THE ADDITIONAL EQUIPMENT REUIRED FOR
-DELUXE VERSIONS.

WHEN (OPT) IS USED IN TITIE BLOCK OF A DIAGRAM, ALL WIRES SHOWN THEREIN ARE
OPTIONAL EXCEEPT WHERE NOTED AS (STD).

10.

ALL VENDOR CODES PER S-1400.

Cssna.
DRAWING NO.

DRAWN

TITLE: WIRING DIAGRAM---

CESSNA AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV., WICHITA,

KANS.

D. C. POWER
SECTION

Cssa.
_
DRAWN

DATE

TITLE: WIRING DIAGRAM--0-L-6
MODEL
180-185

DRAWING NO.

APPD

CESSNA

V
AIRCRAFT

I
CO..

070002

REV:

COMMERCIAL

AIRCRAFT

|PAGE.

DIV.,

WICHITA,

4.0
KANS.

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HEATING, VENTILATING,
AND DE-ICING
SECTION

WARNING
AND EMERGENCY
SECTION

Cessna.
DRAWING NO.
DRAWN
DATE

AFJ
10-11-62

TITLE: WIRING DIAGRAM--MODEL

180-185

0700092

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

MISCELLANEOUS
SECTION

CDR G NO.

DRAWING NO.
DRAWN

TITLE: WIRING

DIAGRAM---

Cessna,
WIRING
DIAGRAM
MODEL
DWG. NO.

CESSNA

182
0770610

AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV., WICHITA.

KANSAS.

CESSNA AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV., WICHITA. KANS.

TABLE OF CONTENTS
TITLE

PAGE NO.

DATE ISSUED.

REV

1.0

Title Page

2.0
2. 1

Table of Contents
Table of Contents

1-16-68
1-16-68

3.0

Notes

5-1-64

4.0
4.1
4.-1.
4.2
4.3
4.4
4.5
4.6
4. 7

D.C. Power
Battery & External Power Systems
Battery_& External Power Systems
Generator System
Alternator System, 52 AMP
Alternator System, 52 AMP
Alternator System, 60 AMP
Split Bus Bar
Wiring Diagram - Alternator System, 60 AMP

1-13-64
2-8-65
1-31-67
5-1-64
5-1-64
2-8-65
7-8-66
12-22-65
8-21-67

A
B-Ina.
D
NC-In
NC -In
B-Ina.
C-Ina.
NC-In
B

5.0
5. 1
5.2

Ignition
Ignition System
Ignition System

10-18-62
7-23-65
11-12-65

A-Ina.
A

6.0
6. 1

Engine Control
Starter System

10-18-62
12-22-65

7.0
7.1

Fuel & Oil
Oil Dilution System (Opt.)

10-18-62
8-20-64

8.0

Engine Instruments

9-7-62

8. 1
8. 2
8.3
8.4

Cylinder Head Temperature
Fuel Quantity Indicator
Carburetor Air Temp. (Opt.)
Hourmeter (Opt.)

10-20-64
8-20-64
3-4-64
9-29-66

9.0

Flight Instruments Section

10-30-62

9.1
9. 2
9.3
9.4

Turn & Bank & Gyro Horizon Indicator (Opt.)
Not Used
Brittain Wing Leveler (Opt.)
Wiring Diagram - Turn Coordinator (Opt.)

8-20-64

6-7-67
9-25-67

NC
NC

10.0
10. 1
10. 2

Other Instruments
Clock
Wiring Diagram - Flap Position Indicator

10-18-62
4-22-66
2-21-66

C
A

TITLE:

WIRING DIAGRAM---

B
A
A
NC

DRAWING NO.

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

TABLE OF CONTENTS
PAGE NO.

TITLE

DATE ISSUED

REV

11.0
11. 1
11. 2
11.3
11.4
11.5
11.5.1
11.6
11.6.1
11.7
11. 8

Lighting Section
Dome & Courtesy Lights (Opt.)
Instrument Lights & CompassLanding Lights
Navigation Lights
Rotating Beacon (Opt.)
W.D. - Flashing Beacon Light (Opt.)
Map Light (Opt.)
Map Light
Post Lighting & Back Lighting (Opt.)
Nav-O-Matic 300 Post Light (Opt.)

10-30-62
2-2-66
8-7-67
2-21-66
1-16-68
1-29-66
1-29-66
9-3-64
8-7-67
9-22-66
11-18-64

B
C
C
C
A-Inac
NC
A-Ina .
C
B-Inac .
Inac.

11.9

Back Lighting

8-7-67

11.10
11.11

Post Lighting (Opt.)
Map Light, Control Wheel (12 Volt)

11-27-67
9-25-67

B
NC

13.0
13.1
13. 2

Heating, Ventilating, and De-Icing Section
Cigar Lighter
Heated Pitot Tube & Heated Stall Warning System (Opt

10-30-62
9-3-64
10-4-66

B
C

14.0

Control Surface Section

10-30-62

14. 1
14. 2
14.3

Wing Flaps
Wiring Diagram - Wing Flaps - Electric
Wiring Diagram - Wing Flaps

10-26-65
9-13-67
9-13-67

C-Inac.
A-Ina
NC

15.0
15. 1

Warning and Emergency Section
Stall Warning System (Non-heated)

10-30-62
2-21-66

16.0
16.1

Miscellaneous Section
Vertically Adjusting Seat (Opt.)

9-27-63
9-3-64

Cessna.
DATE:

ITITLE:

2-15-68

WIRING DIAGRAM--MODEL 182
PAGE:

DRAWING NO.
0770610
2. 1

CESSNA AIRCRAFT CO., COMMERCIAL AIRCRAFT DIV., WICHITA, KANS.

NOTES
1. WIRE CODE DESIGNATIONS PER CES 1100.
2. WIRE CODE APPLICATION AND WIRE LENGTH TOLERANCES PER CES 1015.
3. "S" SUFFIX ON WIRE GAUGE IN WIRE TABLE DENOTES SHIELDED WIRE.

Conductor.
6. Part numbers shown in the "equipment table" of the various pages are for
reference only and do not constitute a material requirement unless specifically
noted on the individual page. Refer to the various equipment installation
drawings for verification of part numbers.
7. Equipment part numbers shown on the various pages that are for reference only,
(see Note-6), will not- be chaged unless-it-affects-wire-terminals-and-fabr-ication.
8.Vendor codes per S-1400. Vendor codes are shown in parentheses.

Cessna.
DRAWING NO.

D. C. POWER
SECTION

Cessna.
DRAWING NO.

TITLE:

DRAWN
DATE
DATE

APP D

MOD

WIRING DIAGRAM--EL

0770610
770 610
A-E

REV:

PAGE

4.0
4.0

CESSNA AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV.. WICHITA, KANS.

IGNITION
SECTION

ENGINE CONTROL
SECTION

DRAWING NO.

FUEL AND OIL
SECTION

ENGINE INSTRUMENTS
SECTION

SWITCH

[Z~ O.o,
RAT .

NOTE:

CLOCK

FLIGHT INSTRUMENTS
SECTION

DRAWING NO.

D-Ci

DICR)

OTHER INSTRUMENTS
SECTION

LIGHTING
SECTION

DRAWING NO.

0
--

WIRE TABLE

---

rTC~

(Rk-Fr)

"CH4ANGCO

R._"e
.- 8-,RSJ4 TO , ['YKSt-

WIRE TABLE

NOTE5:

ESCpT

WIRE TABLE

PROV

HEATING, VENTILATING,
AND DE-ICING
SECTION

NOTE.

CONTROL SURFACE
SECTION

FLAP SWiTCH

SHOWN

IN FLAP

CO4"

D
P-CC7 16

-CC16

5-341-

25 S-7-

1I-31

5-341-1

________

AREA

R.,< ivj

WARNING
AND EMERGENCY
SECTION

Cessna.
DRAWING NO.

CESSNA AIRCRAFT CO.. COMMERCIAL AIRCRAFT DIV..

WICHITA. KANS.

MISCELLANEOUS
SECTION

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Title                           : D637-1-13 - MODEL 100 - SERIES (1963 THRU 1968)
Subject                         : MODEL 100 - SERIES (1963 THRU 1968)
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D637 1 13 100 SERIES (1963 THRU 1968) Cessna_100_Series_1962 1968_MM_D637 Cessna 1962 1968 MM

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