7400 Service Manual Tennant Rider Floor Scrubber

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7400

Service Manual

MM428

Rev. 04 (3--02)

This service manual is intended to be an aid for the disassembly and reassembly of your TENNANT

Model 7400.

This manual is organized into seven major groups: General Information, Chassis, Scrubbing, Electrical,

Hydraulics, Engine--G/LPG and Engine--D.

General Information: Machine transport, machine jacking, machine storage, machine specifications, and

machine maintenance chart.

Chassis: Tire/wheel replacement, brake adjustment and replacement, chassis lubrication, steering

adjustment and replacement.

Scrubbing: Scrubber head repair/replacement, brush repair/replacement. squeegee repair/replacement,

and scrubber troubling shooting.

Electrical: Battery maintenance and replacement, instrument panel replacement, and electrical

troubleshooting.

Hydraulics: Valve replacement/repair, motor replacement/repair, cylinder replacement/repair, pump

replacement/repair, filter replacement, and hydraulics troubleshooting.

Engine -- G/LPG: Air filter replacement, oil changing, cooling system maintenance/repair, fuel system

maintenance/repair, governor adjustment/repair, engine repair, engine troubleshooting, and engine

repairs.

Engine -- D: Air filter replacement, oil changing, cooling system maintenance/repair, fuel system

maintenance/repair, governor adjustment/repair, engine repair, engine troubleshooting, and engine

repairs.

Manual Number -- MM428

Revision: 04

Published: 3--02

CALIFORNIA PROPOSITION 65 WARNING:

Engine exhaust from this product contains chemicals known to the State of

California to cause cancer, birth defects, or other reproductive harm.

GENERAL INFORMATION

1-1

7400 MM428 (6--01)

CONTENTS

Page

SAFETY PRECAUTIONS 1--3..............

SPECIFICATIONS 1--6....................

GENERAL MACHINE

DIMENSIONS/CAPACITIES 1--6......

GENERAL MACHINE PERFORMANCE1--6

POWER TYPE 1--7.....................

STEERING 1--7........................

HYDRAULIC SYSTEM 1--8..............

BRAKING SYSTEM 1--8................

TIRES 1--8.......................

MACHINE DIMENSIONS 1--9...............

MAINTENANCE 1--10.....................

MAINTENANCE CHART / G/LP 1--10.....

MAINTENANCE CHART / DIESEL 1--12..

PUSHING, TOWING, AND

TRANSPORTING THE MACHINE 1--14...

PUSHING OR TOWING

THE MACHINE 1--14.................

TRANSPORTING THE MACHINE 1--15...

MACHINE JACKING 1--17...............

STORING MACHINE 1--18..............

HARDWARE INFORMATION 1--19..........

STANDARD BOLT TORQUE CHART 1--19

METRIC BOLT TORQUE CHART 1--19...

BOLT IDENTIFICATION 1--19............

THREAD SEALANT AND LOCKING

COMPOUNDS 1--19.................

HYDRAULIC FITTING INFORMATION1--20

HYDRAULIC TAPERED PIPE FITTING (NPT)

TORQUE CHART 1--20..............

HYDRAULIC TAPERED SEAT FITTING (JIC)

TORQUE CHART 1--20..............

HYDRAULIC O--RING FITTING TORQUE

CHART 1--20......................

GENERAL INFORMATION

1-2 7400 MM428 (6--01)

GENERAL INFORMATION

1-3

7400 MM428 (6--01)

SAFETY PRECAUTIONS

The following precautions are used throughout

this manual as indicated in their description:

WARNING: To warn of hazards or

unsafe practices which could result in

severe personal injury or death.

FOR SAFETY: To identify actions which

must be followed for safe operation of

equipment.

The machine is suited to sweep disposable

debris. Do not use the machine other than

described in this Operator Manual. The machine

is not designed for use on public roads.

The following information signals potentially

dangerous conditions to the operator or

equipment:

FOR SAFETY:

1. Do not operate machine:

-- Unless trained and authorized.

-- Unless operator manual is read and

understood.

-- If it is not in proper operating

condition.

-- In flammable or explosive areas unless

designed for use in those areas.

-- In areas with possible falling objects

unless equipped with overhead guard.

2. Before starting machine:

-- Check for fuel, oil, and liquid leaks.

-- Keep sparks and open flame away

from refueling area.

-- Make sure all safety devices are in

place and operate properly.

-- Check brakes and steering for proper

operation.

3. When starting machine:

-- Keep foot on brake and directional

pedal in neutral.

4. When using machine:

-- Use brakes to stop machine.

-- Go slow on inclines and slippery

surfaces.

-- Use care when reversing machine.

-- Do not carry passengers on machine.

-- Always follow safety and traffic rules.

-- Report machine damage or faulty

operation immediately.

5. Before leaving or servicing machine:

-- Stop on level surface.

-- Set parking brake.

-- Turn off machine and remove key.

6. When servicing machine:

-- Avoid moving parts. Do not wear loose

jackets, shirts, or sleeves.

-- Block machine tires before jacking

machine up.

-- Jack machine up at designated

locations only. Block machine up with

jack stands.

-- Use hoist or jack of adequate capacity

to lift machine.

-- Wear eye and ear protection when

using pressurized air or water.

-- Disconnect battery connections before

working on machine.

-- Avoid contact with battery acid.

-- Avoid contact with hot engine coolant.

-- Allow engine to cool.

-- Keep flames and sparks away from

fuel system service area. Keep area

well ventilated.

-- Use cardboard to locate leaking

hydraulic fluid under pressure.

-- Use Tennant supplied or approved

replacement parts.

WARNING: Engine emits toxic gases.

Severe respiratory damage or

asphyxiation can result. Provide

adequate ventilation. Consult with your

regulatory authorities for exposure

limits. Keep engine properly tuned.

WARNING: Flammable materials can

cause an explosion or fire. Do not use

flammable materials in tank(s).

WARNING: Flammable materials or

reactive metals can cause explosion or

fire. Do not pick up.

WARNING: Moving belt and fan. Keep

away.

WARNING: Strong Vacuum. Keep Away

From Fan Inlet When Fan Is Running.

GENERAL INFORMATION

1-4 7400 MM428 (6--01)

The following safety labels are mounted on the

machine in the locations indicated. If these or any

labels become damaged or illegible, install a new

label in its place.

EMISSIONS LABEL -- LOCATED ON THE SIDE

OF THE OPERATOR COMPARTMENT.

10783

FOR SAFETY LABEL -- LOCATED ON THE

SIDE OF THE OPERATOR COMPARTMENT.

FLAMMABLE SPILLS LABEL -- LOCATED ON

THE SIDE OF THE OPERATOR

COMPARTMENT.

GENERAL INFORMATION

1-5

7400 MM428 (6--01)

FAN AND BELT LABEL -- LOCATED ON THE

ENGINE COMPARTMENT LINTEL.

10783

STRONG VACUUM LABEL -- LOCATED ON

THE VACUUM FAN HOUSING.

FLAMMABLE MATERIALS LABEL -- LOCATED

NEXT TO THE SOLUTION TANK COVERS AND

ON THE DETERGENT TANK.

GENERAL INFORMATION

1-6 7400 MM428 (6--01)

SPECIFICATIONS

GENERAL MACHINE DIMENSIONS/CAPACITIES

Item Dimension/capacity

Length 2460 mm (97 in)

Width 1525 mm (60 in)

Width with optional side brush 1590 mm (62.5 in)

Height 1475 mm (58 in)

Height with overhead guard 2045 mm (80.5 in)

Main scrub brush diameter 280 mm (11 in)

Main scrub brush length 1140 mm (45 in)

Side scrub brush diameter (option) 410 mm (16 in)

Squeegee width 1525 mm (60 in)

Scrubbing path width 1140 mm (45 in)

Scrubbing path width with optional side brush 1450 mm (57 in)

Debris tray volume capacity 42L(1.5 ft

Solution tank 265 L (70 gal)

Recovery tank 272 L (72 gal)

Detergent tank (option) 25 L (6.7 gal)

Total capacity with ESt(option) 397 L (105 gal)

GVWR 2087 kg (4600 lb)

GENERAL MACHINE PERFORMANCE

Item Measure

Maximum forward speed 12.9 kmh (8 mph)

Maximum reverse speed 6.4 kmh (4 mph)

Minimum aisle turn width 3190 mm (125.5 in)

Minimum turning radius, right 2660 mm (104.75 in)

Minimum turning radius, left 2030 mm (79.75 in)

Maximum rated incline for scrubbing 6_

Maximum rated incline for transport of machine 8_

GENERAL INFORMATION

1-7

7400 MM428 (6--01)

POWER TYPE

Engine Type Ignition Cycle Aspiration Cylinders Bore Stroke

Kubota

V1505--B (E)

Piston Diesel 4Natural 478 mm

(3.07 in)

78.4 mm

(3.08 in)

Displacement Net power, governed Net power, maximum

1500 cc (91.4 cu in) 24.6 kw (34 hp) @ 2400 rpm 27.2 kw (37.5 hp) @

3000 rpm

Fuel Cooling system Electrical system

Diesel

Fuel tank: 42 L (11.2 gal)

Water/ethylene glycol

antifreeze

12 V nominal

Total: 7.5 L (2 gal) 37 A alternator

Radiator: 3.8 L (1 gal)

Idle speed, no load (Fast) governed speed, under

load

Engine lubricating oil

without filter

950 +50 rpm 2400 +50 rpm 6 L (6.35 qt)

SAE--CC/CD rated

engine oil

Engine Type Ignition Cycle Aspiration Cylinders Bore Stroke

Ford VSG 1.3 Piston Distributorless-

type spark

4Natural 474 mm

(2.91 in)

75 mm

(2.97 in)

Displacement Net power, governed Net power, maximum

1300 cc (79 cu in) 23.2 kw (32 hp) @ 2400 rpm 39.5 kw (53 hp) @

4000 rpm

Fuel Cooling system Electrical system

Gasoline, 87 octane

minimum, unleaded.

Fuel tank: 42 L (11.2 gal)

Water/ethylene glycol

antifreeze

12 V nominal

LPG,

(

)

Total: 7.5 L (2 gal) 50 A alternator

Fuel tank: 15 kg (33 lb) Radiator: 3.8 L (1 gal)

Idle speed, no load (Fast) governed speed, under

load

Firing order

1350 + 250 rpm 2400 + 50 rpm 1--2--4--3,

counterclockwise

rotation

Spark plug gap Valve clearance, cold Engine lubricating oil

with filter

1 mm (0.04 in) 0.20 mm (0.008 in) intake

0.50 mm (0.002 in) exhaust

3.3 L (3.5 qt) 10W30

SAE--SG/SH

GENERAL INFORMATION

1-8 7400 MM428 (6--01)

STEERING

Type Power source Emergency steering

Front wheel, hydraulic cylinder

and rotary valve controlled

Hydraulic accessory pump Manual

HYDRAULIC SYSTEM

System Capacity Fluid Type

Hydraulic reservoir 38 L (10 gal) TENNANT part no. 65869 -- above 7_C(45_F)

Hydraulic total 74 L (19.5 gal) TENNANT part no. 65870 -- below 7_C(45_F)

BRAKING SYSTEM

Type Operation

Service brakes Mechanical drum brakes (2), one per rear wheel,

cable actuated

Parking brake Utilize service brakes, cable actuated

TIRES

Location Type Size Pressure

Front (1) Solid 460 x 130 mm (5 x 18 in) --

Rear (2) Solid 460 x 130 mm (5 x 18 in) --

GENERAL INFORMATION

1-9

7400 MM428 (6--01)

1327 mm

(52.25 in)

2460 mm

(97 in)

2045 mm

(80.5 in)

1475 mm

(58 in)

1525 mm

(60 in)

1260 mm

(49.6 in)

1610 mm

(63.4 in)

1483 mm

(58.4 in)

1686 mm

(66.4 in)

10919

MACHINE DIMENSIONS

GENERAL INFORMATION

1-10 7400 MM428 (6--01)

MAINTENANCE

11 12

MAINTENANCE CHART / G/LP

Interval Key Description Procedure

Lubricant/

Fluid

No. of

Service

Points

Daily 4Engine air filter Check indicator -- 1

Empty dust cap -- 1

4Engine crankcase Check oil level EO 1

8Rear Squeegee Check for damage and wear -- 1

Check deflection -- 1

11 Side Squeegees Check for damage and wear -- 2

10 Scrub brushes Check for damage and wear -- 1

7Recovery tank Clean -- 1

7Recovery tank, EStmode Clean EStfilter -- 1

5Solution tank, EStmode Clean -- 1

50 Hours 10 Scrub brushes Rotate end-for-end or front-to-

rear

-- 1

100 Hours 6Radiator Clean core exterior -- 1

Check coolant level WG 1

4Engine crankcase Change oil and filter element EO 1

13 Cover seals Check for damage and wear -- 4

4Engine Check fan belt tension -- 1

Check and adjust idle speed -- 1

Check and adjust idle mixture -- 1

3Hydraulic fluid reservoir Check fluid level HYDO 1

-- Tires Check for damage -- 3

8Rear squeegee Check leveling -- 1

8Rear squeegee casters Lubricate SPL 2

GENERAL INFORMATION

1-11

7400 MM428 (6--01)

Interval Key Description Procedure

Lubricant/

Fluid

No. of

Service

Points

100 Hours 10 Scrub brush idlers Lubricate SPL 2

10 Scrub head skirts Check for damage and wear -- 2

-- Side brush skirt Check for damage and wear -- 1

200 Hours 6Radiator hoses and clamps Check for tightness and wear -- 2

4Engine fan belt Check tension -- 1

2 Parking brake Check adjustment -- 1

2Brake pedal Check and adjust travel -- 1

1Front wheel

support bearings

Lubricate SPL 2

400 Hours 9Rear wheel bearings Check, lubricate, and adjust SPL 2

4Engine Clean or replace and adjust -- 4

spark plugs

HCheck and adjust valve -- 8

clearance

Check and adjust idle speed -- 1

Check and adjust carburetor -- 1

idle mixture

Replace PCV valve. Clean PCV -- 1

hoses, tubes, and fittings

Fuel filter, gasoline -- 1

800 Hours 3Hydraulic reservoir Replace filler cap -- 1

Replace suction strainer -- 1

Change hydraulic fluid HYDO 1

4Hydraulic fluid filter Change filter element -- 1

-- Hydraulic hoses Check for wear and damage -- All

6 Cooling system Flush WG 1

1Propelling motor HTorque shaft nut -- 1

1Front wheel HTorque wheel nuts -- 1

12 Battery HClean and tighten battery cable -- 1

connections

NOTE: Also check procedures indicted (H) after

the first 50-hours of operation.

NOTE: More frequent intervals may be required

in extremely dusty conditions.

LUBRICANT/FLUID

EO Engine oil, SAE--SG/SH rated....

HYDO Tennant or approved hydraulic fluid.

WG Water and permanent-type ethylene glycol anti-freeze, --34_C(--30_F)...

SPL Special lubricant, Lubriplate EMB grease (TENNANT part no. 01433--1)...

DW Distilled water....

GENERAL INFORMATION

1-12 7400 MM428 (6--01)

11 12

09076

MAINTENANCE CHART / DIESEL

Interval Key Description Procedure

Lubricant/

Fluid

No. of

Service

Points

Daily 4Engine air filter Check indicator -- 1

Empty dust cap -- 1

4Engine crankcase Check oil level EO 1

8Rear Squeegee Check for damage and wear -- 1

Check deflection -- 1

11 Side Squeegees Check for damage and wear -- 2

10 Scrub brushes Check for damage and wear -- 1

7Recovery tank Clean -- 1

7Recovery tank, EStmode Clean EStfilter -- 1

5Solution tank, EStmode Clean -- 1

50 Hours 10 Scrub brushes Rotate end-for-end or front-to-

rear

-- 1

4Fuel pipes and clamps Check for tightness and wear -- 1

100 Hours 6Radiator Clean core exterior -- 1

Check coolant level WG 1

4Engine crankcase Change oil and filter EO 1

4Engine fan belt Check tension -- 1

3Hydraulic fluid reservoir Check fluid level HYDO 1

-- Tires Check for damage -- 3

8Rear squeegee Check leveling -- 1

8Rear squeegee casters Lubricate SPL 2

GENERAL INFORMATION

1-13

7400 MM428 (6--01)

Interval Key Description Procedure

Lubricant/

Fluid

No. of

Service

Points

100 Hours 13 Cover seals Check for damage and wear -- 4

10 Scrub brush idlers Lubricate SPL 2

10 Scrub head skirts Check for damage and wear -- 2

-- Side brush skirt Check for damage and wear -- 1

200 Hours 6Radiator hoses and clamps Check for tightness and wear -- 2

2 Parking brake Check adjustment -- 1

2Brake pedal Check and adjust travel -- 1

1Front wheel Lubricate SPL 2

support bearings

400 Hours 9Rear wheel bearings Check, lubricate, and adjust SPL 2

4Fuel filter Replace cartridge -- 1

6 Cooling system Flush WG 1

800 Hours 3Hydraulic reservoir Replace filler cap -- 1

Replace suction strainer -- 1

Change hydraulic fluid HYDO 1

4Hydraulic fluid filter Change filter element -- 1

-- Hydraulic hoses Check for wear and damage -- All

1Propelling motor HTorque shaft nut -- 1

1Front wheel HTorque wheel nuts -- 1

12 Battery HClean and tighten battery cable -- 1

connections

NOTE: Also check procedures indicted (H) after

the first 50-hours of operation.

NOTE: More frequent intervals may be required

in extremely dusty conditions.

LUBRICANT/FLUID

EO Engine oil, SAE--CC/CD rated....

HYDO Tennant Company or approved hydraulic fluid.

WG Water and permanent-type ethylene glycol anti-freeze, --34_C(--30_F)...

SPL Special lubricant, Lubriplate EMB grease (TENNANT part no. 01433--1)...

DW Distilled water....

GENERAL INFORMATION

1-14 7400 MM428 (6--01)

PUSHING, TOWING, AND TRANSPORTING

THE MACHINE

PUSHING OR TOWING THE MACHINE

If the machine becomes disabled, it can be

pushed from the front or rear, but towed only from

the rear.

The propelling pump has a bypass valve to

prevent damage to the hydraulic system when the

machine is being pushed or towed. This valve

allows a disabled machine to be moved for a very

short distance and at a speed to not exceed 1.6

kp/h (1 mph). The machine is NOT intended to be

pushed or towed a long distance or at a high

speed.

ATTENTION! Do not push or tow

machine for a long distance and without

using the bypass valve, or the machine

hydraulic system may be damaged.

Turn the bypass valve 90_from the normal

position before pushing or towing the machine.

The illustration shows the bypass valve in the

pushing or towing position.

GENERAL INFORMATION

1-15

7400 MM428 (6--01)

TRANSPORTING THE MACHINE

1. Position the rear of the machine at the

loading edge of the truck or trailer.

2. If the loading surface is not horizontal or is

higher than 380 mm (15 in) from the ground,

use a winch to load machine.

If the loading surface is horizontal AND is

380 mm (15 in) or less from the ground, the

machine may be driven onto the truck or

trailer.

3. To winch the machine onto the truck or

trailer, attach the winching chains in the

holes at the bottom of the rear bumper.

If the machine has the optional rear tie down

brackets, attach the winching chains to

them.

4. Turn the bypass valve 90_from the normal

position before winching the machine onto

the truck or trailer. See PUSHING OR

TOWING THE MACHINE section of this

manual. Make sure the machine is centered.

FOR SAFETY: When loading machine

onto truck or trailer, use winch. Do not

drive the machine onto the truck or

trailer unless the loading surface is

horizontal AND is 380 mm (15 in) or less

from the ground.

GENERAL INFORMATION

1-16 7400 MM428 (6--01)

5. Position the machine onto the truck or trailer

as far as possible. If the machine starts to

veer off the centerline of the truck or trailer,

stop and turn the steering wheel to center

the machine.

6. Set the parking brake and block the machine

tires. Tie down the machine to the truck or

trailer before transporting.

The front tie down locations are in the holes

at the bottom of the front bumper. If the

machine has the optional tie down brackets,

use them to tie down the machine.

The rear tie down locations are in the holes

at the bottom of the rear bumper. If the

machine has the optional rear tie down

brackets, use them to tie down the machine.

7. If the loading surface is not horizontal or is

higher than 380 mm (15 in) from the ground,

use a winch to unload machine.

If the loading surface is horizontal AND is

380 mm (15 in) or less from the ground, the

machine may be driven off the truck or

trailer.

FOR SAFETY: When unloading machine

off truck or trailer, use winch. Do not

drive the machine off the truck or trailer

unless the loading surface is horizontal

AND 380 mm (15 in) or less from the

ground.

GENERAL INFORMATION

1-17

7400 MM428 (6--01)

MACHINE JACKING

Empty the recovery and the solution tanks before

jacking the machine.You can jack up the machine

for service at the designated locations. Use a

hoist or jack that will support the weight of the

machine. Always stop the machine on a flat, level

surface and block the tires before jacking the

machine up.

FOR SAFETY: Before leaving or

servicing machine; stop on level

surface, set parking brake, turn off

machine and remove key.

The front jacking location is the left front corner of

the machine frame.

The rear jacking locations are the two rear

corners of the machine frame.

FOR SAFETY: When servicing machine,

block machine tires before jacking

machine up.

FOR SAFETY: When servicing machine,

jack machine up at designated locations

only. Block machine up with jack

stands.

GENERAL INFORMATION

1-18 7400 MM428 (6--01)

STORING MACHINE

When storing the machine for extended periods of

time, the following procedures must be followed to

lessen the chance of rust sludge, or other

undesirable deposits from forming.

1. Drain and clean the solution and recovery

tanks.

2. EStmachines: Run clean water through

the solution system and the EStsolution

pump.

3. Raise the rear squeegee and the scrub

head.

4. Park the machine in a cool, dry area.

5. Remove or charge the battery every three

months.

GENERAL INFORMATION

1-19

7400 MM428 (6--01)

HARDWARE INFORMATION

The following charts state standard plated

hardware tightening ranges for normal assembly

applications. Decrease the specified torque by

20% when using a thread lubricant. Do not

substitute lower grade hardware for higher grade

hardware. If higher grade hardware than specified

is substituted, tighten only to the specified

hardware torque value to avoid damaging the

threads of the part being threaded into, as when

threading into speed nuts or weldments.

STANDARD BOLT TORQUE CHART

Thread

Size

SAE Grade 5

Torque ft lb

(Nm)

SAE Grade 8

Torque ft lb

(Nm)

0.25 in 7--10 (9--14) 10--13 (14--38)

0.31 in 15--20 (20--27) 20--26 (27--35)

0.38 in 27--35 (37--47) 36--47 (49--64)

0.44 in 43--56 (58--76) 53--76 (72--103)

0.50 in 65--85 (88--115) 89--116

(121--157)

0.62 in 130--170

(176--231)

117--265

(159--359)

0.75 in 215--280

(291--380)

313--407

(424--552)

1.00 in 500--650

(678--881)

757--984

(1026--1334)

NOTE: Decrease torque by 20% when using a

thread lubricant.

METRIC BOLT TORQUE CHART

Thread

Size

Class 8.8

Torque ft lb

_Nm)

Class 10.9

Torque ft lb

(Nm)

M4 2(3) 3(4)

M5 4(5) 6(8)

M6 7(9) 10 (14)

M8 18 (24) 25 (34)

M10 32 (43) 47 (64)

M12 58 (79) 83 (112)

M14 94 (127) 133 (180)

M16 144 (195) 196 (265)

M20 260 (352) 336 (455)

M24 470 (637) 664 (900)

NOTE: Decrease torque by 20% when using a

thread lubricant.

Exceptions to the above chart:

Check the machine for exceptions!

BOLT IDENTIFICATION

Identification

Grade Marking

Specification and

Grade

SAE--Grade 5

SAE--Grade 8

ISO--Grade 8.8

ISO--Grade 10.9

01395

THREAD SEALANT AND LOCKING

COMPOUNDS

Thread sealants and locking compounds may be

used on this machine. They include the following:

Locktite 515 sealant -- gasket forming

material. TENNANT Part No. 75567,15 oz

(440 ml) cartridge.

Locktite 242 blue -- medium strength thread

locking compound. TENNANT Part No.

32676, 0.5 ml tube.

Locktite 271 red -- high strength thread

locking compound. TENNANT Part No.

19857, 0.5 ml tube.

GENERAL INFORMATION

1-20 7400 MM428 (6--01)

HYDRAULIC FITTING INFORMATION

HYDRAULIC TAPERED PIPE FITTING (NPT)

TORQUE CHART

NOTE: Ratings listed are when using teflon

thread seal.

Size Minimum

Torque

Maximum

Torque

1/4 NPT 10 ft lb (14 Nm) 30 ft lb (41 Nm)

1/2 NPT 25 ft lb (34 Nm) 50 ft lb (68 Nm)

3/4 NPT 50 ft lb (68 Nm) 100 ft lb (136

Nm)

HYDRAULIC TAPERED SEAT FITTING (JIC)

TORQUE CHART

Tibe O.D.

(in)

Thread Size Maximum

Torque

0.25 0.44--20 9ftlb(12Nm)

0.38 0.56--18 20 ft lb (27 Nm)

0.50 0.75--16 30 ft lb (41 Nm)

0.62 0.88--14 40 ft lb (54 Nm)

0.75 1.12--12 70 ft lb (95 Nm)

1.0 1.31--12 90 ft lb (122 Nm)

HYDRAULIC O--RING FITTING TORQUE

CHART

Tube

O.D.

(in)

Thread

Size

Minimum

Torque

Maximum

Torque

0.25 0.44--20 6ftlb(8Nm) 9ftlb

(12 Nm)

0.38 0.56--18 13 ft lb

(18 Nm)

20 ft lb

(27 Nm)

*10 ft lb

(14 Nm)

12 ft lb

(16 Nm)

0.50 0.75--16 20 ft lb

(27 Nm)

30 ft lb

(41 Nm)

*21 ft lb

(28 Nm)

24 ft lb

(33 Nm)

0.62 0.88--14 25 ft lb

(34 Nm)

40 ft lb

(54 Nm)

0.75 1.12--12 45 ft lb

(61 Nm)

70 ft lb

(95 Nm)

1.0 1.31--12 60 ft lb

(81 Nm)

90 ft lb

(122 Nm)

NOTE: Do not use sealant on o--ring threads.

*Aluminum bodied components

CHASSIS

2-1

7400 MM428 (12--98)

CONTENTS

Page

CHASSIS 2-3............................

SEAT 2-3................................

TO REMOVE SEAT ASSEMBLY 2-3.....

TO REPLACE SEAT ASSEMBLY 2-3.....

OPERATOR SEAT 2-4.................

STATIC DRAG CHAIN 2-4.................

BRAKES AND TIRES 2-5..................

SERVICE BRAKES 2-5.................

TO REPLACE BRAKE SHOES 2-5.......

REAR TIRES AND WHEELS 2-7........

TO REPACK REAR WHEEL

BEARINGS 2-7.....................

FRONT TIRE AND WHEEL, AND

WHEEL SUPPORT 2-9.................

TO REPLACE FRONT DRIVE MOTOR 2-9

TO REPLACE FRONT WHEEL

HOUSING PIVOT BEARINGS 2-11...

CHASSIS

2-2 7400 MM428 (12--98)

CHASSIS

2-3

7400 MM428 (12--98)

INTRODUCTION

This section includes information on the main

chassis related components for example the seat,

steering, brakes, and tires.

CHASSIS

2-4 7400 MM428 (12--98)

SEAT

The seat assembly is adjustable forward and

backward on the 7400.

TO REMOVE SEAT ASSEMBLY

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Tilt the seat assembly forward and engage

theproprod.

2. Remove the four hex screws and nuts

holding the seat assembly hinge to the seat

support.

3. Slide the prop rod to the opening in the slot

and remove.

4. Remove the seat assembly from the

machine.

TO REPLACE SEAT ASSEMBLY

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Position the seat assembly on the seat

support.

2. Reinstall the four hex screws and nuts.

Tighten to 18 -- 24Nm (15 -- 20 ft lb).

3. Slide the seat prop rod through large hole in

slot.

4. Lower the seat.

CHASSIS

2-5

7400 MM428 (12--98)

OPERATOR SEAT

The operator seat is a fixed back style with a

forward-backward adjustment.

Adjust: Pull the lever out, slide the seat

backward or forward to the desired position and

release the lever.

Lift: Pull up on the seat mounting plate until the

seat mount locks up.

Lower: Pull on the release lever and lower the

seat mounting plate.

STATIC DRAG CHAIN

A static drag chain prevents the buildup of static

electricity in the machine. The chain is attached to

the machine with a hex screw by the scrub head

torque tube mount bearing.

Make sure the chain is touching the floor at all

times.

CHASSIS

2-6 7400 MM428 (12--98)

BRAKES AND TIRES

SERVICE BRAKES

The mechanical service brakes are located on the

rear wheels. The brakes are operated by the foot

brake pedal.

Check the brake adjustment every 200 hours of

operation.

TO REPLACE BRAKE SHOES

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Drain the solution and recovery tanks.

2. Make sure the parking brake is not engaged.

3. Remove floor plate from the operators

compartment.

4. Loosen the jam nuts on the brake cable turn

buckle. Rotate the turn buckle to loosen the

tension on the brake cable.

5. Jack up one rear corner of the machine.

Place jack stands under machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

6. Remove the hub cap from the center of the

tire and wheel assembly.

7. Remove the cotter pin, slotted nut, flat

washer, and bearing cone.

8. Remove the tire and wheel assembly from

the machine.

9. Remove the two springs holding the brake

shoes together. Remove the old brake

shoes.

10. Position the new brake shoes on the brake

mounting plate.

11. Reattach the two brake springs to the new

brake shoes.

CHASSIS

2-7

7400 MM428 (12--98)

12. Pack the wheel bearings with Lubriplate

EMB grease.

13. Slide the tire and wheel assembly on the

axle.

14. Slide the outer bearing, flat washer and nut

on the shaft.

15. Tighten nut with hand wrench until wheel

binds, then back nut off to nearest hole.

16. Insert a new cotter pin through nut and hole.

17. Spin the tire and wheel assembly. The tire

should spin freely.

18. Reinstall the hub cap in the center of the

wheel.

19. Lower the machine.

NOTE: Always replace brake shoes in sets.

20. Repeat the procedure on the other wheel.

21. Rotate the brake cable turn buckle until the

brake cable is tight or until the brake pedal

travels 25--50 mm (1--2 in) before engaging

brakes.

22. Tighten the brake cable turn buckle jam

nuts.

23. Reinstall the floor plate in the operators

compartment.

24. Operate the machine and check the brakes

for proper operation.

CHASSIS

2-8 7400 MM428 (12--98)

REAR TIRES AND WHEELS

The standard machine rear tires are

semi--pneumatic.

Inspect the rear wheel bearings for seal damage,

and repack and adjust every 1600 hours of

operation. Use Lubriplate EMB grease

(TENNANT part no. 01433--1).

TO REPACK REAR WHEEL BEARINGS

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Drain the solution and recovery tanks.

2. Make sure the parking brake is not engaged.

3. Remove floor plate from the operators

compartment.

4. Loosen the jam nuts on the brake cable turn

buckle. Rotate the turn buckle to loosen the

tension on the brake cable.

5. Jack up one rear corner of the machine.

Place jack stands under machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

6. Remove the hub cap from the center of the

tire and wheel assembly.

7. Remove the cotter pin, slotted nut, flat

washer, and bearing cone.

8. Remove the tire and wheel assembly from

the machine.

9. Pack the wheel bearings with Lubriplate

EMB grease.

10. Slide the tire and wheel assembly on the

axle.

11. Slide the outer bearing, flat washer and nut

on the shaft.

CHASSIS

2-9

7400 MM428 (12--98)

12. Tighten nut with hand wrench until wheel

binds, then back nut off to nearest hole.

13. Insert a new cotter pin through nut and hole.

14. Spin the tire and wheel assembly. The tire

should spin freely.

15. Reinstall the hub cap in the center of the

wheel.

16. Lower the machine.

17. Repeat the procedure on the other wheel.

18. Rotate the brake cable turn buckle until the

brake cable is tight or until the brake pedal

travels 25--50 mm (1--2 in) before engaging

brakes.

19. Tighten the brake cable turn buckle jam

nuts.

20. Reinstall the floor plate in the operators

compartment.

21. Operate the machine and check the rear

wheels for proper operation.

CHASSIS

2-10 7400 MM428 (12--98)

FRONT TIRE AND WHEEL SUPPORT

The front wheel support pivots the front wheel.

The support has one grease fitting for the

bearings. The front wheel support bearings must

be lubricated every 200 hours of operation. Use

Lubriplate EMB grease

(TENNANT part no. 01433--1).

Torque the front wheel nuts to 142 -- 156 Nm

(105 -- 115 ft lb) after the first 50-hours of

operation, and every 800 hours thereafter.

Torque the front wheel hub nut to (375 ft lb)

TO REPLACE FRONT DRIVE MOTOR

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Engage parking brake, block rear tires.

2. Jack up front of machine. Use jack stands to

support machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

3. Remove the front tire and wheel assembly.

4. Remove the cotter pin and slotted nut from

the front wheel drive motor shaft.

5. Use a puller to remove the drive hub from

the tapered shaft of the drive motor.

6. Remove and plug the hydraulic hoses

leading to the front wheel drive motor.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

7. Remove the four drive motor mounting bolts.

8. Slide the motor out of front wheel housing.

CHASSIS

2-11

7400 MM428 (12--98)

9. Remove the hydraulic fittings from the old

motor and install in the new motor in the

same orientation.

10. Slide the new motor in the front wheel

housing. Note the orientation of the motor.

11. Reinstall the four socket--head screws.

Torque to 90 -- 117 Nm (70 -- 85 ft lb).

12. Reconnect the hydraulic hoses to the drive

motor.

NOTE: Make sure the square key is in place on

the shaft of the new motor.

13. Mount the drive hub to tapered motor shaft.

Tighten slotted nut to 500 Nm (375 ft lb).

Install the cotter pin.

14. Install the front tire. Torque the front wheel

nuts to 142 -- 156 Nm (105 -- 115 ft lb).

15. Remove jack stands and lower machine.

16. Operate the machine and check the front

drive motor for any leaks.

CHASSIS

2-12 7400 MM428 (12--98)

TO REPLACE FRONT WHEEL HOUSING

PIVOT BEARINGS

1. Engage parking brake, block rear tires.

2. Disconnect the battery cables from the

battery.

3. Jack up front of machine. Use jack stands to

support machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

4. Remove the front tire and wheel assembly.

5. Remove and plug the hydraulic hoses

leading to the front wheel drive motor.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

6. Remove the hydraulic hose clamp from the

top of the wheel housing.

7. Remove the one 3/4 in. hex screw attaching

the rod end of steering cylinder to the front

wheel housing. Retain the spacer.

8. Remove the cotter pin and large slotted nut

from the top of the pivot pin.

9. Loosen the two M10 socket head bolts

holding the pivot pin to the machine frame.

NOTE: Use a floor jack to support the wheel

housing before removing the pivot pin. The wheel

housing and drive motor assembly is very heavy.

10. Remove the pivot pin from the bottom of the

wheel support.

NOTE: Do not loose the thrust washer from on

top of the wheel housing.

11. Remove the wheel housing and drive motor

assembly out of the main frame.

12. Use a steel punch and hammer to drive the

old bearing cups out of the wheel housing.

CHASSIS

2-13

7400 MM428 (12--98)

13. Install a new set of bearing cups in the

wheel housing. Use a large press or a punch

and hammer to install the cups.

14. Pack the new bearing cones with Lubriplate

EMB grease. Coat the bearing cups with

grease.

15. Position the new bearing cones in the wheel

housing.

16. Position the thrust washer on top of the

upper bearing cone.

17. Position the wheel housing back in the

machine.

18. Slide the large pivot pin up through hole in

the machine frame. Thread castle nut on the

top of the pivot pin. Tighten to 34 -- 40 Nm

(25 -- 30 ft lb). Check the wheel housing for

play. If pin is not seated, tap with rubber

mallet and re--torque castle nut.

NOTE: The wheel housing should rotate with a

slight amount of drag.

19. Torque the top socket screw with a hand

torque wrench to 100 -- 115 Nm

(73--85 ft lb).

20. Tighten the castle nut to the next slot and

insert the cotter pin. Torque not to exceed

100 Nm (75 ft lb).

21. Check the casting to see if it rocks or binds.

If it does, loosen top socket screw, move the

casting to seat the bearings, and re--tighten

the socket screw to 100 -- 115 Nm

(73--85 ft lb).

22. Tighten the lower socket screw to

100 -- 115 Nm (73--85 ft lb).

23. Reinstall rod end of steering cylinder to the

top of the wheel housing using the 3/4 in. x

3--1/4 in. hex screw,nyloc nut, and four flat

washers. Tighten to 270 -- 300 Nm

(200 -- 220 ft lb).

CHASSIS

2-14 7400 MM428 (12--98)

24. Reconnect the hydraulic hoses to the drive

motor.

25. Reinstall the hose clamp to the top of the

wheel housing. Tighten M8 hex screws to

18.5 -- 24Nm (15 -- 20 ft lb).

26. Install the front tire. Torque the front wheel

nuts to 142 -- 156 Nm (105 -- 115 ft lb)

27. Re--connect battery cables, start engine, run

propelling in both directions, check for leaks.

28. Remove jack stands, lower machine to the

ground.

SCRUBBING

3-1

7400 MM428 (9--01)

CONTENTS

Page

INTRODUCTION 3-3...................

SOLUTION TANKS 3-4....................

TO REMOVE LH SOLUTION TANK 3-4...

TO INSTALL LH SOLUTION TANK 3-5...

TO REMOVE RH SOLUTION TANK 3-6..

TO INSTALL RH SOLUTION TANK 3-7...

RECOVERY TANK 3-8....................

TO REMOVE RECOVERY TANK 3-8.....

TO INSTALL RECOVERY TANK 3-11.....

SCRUB HEAD 3-13.......................

TO REPLACE MAIN SCRUB

BRUSHES 3-13.....................

CHECKING AND ADJUSTING SCRUB

BRUSH PATTERN 3-14..............

TO REPLACE MAIN BRUSH IDLER

SHAFT BEARINGS 3-16.............

TO REMOVE MAIN BRUSH DRIVE

MOTOR MOUNT PLATE 3-18........

TO INSTALL MAIN BRUSH DRIVE

MOTOR MOUNT PLATE 3-19........

TO REPLACE OPTIONAL SIDE

BRUSH 3-20.......................

SQUEEGEES 3-21........................

TO REPLACE REAR SQUEEGEE

LIFT CABLE 3-21...................

TO REPLACE REAR SQUEEGEE

CENTERING SPRINGS 3-22.........

TO REMOVE REAR SQUEEGEE

FRAME 3-23.......................

TO INSTALL REAR SQUEEGEE

FRAME 3-23.......................

SQUEEGEE BLADES 3-24................

REAR SQUEEGEE 3-24................

TO REPLACE OR ROTATE REAR

SQUEEGEE BLADES 3-24...........

TO ADJUST REAR SQUEEGEE

BLADE DEFLECTION 3-25...........

TO LEVEL THE REAR SQUEEGEE 3-26.

SIDE SQUEEGEES 3-27...............

TO REPLACE SIDE SQUEEGEE

BLADES 3-27.......................

TO REPLACE SIDE BRUSH

SQUEEGEE 3-28...................

SIDE BRUSH SKIRT 3-28...............

VACUUM FAN 3-29.......................

TO REMOVE VACUUM FAN 3-29........

TO INSTALL VACUUM FAN 3-30........

TO REPLACE VACUUM IMPELLER 3-31.

SCRUBBING

7400 MM428 (12--98)

3-2

SCRUBBING

3-3

7400 MM428 (12--98)

INTRODUCTION

When the scrubbing mode is used, water flows

from the solution tank through the solution valve

to the two cylindrical scrub brushes. The brushes

scrub the floor. As the machine is moved forward

the squeegee wipes the dirty solution off the floor,

which is then picked up and drawn into the

recovery tank by the vacuum fan. There are three

settings on the solution flow----high, low, and off.

SCRUBBING

3-4 7400 MM428 (12--98)

SOLUTION TANKS

The two solution tanks hold the clean water and

detergent mixture that will be applied to the floor

for the scrubbing operation. There is a LH and a

RH solution tank. They are connected by a large

diameter solution line.

TO REMOVE LH SOLUTION TANK

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Empty the solution and recovery tanks.

2. Open the engine side door and engine

cover.

3. Unlatch the rear radiator cover panel and tilt

it open.

4. Disconnect the wires going to the float

switch at the back of the LH solution tank.

5. Remove the two hex screws from the rear

tank bracket where it attaches to the LH

solution tank.

6. Remove the one hex screw from the rear,

lower corner of the LH tank. This hex screw

is located near the left hand taillight.

7. Go to the front of the LH solution tank.

Disconnect the solution cross--over line from

the bottom, front of the LH solution tank.

NOTE: Access the the clamp on the cross--over

line is made easier by removing the two vacuum

hoses leading to the recovery tank.

8. Remove the two M8 hex screws from the

front of the LH solution tank near the engine

alternator.

9. The LH solution tank can now be lifted up

and out of the machine frame.

SCRUBBING

3-5

7400 MM428 (12--98)

TO INSTALL LH SOLUTION TANK

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Position the LH solution tank back in the

machine frame.

NOTE: Be careful not to pinch hydraulic hoses or

electrical wires during this procedure.

2. Reinstall the two M8 hex screws in the front

of the LH solution tank near the engine

alternator. Leave hardware loose for now.

3. Reinstall the two M8 hex screws in the top,

rear of the LH solution tank in the rear tank

bracket. Leave hardware loose for now.

4. Reinstall the one M8 hex screw in the rear,

bottom of the LH solution tank near the LH

taillight.

5. Tighten the five M8 hex screws to

18 -- 24 Nm (15 -- 20 ft lb).

6. Reconnect the solution cross--over line at

the bottom of the tank.

NOTE: Reconnect the vacuum hoses if removed

earlier.

7. Reconnect the wires to the float switch at

the back of the LH solution tank.

8. Close the rear radiator cover panel and

latch.

9. Close the engine side door and engine

cover.

10. Fill the LH solution tank with water and

check for leaks.

SCRUBBING

3-6 7400 MM428 (12--98)

TO REMOVE RH SOLUTION TANK

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. The RH solution tank can only be removed

after the LH solution and recovery tanks

have been removed. See TO REMOVE LH

SOLUTION TANK and TO REMOVE

RECOVERY TANK instructions.

2. Remove the one hex screw from the rear,

lower corner of the RH tank. This hex screw

is located under the frame, above the drain

cap.

3. Place the operators seat in the raised

position and engage the prop rod.

4. Remove the two M8 hex screws from the

front, right corner of the RH solution tank

where it attaches to the seat support.

5. Disconnect any solution lines still attached to

the RH solution tank.

6. The RH solution tank can now be lifted up

and out of the machine frame.

SCRUBBING

3-7

7400 MM428 (12--98)

TO INSTALL RH SOLUTION TANK

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Position the RH solution tank back in the

machine frame.

NOTE: Be careful not to pinch hydraulic hoses or

electrical wires during this procedure.

2. Reinstall the one M8 hex screw in the rear,

bottom of the RH solution tank. This hex

screw is located under the frame, above the

drain cap. Leave hardware loose for now.

3. Reinstall the two M8 hex screws from the

front, right corner of the RH solution tank

where it attaches to the seat support. Leave

hardware loose for now.

4. Reconnect any solution lines that were

disconnected from the RH solution tank.

5. The remain RH solution tank hardware will

be installed during the recovery tank

installation. See TO INSTALL RECOVERY

TANK and TO INSTALL LH SOLUTION

TANK instructions.

SCRUBBING

3-8 7400 MM428 (12--98)

RECOVERY TANK

The recovery tank holds the used water and

detergent solution pulled off the floor by the

squeegee and scrubbing vacuum fan.

TO REMOVE RECOVERY TANK

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Empty the solution and recovery tanks.

2. Place the operators seat in the raised

position and engage the prop rod.

3. Remove the LH solution tank. See TO

REMOVE LH SOLUTION TANK

instructions.

4. Disconnect the vacuum and squeegee

hoses from the front of the recovery tank.

5. Remove the two hex screws holding the

demister cover on the recovery tank.

Remove the demister cover.

6. If the machine is equipped with an overhead

guard, it must be removed in order to

remove the tank lintel.

NOTE: The engine hood must be supported in the

open position before the next step can be

completed.

7. Remove the clips on the bottom of the

engine hood gas springs. Remove the gas

springs from the ball studs on the support

channel.

8. Remove the hex screws holding the support

channel to the tank lintel and hood lintel.

Remove the support channel from the

machine.

SCRUBBING

3-9

7400 MM428 (12--98)

9. Remove the solution and recovery tank drain

caps from the rear of the machine.

10. Remove the three hex screws holding the

tank drain cover to the machine. Remove

the cover.

11. Remove the hex screws holding the tank

lintel to the frame, recovery tank, RH

solution tank, and seat support. Remove the

lintel from the machine.

12. Mark, disconnect, and plug the three

hydraulic hoses leading to the engine fan

hydraulic motor.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

13. Disconnect the solution line at the front of

the recovery tank if the machine is equipped

with the auto--fill option.

14. Disconnect the wires leading to the float

switch that is located at the front, right

corner of the recovery tank.

NOTE: Machines equipped with ES will have two

switches on the float assembly.

15. Disconnect the solution hose at the back of

the tank if the machine is equipped with the

EStoption.

16. Unplug the main electrical harness from the

EStpump at the rear of the tank.

17. Remove the EStpump and cap assembly

from the recovery tank.

18. Remove the one hex screw and two nyloc

nuts holding the radiator assembly to the

back of the recovery tank. Leave the black

mount plate attached to the recovery tank.

Do not disconnect the hoses from the

radiator.

SCRUBBING

3-10 7400 MM428 (12--98)

19. Carefully pull the radiator assembly back

and out of the way of the recovery tank. Let

the radiator assembly lean against the oil

cooler.

20. Remove the two M8 hex screws attaching

the rear tank bracket to the RH solution tank

21. Remove the one M8 hex screw under the

rear of the tank, just above the drain cap.

22. Carefully push the recovery tank forward, lift

it up, and remove it from the machine.

NOTE: An overhead hoist or two people must be.

used when lifting the recovery tank out of the

machine frame.

SCRUBBING

3-11

7400 MM428 (12--98)

TO INSTALL RECOVERY TANK

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

NOTE: An overhead hoist or two people must be

used when positioning the recovery tank back in

the machine frame.

1. Position the recovery tank back in the

machine frame.

NOTE: Be careful not to pinch hydraulic hoses or

electrical wires during this procedure.

2. Reinstall the tank lintel in the machine.

Reinstall the six M8 hex screws. Leave the

hardware loose for now.

3. Reconnect the solution line at the front of

the recovery tank if machine is equipped

with the auto fill option.

4. Reconnect the float switches at the front of

the recovery tank to the main harness. See

schematic in the ELECTRICAL section.

5. Carefully pivot the radiator assembly back in

position on the rear of the recovery tank.

Reinstall the hardware and tighten to

18 -- 24 Nm (15 -- 20 ft lb).

6. Plug the EStpump back in the main

harness. See schematic in the

ELECTRICAL section.

7. Reinstall the hardware in the rear tank

bracket where it attaches to the RH solution

tank.

8. Reinstall the one M8 hex screw under the

rear of the tank, just above the drain cap.

9. Reinstall the support channel to the tank

lintel and hood lintel. Reinstall the four M8

hex screws.

10. Tighten the all of the M8 hex screws to

18 -- 24 Nm (15 -- 20 ft lb).

SCRUBBING

3-12 7400 MM428 (12--98)

11. Reinstall the engine hood gas springs on the

ball studs on the support channel. Reinstall

the two clips.

12. Reconnect the hydraulic hoses to the engine

fan motor. See schematic in the

HYDRAULIC section.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

13. Reinstall the demister cover on the recovery

tank. Reinstall the two M8 hex screws and

tighten to 18 -- 24 Nm (15 -- 20 ft lb).

14. Reinstall the LH solution tank. See TO

INSTALL LH SOLUTION TANK instructions.

15. Reconnect the two vacuum hoses to the

front of the recovery tank.

16. Reinstall the overhead guard if it was

removed earlier.

17. Reinstall the tank drain cover to the rear of

the tanks. Reinstall the hardware and tighten

to 18 -- 24 Nm (15 -- 20 ft lb).

18. Reinstall the solution and recovery tank

drain covers.

19. Partially fill the recovery tank with water and

check for any leaks and for proper operation

of the float switches.

SCRUBBING

3-13

7400 MM428 (12--98)

SCRUB HEAD

The scrub head contains the two cylindrical

brushes, hydraulic motors, brush idler plate, brush

wrap, and side squeegees. Water from the

solution tank flows to the center of of the scrub

head brush wrap and is spread evenly in front of

the scrub brushes.

TO REPLACE MAIN SCRUB BRUSHES

1. Place the main scrub brushes in the raised

position.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

2. Open the RH brush door.

3. Pull back on the front ball joint locking collar

on the leveling rod. Remove the leveling rod

from the front ball stud.

4. Remove the two hair pins from the brush

wrap attachment pins.

5. Remove the M12 hex screw holding the

brush idler plate arm to the lift tube.

6. Remove the idler plate and side squeegee

assembly from the machine.

NOTE: Thread the mounting bolt into the idler arm

removal hole if you are having trouble removing

the idler arm.

7. Pull the two main brushes off the drive

plugs.

6. Line up the drive end of the new or rotated

brushes with the brush drive plugs. The

cylindrical scrub brushes must be installed

with the V-patterns on the brushes pointing

towards each other. Slide the brushes onto

the brush drive plugs.

8. Reinstall the idler plate and side squeegee

assembly in the machine.

NOTE: Lift up on the brush wrap slightly when

installing the idler plate in the machine so the

attachment pins line up with the holes in the plate.

SCRUBBING

3-14 7400 MM428 (12--98)

9. Align the two pins on the lift tube with the

two holes in the brush idler plate arm.

10. Reinstall the M12 hex screw in the brush

idler plate arm. Tighten to 64 -- 83 Nm

(47 -- 61 ft lb).

NOTE: Apply a small amount of grease to the

threads on the bolt and in the tube.

11. Reinstall the two hair pins in the brush wrap

attachment pins.

12. Reconnect the front of the leveling rod to the

ball stud.

13. Close the RH brush door and operate the

machine. Check the main brushes for proper

operation.

CHECKING AND ADJUSTING SCRUB BRUSH

PATTERN

1. Apply chalk, or some other material that will

not easily blow away, to a smooth, level

floor.

2. Raise the scrub head. Position the scrub

head over the chalked area.

3. Set the parking brake.

4. Lower the scrub head for 15 to 20 seconds

while keeping the scrub head in one spot in

the chalked area.

NOTE: If chalk or other material is not available,

allow the brushes to spin on the floor for two

minutes. A polish mark will remain on the floor.

5. Raise the scrub head, release the parking

brake, and drive the machine away from the

chalked area.

6. Observe the width of the brush pattern. If

the brush patterns have parallel sides and

are the same width, the brushes do not need

taper adjustment.

If one or both of the brush patterns are

tapered, the scrub head will have to be

adjusted to straighten the brush pattern.

10355

10652

SCRUBBING

3-15

7400 MM428 (12--98)

7. Loosen the three scrub head mounting bolts

on the idler or drive side of the scrub head.

Move the scrub head up to decrease the

pattern width on that side of the scrub head.

Move the scrub head down to increase the

pattern width on that side of the scrub head.

Tighten the mounting bolts and check the

pattern again and readjust if necessary.

The brush patterns should be the same

width. If one is narrower then the other, the

scrub head needs to be leveled from front to

rear.

8. Lengthen or shorten the leveling rods on

both sides of the scrub head. Lengthening

the rods will increase the rear brush pattern

width. Shortening the rods will will increase

the front brush pattern.

10653

SCRUBBING

3-16 7400 MM428 (12--98)

TO REPLACE MAIN BRUSH IDLER SHAFT

BEARINGS

1. Place the main scrub brushes in the raised

position.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

2. Open the RH brush door.

3. Pull back on the front ball joint locking collar.

Remove the leveling rod from the front ball

stud.

4. Remove the two hair pins from the brush

wrap attachment pins.

5. Remove the M12 hex screw holding the

brush idler plate arm to the lift tube.

6. Remove the idler plate and side squeegee

assembly from the machine.

NOTE: For better access to the shaft and

bearings----remove the C--clip and brush arm from

the idler plate.

7. Turn the idler plate and side squeegee

assembly over. Remove the cotter pins,

castle nuts, and washers from the idler

plugs.

8. Use a puller to remove the idler plugs from

the tapered shafts. Remove and retain the

square key.

9. Remove the retaining rings from both ends

of the idler shafts.

10. Use a press to remove the tapered shafts

from the idler plate. Push the shafts out

toward the direction of the idler plugs.

NOTE: Use a small amount of heat in the area of

the bearings to help break the loctite loose.

11. Use a press to remove the bearing from the

tapered end of the idler shaft.

12. Use a press to remove the bearing from the

bearing housing in the idler plate. Discard

the old bearings.

13. Use a press to install a new bearing in the

bearing housing on the outside of the idler

plate. The open face of the bearing points in.

Use green loctite #680 on the outer diameter

of the bearing before pressing in place.

SCRUBBING

3-17

7400 MM428 (12--98)

14. Use a press to install a new bearing on the

tapered shaft. The open face of the bearing

points in. Reinstall the retaining ring on the

tapered shaft next to the bearing.

15. Reinstall the tapered shaft and bearing in

the bearing housing on the inside of the

idler plate. Use green loctite #680 on the

outer diameter of the bearing before

pressing in place.

16. Reinstall the retaining ring on the flat end of

the tapered shaft on the outside of the idler

plate.

17. Reinstall the square key on the tapered

shaft. Put a small amount of grease on the

taper.

18. Reinstall the idler plugs, washers, and castle

nuts. Hold the plug from turning and tighten

the castle nut down hard until the slot in the

nut lines up with the hole in the shaft. Install

a new cotter pin.

19. Reinstall the brush arm and C clip if they

were removed earlier.

20. Reinstall the idler plate and side squeegee

assembly in the machine.

NOTE: Lift up on the brush wrap slightly when

installing the idler plate in the machine so the

attachment pins line up with the holes in the plate.

21. Align the two pins on the lift tube with the

two holes in the brush idler plate arm.

22. Reinstall the M12 hex screw in the brush

idler plate arm. Tighten to 64 -- 83 Nm

(47 -- 61 ft lb).

NOTE: Apply a small amount of grease to the

threads on the bolt and in the tube.

23. Reinstall the two hair pins in the brush wrap

attachment pins.

24. Reconnect the front of the leveling rod to the

ball stud.

25. Close the RH brush door and operate the

machine. Check the main brushes for proper

operation.

SCRUBBING

3-18 7400 MM428 (12--98)

TO REMOVE MAIN BRUSH DRIVE MOTOR

MOUNT PLATE

1. Place the main scrub brushes in the raised

position.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

2. Open the LH brush door.

3. Remove the front ball joint on the leveling

rod from the machine frame.

4. Remove the two hair pins from the brush

wrap attachment pins.

5. Remove the M12 hex screw holding the

brush arm to the lift tube.

6. Remove the three hex screws holding the

side squeegee assembly to the motor mount

plate. Remove the side squeegee assembly.

NOTE: For better access to the hydraulic drive

motors----remove the C--clip and brush arm from

the motor plate.

7. Mark, disconnect, and plug the three

hydraulic hoses leading to the main brush

drive motors.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

8. Remove the motor mount plate assembly

from the machine.

SCRUBBING

3-19

7400 MM428 (12--98)

TO INSTALL MAIN BRUSH DRIVE MOTOR

MOUNT PLATE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Position the motor plate assembly back in

the machine.

NOTE: Lift up on the brush wrap slightly when

installing the motor plate in the machine so the

attachment pins line up with the holes in the plate.

2. Reinstall the two hair pins in the brush wrap

attachment pins.

3. Reconnect the hydraulic hoses to the brush

motors. See schematic in HYDRAULICS

section.

4. Reinstall the brush arm and C clip if they

were removed earlier.

5. Align the two pins on the lift tube with the

two holes in the brush motor plate arm.

6. Reinstall the M12 hex screw in the brush

motor plate arm. Tighten to 64 -- 83 Nm

(47 -- 61 ft lb).

NOTE: Apply a small amount of grease to the

threads on the bolt and in the tube.

7. Reinstall the front of the leveling rod ball

joint to the machine frame.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

8. Reinstall the side squeegee assembly to the

motor plate. Tighten the three hex screws to

37 -- 48 Nm (26 -- 34 ft lb).

9. Close the LH brush door and operate the

machine. Check the main brush motors for

proper operation.

SCRUBBING

3-20 7400 MM428 (12--98)

TO REPLACE OPTIONAL SIDE BRUSH

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Rotate the side brush by hand until the

spring clips are visible through the window in

the side brush motor mount plate.

2. Reach in through the opening in the top of

the side brush guard, through the mount

plate window, and pinch the spring clips

together.

3. Drop the brush off the drive hub. Remove

the brush from the machine.

4. Position the new side brush under the

machine.

5. Lift the side brush and line up the hub in the

brush with the motor drive plug. Snap the

brushupinplace.

6. Operate the machine and check the side

brush for proper operation.

SCRUBBING

3-21

7400 MM428 (12--98)

SQUEEGEES

The squeegee channels water into the vacuum

fan suction. The front blade channels the water,

and the rear blade wipes the floor.

There are two types of squeegee blades

available; one for smooth surfaces is standard on

the machine, and one for rough surfaces is an

option.

The side squeegees control water spray and

channel water into the path of the rear squeegee.

Check the side squeegees for damage and wear

daily.

TO REPLACE REAR SQUEEGEE LIFT CABLE

1. Open the debris tray latch and swing the

squeegee assembly out for better access.

2. Start engine, lower rear squeegee, shut off

engine.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Remove the cotter pin and clevis pin from

the squeegee lift cable where it attaches to

the squeegee frame assembly.

4. Remove the cotter pin and clevis pin from

the squeegee lift cable where it attaches to

the squeegee lift bellcrank located near the

lift cylinder.

5. Remove the clevis pin holding the cable

roller to the frame. Remove the roller.

6. Remove and discard the old squeegee lift

cable.

7. Position the new cable in the machine.

Reinstall one end to the squeegee lift

bellcrank located near the lift cylinder.

Re--use the clevis and cotter pin.

8. Reinstall the other end to the squeegee pivot

frame assembly. Re--use the clevis and

cotter pin.

9. Reinstall the cable roller and clevis pin in the

frame.

10. Start the machine and raise the squeegee.

Swing the squeegee assembly back in.

Check the lift cable for proper operation.

SCRUBBING

3-22 7400 MM428 (12--98)

TO REPLACE REAR SQUEEGEE

CENTERING SPRINGS

1. Open the debris tray latch and swing the

squeegee assembly out for better access.

2. Start engine, lower rear squeegee, shut off

engine.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Loosen the jam nuts on the squeegee down

pressure spring rods. This will relax the

tension on the springs.

4. Remove the nyloc nuts from the squeegee

rod ball joints where they are connected to

the debris tray.

NOTE: Remove both the upper and lower nuts on

one side. Do one side at a time.

5. Remove and discard the old squeegee

centering spring.

6. Position a new squeegee centering spring

on the upper and lower ball joint studs.

7. Reinstall the two nyloc nuts and tighten to

37 -- 48 Nm (26 -- 34 ft lb).

8. Repeat this procedure on the other side if

needed.

9. Start the machine and raise the squeegee.

Swing the squeegee assembly back in.

Check the centering springs for proper

operation.

SCRUBBING

3-23

7400 MM428 (12--98)

TO REMOVE REAR SQUEEGEE FRAME

1. Open the debris tray latch and swing the

squeegee assembly out for better access.

2. Start engine, lower rear squeegee, shut off

engine.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Remove vacuum hose from squeegee

frame.

4. Remove the cotter pin and clevis pin from

the squeegee lift cable where it attaches to

the squeegee frame assembly.

5. Loosen the jam nuts on the squeegee down

pressure spring threaded rods. This will

relax the tension on the springs.

6. Remove the four hex screws and nuts

holding the squeegee frame to the squeegee

lift assembly.

7. Remove the squeegee frame from the

machine.

TO INSTALL REAR SQUEEGEE FRAME

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Position the squeegee frame back under the

lift assembly.

2. Reinstall the four hex screws and nuts.

Tighten to 37 -- 48 Nm (26 -- 34 ft lb).

3. Re--connect the squeegee lift cable to the

frame assembly. Re--use the clevis and

cotter pin.

4. Re--apply tension on the down pressure

springs using the threaded rods and jam

nuts.

5. Reinstall the vacuum hose on the squeegee

frame.

6. Start the machine and raise the squeegee.

Swing the squeegee assembly back in.

SCRUBBING

3-24 7400 MM428 (12--98)

SQUEEGEE BLADES

REAR SQUEEGEE

Check the squeegee blades for damage and wear

daily. Rotate or replace either of the squeegee

blades if the leading edge is torn or worn half-way

through the thickness of the blade.

The rear squeegee has two squeegee blades.

Each blade has four wiping edges. To use them

all, start with one wiping edge. To use the next

wiping edge, rotate the blade end-for-end. To use

the next wiping edge, rotate the top edges down,

bottom edges up. To use the last edge, rotate the

blade end-for-end.

Replace any worn or damaged squeegee blades.

TO REPLACE OR ROTATE REAR

SQUEEGEE BLADES

1. Make sure the squeegee is raised off the

floor.

2. Shut the engine off and set the parking

brake.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Open the retaining band clamp and remove

the squeegee blade.

4. Replace or rotate the squeegee blade to

allow a new edge to face the front of the

machine.

5. Place the squeegee blade over the pins of

the squeegee frame.

6. Position the retaining band over the

squeegee blade. Latch the retaining band

clamp.

7. Adjust the squeegee blade leveling and

deflection. See TO ADJUST REAR

SQUEEGEE BLADE DEFLECTION or TO

LEVEL THE REAR SQUEEGEE

instructions.

SCRUBBING

3-25

7400 MM428 (12--98)

TO ADJUST REAR SQUEEGEE BLADE

DEFLECTION

Deflection is the amount of curl the squeegee

blade has when the machine travels forward with

the squeegee lowered to the floor. The best

deflection is when the squeegee wipes the floor

just dry with a minimum amount of deflection.

1. Lower the squeegee and drive the machine

forward.

2. Shut off the engine and set the machine

parking brake.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Look at the deflection over the full length of

the squeegee blade. The correct amount of

deflection for the rear squeegee blade is

15 to 20 mm (0.50 to 0.75 in). The front

slotted squeegee blade should contact the

floor with a slight deflection, 5 mm (0.13 to

0.25 in).

4. To adjust the amount of deflection, unlock

the height adjustment knobs on the two

squeegee casters by sliding the locking

bracket off to the side.

NOTE: If the locking brackets won’t slide over, lift

up the end of the squeegee to pick the caster up

off the floor slightly. Then slide the locking bracket

over.

5. Turn the adjustment knob clockwise to

decrease deflection, turn the adjustment

knob counter-clockwise to increase the

deflection. Be sure to turn the knobs the

same number of turns.

6. Start the engine and drive the machine

forward again to check the squeegee blade

deflection. Readjust the squeegee blade

deflection if necessary.

7. Slide the locking brackets back to lock the

height adjustment knobs.

8. Raise the squeegee when finished.

10918

15 to

20 mm

(0.50 to

0.75 in)

5mm

(0.13 to

0.25 in)

SCRUBBING

3-26 7400 MM428 (12--98)

TO LEVEL THE REAR SQUEEGEE

Leveling of the squeegee assures even contact

over the length of the squeegee blade with the

surface being scrubbed. Make sure this

adjustment is done on an even, level floor.

1. Lower the squeegee and drive the machine

forward.

2. Shut off the engine and set the machine

parking brake.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Look at the deflection over the full length of

the squeegee blade.

4. If the deflection is not the same over the full

length of the blade, loosen the locking nut on

the two rear squeegee balljoints.

NOTE: The rear squeegee links should be

adjusted so there is 11 inches from the center

lines of the two ball joints.

5. Turn the balljoint adjustment nut clockwise,

from the rear of the machine, to increase the

deflection at the ends of the squeegee. Turn

the balljoint adjustment nut

counter-clockwise, from the rear of the

machine, to decrease the deflection at the

ends of the squeegee blade.

6. Tighten the locking nuts.

7. Start the engine and drive the machine

forward again to check the squeegee blade

deflection.

8. Readjust the squeegee blade deflection if

necessary.

11.00 in.

SCRUBBING

3-27

7400 MM428 (12--98)

SIDE SQUEEGEES

The side squeegees control water spray and

channel water into the path of the rear squeegee.

Check the side squeegees for damage and wear

daily. Replace the side squeegee blades

whenever they become damaged or lose their

shape or resilience. Replace the squeegee

deflectors whenever they become worn.

TO REPLACE SIDE SQUEEGEE BLADES

1. Raise the scrub head.

2. Shut off the engine and set the machine

parking brake.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Remove the cotter pin, clevis pin, deflector,

and the retainer bracket from the front of the

side squeegee.

4. Pull the squeegee blade out the front of the

squeegee frame.

5. Slide the new squeegee blade onto the

frame.

NOTE: Lubricating the squeegee frame where

the squeegee makes contact will make it easier to

install the squeegee blade.

6. Replace the retainer bracket, deflector,

clevis pin, and cotter pin.

7. Repeat for the side squeegee on the other

side of the scrub head.

00000

SCRUBBING

3-28 7400 MM428 (12--98)

TO REPLACE SIDE BRUSH SQUEEGEE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the side brush.

2. Shut off the engine and set the parking

brake.

FOR SAFETY: Before leaving or

servicing machine; stop on level

surface, set parking brake, turn off

machine and remove key.

3. Remove the side brush guard.

4. Remove the retainer clip from the end of the

squeegee.

5. Pull the squeegee blade out the front of the

squeegee frame.

6. Slide the new squeegee blade onto the

frame.

NOTE: Lubricating the squeegee frame where

the squeegee makes contact will make it easier to

install the squeegee blade.

7. Install the retainer clip on the end of the

squeegee.

8. Install the side brush guard.

SIDE BRUSH SKIRT

The side brush skirt is located behind the

squeegee blade. Check the skirt for wear and

damage every 100 hours of operation.

SCRUBBING

3-29

7400 MM428 (12--98)

VACUUM FAN

The vacuum fan, when activated, creates a

vacuum in the recovery tank. Water is pulled from

the rear squeegee to the recovery tank through a

vacuum hose. The vacuum fans impeller is driven

with a high speed hydraulic motor.

TO REMOVE VACUUM FAN

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Open the engine cover, engine side door,

and the front cover.

2. Loosen the hose clamp and remove the

vacuum hose leading from recovery tank to

the center of the vacuum fan housing.

3. Mark, disconnect, and plug the four

hydraulic hoses going to the vacuum fan

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

4. Remove three M10 hex screws, washers,

and nyloc nuts holding vacuum fan to

mounting brackets.

5. Remove the vacuum fan assembly from the

machine.

SCRUBBING

3-30 7400 MM428 (12--98)

TO INSTALL VACUUM FAN

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Position the vacuum fan assembly back in

the machine

2. Align the three mounting holes in the

vacuum fan housing with the three rubber

isolators in the mounting brackets. Reinstall

the three M10 hex screws, washers, and

nyloc nuts. Tighten to 18 -- 24 Nm

(13 -- 18 ft lb).

3. Reconnect the hydraulic hoses to the

vacuum fan motor. See schematic

in HYDRAULIC section.

4. Reinstall vacuum hose from recovery tank to

vacuum fan housing. Hand tighten clamps.

5. Start the engine and turn on the vacuum fan.

Check for leaks and proper operation.

SCRUBBING

3-31

7400 MM428 (12--98)

TO REPLACE VACUUM IMPELLER

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Remove the vacuum fan from the machine.

See TO REMOVE VACUUM FAN

instructions.

2. Place the vacuum fan assembly in a vice or

some other holding device.

3. Remove the six hex screws holding the front

housing to rear housing. Remove the front

housing.

NOTE: Mark the front housing in relation to the

rear housing so it is re--assembled correctly.

4. Remove crown nut on impeller shaft. Slide

impeller off shaft.

NOTE: Remove and save the key and any shims

that are on the motor shaft, under the impeller.

5. Install the shims, key, new fan impeller, and

crown nut. Tighten nut to 34 -- 47 Nm

(25 -- 35 ft lb).

NOTE: Be sure the square key is on the motor

shaft. Super gluing the key to the shaft helps keep

it in place when installing the impeller.

NOTE: Use a small amount of blue loctite 242 on

the motor shaft threads.

6. Reinstall the front housing on the rear

housing. Reinstall the six hex screws and

tighten to 22 -- 27 Nm (16 -- 20 ft lb).

NOTE: Tennant part no. 57543 plastic shims must

be used for proper fan to housing clearance.

Remove these shims after housing hardware has

been tightened.

7. Reinstall the vacuum fan assembly in the

machine. See TO INSTALL VACUUM FAN

instructions.

SCRUBBING

3-32 7400 MM428 (12--98)

ELECTRICAL

4-1

7400 MM428 (9--01)

CONTENTS

Page

INTRODUCTION 4-3.........................

BATTERY 4-4............................

TO REPLACE BATTERY 4-5............

INSTRUMENT PANEL 4-6.................

TO REPLACE INSTRUMENT PANEL 4-6.

TO DISASSEMBLE INSTRUMENT

PANEL 4-7.........................

TO REASSEMBLE INSTRUMENT

PANEL 4-8.........................

TO REPLACE MACHINE RELAY 4-9.....

TO REPLACE CIRCUIT BREAKER 4-10..

GAS/LPG ELECTRICAL

SCHEMATIC 4-11...................

GAS/LPG ELECTRICAL

SCHEMATIC 4-12...................

DIESEL ELECTRICAL SCHEMATIC 4-13.

DIESEL ELECTRICAL SCHEMATIC 4-14.

GAS/LPG WIRE HARNESS GROUP 4-15.

GAS/LPG WIRE HARNESS GROUP

(OPTIONS) 4-18....................

DIESEL WIRE HARNESS GROUP 4-19..

DIESEL WIRE HARNESS GROUP

(OPTIONS) 4-22....................

ELECTRICAL 4-11...........................

DIAGNOSTICS 4-23.....................

OPERATING MODES 4-24................

NORMAL MODE 4-25.................

SCRUB BUTTON 4-25..............

SQUEEGEE BUTTON 4-26.........

DETERGENT 4-27.................

EStBUTTON 4-27................

OVERFLOW FLOAT 4-27...........

MANUAL MODE 4-28.................

EStBUTTON 4-28................

SIDE BRUSH BUTTON 4-28........

SQUEEGEE BUTTON 4-28.........

ENGINE BUTTON 4-28.............

SCRUB BUTTON 4-28..............

DETERGENT BUTTON 4-28........

INPUT DISPLAY MODE 4-29...........

ERROR DISPLAY MODE 4-30..........

EStLED 4-30.....................

SIDE BRUSH LED 4-31.............

SQUEEGEE LED 4-31..............

SCRUB LED 4-32..................

DETERGENT LED 4-32.............

PRESSURE ADJUST MODE 4-33......

SCRUB BUTTON 4-33..............

RESET SCRUB PRESSURES 4-34.....

TROUBLESHOOTING 4-35...............

INSTRUMENT PANEL DOES NOT

POWER UP (SCHEMATIC) 4-36.....

INSTRUMENT PANEL DOES NOT

POWER UP (FLOW CHART) 4-37...

Page

SCRUB BRUSH WILL NOT TURN ON

AND/OR DOWN (SCHEMATIC) 4-38.

SCRUB BRUSH WILL NOT TURN ON

AND/OR DOWN (FLOW CHART) 4-39

SQUEEGEE AND VACUUM FAN NOT

TURNING ON AND GOING DOWN

(SCHEMATIC) 4-41..............

SQUEEGEE AND VACUUM FAN NOT

TURNING ON AND GOING DOWN

(FLOW CHART) 4-42............

SIDE BRUSH WILL NOT TURN ON AND

GO DOWN (SCHEMATIC) 4-44......

SIDE BRUSH WILL NOT TURN ON

ANDGODOWN(FLOWCHART) 4-45

WATER VALVES NOT OPERATING

(SCHEMATIC) 4-47................

WATER VALVES NOT OPERATING

(FLOW CHART) 4-48...............

HEAD LIGHTS WILL NOT TURN ON

(SCHEMATIC) 4-49.................

HEAD LIGHTS WILL NOT TURN ON

(FLOW CHART) 4-50...............

EStPUMP NOT WORKING

(SCHEMATIC) 4-51................

EStPUMP NOT WORKING

(FLOW CHART) 4-52...............

REVERSE LIGHT OR ALARM NOT

WORKING (SCHEMATIC) 4-54......

REVERSE LIGHT OR ALARM NOT

WORKING (FLOW CHART) 4-55.....

DETERGENT METERING PUMP IS NOT

OPERATING (SCHEMATIC) 4-57....

DETERGENT METERING PUMP IS NOT

OPERATING (FLOW CHART) 4-58...

ALTERNATOR / BATTERY WARNING

LIGHT STAYS ON WHEN ENGINE

IS RUNNING (SCHEMATIC) 4-59.

ALTERNATOR / BATTERY WARNING

LIGHT STAYS ON WHEN ENGINE

IS RUNNING (FLOW CHART) 4-60

ALTERNATOR / BATTERY WARNING

LIGHT WILL NOT TURN ON

(SCHEMATIC) 4-61..............

ALTERNATOR / BATTERY WARNING

LIGHT WILL NOT TURN ON

(FLOW CHART) 4-62............

ENGINE TEMPERATURE LIGHT WILL

NOT TURN ON OR OFF

(SCHEMATIC) 4-63..............

ENGINE TEMPERATURE LIGHT WILL

NOT TURN ON (FLOW CHART) 4-64

ENGINE TEMPERATURE LIGHT WILL

NOT TURN OFF (FLOW CHART) 4-64

ELECTRICAL

4-2 7400 MM428 (9--01)

Page

HYDRAULIC (HIGH) PRESSURE

INDICATOR LIGHT WILL NOT TURN

ON OR OFF (SCHEMATIC) 4-65..

HYDRAULIC (HIGH) PRESSURE

INDICATOR LIGHT WILL NOT TURN

ON (FLOW CHART) 4-66........

HYDRAULIC (HIGH) PRESSURE

INDICATOR LIGHT WILL NOT TURN

OFF (FLOW CHART) 4-66.......

ENGINE OIL PRESSURE WARNING

LIGHT WILL NOT TURN ON OR

OFF (SCHEMATIC) 4-67.........

ENGINE OIL PRESSURE WARNING

LIGHT WILL NOT TURN ON

(FLOW CHART) 4-68.............

ENGINE OIL PRESSURE WARNING

LIGHT WILL NOT TURN OFF

(FLOW CHART) 4-68.............

RECOVERY TANK FULL LIGHT WILL

NOT TURN ON OR OFF

(SCHEMATIC) 4-69...............

RECOVERY TANK FULL LIGHT WILL

NOT TURN ON (FLOW CHART) 4-70.

RECOVERY TANK FULL LIGHT WILL

NOT TURN OFF (FLOW CHART) 4-70

FUEL GAUGE (GAS AND DIESEL)

(SCHEMATIC) 4-71.................

FUEL GAUGE (GAS AND DIESEL)

(FLOW CHART) 4-72................

FUEL GAUGE (LPG) (SCHEMATIC) 4-73.

FUEL GAUGE (LPG) (FLOW CHART) 4-74

ELECTRICAL

4-3

7400 MM428 (12--98)

INTRODUCTION

The machine electrical system consists of the

battery, relays, instrument panels, and related

components. This section includes information on

these components and their troubleshooting.

ELECTRICAL

4-4 7400 MM428 (12--98)

BATTERY

The battery used in the machine is a low

maintenance battery. It has been constructed with

special materials and has extra electrolyte to

reduce or eliminate maintenance. Its design

reduces electrolyte loss and contamination. Do

not add water, remove the battery vent plugs, or

check the battery specific gravity. For specific

instructions, see the battery label.

Do not allow the battery to remain in discharged

condition for any time. Do not operate the

machine if the battery is in poor condition or

discharged beyond 80%, specific gravity below

1.120.

Periodically clean the top surface of the batteries

and the terminals, and check for loose

connections. Use a strong solution of baking

soda and water. Brush the solution sparingly over

the battery tops, terminals, and cable clamps. Do

not allow any baking soda solution to enter the

batteries. Use a wire brush to clean the terminal

posts and the cable connectors. After cleaning,

apply a coating of clear battery post protectant to

the terminals and the cable connectors. Keep the

tops of the batteries clean and dry.

Keep all metallic objects off the top of the

batteries, which may cause a short circuit.

Replace any worn or damaged wires.

The electrolyte level in regular non--sealed

batteries can be checked. The level must always

be above the battery plates. Never add acid to the

batteries, only distilled water. Keep the battery

caps on the batteries always except when adding

water or taking hydrometer readings.

FOR SAFETY: When Servicing Machine,

Avoid Contact With Battery Acid.

ELECTRICAL

4-5

7400 MM428 (12--98)

Using a hydrometer to measure the specific

gravity is a way to determine the charge level and

condition of the batteries. If one or more of the

battery cells test lower than the other battery cells

(0.050 or more), the cell is damaged, shorted, or

is about to fail.

NOTE: Do not take readings immediately after

adding distilled water. If the water and acid are not

thoroughly mixed, the readings may not be

accurate. Check the hydrometer readings against

the following chart to determine the remaining

battery charge level:

SPECIFIC GRAVITY BATTERY

at 27_C(80_F) CHARGE

1.260 -- 1.280 100% Charged

1.230 -- 1.250 75% Charged

1.200 -- 1.220 50% Charged

1.170 -- 1.190 25% Charged

1.110 -- 1.160 Discharged

NOTE: If the readings are taken when the battery

electrolyte is any temperature other than 27_C

(80_F), the reading must be temperature

corrected. Add or subtract to the specific gravity

reading 0.004, 4 points, for each 6_C(10_F)

above or below 27_C(80_F).

TO REPLACE BATTERY

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the seat support and engage the prop

rod.

2. Disconnect the negative then the positive

battery cables.

3. Remove the battery hold down bracket from

the machine.

4. Tilt the battery and lift it out of the machine.

5. Clean the cables and the posts on the new

battery and install back in the machine.

6. Reinstall the battery hold down bracket.

7. Reconnect the positive then the negative

battery cables and close the seat support.

ELECTRICAL

4-6 7400 MM428 (12--98)

INSTRUMENT PANEL

The instrument panel consists of a circuit board, a

touch panel, and a water/dust resistant plastic

enclosure. Its touch panel controls various

machine functions, while its indicator lights keep

the operator informed on machine performance.

TO REPLACE INSTRUMENT PANEL

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the seat support and engage the prop

rod.

2. Remove the battery cables from the battery.

3. Put the steering wheel in the lowest position.

4. Open the front cover on the machine.

5. Remove four M5 pan head screws holding

the instrument panel to the dash panel.

6. Pull the instrument panel back away from

machine.

7. Loosen the allen head screw in center of

wire harness plug. Disconnect the harness.

8. Remove instrument panel from machine.

9. Install the new instrument panel back on the

dash panel with the four M5 pan head

screws and washers. Hand tighten snug.

10. Push the main harness plug back in the

instrument panel.

NOTE: Slot in panel must line up with notch on

plug. Hand tighten the allen head screw.

11. Close the front cover.

12. Reconnect the battery cables and lower the

seat support.

13. Start the machine and check for proper

operation.

ELECTRICAL

4-7

7400 MM428 (12--98)

TO DISASSEMBLE INSTRUMENT PANEL

1. Remove panel from machine. See TO

REPLACE INSTRUMENT PANEL

instructions.

2. Place the instrument panel face down and

remove the twelve larger pan head screws

from the back.

3. The touch panel case can now be separated

from the outer case and new O-ring gasket

installed if necessary.

4. To disassemble the touch panel case further,

remove the four smaller pan head screws

from the center of case box.

5. Remove the case box from the circuit board

/ touch panel assembly.

6. The O--ring and connector gaskets can now

be replaced in the case box if necessary.

7. Remove the eight pan head screws, unplug

the flat connector and ground strap, remove

the touch panel from the circuit board.

8. Any burned-out lamps can now be changed

by turning them 1/4 turn counterclockwise

and lifting out.

9. To replace the hour meter, unplug the two

wires and remove the two pan head screws.

ELECTRICAL

4-8 7400 MM428 (12--98)

TO REASSEMBLE INSTRUMENT PANEL

1. Position the circuit board over the touch

panel. Feed the flat connector from panel

through the slot in board, plug it in and

reconnect the ground strap.

2. Reinstall the eight pan head screws and

lightly hand tighten.

3. Turn the circuit board assembly over and

place it back in the case box.

4. Reinstall the four smaller pan head screws

in center of case box. Lightly hand tighten.

5. Reinstall the touch panel case on the outer

case.

6. Reinstall the twelve pan head screws and

lightly hand tighten.

7. The instrument panel is now ready to be

reinstalled in the machine. See TO

REPLACE INSTRUMENT PANEL

instructions.

ELECTRICAL

4-9

7400 MM428 (12--98)

TO REPLACE MACHINE RELAY

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the seat support and engage the prop

rod.

2. Remove the battery cables from the battery.

3. Open the front cover on the machine.

4. Locate the relays at the front of the

operators compartment, near the hydraulic

steering motor.

5. Lift up on the relay to harness locking tab.

6. Pull the harness plug out of the relay.

7. Remove the pan screw holding the relay to

the operators compartment. Remove and

discard the old relay.

8. Position the new relay on the operators

compartment.

9. Reinstall the pan screw holding the relay to

the operators compartment.

10. Reconnect the harness plug in the relay.

See schematic in the ELECTRICAL section.

11. Reconnect the battery cables to the battery.

12. Lower the seat support.

13. Close the front cover on the machine.

14. Start and operate the machine, checking for

proper operation.

ELECTRICAL

4-10 7400 MM428 (12--98)

TO REPLACE CIRCUIT BREAKER

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the seat support and engage the prop

rod.

2. Remove the battery cables from the battery.

3. Open the front cover on the machine.

4. Locate the circuit breakers at the front of the

operators compartment, near the hydraulic

steering motor.

5. Remove and retain the rubber boot on the

front of the circuit breaker

6. Disconnect the electrical wires on the back

of the circuit breaker.

7. Remove the steel retaining ring holding the

circuit breaker to the dash panel. Remove

the circuit breaker.

8. Position the new circuit breaker in the

mounting hole on the dash panel.

9. Install the retaining ring on the new circuit

breaker. Push the ring on all the way to the

bottom of the circuit breaker.

10. Reconnect the wires to the back of the

circuit breaker. See schematic in the

ELECTRICAL section.

11. Reconnect the battery cables to the battery.

12. Lower the seat support.

13. Close the front cover on the machine.

14. Start and operate the machine, checking for

proper operation.

ELECTRICAL

4-11

7400 MM428 (6--01)

18A/ORA

1E/RED

1/RED

15B/BLU

13E/BLK

19B/BLU

72C/YEL

71C/YEL

72C/YEL

23C/GRY

PIN 20

TIED TO ENG.

OIL PRESS.

PIN 9

SCRUB BR.

MUST BE ON

5 SEC. DELAY

ES PUMP RUNS

30 SEC.

5 SEC. DELAY

1MIN.TOVAC

FAN SHUT--OFF

42B/YEL

42A/YEL42/YEL

56/ORA

19A/BLU

13R/BLK

13M/BLK

13K/BLK

13D/BLK

13G/BLK

23C/GRY

23B/GRY 23/GRY

27/PUR

26/BRN

58/BLU

60/GRN

18T/ORA

RECOVERY

TANK

SOLUTION

TANK

S--18 N.C.H.O.

S--17 N.O.H.C.

13F/BLK

72B/GRY

18U/ORA

71B/YEL

ELEC.

SPARK

CONT.

COOLANT TEMP.

SENSOR

67/ORA

10K OHMS

VAR. RELUCTANCE

SENSOR

64/BRN

65/BLU

66/GRN

68/BRN T

13PP/BLK

70/GRN

PLUGS

13N/BLK

FILTER SWITCH

S--14

HYDRAULIC

LIGHTS

85 86 LP CLOSES BELOW

40 PSI

REVERSE

85 86

83/BRN

10/GRY

15/BLU

CB--1

15A

36/GRN

35/BRN

13H/BLK

14/GRN

18A/ORA

N.C.H.O.

GAS--DIESEL

13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

STARTER RELAY

S--6

18A/

ORA

18A/

ORA

71C/YEL

18C/ORA

18/ORA

8730

FLOW SWITCH

15/

BLU

M4 8685

28/YEL

M5 57/GRN

5.0A

S--15

23A/GRY

ES PUMP

MTR

DETERGENT METERING

85 86

REVERSE

RECOVERY TANK

S--8

S--1

M322/

YEL

8685 M3

1E/

RED

CB--6

19/BLU

ORA

IGNITION

SWITCH

S--3

CB--5

43/BLU

13L/BLK

13J/BLK

55A MAX.

CHARGE

1C/RED

1D/RED

2/ORA

1B/RED

5/YEL

18D/ORA

12V

540 C.C.A.

20A/BLU

20/BLU

10/GRY

4/YEL

84/GRN

86/PUR

FEDC

CLOSES AT225

°F

ELECTRONIC

INSTRUMENT

PANEL

COOLANT TEMP

SENDER

FUEL SENDER

SE--1

SE--2

HORN BUTTON

15A

HORN

BATT.

ACC

START

SENSE

GOV

CONTROL

THROTTLE

ACTUATOR

13A/BLK

STARTER MOTOR

13/BLK

TTER

ALTERNATOR

GND

OUT

1A/RED

STARTER RELAY

M1 MTR

SHEET 1

GAS/LPG ELECTRICAL SCHEMATIC

ELECTRICAL

4-12 7400 MM428 (6--01)

SHEET 2

GAS/LPG ELECTRICAL SCHEMATIC

ELECTRICAL

4-13

7400 MM428 (6--01)

8/GRN

FU--1

40A

13Q/BLK

GLOW PLUGS

MAGNETIC

PICKUP

7/YEL

72C/GRY

71C/YEL

84/GRN

86/PUR

18C/ORA

THROTTLE

ACTUATOR

23C/GRY

PIN 20

TIED TO ENG.

OIL PRESS.

PIN 9

SCRUB BR.

MUST BE ON

5 SEC. DELAY

ES PUMP RUNS

30 SEC.

5 SEC. DELAY

1MIN.TOVAC

FAN SHUT--OFF

42A/YEL42/YEL

56/ORA

19A/BLU

13R/BLK

13K/BLK

13D/BLK

13G/BLK

23C/GRY

23B/GRY 23/GRY

27/PUR

26/BRN

58/BLU

60/GRN

RECOVERY

TANK

SOLUTION

TANK

S--18 N.C.H.O.

S--17 N.O.H.C.

13N/BLK

FILTER SWITCH

S--14

HYDRAULIC

LIGHTS

85 86

REVERSE

85 86

83/BRN

10/GRY

15/BLU

15A

CB--1

15A

CB--5

15A

CB--5

15A

36/GRN

35/BRN

13H/BLK

14/GRN

18A/ORA

N.C.H.O.

GAS--DIESEL

13P/BLK

13B/BLK

S--4 OIL SWITCH15A/BLU

FUEL PUMP

10A/GRY

STARTER RELAY

18A/

ORA

18A/

ORA

18/ORA

8730

FLOW SWITCH

15/

BLU

M4 8685

28/YEL

M5 57/GRN

5.0A

S--15

23A/GRY

ES PUMP

MTR

DETERGENT METERING

85 86

REVERSE

RECOVERY TANK

S--8

S--1

22/

YEL

8685 M3

1E/

RED CB--6

19/BLU

ORA

IGNITION

SWITCH

S--3

CB--5

43/BLU

13L/BLK

13J/BLK

55A MAX.

CHARGE

1C/RED

1D/RED

2/ORA

1B/RED

5/YEL

12V

540 C.C.A.

20A/BLU

20/BLU

10/GRY

4/YEL

FEDC

CLOSES AT

225

ELECTRONIC

INSTRUMENT

PANEL

COOLANT TEMP

SENDER

FUEL SENDER

SE--1

SE--2

HORN BUTTON

15A

HORN

BATT.

ACC

START

SENSE

GOV

CONTROL

13A/BLK

STARTER MOTOR

13/BLK

BATTERY

ALTERNATOR

GND

OUT

1A/RED

STARTER RELAY

1/RED MTR

SHEET 3

DIESEL ELECTRICAL SCHEMATIC

ELECTRICAL

4-14 7400 MM428 (6--01)

SHEET 4

DIESEL ELECTRICAL SCHEMATIC

ELECTRICAL

4-15

7400 MM428 (6--01)

13H/BLK

96/GRY

96B/GRY

46/BRN

46C/BRN

BRN

BLK

RED

62E/BRN

13II/BLK

89B/ORA

13J/BLK

13M/BLK

13F/BLK

13N/BLK

13TT/BLK

13P/BLK

13B/BLK

1D/RED

1A/RED

1C/RED

CIRCUIT 2

CIRCUIT 1

25D/GRY

25A/GRY

46C/BRN WATER

VALV E

CONTROL

42A/YEL

VIEW B--B

WATER CONTROL

SWITCH

36/GRN

13R/BLK

43/BLU

RED

GRN

BLK

BRN

BLK

RED

MAIN PANEL

96/GRY

95/BLU

5/YEL

4/YEL

SIDE BRUSH

VALV E LOW

OPTION

SOLUTION

SWITCHES

OPTION

R.H. TAIL--LIGHT

SEE MAIN SCRUB VALVE

HYD. FILTER SWITCH

OPTIONS

REC TANK -- INNER SWITCH

NO C

62D/BRN

13HH/BLK

89A/ORA

BACK--UP

ALARM

ES PUMP

AUTO FILL

ROT. LIGHT

SEE OPTIONS

DETERGENT PUMP

28/YEL

13J/BLK

13K/BLK

13R/BLK

13F/BLK

18C/ORA

71C/YEL

CBA

10/GRY

42/YEL

62A/YEL

CBA

ABC

1E/RED

HORN

1/RED

BATTERY

STARTER

TO MAIN

HARNESS

85/BLU

83/BRN

84/GRN

86/PUR

72C/YEL 18D/ORA

13E/BLK

71C/YEL 1D/RED

20D/BLU

20/BLU

10A/GRY

10/GRY

VIEW C--C

GOVERNOR

CONTROL VIEW F--F

KEY SWITCH

ALTERNATOR

WATER

TEMPERATURE

SENDER

13A/BLK

SEE

OPTIONS

FUEL

SENDER

42A/YEL

13L/BLK

1/RED

BATTERY

GAS AND DIESEL

LOCATION

ENGINE

13/BLK

13P/BLK

14/GRN

FUEL PUMP

HORN

SWITCH

15B/BLU

13B/BLK

86/PUR

84/GRN

13M/BLK

D.I.S. ENGINE

HARNESS

ACTUATOR

OIL

PRESSURE

SWITCH

L.P.

SWITCH

72C/YEL

13X/BLK

13Y/BLK

13DD/BLK

13G/BLK

GOVERNOR

CONTROL

L.H. HEADLIGHT

62B/YEL

62A/YEL

13DD/BLK

13CC/BLK

R.H. HEADLIGHT

62/YEL

L.H. TAIL--LIGHT

RELAYS

LOWHIGH

REVERSE

FLOW

SWITCH

SIDE BRUSH VALVE

OPTION

DIODE

BRAKE SWITCH

OPTION

CIRCUIT BREAKERS

WATER CONTROL

SWITCH

SHEET 5

GAS/LPG WIRE HARNESS GROUP

ELECTRICAL

4-16 7400 MM428 (6--01)

18U/BLK

87A

VIEW A--A

RELAYS

M2 FUEL PUMP

M3 INSTRUMENT PANEL

M4 HYD. SOLENOIDS

M5 ES PUMP

M6 HEADLIGHTS

M7 REVERSE

21B/GRY

25/GRY

72C/YEL

71C/YEL

70/GRN

13PP/BLK

18T/ORA

68/BRN

67/ORA

66/GRN

65/BLU

VIEW G--G

UNIVERSAL

ELECTRONIC

SPARK CONTROL

UNIVERSAL

ELECTRONIC

SPARK CONTROL

66/GRN

65/BLU

VARI BL E

RELUCTANCE

SENSOR

70/GRN

64/BRN

COOLANT

SENSOR

71B/YEL

72B/GRY

DISTRIBUTORLESS

IGNITION

COIL

D.I.S. ENGINE

HARNESS TO MAIN

HARNESS

13F/BLK

18C/ORA

71C/YEL

72C/YEL

1F/RED

92/PUR

18/ORA

18C/ORA

20/BLU

4/YEL

65/GRY

65A/GRY

22/YEL

4A/YEL

1C/RED

59/BRN

59A/BRN

20C/BLU

CIRCUIT

BREAKERS

CB--1 IGNITION

CB--2 ES PUMP

CB--3 HEADLIGHTS

CB--4 BACK--UP ALARM

CB--5 HORN

CB--6 INSTRUMENT PANEL (5.0A)

CB--7 SCRUB SOLENOIDS

CB--8 SIDE BRUSH SOLENOIDS AND

WATER VALVES

CB--3

MAIN

HARNESS

CB--1CB--2CB--4

CB--5CB--6CB--7CB--8

20B/BLU

20A/BLU

24/PUR

25A/GRY

1E/RED

21A/GRY

21/GRY

DIODE

ASSY

19B/BLU

13D/BLK

10A/GRY

92/PUR

M5 M6 M7M2 M3 M4

93/ORA62/YEL

58/BLU19A/BLK

65/GRY

57/GRN

66/BRN

59/BRN

60/GRN

14/GRN

15A/BLU

18A/ORA

22/YEL

19/BLU

18A/ORA

23B/GRY

1F/RED

18A/ORA

21/GRY

23C/GRY 23C/GRY 23C/GRY

2345 7

MAIN

HARNESS

SECTION B--B

85 COIL+

86 COIL --

30 COMMON CONTACT

87 N.O. CONTACT

87A N.C. CONTACT

SHEET 6

GAS/LPG WIRE HARNESS GROUP

ELECTRICAL

4-17

7400 MM428 (6--01)

MAIN INSTRUMENT

PANEL SOCKET

REAR VIEW

SV2

24B/PUR

13 7

24B/PUR

48/GRY

47/BRN

24B/PUR

45/GRY

24B/PUR

46A/BRN

25C/GRY

46A/BRN

SV7 46A/BRN

24B/PUR

SCRUB VALVE

BLOCK

MAIN

HARNESS

51C/PUR

SV5

SV1SV6

SV4

SV3

HYDRAULIC SOLENOID VALVES

SV--1 SCRUB BRUSH ON

SV--2 VACUUM FAN ON

SV--3 SQUEEGEE DOWN

SV--4 DOWN PRESS. PROPORTIONAL VALVE

SV--5 SCRUB BRUSH DOWN

SV--6 SIDE BRUSH ON

SV--7 SCRUB BRUSH UP -- HOLD

58/BLU

83/BRN

1A/RED

21B/GRY

13S/BLK

13T/BLK

13U/BLK

45/GRY

60/GRN

46/BRN

48/GRY

15/BLU

2/ORA

42/ORA

51/PUR

47/BRN

28/YEL

56/YEL

36/GRN

35/BRN

52/YEL

43/BLU

57/GRN

26/BRN

23/GRY

13A/BLK

1B/RED

2/ORA

EXC

CONN. A.SOC. NO.

CONNECTOR WIRIN

MANDO

ALTERNATOR

60559

MAIN

HARNESS

ENGINE

BLOCK

SHEET 7

GAS/LPG WIRE HARNESS GROUP

ELECTRICAL

4-18 7400 MM428 (6--01)

SHEET 8

GAS/LPG WIRE HARNESS GROUP (OPTIONS)

ELECTRICAL

4-19

7400 MM428 (6--01)

13DD/BLK

43/BLU 1D/RED

1C/RED

1A/RED

62A/YEL

BRN

BLK

RED

62E/BRN

13II/BLK

89B/ORA

WATER CONTROL

SWITCH

CIRCUIT 2

CIRCUIT 1

25A/GRY

MAGNETIC

PICK--UP

13Y/BLK 72E/GRN

GLOW PLUGS

8/GRN

7/YEL

8/GRN

7A/YEL

7/YEL

MAIN

HARNESS 1D/RED

20D/BLU

20/BLU

10A/GRY

10/GRY

25D/GRY

E H

46C/BRN

13H/BLK

WATER

VALV E CONTROL

VIEW B--B

WATER CONTROL

SWITCH

36/GRN

13R/BLK

RED

GRN

BLK

BRN

BLK

RED

MAIN PANEL

96/GRY

25D/GRY

95/BLU

5/YEL

96/GRY

96B/GRY

46/BRN

46C/BRN

5/YEL

4/YEL

SIDE BRUSH

VALV E LOW

OPTION

SOLUTION SWITCHES

R.H. TAIL--LIGHT

SEE MAIN SCRUB VALVE

HYD. FILTER SWITCH

OPTIONS

REC TANK -- INNER SWITCH

NO C

62D/BRN

13HH/BLK

89A/ORA

BACK--UP

ALARM ES PUMP

AUTO FILL

ROT. LIGHT

SEE OPTIONS

SHEET 12

DETERGENT PUMP

28/YEL

13J/BLK

13K/BLK

13M/BLK

13J/BLK

13R/BLK

10/GRY

42/YEL

62A/YEL

CBA

ABC

1E/RED

HORN

1/RED

BATTERY

STARTER

85/BLU

83/BRN

84/GRN

86/PUR

72C/YEL 18D/ORA

13E/BLK

71C/YEL

VIEW C--C

GOVERNOR CONTROL

VIEW F--F

KEY SWITCH

ALTERNATOR

WATER

TEMPERATURE

SENDER

13A/BLK

FUEL

SENDER

42A/YEL

13L/BLK

1/RED

BATTERY

GAS AND DIESEL

LOCATION

ENGINE

13/BLK

13P/BLK

14/GRN

FUEL PUMP

HORN

SWITCH

15B/BLU

13B/BLK

86/PUR

84/GRN

ACTUATOR

OIL

PRESSURE

SWITCH

13N/BLK

13X/BLK

13TT/BLK

13P/BLK

13B/BLK

13Y/BLK

13G/BLK

GOVERNOR

CONTROL

L.H. HEADLIGHT

62B/YEL

13DD/BLK

13CC/BLK

R.H. HEADLIGHT

62/YEL

L.H. TAIL--LIGHT

RELAYS

LOW

HIGH

REVERSE

FLOW

SWITCH

SIDE BRUSH

VALV E

OPTION

DIODE

BRAKE SWITCH

OPTION

CIRCUIT BREAKERS

A B

SHEET 9

DIESEL WIRE HARNESS GROUP

ELECTRICAL

4-20 7400 MM428 (6--01)

87A

21B/GRY

25/GRY

1F/RED

92/PUR

18/ORA

18C/ORA

20/BLU

4/YEL

65/GRY

65A/GRY

22/YEL

4A/YEL

1C/RED

59/BRN

59A/BRN

20C/BLU

CIRCUIT

BREAKERS

CB--1 IGNITION

CB--2 ES PUMP

CB--3 HEADLIGHTS

CB--4 BACK--UP ALARM

CB--5 HORN

CB--6 INSTRUMENT PANEL (5.0A)

CB--7 SCRUB SOLENOIDS

CB--8 SIDE BRUSH SOLENOIDS AND

WATER VALVES

CB--3

MAIN

HARNESS

CB--1CB--2CB--4

CB--5CB--6CB--7CB--8

20B/BLU

20A/BLU

24/PUR

25A/GRY

1E/RED

21A/GRY

21/GRY

VIEW A--A

ROTATED

DIODE

ASSY

19B/BLU

13D/BLK

RELAYS

M2 FUEL PUMP

M3 INSTRUMENT PANEL

M4 HYD. SOLENOIDS

M5 ES PUMP

M6 HEADLIGHTS

M7 REVERSE

10A/GRY

92/PUR

M5 M6 M7M2 M3 M4

93/ORA62/YEL

58/BLU

19A/BLK

65/GRY

57/GRN

66/BRN

59/BRN

60/GRN

14/GRN

15A/BLU

18A/ORA

22/YEL

19/BLU

18A/ORA

23B/GRY

1F/RED

18A/ORA

21/GRY

23C/GRY 23C/GRY 23C/GRY

234567

MAIN

HARNESS

SECTION B--B

85 COIL+

86 COIL --

30 COMMON CONTACT

87 N.O. CONTACT

87A N.C. CONTACT

SHEET 10

DIESEL WIRE HARNESS GROUP

ELECTRICAL

4-21

7400 MM428 (6--01)

SV2

24B/PUR

48/GRY

47/BRN

24B/PUR

45/GRY

24B/PUR

46A/BRN

25C/GRY

46A/BRN

SV7 46A/BRN

24B/PUR

SCRUB VALVE

BLOCK

MAIN

HARNESS

51C/PUR

SV5

SV1SV6

SV4

SV3

HYDRAULIC SOLENOID VALVES

SV--1 SCRUB BRUSH ON

SV--2 VACUUM FAN ON

SV--3 SQUEEGEE DOWN

SV--4 DOWN PRESS. PROPORTIONAL VALVE

SV--5 SCRUB BRUSH DOWN

SV--6 SIDE BRUSH ON

SV--7 SCRUB BRUSH UP -- HOLD

MAIN INSTRUMENT

PANEL SOCKET

REAR VIEW

13 7

58/BLU

83/BRN

1A/RED

21B/GRY

13S/BLK

13T/BLK

13U/BLK

45/GRY

60/GRN

46/BRN

48/GRY

15/BLU

2/ORA

42/ORA

51/PUR

47/BRN

28/YEL

56/YEL

36/GRN

35/BRN

52/YEL

43/BLU

57/GRN

26/BRN

23/GRY

13A/BLK

1B/RED

2/ORA

EXC

CONN. A.

SOC. NO.

CONNECTOR WIRING

MANDO

ALTERNATOR

60559

MAIN

HARNESS

ENGINE

BLOCK

SHEET 11

DIESEL WIRE HARNESS GROUP

ELECTRICAL

4-22 7400 MM428 (6--01)

13DD/BLK

43/BLU 1D/RED

1C/RED

1A/RED

62A/YEL

BRN

BLK

RED

62E/BRN

13II/BLK

89B/ORA

WATER CONTROL

SWITCH

CIRCUIT 2

CIRCUIT 1

25A/GRY

MAGNETIC

PICK--UP

13Y/BLK 72E/GRN

GLOW PLUGS

8/GRN

7/YEL

8/GRN

7A/YEL

7/YEL

MAIN

HARNESS 1D/RED

20D/BLU

20/BLU

10A/GRY

10/GRY

25D/GRY

E H

46C/BRN

13H/BLK

WATER

VALV E CONTROL

VIEW B--B

WATER CONTROL

SWITCH

36/GRN

13R/BLK

RED

GRN

BLK

BRN

BLK

RED

MAIN PANEL

96/GRY

25D/GRY

95/BLU

5/YEL

96/GRY

96B/GRY

46/BRN

46C/BRN

5/YEL

4/YEL

SIDE BRUSH

VALV E LOW

OPTION

SOLUTION SWITCHES

R.H. TAIL--LIGHT

SEE MAIN SCRUB VALVE

HYD. FILTER SWITCH

OPTIONS

REC TANK -- INNER SWITCH

NO C

62D/BRN

13HH/BLK

89A/ORA

BACK--UP

ALARM ES PUMP

AUTO FILL

ROT. LIGHT

SEE OPTIONS

SHEET 12

DETERGENT PUMP

28/YEL

13J/BLK

13K/BLK

13M/BLK

13J/BLK

13R/BLK

10/GRY

42/YEL

62A/YEL

CBA

ABC

1E/RED

HORN

1/RED

BATTERY

STARTER

85/BLU

83/BRN

84/GRN

86/PUR

72C/YEL 18D/ORA

13E/BLK

71C/YEL

VIEW C--C

GOVERNOR CONTROL

VIEW F--F

KEY SWITCH

ALTERNATOR

WATER

TEMPERATURE

SENDER

13A/BLK

FUEL

SENDER

42A/YEL

13L/BLK

1/RED

BATTERY

GAS AND DIESEL

LOCATION

ENGINE

13/BLK

13P/BLK

14/GRN

FUEL PUMP

HORN

SWITCH

15B/BLU

13B/BLK

86/PUR

84/GRN

ACTUATOR

OIL

PRESSURE

SWITCH

13N/BLK

13X/BLK

13TT/BLK

13P/BLK

13B/BLK

13Y/BLK

13G/BLK

GOVERNOR

CONTROL

L.H. HEADLIGHT

62B/YEL

13DD/BLK

13CC/BLK

R.H. HEADLIGHT

62/YEL

L.H. TAIL--LIGHT

RELAYS

LOW

HIGH

REVERSE

FLOW

SWITCH

SIDE BRUSH

VALV E

OPTION

DIODE

BRAKE SWITCH

OPTION

CIRCUIT BREAKERS

A B

SHEET 12

DIESEL WIRE HARNESS GROUP (OPTIONS)

ELECTRICAL

4-23

7400 MM428 (12--98)

DIAGNOSTICS

The Model 7400 has an on--board diagnostic

system. Each time the control board is powered

up, it performs a self test. If the self test passes,

the “OK” light is illuminated.

This trouble shooting section describes the

different operating modes that are available, how

to enter that mode, and a detail description of how

that mode works.

ELECTRICAL

4-24 7400 MM428 (12--98)

OPERATING MODES

The Model 7400 has 6 different operating modes.

The machine operator can access each mode by

pressing various buttons on the control panel,

holding them, and turning on the key. The

common operating modes are detailed in the

following charts.

Operating Modes Entry Sequence

(how to activate)

Normal Mode;Normal operation.

More info pages 4--25 thru 4--27

Default (when key is turned on)

Manual Mode; Manually operate discrete

functions without interlocks.

More info page 4--28

1. Push and hold the ES button

2. Turn on the key

3. Hold the ES button until the maintenance light

comes on.

4. Release the ES button

Input Display Mode; Display the state of floats,

limit switches, and sensors.

More info page 4--29

1. Push and hold the Squeegee button

2. Turn on the key

3. Hold the Squeegee button until the maintenance

light comes on.

4. Release the Squeegee button

Error Display Mode; Display the cause of a

self--test failure.

More info pages 4--30 thru 4--32

1. Push and hold the Detergent button

2. Turn on the key

3. Hold the Detergent button until the maintenance

light comes on.

4. Release the Detergent button

Pressure Adjust Mode; Adjust the pressure

levels for the three down pressure settings.

More info page 4--33

1. Push and hold the Side Brush button

2. Turn on the key

3. Hold the Side Brush button until the

maintenance light comes on.

4. Release the Side Brush button

Reset Scrub Pressures; Return the down

pressure settings to the factory defaults.

More info page 4--34

1. Push and hold the Scrub button

2. Turn on the key

3. Hold the scrub button

4. Wait for the maintenance light

5. While holding the Scrub button, press and hold

the Side Brush button

6. Wait for the maintenance light to go out

7. Release the Scrub and Side Brush buttons

8. Turn the key off

9. Restart the machine

ELECTRICAL

4-25

7400 MM428 (12--98)

Operating Mode Entry Sequence

(how to activate)

Normal Mode;Normal operation. Default (when key is turned on)

NORMAL MODE

The purpose of the normal mode is for the general

operation of the machine. The machine will

normally start in this mode. What follows is a brief

description of each of the operations in the normal

mode.

SCRUB BUTTON

The purpose of the scrub button is to turn the

scrubbing operations on and off and adjust the

scrubbing down pressure. Pressing the scrub

button while the scrubbing operation is currently

inactive will initiate the following actions:

1. The engine speed will be set to high.

2. If the machine is not in reverse, the main

brushes will turn on and lower. The down

pressure setting will be the same used

during the last scrub cycle. The solution will

flow at the high or low rate according to the

water position switch.

3. If the machine is in reverse, the brushes will

stay up until reverse is no longer sensed.

4. If the side brush LED is on, the side brush will

turn on and lower. The down pressure

setting will be the same used during the last

scrub cycle.

5. The vacuum fan will turn on.

6. If the machine is not in reverse, the squeegee

will lower.

7. If the machine is in reverse, the squeegee will

stay up until reverse is no longer sensed.

8. If any of the detergent LED’s are active, the

water valves are turned on, and the machine

is not in reverse, the detergent pump will

run. The detergent pump will run at its slow

rate if one LED is on. The detergent pump

will run at its fast rate if two LED’s are on.

ELECTRICAL

4-26 7400 MM428 (12--98)

SCRUB BUTTON (continued)

If the operator pushes and holds the scrub button,

the pressure settings will begin to scroll. The

pressure settings displayed after releasing the

scrub button will become the new default down

pressure setting.

If the scrub function was active and the operator

pushes, then releases the scrub button, the

following actions will take place:

1. The main brushes will turn off and rise.

2. The side brush will turn off and rise.

3. The solution flow will turn off.

4. The detergent pump will turn off.

5. A delay will pass, and then the squeegee will

rise.

6. Another small delay will pass and the vacuum

fan will turn off.

SQUEEGEE BUTTON

Pressing the squeegee button will start or stop the

water pickup operation. If the operator presses

the squeegee button while the squeegee LED is

currently not illuminated will cause the following

actions:

1. The squeegee LED will be illuminated.

2. The squeegee will drop and the vacuum fan

will turn on, if the machine is not in reverse.

If the machine goes into reverse while the

squeegee is active, the squeegee will rise.

Pressing the squeegee button while the squeegee

LED is on will cause the following actions:

1. The squeegee LED will turn off.

2. The squeegee will raise.

3. There will be a 30 second delay.

4. The vacuum fan will turn off.

ELECTRICAL

4-27

7400 MM428 (12--98)

DETERGENT

Pressing the detergent button will cause the

detergent display to scroll through its three

modes. The detergent pump will run only if the

main scrub brushes are active and the solution

switch is on.

DOff (all LED’s off) -- detergent pump off.

DLow (left LED is on) -- detergent pump on low.

DHigh (both LED’s are on) -- detergent pump

on high.

EStBUTTON

Pressing the EStbutton will enable or disable

the EStsystem. The EStsystem will draw

water from the recovery tank, through a filter and

pump it into the solution tank. If the operator has

turned on the EStsystem, and the recovery tank

EStfloat reads a full tank, the EStpump will

begin to run. The EStpump will continue to run

for about 30 seconds after the EStfloat

becomes uncovered.

OVERFLOW FLOAT

In order for the recovery tank float to become

active, it must be consistently in the up position

for at least 10 seconds. If the scrub or vacuum fan

are active and the tank full float becomes active,

the following actions will occur:

1. The overflow light will begin to blink.

2. A one minute delay will pass.

3. The overflow light will stop blinking and stay

on.

4. The Scrub and Squeegee functions will be

canceled.

ELECTRICAL

4-28 7400 MM428 (12--98)

Operating Mode Entry Sequence

(how to activate)

Manual Mode; Manually operate discrete

functions without interlocks.

1. Push and hold the EStbutton

2. Turn on the key

3. Hold the EStbutton until the maintenance

light comes on.

4. Release the EStbutton

MANUAL MODE

The purpose of the manual mode is to allow the

operator to exercise individual functions on the

machine.

NOTE: This mode disregards the effects of

various interlocks. Do not scrub with the

machine in this mode.

FOR SAFETY: When Servicing Machine,

AvoidMovingParts.DoNotWear

Loose Jackets, Shirts, Or Sleeves.

After entering the Manual Mode, the control

buttons assume the following functions:

EStBUTTON

Pressing the EStbutton will toggle the ESt

pump on or off. In the on position, the EStpump

will run regardless of the state of the floats.

SIDE BRUSH BUTTON

Pressing the Side Brush button will turn on and

lower the side brush. If the main brush is off, the

side brush will use the low pressure setting.

SQUEEGEE BUTTON

Pressing the Squeegee button will turn on the

vacuum fan and lower the squeegee. Reverse is

ignored.

ENGINE BUTTON

Pressing the Engine button will toggle the engine

between high and low speed.

SCRUB BUTTON

Pressing the Scrub button will turn on and lower

the main scrub head. Holding the Scrub button

while scrub is active will cause the down pressure

to scroll.

DETERGENT BUTTON

Pressing the Detergent button will cause the

detergent LED’s to scroll. If no LED’s are on, the

detergent pump will be off. If one LED is

illuminated, the detergent pump will run in low

speed. If both LED’s are on, the detergent pump

will run in high speed.

ELECTRICAL

4-29

7400 MM428 (12--98)

Operating Mode Entry Sequence

(how to activate)

Input Display Mode; Display the state of floats,

limit switches, and sensors.

1. Push and hold the Squeegee button

2. Turn on the key

3. Hold the Squeegee button until the maintenance

light comes on.

4. Release the Squeegee button

INPUT DISPLAY MODE

In this mode, the operator can observe whether or

not inputs to the panel are operating as intended.

In the Input Display Mode, the segments of the

gas gauge display the state of each input. If an

input is open, the controller turns off the segment

associated with that input. If an input is shorted to

ground, the controller turns on the segment

associated with that input.

The operation of the Input Display Mode is as

follows:

DSEGMENT 0 -- Rightmost segment of the

gas gauge. This segment displays the state

of the ES float. This segment will illuminate

when this input is shorted to ground.

DSEGMENT 1 -- Second segment from the

right of the gas gauge. This segment

displays the state of the recovery tank float.

This segment will be illuminated when this

input is shorted to ground.

DSEGMENT 2 -- Third segment from the right

of the gas gauge. This segment displays the

state of the reverse input. This segment will

be illuminated when this input is shorted to

ground.

DSEGMENT 3 -- Forth segment from the right

of the gas gauge. This segment displays the

state of the forward input. This segment will

be illuminated when this input is shorted to

ground.

DENGINE TEMPERATURE LIGHT -- In the

Input Display Mode, the engine temperature

light will blink until the engine reaches

operating temperature.

ELECTRICAL

4-30 7400 MM428 (12--98)

Operating Mode Entry Sequence

(how to activate)

Error Display Mode; Display the cause of a

self--test failure.

1. Push and hold the Detergent button

2. Turn on the key

3. Hold the Detergent button until the maintenance

light comes on.

4. Release the Detergent button

ERROR DISPLAY MODE

Each time the operator starts the machine, the

panel will run a self test on each output. If the

panel passes the diagnostic, the “OK” indicator is

illuminated. If the panel fails, a code is stored in a

non volatile (preserved even after power down)

memory. If the machine passes the diagnostic on

the next startup cycle, the panel preserves the

last failed code. In the Error Display Mode, the

operator can obtain the error code stored after the

last startup diagnostic failure. When the machine

is in this mode, the LED’s on the operators panel

will indicate which system experienced the failure.

If the operator pushes the button associated with

an illuminated LED, segments on the gas gauge

will indicate which output failed and what type of

failure occurred.

The operation of the Error Display Mode is as

follows:

EStLED

Problem with the EStoutput. If the operator

pushes the headlight button in this mode, the

panel will display one of the following codes:

DSEGMENT 0 -- Rightmost segment of the gas

gauge. This segment would indicate that the

output was shorted to ground when the

controller was expecting it to be open.

DSEGMENT 0, 1 -- First and second segments

from the right of the gas gauge. These

segments would indicate that the output was

open when the controller was trying to short

it to ground.

ELECTRICAL

4-31

7400 MM428 (12--98)

SIDE BRUSH LED

Problem with the side brush or side brush

actuator outputs. If the operator pushes the side

brush button in this mode, the panel would display

one of the following codes:

DSEGMENT 0 -- Rightmost segment of the gas

gauge. This segment would indicate that the

side brush actuator output was shorted to

ground when the controller was expecting it

to be open.

DSEGMENT 0, 1 -- First and second segments

from the right of the gas gauge. These

segments would indicate that the side brush

actuator output was open when the

controller was trying to short it to ground.

DSEGMENT 2 -- Third segment from the right of

the gas gauge. This segment would indicate

that the side brush motor output was shorted

to ground when the controller was expecting

it to be open.

DSEGMENT 2, 3 -- Third and forth segments

from the right of the gas gauge. These

segments would indicate that the side brush

motor output was open when the controller

was trying to short it to ground.

SQUEEGEE LED

Problem with the squeegee actuator or vacuum

fan motor outputs. If the operator pushes the

squeegee button in this mode, the panel would

display one of the following codes:

DSEGMENT 0 -- Rightmost segment of the gas

gauge. This segment would indicate that the

squeegee actuator output was shorted to

ground when the controller was expecting it

to be open.

DSEGMENT 0, 1 -- First and second segments

from the right of the gas gauge. These

segments would indicate that the squeegee

actuator output was open when the

controller was trying to short it to ground.

DSEGMENT 2 -- Third segment from the right of

the gas gauge. This segment would indicate

that the vacuum fan motor output was

shorted to ground when the controller was

expecting it to be open.

DSEGMENT 2, 3 -- Third and forth segments

from the right of the gas gauge. These

segments would indicate that the vacuum

fan motor output was open when the

controller was trying to short it to ground.

ELECTRICAL

4-32 7400 MM428 (12--98)

SCRUB LED

Problem with the main brush actuator or motor

outputs. If the operator pushes the scrub button in

this mode, the panel would display one of the

following codes:

DSEGMENT 0 -- Rightmost segment of the gas

gauge. This segment would indicate that the

main brush actuator output was shorted to

ground when the controller was expecting it

to be open.

DSEGMENT 0, 1 -- First and second segments

from the right of the gas gauge. These

segments would indicate that the main brush

actuator output was open when the

controller was trying to short it to ground.

DSEGMENT 2 -- Third segment from the right of

the gas gauge. This segment would indicate

that the main brush motor output was

shorted to ground when the controller was

expecting it to be open.

DSEGMENT 2, 3 -- Third and forth segments

from the right of the gas gauge. These

segments would indicate that the main brush

motor output was open when the controller

was trying to short it to ground.

DETERGENT LED

Problem with the headlight or detergent pump

outputs. If the operator pushes the detergent

button in this mode, the panel would display one

of the following codes:

DSEGMENT 0 -- Rightmost segment of the gas

gauge. This segment would indicate that the

detergent pump output was shorted to

ground when the controller was expecting it

to be open.

DSEGMENT 0, 1 -- First and second segments

from the right of the gas gauge. These

segments would indicate that the detergent

pump output was open when the controller

was trying to short it to ground.

DSEGMENT 2 -- Third segment from the right of

the gas gauge. This segment would indicate

that the headlight output was shorted to

ground when the controller was expecting it

to be open.

DSEGMENT 2, 3 -- Third and forth segments

from the right of the gas gauge. These

segments would indicate that the headlight

pump output was open when the controller

was trying to short it to ground.

ELECTRICAL

4-33

7400 MM428 (12--98)

Operating Mode Entry Sequence

(how to activate)

Pressure Adjust Mode; Adjust the pressure

levels for the three down pressure settings.

1. Push and hold the Side Brush button

2. Turn on the key

3. Hold the Side Brush button until the

maintenance light comes on.

4. Release the Side Brush button

PRESSURE ADJUST MODE

When the machine is in this mode, the operator

can adjust the down pressures for the main and

side brushes. When the operator adjusts down

pressure number 3, pressures 1 and 2 are

automatically calculated and stored. The operator

may make independent adjustments to pressures

1 and 2 after storing number 3. These

adjustments will influence only the currently

displayed setting.

The operator can change the pressure settings by

pressing and holding the scrub button. When the

side brush is inactive and the main brush is

active, the operator can adjust the down pressure

for the main brush. When the side brush and main

brush are active, the operator can adjust the

down pressure for the side brush.

To store the new down pressure settings, turn off

the Side Brush and Scrub Panel LEDs on the

touch panel. Then turn off the key switch.

The operation of the Pressure Adjust Mode is as

follows:

SCRUB BUTTON

Pressing the Scrub button will start the normal

scrub sequence. When scrub is active the

following controls and displays take on alternate

functions.

DGAS GAUGE -- The gas gauge in the pressure

adjust mode displays the relative down

pressure of the main (when the side brush is

inactive) or the side brush (when the side

brush is active).

DSQUEEGEE BUTTON -- Holding the squeegee

button will decrease the down pressure.

DDETERGENT BUTTON -- Holding the

detergent button will increase the down

pressure.

NOTE: To return to the factory brush pressure

settings, run RESET SCRUB PRESSURES from

the Diagnostics menu.

ELECTRICAL

4-34 7400 MM428 (12--98)

Operating Mode Entry Sequence

(how to activate)

Reset Scrub Pressures; Return the down

pressure settings to the factory defaults.

1. Push and hold the Scrub button

2. Turn on the key

3. Hold the Scrub button

4. Wait for the maintenance light

5. While holding the Scrub button, press and hold

the Side Brush button

6. Wait for the maintenance light to go out

7. Release the Scrub and Side Brush buttons

8. Turn the key off

9. Restart the machine

RESET SCRUB PRESSURES

When the machine goes into this mode, the

controller replaces the current brush down

pressure settings with factory defaults. To initiate,

follow the entry sequence (how to activate). The

pressures will automatically reset.

ELECTRICAL

4-35

7400 MM428 (12--98)

TROUBLESHOOTING

The following troubleshooting section is organized

with the section of the electrical schematic that

pertains to that particular problem first, followed

by the flow chart.

ELECTRICAL

4-36 7400 MM428 (12--98)

1/RED

19B/BLU

13D/BLK

23/GRY

CB--1

15A

18A/

ORA

18/ORA

8730

5.0A

22/

YEL

8685 M3

1E/

RED

CB--6

19/BLU

IGNITION

SWITCH

S--3

20A/BLU

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

13/BLK

BATTERY

22 13S/BLK

INSTRUMENT PANEL

DOES NOT POWER UP

(SCHEMATIC)

OPERATION:

--KEY SWITCH ACTIVATES

M3 AND M4

--M3 CONTACT SUPPLIES

14VDC TO INSTRUMENT

PANEL (PIN 1)

BATTERY

LINE

SWITCHED

LINE

ELECTRICAL

4-37

7400 MM428 (12--98)

INSTRUMENT PANEL

DOES NOT POWER UP

(FLOW CHART)

TURN KEY ON

ENGINE NEED NOT BE RUNNING

REMOVE M3 RELAY

WORKS

PROBLEM

SOLVED

INSTALL NEW M3

RELAY

CHECK FOR BAT.

VOLTAGE AT M3

(PIN 85) 18A/ORA

BATTERY

VOLTAGE

CHECK FOR BAT.

VOLTAGE AT KEY

SWITCH 20/BLU

VOLTAGE VOLTAGE

20/BLUE,

18/ORA, OR

CB--1 ARE OPEN

CHECK FOR BAT.

VOLTAGE AT KEY

SWITCH 1D/RED

VOLTAGE

DOES NOT

WORK

REPLACE KEY

SWITCH

1D/RED IS OPEN

FROM BATTERY

TO KEY SWITCH

CHECK FOR BAT.

VOLTAGE AT M3

(PIN 30) 22/YEL

NO VOLTAGE

WIRE 22/YEL,

CB--6, OR

1E/RED ARE OPEN

BATTERY

VOLTAGE

OPEN

REPLACE DIODE OR

REPAIR OPEN WIRES

DISCONNECT INSTRUMENT

PANEL

CHECK CONTINUITY OF:

23/GREY FROM M3 (PIN 87)

TO (PIN 1) OF PANEL

13S/BLACK FROM (PIN 22)

OF PANEL TO BAT. NEG.

REPLACE

INSTRUMENT

PANEL

GOOD

CONTINUITY

OPEN WIRE

REPAIR OR REPLACE

OPEN WIRES

OPERATION:

--KEY SWITCH ACTIVATES

M3 AND M4

--M3 CONTACT SUPPLIES

14VDC TO INSTRUMENT

PANEL (PIN 1)

CHECK CONTINUITY OF

WIRES 19/BLU AND 13D/

BLK AND CHECK DIODE

AT M3 (PIN 86) 19/BLU

ELECTRICAL

4-38 7400 MM428 (12--98)

24/

PUR

21/GRY

21B/

GRY 47/BRN

48/GRY

46A/BRN

46/

BRN

24B/PUR

SV--7 SCRUB BR.

UP HOLD VALVE

SV--3 SQUEEGEE

DOWN VALVE

CB--7

24B/PUR

21B/GRY

SV--2 VAC FAN

ON VALVE

SV--6 SIDE BR.

ON VALVE

SV--4 SCRUB BR. DN. FORCE

PROP. VALVE

SV--5 SCRUB BR.

DOWN VALVE

45/GRY

46A/BRN

21 (8 SEC

DELAY)

11 (4 SEC

15 AMP

SV--1 SCRUB BR.

ON VALVE

1F/RED

OPERATION:

--SCRUB IS SELECTED ON

TOUCH PANEL

--SCRUB SOLENOIDS ARE

TURNED ON

--HEAD WILL LOWER,

BRUSHES WILL SPIN

SCRUB BRUSH WILL NOT

TURN ON AND/OR DOWN

(SCHEMATIC)

813R/BLK

36/GRN

FLOW SWITCH

S--15

REVERSE

1/RED

19B/BLU

13D/BLK

23/GRY

CB--1

15A

18A/

ORA

18/ORA

8730

5.0A M3

22/

YEL

8685 M3

1E/

RED

CB--6

19/BLU

IGNITION

SWITCH

S--3

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

13/BLK

BATTERY

22 13S/BLK

13T/BLK

13U/BLK

13Y/BLK

DELAY)

8685M4

19A/BLU

ELECTRICAL

4-39

7400 MM428 (12--98)

46/BRN IS OPEN

FROM PANEL PIN TO

SOLENOID WITHOUT

VOLTAGE

OPERATION:

--SCRUB IS SELECTED ON

TOUCH PANEL

--SCRUB SOLENOIDS ARE

TURNED ON

--HEAD WILL LOWER,

BRUSHES WILL SPIN

SCRUB BRUSH WILL NOT

TURN ON AND/OR DOWN

(FLOW CHART)

PANEL IS POWERED UP

KEY IS ON

ENGINE IS OFF

CAN THE SCRUB BUTTON

BE TURNED ON AND OFF ?

REPLACE TOUCH

PANEL FACE

STILL NOT TURNING

ON/OFF

REPLACE INSTRUMENT

PANEL

YES

ENGINE IS ON

ACTIVATE SQ. / VAC BUTTON

DOES THE SQUEEGEE GO DOWN

AND VAC FAN TURN ON ?

YES

IS THE REC TANK

LIGHT ON ? YES

DRAIN THE TANK

ENGINE IS OFF

KEY IS ON

SCRUB SELECTED

ALL 24/PUR WIRES, 21B/GRY

21/GRY, 1F/RED, OR M4

CONTACTS ARE OPEN

DISCONNECT SOLENOIDS

CHECK VOLTAGE AT SV--1,

SV--5, SV--7, AND SV--4

FROM 24/PUR TO GROUND

VOLTAGE

WIRE 24/PUR

FROM CB--7 TO

SOLENOIDS SV--1,

SV--5, SV--7, OR

SV--4 IS OPEN

VOLTAGE

ENGINE IS OFF

KEY IS ON

SCRUB SELECTED

DISCONNECT SOLENOIDS

CHECK VOLTAGE AT SV--1,

SV--5, AND SV--7

FROM 24/PUR TO 46/BRN

VOLTAGE ON AT LEAST

ONE SOLENOID

NO VOLTAGE

AT ALL SOLENOIDS

SOLENOID STILL DISCONNECTED

TURN KEY SW. OFF THEN ON

DOES THE ” OK” LIGHT COME ON ? YES

WIRE 46/BRN IS OPEN

FROM PANEL (PIN 19)

DISCONNECT INST. PANEL

CHECK CONTINUITY OF

WIRE 46/BRN FROM INST.

PANEL HARNESS (PIN 19)

TO GROUND

OPEN

REPLACE INST.

PANEL

CONTINUED ON

NEXT PAGE CONTINUITY

WIRE 46/BRN IS

SHORTED TO

GROUND

ELECTRICAL

4-40 7400 MM428 (12--98)

CONTINUED FROM

KEY ON

ENGINE OFF

SCRUB SELECTED

SV--4 DISCONNECTED

CHECK VOLTAGE AT SV--4

FROM 24/PUR TO 48/BRN

NO VOLTAGE

SOLENOID STILL

DISCONNECTED

TURN KEY OFF, THEN ON

DOES THE ”OK” LIGHT COME ON ?

NO YES

WIRE48/GRYISOPEN

FROM SV--4 TO INST.

PANEL (PIN 16)

KEY IS OFF

DISCONNECT INSTRUMENT PANEL

CHECK CONTINUITY FROM 48/GRY

TO GROUND

OPEN CONTINUITY

REPLACE PANEL WIRE 48/GRY IS

SHORTED TO GROUND

VOLTAGE

CHECK TO SEE IF ALL

FOUR SOLENOIDS ARE

O N -- -- U S E M A G N E T I S M

TEST ON SV--1, SV--5,

SV--7, AND SV--4

ALL ON ONE OR

MORE NOT

ACTIVATED

REPLACE BAD SOLENOID

HYDRAULIC

PROBLEM

>2VOLTS

ELECTRICAL

4-41

7400 MM428 (12--98)

SQUEEGEE AND VACUUM FAN NOT

TURNING ON AND GOING DOWN

(SCHEMATIC)

OPERATION:

--SQ/VAC IS SELECTED ON

TOUCH PANEL

--WITH MACHINE IN FWD

OF NEUT., SV--3 AND SV--2

ARE TURNED ON

--SQ. LOWERS AND VAC

TURNS ON

24/

PUR

21/GRY

21B/

GRY 47/BRN

48/GRY

46A/BRN

46/

BRN

24B/PUR

SV--7 SCRUB BR.

UP HOLD VALVE

SV--3 SQUEEGEE

DOWN VALVE

CB--7

24B/PUR

21B/GRY

SV--2 VAC FAN

ON VALVE

SV--4 SCRUB BR. DN. FORCE

PROP. VALVE

SV--5 SCRUB BR.

DOWN VALVE

45/GRY

46A/BRN

21 (8 SEC

DELAY)

15 AMP

SV--1 SCRUB BR.

ON VALVE

1F/RED

813R/BLK

36/GRN

FLOW SWITCH

S--15

REVERSE

1/RED

19B/BLU

13D/BLK

23/GRY

CB--1

15A

18A/

ORA

18/ORA

8730

5.0A M3

22/

YEL

8685 M3

1E/

RED

CB--6

19/BLU

IGNITION

SWITCH

S--3

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

13/BLK

BATTERY

22 13S/BLK

13T/BLK

13U/BLK

13Y/BLK

11 (4 SEC

DELAY)

8685M4

19A/BLU

ELECTRICAL

4-42 7400 MM428 (12--98)

CHECK REVERSE INPUT

--DISCONNECT INSTRUMENT

PANEL

--TURN ENGINE ON, MACHINE

IN REVERSE

--CHECK CONTINUITY AT THE

INSTR. PANEL (PIN 8) FROM

36/GRN TO GROUND

ELECTRONICS OK

SEE HYDRAULIC

TROUBLESHOOTING

DOES THE SQ. AND/OR

VAC TURN ON/OFF WITH THE

SQ/VAC BUTTON NOW ?

CAN THE SQ/VAC TOUCH

PANEL BUTTON

BE TURNED ON AND OFF?

SQUEEGEE AND VACUUM FAN NOT

TURNING ON AND GOING DOWN

(FLOW CHART)

OPERATION:

--SQ/VAC IS SELECTED ON

TOUCH PANEL

--WITH MACHINE IN FWD

OF NEUT., SV--3 AND SV--2

ARE TURNED ON

--SQ. LOWERS AND VAC

TURNS ON

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

YES

REPLACE TOUCH

PANEL FACE

STILL DOES

NOT WORK

REPLACE INST.

PANEL

GO INTO ”MANUAL MODE”

THE OUTPUTS WILL TURN

ON REGARDLESS OF THE

INPUTS

--TURN KEY OFF

--PUSH AND HOLD ”ES”

BUTTON

--TURN KEY ON

--KEEP HOLDING ”ES” BUT-

TON UNTIL THE MAINTE-

NANCE LIGHT COMES ON

--RELEASE ”ES” BUTTON

CHECK VOLTAGE AT SV--3

FROM 24P/PUR TO GRND. AND

SV--2 FROM 24/PUR TO GRND.

VOLTAGE

--MANUAL MODE

--ENGINE OFF

--KEY ON

--SQ/VAC SELECTED

”ON”

ARE SV--2 AND SV--3

TURNED ON ? (USE

MAGNETIZED TEST)

YES

DISCONNECT HYD.

COILS

CHECK VOLTAGE

ACROSS BOTH COILS,

SV--2 FROM 24/PUR TO

45/GRY AND SV--3 FROM

24/PUR TO 47/BRN

VOLTAGE

CONTINUED ON

REPLACE HYD. COIL

THAT WILL NOT TURN

ON----RE--TEST SYSTEM

24/PUR, 21/GRY,

CB--7, OR M--4

CONTACTS ARE

OPEN

YES

IS THE REC TANK

FULL LIGHT ON ?

YES

DRAIN TANK AND

RE--TEST

OPEN

CONTINUITY

REPLACE THE

PANEL

36/GRN, 13R/BLK, OR

S--15 ARE OPEN

NOTE: S--15 IS

CLOSED IN REVERSE

ELECTRICAL

4-43

7400 MM428 (12--98)

REMOVE THE SHORT

TO GROUND ON

47/BRN AND/OR

45/GRY

COILS STILL

DISCONNECTED

CONTINUED FROM

--TURN KEY OFF THEN ON

IS THE ”OK” LIGHT ON ?

YES

WIRE 47/BRN OR

WIRE 45/GRY

ARE OPEN

KEY OFF

PANEL

DISCONNECTED

CHECK CONTINUITY OF

47/BRN AND 45/GRY TO

GROUND

OPEN

CONTINUITY

--RECONNECT PANEL

--KEY OFF THEN ON

DOES THE ”OK” PANEL

LIGHT COME ON ?

YESNO

RE--TEST

SYSTEM

REPLACE

INSTRUMENT PANEL

ELECTRICAL

4-44 7400 MM428 (12--98)

CIRCUIT 1

CIRCUIT 2

S10

46C/BRN

46B/BRN

25/

GRY

21/GRY

51A/PUR

51/PUR51C/PUR

S10

97/YEL

25B/GRY

SV--11 SIDE BR.

UP HOLD VALVE

SV--12 LOW

WATER VALVE

SV--13 HIGH

WATER VALVE

95/BLU

96/GRY

21A/

GRY

15 AMP

CB--8

51B/PUR

SV--14 SIDE BR.

WATER VALVE

SV--10 SIDE BR. DN. FORCE

PROP. VALVE

25C/GRY

SV--9 SIDE BR.

OUT VALVE

SV--8 SIDE BR.

DOWN VALVE

SV--6 SIDE BR.

ON VALVE

52/YEL

51A/PUR

6 (3 SEC. DELAY)

1F/RED

SIDE BRUSH WILL NOT TURN ON

AND GO DOWN

(SCHEMATIC)

OPERATION:

--MACHINE MUST BE IN

SCRUB MODE

--SIDE BRUSH BUTTON IS

ACTIVATED AND WILL

TURN ON AND LOWER

SIDE BRUSH

-- S V -- 6 , S V -- 9 , S V -- 8 , S V -- 1 0 ,

AND SV--11 WILL BE ON

813R/BLK

36/GRN

FLOW SWITCH

S--15

REVERSE

1/RED

19B/BLU

13D/BLK

23/GRY

CB--1

15A

18A/

ORA

18/ORA

8730

5.0A M3

22/

YEL

8685 M3

1E/

RED

CB--6

19/BLU

IGNITION

SWITCH

S--3

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

13/BLK

BATTERY

22 13S/BLK

13T/BLK

13U/BLK

13Y/BLK

8685M4

19A/BLU

ELECTRICAL

4-45

7400 MM428 (12--98)

51/PUR IS OPEN

FROM PANEL (PIN

12) TO SOLENOID

WITHOUT VOLTAGE

25/GRY, 21A/GRY, OR

CB--8 IS OPEN FROM

SOLENOID TO M--4

(PIN 87)

GO TO SCRUB

TROUBLESHOOTING

FLOW CHART FIRST

REPLACE TOUCH

PANEL FACE

CAN THE SCRUB AND SIDE

BRUSH BUTTONS BE TURNED

ON AND OFF

SIDE BRUSH WILL NOT TURN ON

AND GO DOWN

(FLOW CHART)

OPERATION:

--MACHINE MUST BE IN

SCRUB MODE

--SIDE BRUSH BUTTON IS

ACTIVATED AND WILL

TURN ON AND LOWER

SIDE BRUSH

-- S V -- 6 , S V -- 9 , S V -- 8 , S V -- 1 0 ,

AND SV--11 WILL BE ON

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

YES

STILL DOES

NOT WORK

REPLACE INST.

PANEL

--ENGINE ON

ACTIVATE THE SCRUB BUTTON

DO THE SCRUB FUNCTIONS TURN ON ?

YESNO

--ENGINE OFF

--KEY ON

--SCRUB SELECTED

--SIDE BRUSH SELECTED

CHECK VOLTAGE AT SV--6, SV--8, SV--9,

SV--10, AND SV--11 FROM 25/GRY TO

GROUND

VOLTAGE

NO VOLTAGE

ON ANY OR

ALL

--ENGINE OFF

--KEY ON

--SCRUB SELECTED

--SIDE BRUSH SELECTED

--ALL FOUR SOLENOIDS DISCONNECTED

CHECK VOLTAGE ACROSS SOLENOIDS

SV--6, 8, 9, AND 11 FROM 25/GRY TO 51 PUR

CONTINUED ON

VOLTAGE ACROSS

ALL FOUR SOLENOIDS

VOLTAGE ACROSS

AT LEAST ONE SOLENOID

NO VOLTAGE

ON ALL FOUR

--SOLENOIDS STILL DISCONNECTED

--TURN KEY OFF, THEN ON

DOES THE ”OK” LIGHT COME ON ? YES

51/PUR IS OPEN

FROM PANEL TO ALL

FOUR SOLENOID

--DISCONNECT INSTRUMENT PANEL

CHECK CONTINUITY OF 51/PUR FROM

INSTR. PANEL (PIN 12) TO GROUND

OPEN

CONTINUITY

REPLACE INST.

PANEL

WIRE 51/PUR IS

SHORTED TO

GROUND

ELECTRICAL

4-46 7400 MM428 (12--98)

--KEY OFF

PANEL DISCONNECTED

CHECK CONTINUITY FROM

52/YEL TO GROUND

WIRE 52/YEL IS OPEN

FROM SV--10 TO

INSTR. PANEL (PIN 6)

--KEY ON

--ENGINE OFF

--SCRUB AND SIDE BRUSH ON

--SV--10 DISCONNECTED

CHECK VOLTAGE AT SV--10 FROM

25/GRY TO 52/YEL

CONTINUED FROM

NO VOLTAGE

VOLTAGE

WITH SOLENOID STILL DISCONNECTED----

TURN KEY OFF, THEN ON

DOES THE :OK” LIGHT COME ON ?

NO YES

WIRE 52/YEL

IS SHORTED

TO GROUND

CONTINUITYOPEN

REPLACE INSTRUMENT

PANEL

CHECK TO SEE IF ALL SOLENOIDS

ARE TURNING ON

USE THE MAGNETIC TEST

ONE OR

MORE OFF

REPLACE BAD

SOLENOIDS

ALL SOLENOIDS

HYDRAULIC PROBLEM

SEE TROUBLESHOOTING

>2VOLTS

ELECTRICAL

4-47

7400 MM428 (12--98)

WATER VALVES NOT OPERATING

(SCHEMATIC) OPERATION:

--SCRUB FUNCTIONS MUST

BE ON

--WATERSWITCHINPOSITION#1

TURNS ON SV--12 LOW WATER

VALVE AND SV--14 SIDE BRUSH

VALVE

--WATERSWITCHINPOSITION#2

TURNS ON SV--12, SV--14, AND

SV--13 (HIGH WATER VALVE)

CIRCUIT 1

CIRCUIT 2

S10

46C/BRN

46B/BRN

25/

GRY

21/GRY

51A/PUR

51/PUR51C/PUR

S10

97/YEL

25B/GRY

SV--11 SIDE BR.

UP HOLD VALVE

SV--12 LOW

WATER VALVE

SV--13 HIGH

WATER VALVE

95/BLU

96/GRY

21A/

GRY

15 AMP

CB--8

51B/PUR

SV--14 SIDE BR.

WATER VALVE

SV--10 SIDE BR. DN. FORCE

PROP. VALVE

25C/GRY

SV--9 SIDE BR.

OUT VALVE

SV--8 SIDE BR.

DOWN VALVE

SV--6 SIDE BR.

ON VALVE

52/YEL

51A/PUR

6 (3 SEC. DELAY)

1F/RED

813R/BLK

36/GRN

FLOW SWITCH

S--15

REVERSE

1/RED

19B/BLU

13D/BLK

23/GRY

CB--1

15A

18A/

ORA

18/ORA

8730

5.0A M3

22/

YEL

8685 M3

1E/

RED

CB--6

19/BLU

IGNITION

SWITCH

S--3

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

13/BLK

BATTERY

22 13S/BLK

13T/BLK

13U/BLK

13Y/BLK

8685M4

19A/BLU

ELECTRICAL

4-48 7400 MM428 (12--98)

TROUBLESHOOT THE

SCRUB FUNCTION

AND SIDE BRUSH

FUNCTION FIRST

ACTIVATE SCRUB AND SIDE BRUSH

DO THEY BOTH TURN ON AND COME DOWN ?

WATER VALVES NOT OPERATING

(FLOW CHART) OPERATION:

--SCRUB FUNCTIONS MUST

BE ON

--WATERSWITCHINPOSITION#1

TURNS ON SV--12 LOW WATER

VALVE AND SV--14 SIDE BRUSH

VALVE

--WATERSWITCHINPOSITION#2

TURNS ON SV--12, SV--14, AND

SV--13 (HIGH WATER VALVE)

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

YES NO

--ENGINE RUNNING

--SCRUB AND SIDE BRUSH ON

--WATERSWITCHONPOSITION#2

--SV--14, SV--12, AND SV--13 DISCONNECTED

CHECK FOR VOLTAGE AT SV--14 FROM

97/YEL TO GROUND

CHECK FOR VOLTAGE AT SV--12 FROM

96/GRY TO GROUND

CHECK FOR VOLTAGE AT SV--13 FROM

95/BLU TO GROUND

NO VOLTAGE ON ANY

WIRES 97/YEL, 96/GRY, 95/BLU

25/GRY, OR SWITCH S--10 ARE

OPEN FROM CB--8 TO SOLENOID

WITH NO VOLTAGE

VOLTAGE ON

ALL SOLENOIDS

--KEY ON, ENGINE OFF

--SOLENOIDS STILL DISCONNECTED

--SCRUB AND SIDE BRUSH ON

CHECK VOLTAGE AT SV--14 FROM

97/YEL TO 51B/PUR

CHECK VOLTAGE AT SV--12 FROM

96/GRY TO 46B/BRN

CHECK VOLTAGE AT SV--13 FROM

95/BLU TO 46C/BRN

NO VOLTAGE ON ANY

VOLTAGE ON

ALL SOLENOIDS

REPLACE ANY VALVE

NOT OPERATING

--IF SV--14 IS NO VOLTAGE

WIRE 51B/PUR FROM SV--14 TO

(PIN 12) IS OPEN

--IF SV--12 IS NO VOLTAGE

WIRE 46B/BRN FROM SV--12 TO

(PIN 19) IS OPEN

--IF SV--13 IS NO VOLTAGE

WIRE 46C/BRN FROM SV--13 TO

(PIN 19) IS OPEN

ELECTRICAL

4-49

7400 MM428 (12--98)

13S/BLK

13T/BLK

13Y/BLK

62E/BRN

62D/BRN

62B/YEL

62A/YEL

59A/BRN

59/

BRN

20B/

BLU

62C/YEL

ELECTRONIC

INSTRUMENT

PANEL

8730

BRAKE SWITCH

S--11

REV/FLSH LIGHT LRC

89/ORG

CB--3

13HH/

BLK

13II/

BLK

13DD/BLK

13CC/BLK

13KK/BLK

62/YEL

89A/ORA

89B/ORA

15 AMP

TAIL LHT L.H.

TAIL LHT R.H.

HEADLIGHT L.H.

HEADLIGHT R.H.

23C/GRY 60/GRN

LIGHTS

85 86

CB--1

15A

IGNITION

SWITCH

S--3 20A/BLU

20/BLU

BATT.

ACC

START

15B/BLU

15/BLU

14/GRN

18A/ORA 13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

HEAD LIGHTS WILL NOT TURN ON

(SCHEMATIC) OPERATION:

--(PIN 15) TO GROUND BY OIL

PRESSURE SWITCH TURNS ON M6

1/RED 13/BLK

BATTERY

13U/BLK

18A/ORA

23/GRY

18A/

ORA

8730

5.0A

22/

YEL

8685 M3

1E/

RED

CB--6

19/BLU 13D/BLK

1E/

RED

1D/RED

ELECTRICAL

4-50 7400 MM428 (12--98)

-- P O W E R O F F

--DISCONNECT PANEL

IS 60/GRN SHORTED

TO GROUND ?

WIRES 15/BLU, 13B/BLK, OR S--4 ARE

OPEN, OR ENGINE OIL PRESSURE

IS LOW

DISCONNECT M6 AND CHECK

CONTINUITY OF 60/GRN

FROM M6 (PIN 86) TO INSTR.

PANEL (PIN 20)

CHECK VOLTAGE ON M6 AT

(PIN 30) FROM 59/BRN TO

GROUND

REMOVE M6 RELAY

CHECK VOLTAGE AT M6

(PIN 85) FROM 23C/GRY

TO GROUND

HEAD LIGHTS WILL NOT TURN ON

(FLOW CHART) OPERATION:

--(PIN 15) TO GROUND BY OIL

PRESSURE SWITCH TURNS ON M6

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

VOLTAGE

NO VOLTAGE

CHECK VOLTAGE AT M6 (PIN 87)

FROM 59/BRN TO GROUND VOLTAGE

NO VOLTAGE

WIRE 20B/BLU IS OPEN FROM

KEY SWITCH TO CB--3

CHECK VOLTAGE AT HEAD LIGHTS

FROM 62/YEL TO 13CC/BLK OR

FROM 62A/YEL TO 13DD/BLK

HEAD LIGHT IS BAD

62/YEL, 62A/YEL,

13CC/BLK, OR 13DD/

BLK ARE OPEN

VOLTAGENO VOLTAGE

REPLACE M6 RELAY

WORKS

PROBLEM SOLVED

NO LIGHTS

VOLTAGE

WIRE 23C/GRY IS OPEN

FROM M6 (PIN 85) TO

M3 (PIN 87)

IS THE ENGINE OIL PRESSURE

WARNING LIGHT ”ON” ON THE

INSTRUMENT PANEL ?

NO VOLTAGE

YES

CONTINUITY

OPEN

REPAIR 60/GRN DOES ”OK” LIGHT COME

ON WHEN KEY IS

TURNED ON ?

YES

GROUND AT (PIN 15)

REPLACE INSTR.

PANEL

--DISCONNECT THE INSTR. PANEL

--START ENGINE

CHECK FOR GROUND ON 15/BLU

AT INSTR. PANEL ON (PIN 15)

15/BLU, S--4, OR 13B/BLK

IS OPEN

REPLACE INSTR.

PANEL

YES

REPAIR 60/GRN

ELECTRICAL

4-51

7400 MM428 (12--98)

5 SEC. DELAY

ES PUMP RUNS

30 SEC.

5 SEC. DELAY

1MIN.TOVAC

FAN SHUT--OFF

13K/BLK

23C/GRY

27/PUR

26/BRN

RECOVERY

TANK

SOLUTION

TANK

S--18 N.C.H.O.

S--17 N.O.H.C.

N.C.H.O.

28/YEL

57/GRN

ES PUMP

85 86

RECOVERY TANK

S--8

IGNITION

SWITCH

S--3

13J/BLK

1D/RED

20A/BLU

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

66/BRN 13PP/BLK

AUTO FILL

65/GRY

CB--2

ES PUMP

20A/

BLU 8730

15 AMP

MTR

EStPUMP NOT WORKING

(SCHEMATIC) OPERATION:

-- I F E S tIS SELECTED ON PANEL AND

--S--17 AND S--18 CLOSE FOR 5 SECONDS

--M5 RELAY WILL ACTIVATE, TURNING ON

PUMP

13T/BLK

13Y/BLK

CB--1

15A

15B/BLU

15/BLU

14/GRN

18A/ORA 13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

1/RED 13/BLK

BATTERY

13U/BLK

18A/ORA

23/GRY

18A/

ORA

30 M3

22/

YEL

8685 M3

1E/

RED

19/BLU 13D/BLK

13S/BLK

23/GRY

15/BLU

ELECTRICAL

4-52 7400 MM428 (12--98)

DISCONNECT INSTR. PANEL

--CHECK FOR CONTINUITY

AT INSTR. PANEL FROM

26/BRN (PIN 3) TO GROUND STILL NOT

WORKING IN

MANUAL MODE

CAN THE ES PUMP TOUCH

PANEL BUTTON BE

TURNED ON/OFF

EStPUMP NOT WORKING

(FLOW CHART) OPERATION:

-- I F E S tIS SELECTED ON PANEL AND

--S--17 AND S--18 CLOSE FOR 5 SECONDS

--M5 RELAY WILL ACTIVATE, TURNING ON

PUMP

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

YES REPLACE TOUCH

PANEL FACE

STILL DOES

NOT WORK

REPLACE INST.

PANEL

GO INTO ”MANUAL MODE”

THE OUTPUTS WILL TURN ON

REGARDLESS OF THE INPUTS

--TURN KEY OFF

--PUSH AND HOLD ”ES” BUTTON

--TURN KEY ON

--KEEP HOLDING ”ES” BUTTON

UNTIL THE MAINTENANCE LIGHT

COMES ON

--RELEASE ”ES” BUTTON

YES DOES THE ES PUMP TURN

ON AND OFF WITH THE ES

BUTTON NOW ?

INPUT OUTPUT

REPLACE M5

CHECK VOLTAGE AT

M5 (PIN 30) FROM 65/GRY

TO GROUND

NO VOLTAGE

CHECK VOLTAGE AT M5

(PIN 85) FROM 23C/GRY

TO GROUND

VOLTAGE

20A/BLU, CB--2, OR 65/GRY

ARE OPEN FROM M5 (PIN 30)

TO KEY SWITCH

CONTINUED ON

23C/GRY IS OPEN FROM

M5 (PIN 85) TO M3 (PIN 87)

CHECK FLOAT

INPUT

KEY

OFF

YES

26/BRN, S--17, 27/PUR,

S--18, OR 13K/BLK

OPEN

KEY ON

PANEL CONNECTED

GO TO INPUT MODE

APPLY AND RE-

MOVE GROUND TO

(PIN 3) BY CLOSING

S--17 AND S--18

YES

REPLACE PANEL

SYSTEM O.K.

VOLTAGE

NO VOLTAGE

ELECTRICAL

4-53

7400 MM428 (12--98)

WIRE 66/BRN OR

13PP/BLK ARE

OPEN

57/GRN IS OPEN FROM

(PIN 4) ON INSTR. PAN-

EL TO (PIN 86)

CONTINUED FROM

VOLTAGE

NO VOLTAGE

WITH ES ON AND

MACHINE IN

MANUAL MODE

CHECK VOLTAGE AT M5 (PIN 87)

FROM WIRE 66/BRN TO GROUND

WITH ES ON AND

MACHINE IN

MANUAL MODE

CHECK VOLTAGE AT ES PUMP

FROM 66/BRN TO 13PP/BLK

NO VOLTAGE VOLTAGE

MOTOR BAD

WITH M5 REMOVED

TURN KEY ON, THEN OFF

IS ”OK” LIGHT ON ?

NO YES

PANEL DISCONNECTED

POWER OFF

M5 REMOVED

REPLACE PANEL

YES

REMOVE SHORT TO

GROUND ON 57/GRN

CHECK CONTINUITY

FROM 57/GRN TO

GROUND

ELECTRICAL

4-54 7400 MM428 (12--98)

23C/GRY

13R/BLK

58/BLU

REVERSE

85 86

36/GRN

18A/

ORA

FLOW SWITCH

5.0A

S--15 REVERSE

22/

YEL

CB--6

13RR/BLK

13JJ/BLK

93A/ORA

93/ORA

20C/

BLU 92/PUR M7

8730

CB--4 94/YEL

93B/ORA

15 AMP

BACK--UP ALARM UNIT

FLASHER

REVERSE LIGHT OR ALARM

NOT WORKING

(SCHEMATIC)

OPERATION:

--GROUND AT (PIN 8) WHEN

MACHINE IS IN REVERSE

--TURNS ON M7

--SUPPLIES POWER TO BACK--UP

ALARM/LIGHT

ELECTRONIC

INSTRUMENT

PANEL

ES PUMP

MTR

13T/BLK

13Y/BLK

13U/BLK

13S/BLK

IGNITION

SWITCH

S--3

1D/RED

20A/BLU

20/BLU

BATT.

ACC CB--1

15A

1/RED 13/BLK

BATTERY

23/GRY

19/BLU 13D/BLK

ELECTRICAL

4-55

7400 MM428 (12--98)

M7 STILL REMOVED

TURN KEY OFF THEN

ON, IS ”OK LIGHT ON?

REPAIR OR REPLACE WIRES

93A/ORA, 93B/ORA, OR

94/YEL

CHECK VOLTAGE AT M7

(PIN 85) FROM 23C/GRY

TO GROUND

CHECK CONTINUITY OF WIRES

93/ORA, 93A/ORA, 93B/ORA,

AND 94/YEL

CHECK FOR VOLTAGE FROM

ALARM OR LIGHTS WORK-

ING WIRE OR 13JJ BLK,

13RR/BLK TO BATT POSITIVE

CHECK THE VOLTAGE

FROM THE ALARM OR

LIGHT NOT WORKING TO

GROUND

REVERSE LIGHT OR ALARM

NOT WORKING

(FLOW CHART)

OPERATION:

--GROUND AT (PIN 8) WHEN

MACHINE IS IN REVERSE

--TURNS ON M7

--SUPPLIES POWER TO BACK--UP

ALARM/LIGHT

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

YES

DOES THE BACK--UP ALARM

OR LIGHT WORK

VOLTAGE

NO VOLTAGE

93/ORA, 93B/ORA, 94/YEL

OR FLASHER ARE OPEN

KEY ON

REPLACE M7

STILL NOT

WORKING

REMOVE M7 AND CHECK

VOLTAGE AT M7 (PIN 30)

FROM 92/PUR TO GROUND

NO VOLTAGE

VOLTAGE

92/PUR, 20C/BLU, OR

CB--4 ARE OPEN

NO VOLTAGE

23C/GRY IS OPEN VOLTAGE

VOLTAGE

REPLACE BAD ALARM

OR FLASHER LIGHT

NO VOLTAGE

REPAIR OR REPLACE

13JJ/BLK OR 13RR/BLK

OPEN

CONTINUED ON

YES

POWER OFF

DISCONNECT PANEL

CHECK CONTINUITY ON

WIRE 58/BLU TO GROUND

NOYES

REPLACE

PANEL

58/BLU IS SHORTED

TO GROUND, RE-

PAIR AND REPLACE

ELECTRICAL

4-56 7400 MM428 (12--98)

REPLACE INSTR.

PANEL

36/GRN, 13R/BLK, OR S--15

ARE OPEN AND IN REVERSE

GO INTO ”INPUT” MODE

IS THE 3RD SEGMENT FROM

THE RIGHT TURNING ON WITH

THE MACHINE RUNNING AND IN

REVERSE ?

CONTINUED FROM

DISCONNECT INSTR. PANEL WITH ENGINE

RUNNING AND MACHINE IN REVERSE

CHECK CONTINUITY AT INSTR. PANEL

CONNECTOR (PIN 8) FROM 36/GRN TO

GROUND WHEN MACHINE IS RUNNING

CONTINUITY

NO CONTINUITY

YES

--DISCONNECT PANEL

-- P O W E R O F F

CHECK CONTINUITY

OF 58/BLU

REPLACE INSTR.

PANEL

CONTINUITY OPEN

REPAIR 58/BLU

ELECTRICAL

4-57

7400 MM428 (12--98)

56/ORA 9

23A/GRY MTR

DETERGENT METERING

PUMP IS NOT OPERATING

(SCHEMATIC)

OPERATION:

--PANEL DETERGENT BUTTON IS

ACTIVE IN LOW OR HIGH POSITION

--MACHINE IS IN SCRUB MODE

--DETERGENT PUMP WILL BE TURNED

ON WITH A PULSE WIDTH MODULATED

SIGNAL

18A/

ORA

5.0A

22/

YEL

85 M3

CB--6

ELECTRONIC

INSTRUMENT

PANEL

13T/BLK

13Y/BLK

13U/BLK

13S/BLK

IGNITION

SWITCH

S--3

1D/RED

20/BLU

BATT.

ACC CB--1

15A

1/RED 13/BLK

BATTERY

23/GRY

19/BLU 13D/BLK

ELECTRICAL

4-58 7400 MM428 (12--98)

REPAIR AND

REPLACE

56/ORA

23A/GRY IS OPEN

FROM PUMP TO

M3 (PIN 87)

VERIFY THAT THE SCRUBBING

SYSTEM IS FUNCTIONING

IS 46/BRN AT INSTR. PANEL (PIN 19)

GOING LOW AND TURNING ON

SV--1, SV--5, AND SV--7 ?

--IN MANUAL MODE

--KEY ON, ENGINE OFF

CHECK VOLTAGE AT

PUMP FROM WIRE 23A/

GRY TO 56/ORA

GO INTO ”MANUAL MODE”

THE OUTPUTS WILL TURN ON

REGARDLESS OF THE INPUTS

--TURN KEY OFF

--PUSH AND HOLD ”ES” BUTTON

--TURN KEY ON

--KEEP HOLDING ”ES” BUTTON

UNTIL THE MAINTENANCE LIGHT

COMES ON

--RELEASE ”ES” BUTTON

ENGINE DOES NOT HAVE TO BE

RUNNING

DETERGENT METERING

PUMP IS NOT OPERATING

(FLOW CHART)

OPERATION:

--PANEL DETERGENT BUTTON IS

ACTIVE IN LOW OR HIGH POSITION

--MACHINE IS IN SCRUB MODE

--DETERGENT PUMP WILL BE TURNED

ON WITH A PULSE WIDTH MODULATED

SIGNAL

PANEL IS POWERED UP

KEY IS ON

ENGINE IS RUNNING

REPLACE TOUCH

PANEL FACE

STILL DOES

NOT WORK

REPLACE INST.

PANEL

CAN THE DETERGENT

METERING AND TOUCH

PANEL SWITCHES BE

TURNED ON AND OFF ?

YES

DOES THE DETERGENT METERING

PUMP TURN ON AND OFF WITH

THE TOUCH PANEL SWITCH ?

YES

SCRUB

INPUTS DISCONNECT DETERGENT

PUMP

CHECK VOLTAGE AT DETERGENT

PUMP FROM 23A/GRY TO GROUND

VOLTAGE

NO VOLTAGE

YES

TROUBLESHOOT

SCRUB BRUSH

SYSTEM FIRST

NO VOLTAGE

VOLTAGE

REPLACE

PUMP

-- P O W E R O F F

--PANEL DISCONNECTED

CHECK CONTINUITY OF 56/ORA

FROM PANEL (PIN 9) TO PUMP

OPEN

CONTINUITY

REPLACE INST.

PANEL

DETERGENT METERING

TESTS OUT O.K.

ELECTRICAL

4-59

7400 MM428 (12--98)

1E/RED

1/RED

IGNITION

SWITCH

S--3

55A MAX.

CHARGE

1D/RED

2/ORA

1B/RED

12V

540 C.C.A.

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

SENSE

13A/BLK

STARTER MOTOR

13/BLK

BATTERY

ALTERNATOR

GND

OUT

1A/RED

STARTER RELAY

M1 MTR

ALTERNATOR / BATTERY WARNING LIGHT

STAYS ON WHEN ENGINE IS RUNNING

(SCHEMATIC)

OPERATION:

--CONNECTION L2 ON ALTERNATOR

GOES TO BATTERY POSITIVE WHEN ALTER-

NATOR IS TURNED ON

--BATTERY POSITIVE AT (PIN 14) TURNS OFF

THE ALTERNATOR / BATTERY INDICATOR

18A/

ORA

22/

YEL

20/BLU

CB--1

15A

19/BLU

23/GRY

13D/BLK

5.0A

CB--6

1E/RED

13T/BLK

13Y/BLK

13U/BLK

13S/BLK

ELECTRICAL

4-60 7400 MM428 (12--98)

DISCONNECT INSTR.

PANEL, THEN RECONNECT

IF LIGHT STILL ON----REPLACE

INSTR. PANEL

WIRE 2/ORA IS

SHORTED TO BATTERY

POSITIVE

--ENGINE RUNNING

--PANEL DISCONNECTED

CHECK VOLTAGE OF WIRE

2/ORA AT (PIN 14) OF INSTR.

PANEL

DISCONNECT WIRE 2/ORA

AT THE ALTERNATOR

TOUCH WIRE 2/ORA TO WIRE 1B/RED

AT THE ALTERNATOR

DOES THE ALTERNATOR LIGHT TURN

OFF ?

ALTERNATOR / BATTERY WARNING LIGHT

STAYS ON WHEN ENGINE IS RUNNING

(FLOW CHART)

OPERATION:

--CONNECTION L2 ON ALTERNATOR

GOES TO BATTERY POSITIVE WHEN ALTER-

NATOR IS TURNED ON

--BATTERY POSITIVE AT (PIN 14) TURNS OFF

THE ALTERNATOR / BATTERY INDICATOR

ENGINE RUNNING

CHECK VOLTAGE FROM L2

AT ALTERNATOR TO GROUND VOLTAGE

NO VOLTAGE

KEY ON

ENGINE OFF

YES

TIGHTEN ALTERNATOR BELT

IF NECESSARY

REPLACE ALTERNATOR

DOES LIGHT TURN OFF ?

VOLTAGE

NO VOLTAGE

WIRE2/ORAISOPEN

ELECTRICAL

4-61

7400 MM428 (12--98)

ALTERNATOR / BATTERY WARNING

LIGHT WILL NOT TURN ON

(SCHEMATIC)

OPERATION:

--CONNECTION L2 ON ALTERNATOR

GOES TO BATTERY POSITIVE WHEN ALTER-

NATOR IS TURNED ON

--BATTERY POSITIVE AT (PIN 14) TURNS OFF

THE ALTERNATOR / BATTERY INDICATOR

1E/RED

1/RED

IGNITION

SWITCH

S--3

55A MAX.

CHARGE

1D/RED

2/ORA

1B/RED

12V

540 C.C.A.

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

SENSE

13A/BLK

STARTER MOTOR

13/BLK

BATTERY

ALTERNATOR

GND

OUT

1A/RED

STARTER RELAY

M1 MTR

18A/

ORA

22/

YEL

20/BLU

CB--1

15A

19/BLU

23/GRY

13D/BLK

5.0A

CB--6

1E/RED

13T/BLK

13Y/BLK

13U/BLK

13S/BLK

ELECTRICAL

4-62 7400 MM428 (12--98)

ALTERNATOR IS SHORTED

L2 TO BATTERY POSITIVE

OR WIRE 2/ORA IS SHORTED

TO BATTERY POSITIVE

ALTERNATOR / BATTERY WARNING

LIGHT WILL NOT TURN ON

(FLOW CHART)

OPERATION:

--CONNECTION L2 ON ALTERNATOR

GOES TO BATTERY POSITIVE WHEN ALTER-

NATOR IS TURNED ON

--BATTERY POSITIVE AT (PIN 14) TURNS OFF

THE ALTERNATOR / BATTERY INDICATOR

KEY ON

ENGINE OFF

REMOVE 2/ORA FROM

ALTERNATOR (PIN L2)

GROUND WIRE 2/ORA

DOES THE LIGHT

TURN ON ?

YES

OPEN

REPAIR AND REPLACE

2/ORA

CONTINUITY

REPLACE LAMP L8

INSIDE THE PANEL

CHECK CONTINUITY 2/ORA

FROM ALTERNATOR TO

(PIN 14)

ELECTRICAL

4-63

7400 MM428 (12--98)

543/BLU COOLANT TEMP

SENDER

SE--2

ELECTRONIC

INSTRUMENT

PANEL

ENGINE TEMPERATURE LIGHT

WILL NOT TURN ON OR OFF

(SCHEMATIC)

OPERATION:

--225 DEGREE F. SE--2 =<80 OHMS

--COOLANT LIGHT TURNS ON

13T/BLK

13Y/BLK

13U/BLK

13S/BLK

1/RED

IGNITION

SWITCH

S--3

1D/RED

12V

540 C.C.A.

BATT.

ACC

START

13/BLK

BATTERY

18A/

ORA

30 M3

22/

YEL

20/BLU

CB--1

15A

19/BLU

23/GRY

13D/BLK

5.0A

CB--6

1E/RED

ELECTRICAL

4-64 7400 MM428 (12--98)

ENGINE TEMPERATURE LIGHT

WILL NOT TURN ON

(FLOW CHART)

OPERATION:

--225 DEGREE F. SE--2 =<80 OHMS

--COOLANT LIGHT TURNS ON

DOES THE LIGHT TURN

ON MOMENTARILY AT POWER UP ?

YES

REPLACE LAMP L2

INSIDE PANEL

RETEST

REPLACE INSTR. PANEL

STILL NOT

TURNING ON AT

POWER UP

DISCONNECT SE--2 AND GROUND

WIRE 43/BLU

DOES LIGHT TURN ON ?

YES

WIRE 43/BLU IS

OPEN FROM (PIN 5) TO SE--2

IF ENGINE TEMP IS LESS

THAN 225 DEGREES

REPLACE SE--2

SYSTEM IS OK

ENGINE TEMPERATURE LIGHT

WILL NOT TURN OFF

(FLOW CHART)

OPERATION:

--225 DEGREE F. SE--2 =<80 OHMS

--COOLANT LIGHT TURNS ON

KEY ON

ENGINE OFF

DISCONNECT SE--2

LIGHT STILL ON

LIGHT TURNS OFF

POWER OFF

DISCONNECT PANEL

DISCONNECT SE--2

CHECK CONTINUITY

43/BLU TO GROUND

OPEN

CONTINUITY

REPLACE INSTR. PANEL

WIRE 43/BLU IS

GROUNDED

IF ENGINE TEMP IS LESS

THAN 225 DEGREES

REPLACE SE--2

SYSTEM IS OK

ELECTRICAL

4-65

7400 MM428 (12--98)

13N/BLK

FILTER SWITCH

S--14

HYDRAULIC

35/BRN

OPERATION:

--WHEN S--14 CLOSES, LIGHT

TURNS ON

--THIS LIGHT IS AN OPTION

HYDRAULIC (HIGH) PRESSURE INDICATOR

LIGHT WILL NOT TURN ON OR OFF

(SCHEMATIC)

ELECTRONIC

INSTRUMENT

PANEL

13T/BLK

13Y/BLK

13U/BLK

13S/BLK

1/RED

IGNITION

SWITCH

S--3

1D/RED

12V

540 C.C.A.

BATT.

ACC

START

13/BLK

BATTERY

18A/

ORA

30 M3

22/

YEL

20/BLU

CB--1

15A

19/BLU

23/GRY

13D/BLK

5.0A

CB--6

1E/RED

ELECTRICAL

4-66 7400 MM428 (12--98)

DOES THE LIGHT TURN

ON MOMENTARILY AT

POWER UP ?

OPERATION:

--WHEN S--14 CLOSES, LIGHT

TURNS ON

--THIS LIGHT IS AN OPTION

HYDRAULIC (HIGH) PRESSURE

INDICATOR LIGHT WILL NOT TURN ON

(FLOW CHART)

YES

REPLACE LAMP L5

INSIDE PANEL,

THEN RETEST

DOES THE LIGHT TURN

ON MOMENTARILY AT

POWER UP ?

REPLACE INSTR. PANEL

DISCONNECT S--14 AND

GROUND WIRE 35/BRN

DOES THE LIGHT COME

ON ?

YES NO

WIRE 35/BRN IS OPENREPLACE S--14

--DISCONNECT S--14

--DISCONNECT INSTR.

PANEL

CHECK CONTINUITY

35/BRN TO GROUND

OPERATION:

--WHEN S--14 CLOSES, LIGHT

TURNS ON

--THIS LIGHT IS AN OPTION

HYDRAULIC (HIGH) PRESSURE

INDICATOR LIGHT WILL NOT TURN OFF

(FLOW CHART)

YES

KEY ON

ENGINE OFF

DISCONNECT S--14

DOES LIGHT TURN

OFF ?

IF HYDRAULIC SYSTEM OK

REPLACE S--14

POWER OFF

OPEN

CONTINUITY

REPLACE INSTR. PANEL

35/BRN IS SHORTED

TO GROUND

REPAIR AND RE-

PLACE 35/BRN

ELECTRICAL

4-67

7400 MM428 (12--98)

OPERATION:

--(PIN 15) IS PULLED TO GROUND

WHEN OIL PRESSURE IS HIGH ENOUGH

--OIL LIGHT TURNS OFF

ENGINE OIL PRESSURE WARNING

LIGHT WILL NOT TURN ON OR OFF

(SCHEMATIC)

5 SEC. DELAY

ES PUMP RUNS

30 SEC.

5 SEC. DELAY

1MIN.TOVAC

FAN SHUT--OFF

13K/BLK

23C/GRY

27/PUR

26/BRN

RECOVERY

TANK

SOLUTION

TANK

S--18 N.C.H.O.

S--17 N.O.H.C.

N.C.H.O.

28/YEL

57/GRN

ES PUMP

85 86

RECOVERY TANK

S--8

IGNITION

SWITCH

S--3

13J/BLK

1D/RED

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

13T/BLK 13Y/BLK

CB--1

15A

15B/BLU

15/BLU

14/GRN

18A/ORA 13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

1/RED 13/BLK

BATTERY

13U/BLK

18A/ORA

23/GRY

18A/

ORA

8730

22/

YEL

85 M3

1E/

RED

19/BLU 13D/BLK

13S/BLK

23/GRY

15/BLU

ELECTRICAL

4-68 7400 MM428 (12--98)

(PIN 15) IS GROUNDED

CHECK OIL PRESSURE

SWITCH OPERATION

DOES OIL LIGHT TURN

ON MOMENTARILY AT

POWER UP ?

OPERATION:

--(PIN 15) IS PULLED TO GROUND

WHEN OIL PRESSURE IS HIGH ENOUGH

--OIL LIGHT TURNS OFF

ENGINE OIL PRESSURE WARNING

LIGHT WILL NOT TURN ON

(FLOW CHART)

YES

REPLACE LAMP L1

INSIDE PANEL

STILL NOT TURNING

ON AT POWER UP

REPLACE INSTR. PANEL

DISCONNECT OIL PRESSURE

SWITCH S--4

GROUND WIRE 15/BLU

DOES LIGHT SHUT OFF ?

OPERATION:

--(PIN 15) IS PULLED TO GROUND

WHEN OIL PRESSURE IS HIGH ENOUGH

--OIL LIGHT TURNS OFF

ENGINE OIL PRESSURE WARNING

LIGHT WILL NOT TURN OFF

(FLOW CHART)

YES

KEY ON

ENGINE OFF

REPLACE OIL PRESSURE LIGHT

WIRE 15/BLU IS OPEN

FROM OIL PRES-

SURE SWITCH TO

(PIN 15)

ELECTRICAL

4-69

7400 MM428 (12--98)

OPERATION:

--IF S--8 CLOSES, THE RECOVERY TANK

IS FULL

--THE RECOVERY TANK LIGHT COMES ON

--SCRUB , SQUEEGEE, AND VACUUM FAN

TURNS OFF

RECOVERY TANK FULL LIGHT

WILL NOT TURN ON OR OFF

(SCHEMATIC)

5 SEC. DELAY

1MIN.TOVAC

FAN SHUT--OFF

23C/GRY

N.C.H.O.

28/YEL

57/GRN

ES PUMP

85 86

RECOVERY TANK

S--8

IGNITION

SWITCH

S--3

13J/BLK

1D/RED

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

13T/BLK 13Y/BLK

CB--1

15A

15B/BLU

15/BLU

14/GRN

18A/ORA 13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

1/RED 13/BLK

BATTERY

13U/BLK

18A/ORA

23/GRY

18A/

ORA

8730 M3

22/

YEL

85 M3

1E/

RED

19/BLU 13D/BLK

13S/BLK

23/GRY

15/BLU

ELECTRICAL

4-70 7400 MM428 (12--98)

-- P O W E R O F F

--DISCONNECT INSTR. PANEL

DISCONNECT S--8

CHECK CONTINUITY FROM WIRE

28/YEL TO GROUND

IF THE LIGHT IS STILL

NOT TURNING ON MO-

MENTARILY AT POWER

UP----REPLACE THE PANEL

OPERATION:

--IF S--8 CLOSES, THE RECOVERY TANK

IS FULL

--THE RECOVERY TANK LIGHT COMES ON

--SCRUB , SQUEEGEE, AND VACUUM FAN

TURNS OFF

RECOVERY TANK FULL LIGHT

WILL NOT TURN ON

(FLOW CHART)

YES

DOES THE LIGHT TURN ON

MOMENTARILY AT POWER UP ?

REPLACE LAMP L4

INSIDE THE PANEL

DISCONNECT S--8 GROUND WIRE

28/YEL DOES THE LIGHT TURN ON ?

YES NO

WIRE 28/YEL IS OPEN

FROM S--8 TO PANEL

(PIN 10)

WHEN RECOVERY TANK

IS FULL, S--8 IS NOT CLOSING

OR 13J/BLK IS OPEN

OPERATION:

--IF S--8 CLOSES, THE RECOVERY TANK

IS FULL

--THE RECOVERY TANK LIGHT COMES ON

--SCRUB , SQUEEGEE, AND VACUUM FAN

TURNS OFF

RECOVERY TANK FULL LIGHT

WILL NOT TURN OFF

(FLOW CHART)

DISCONNECT S--8

DOES THE LIGHT TURN OFF ?

YES NO

RECOVERYTANKISFULL

SYSTEM OK, OR

S--8 IS SHORTED

OPEN CONTINUITY

REPLACE INSTR.

PANEL

WIRE 28/YEL IS

GROUNDED

ELECTRICAL

4-71

7400 MM428 (12--98)

42A/YEL

42/YEL

13 GAS--DIESEL

13L/BLK

FUEL SENDER

SE--1

OPERATION:

--S--6 IS NOT ON MACHINE

--SE--1 GREATER THE 90 OHMS=FULL TANK

--SE--1 LESS THAN 10 OHMS=EMPTY TANK

FUEL GAUGE (GAS AND DIESEL)

(SCHEMATIC)

23C/GRY M5

57/GRN

ES PUMP

85 86

IGNITION

SWITCH

S--3

1D/RED

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

13T/BLK 13Y/BLK

CB--1

15A

15B/BLU

15/BLU

14/GRN

18A/ORA 13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

1/RED 13/BLK

BATTERY

13U/BLK

18A/ORA

23/GRY

18A/

ORA

8730

22/

YEL

8685 M3

1E/

RED

19/BLU 13D/BLK

13S/BLK

23/GRY

15/BLU

ELECTRICAL

4-72 7400 MM428 (12--98)

42/YEL IS SHORTED

TO GROUND

-- P O W E R O F F

--DISCONNECT SE--1

--DISCONNECT INSTR. PANEL

CHECK CONTINUITY OF WIRE

42A/YEL TO GROUND

GROUND 42A/YEL AT SE--1

IS GAUGE FULL ON ?

REPLACE INSTR.

PANEL

IF GAUGE IS INACCURATE

REPLACE THE FLOAT

DISCONNECT 42A/YEL AT SE--1

IS GAUGE FULL ON ?

OPERATION:

--S--6 IS NOT ON MACHINE

--SE--1 GREATER THE 90 OHMS=FULL TANK

--SE--1 LESS THAN 10 OHMS=EMPTY TANK

FUEL GAUGE (GAS AND DIESEL)

(FLOW CHART)

YES

KEY ON

ENGINE OFF

NO YES

GAUGE STILL

WAY OFF

REPLACE INSTR.

PANEL

REPLACE INSTR.

PANEL

OPEN CONTINUITY

CHECK CONTINUITY

OF 42/YEL

OPEN

REPAIR 42/YEL

ELECTRICAL

4-73

7400 MM428 (12--98)

OPERATION:

--S--6ISOPEN=GAUGEISOFF

--S--6 IS CLOSED = LEFT 2 SEGMENTS OF

GAUGE FLASH

--SE--1 IS NOT ON MACHINE

FUEL GAUGE (LPG)

(SCHEMATIC)

42B/YEL

42/YEL

13M/BLK

LP CLOSES BELOW

40 PSI

N.C.H.O.

S--6

23C/GRY M5

57/GRN

ES PUMP

85 86

IGNITION

SWITCH

S--3

1D/RED

20/BLU

ELECTRONIC

INSTRUMENT

PANEL

BATT.

ACC

START

13T/BLK 13Y/BLK

CB--1

15A

15B/BLU

15/BLU

14/GRN

18A/ORA 13P/BLK

13B/BLK

S--4 OIL SWITCH

15A/BLU

FUEL PUMP

10A/GRY

1/RED 13/BLK

BATTERY

13U/BLK

18A/ORA

23/GRY

18A/

ORA

8730

22/

YEL

8685 M3

1E/

RED

19/BLU

13D/BLK

13S/BLK

23/GRY

15/BLU

ELECTRICAL

4-74 7400 MM428 (12--98)

42/YEL IS SHORTED

TO GROUND

-- P O W E R O F F

--DISCONNECT PANEL

--DISCONNECT S--6

CHECK CONTINUITY OF

42B/YEL TO GROUND

-- P O W E R O F F

CHECK CONTINUITY OF 42B/YEL

FROM S--6 TO PANEL (PIN 13)

IF SYSTEM IS NOT

WORKING PROPERLY----

REPLACE S--6

GROUND 42B/YEL AT S--6

IS GAUGE FLASHING ?

OPERATION:

--S--6ISOPEN=GAUGEISOFF

--S--6 IS CLOSED = LEFT 2 SEGMENTS OF

GAUGE FLASH

--SE--1 IS NOT ON MACHINE

FUEL GAUGE (LPG)

(FLOW CHART)

YES

KEY ON

ENGINE OFF

DISCONNECT S--6

IS GAUGE OFF ?

YES

OPEN CONTINUITY

REPLACE INSTR.

PANEL

REPAIR 42 /YEL

CONTINUITY

OPEN

REPLACE INSTR.

PANEL

HYDRAULICS

5-1

7400 MM428 (6--01)

CONTENTS

Page

HYDRAULIC FLUID RESERVOIR 5-3..........

HYDRAULIC FLUID 5-3......................

HYDRAULIC HOSES 5-4.....................

TO REPLACE DIRECTIONAL PEDAL

CENTERING SPRING 5-5.................

TO REPLACE DIRECTIONAL

CONTROL CABLE 5-7....................

TO ADJUST CENTERING SPRING 5-9.....

TO REPLACE PROPEL PUMP 5-10...........

TO REPLACE ACCESSORY PUMP 5-12.......

TO REPLACE STEERING CYLINDER 5-14.....

TO REPLACE HYDRAULIC STEERING

VALVE 5-15..............................

TO REPLACE MAIN HYDRAULIC VALVE 5-16..

TO REPLACE SIDE BRUSH HYDRAULIC

VALVE 5-18..............................

TO REPLACE SOLENOID VALVE

CARTRIDGE 5-20........................

TO REPLACE ENGINE COOLING FAN

HYDRAULIC MOTOR 5-22.................

TO REPLACE MAIN SCRUB BRUSH

HYDRAULIC MOTORS 5-24...............

TO REPLACE SCRUB HEAD ASSEMBLY

LIFT CYLINDER 5-27.....................

TO REPLACE OPTIONAL SIDE BRUSH

HYDRAULIC MOTOR 5-28.................

TO REPLACE OPTIONAL SIDE BRUSH

LIFT CYLINDER 5-29.....................

TO REPLACE OPTIONAL SIDE BRUSH

SWING CYLINDER 5-30...................

TO REPLACE SQUEEGEE LIFT

CYLINDER 5-31..........................

TO REPLACE VACUUM FAN HYDRAULIC

MOTOR 5-32.............................

HYDRAULIC SCHEMATIC 5-35...............

HYDRAULIC HOSE GROUP 5-37.............

HYDRAULIC HOSE GROUP/SIDE BRUSH

OPTION 5-38............................

TROUBLESHOOTING 5-39...................

ENGINE FAN CIRCUIT (SCHEMATIC) 5--40.

ENGINE FAN SLOW OR DOESN’T RUN

(FLOW CHART) 5--41..................

ENGINE FAN MOTOR SHAFT SEAL

LEAKS (FLOW CHART) 5--42...........

MAIN BRUSH ON CIRCUIT

(SCHEMATIC) 5--44...................

MAIN BRUSHES DO NOT TURN ON

(FLOW CHART) 5--45..................

MAIN BRUSHES DO NOT TURN OFF

(FLOW CHART) 5--46..................

Page

MAIN BRUSHES DO NOT LOWER

(FLOW CHART) 5--49..................

MAIN BRUSH LIFT CIRCUIT

(SCHEMATIC) 5--50...................

MAIN BRUSH LOWER CIRCUIT

(SCHEMATIC) 5--48...................

MAIN BRUSHES DO NOT RAISE

(FLOW CHART) 5--51..................

MAIN BRUSHES DO NOT STAY UP

(FLOW CHART) 5--52..................

SCRUB FAN CIRCUIT

(SCHEMATIC) 5--54...................

SCRUB FAN DOES NOT TURN ON

(FLOW CHART) 5--55..................

SCRUB FAN DOES NOT TURN OFF

(FLOW CHART) 5--56..................

SCRUB FAN MOTOR SHAFT SEAL

LEAKS (FLOW CHART) 5--57...........

MAIN BRUSH ON CIRCUIT

(SCHEMATIC) 5--58...................

SIDE BRUSH DOES NOT TURN ON

(FLOW CHART) 5--59..................

SIDE BRUSH DOES NOT TURN OFF

(FLOW CHART) 5--60..................

SIDE BRUSH EXTEND CIRCUIT

(SCHEMATIC) 5--62...................

SIDE BRUSH DOES NOT GO OUT

(FLOW CHART) 5--63..................

SIDE BRUSH DOES NOT GO IN

(FLOW CHART) 5--64..................

SIDE BRUSH LOWER CIRCUIT

(SCHEMATIC) 5--66...................

SIDE BRUSH DOES NOT STAY UP

(FLOW CHART) 5--67..................

SIDE BRUSH DOES NOT RAISE

(FLOW CHART) 5--68..................

SIDE BRUSH DOES NOT LOWER

(FLOW CHART) 5--69..................

SQUEEGEE LIFT CIRCUIT

(SCHEMATIC) 5--70...................

SQUEEGEE DOES NOT LOWER

(FLOW CHART) 5--71..................

SQUEEGEE DOES NOT RAISE

(FLOW CHART) 5--72..................

SQUEEGEE DOES NOT STAY UP

(FLOW CHART) 5--73..................

STEERING CIRCUIT (SCHEMATIC) 5--74...

EATON HYDRAULICS REPAIR

MANUAL 5--75........................

HYDRAULICS

5-2 7400 MM428 (12--98)

HYDRAULICS

5-3

7400 MM428 (12--98)

INTRODUCTION

The hydraulic system consists of the propel pump,

accessory pump, control valve, drive motors,

steering cylinder, and vacuum fan motor.

HYDRAULICS

5-4 7400 MM428 (12--98)

HYDRAULIC FLUID RESERVOIR

The reservoir is located in the front left corner of

the machine.

Mounted on top of the reservoir is a filler cap with

a built-in breather and fluid level dipstick. Replace

the cap every 800 hours of operation.

Check the hydraulic fluid level at operating

temperature every 100 hours of operation. Make

sure the hopper is down when checking hydraulic

fluid level. The end of the dipstick is marked with

FULL and ADD levels to indicate the level of

hydraulic fluid in the reservoir.

Lubricate the filler cap gasket with a film of

hydraulic fluid before putting the cap back on the

reservoir.

ATTENTION! Do not overfill the

hydraulic fluid reservoir or operate the

machine with a low level of hydraulic

fluid in the reservoir. Damage to the

machine hydraulic system may result.

Drain and refill the hydraulic fluid reservoir with

new hydraulic fluid every 800 hours of operation.

The hydraulic fluid filter is located at the bottom of

the engine compartment. Replace the filter

element every 800 hours of operation.

The reservoir has a built-in strainer outlet that

filters hydraulic fluid before it enters the system.

Replace the strainer every 800 hours of operation.

HYDRAULIC FLUID

The quality and condition of the hydraulic fluid

play a very important role in how well the machine

operates. Tennant’s hydraulic fluid is specially

selected to meet the needs of Tennant machines.

Tennant’s hydraulic fluids provide a longer life for

the hydraulic components. There are two fluids

available for different temperature ranges:

Tennant part no. Ambient Temperature

65869 above 7_C(45_F)

65870 below 7_C(45_F)

HYDRAULICS

5-5

7400 MM428 (12--98)

The higher temperature fluid has a higher

viscosity and should not be used at the lower

temperatures. Damage to the hydraulic pumps

may occur because of improper lubrication.

The lower temperature fluid is a thinner fluid for

colder temperatures.

If a locally-available hydraulic fluid is used, make

sure the specifications match Tennant hydraulic

fluid specifications. Using substitute fluids can

cause premature failure of hydraulic components.

European manufactured machines are filled with

locally available hydraulic fluids. Check the label

on the hydraulic fluid reservoir.

ATTENTION! Hydraulic components

depend on system hydraulic fluid for

internal lubrication. Malfunctions,

accelerated wear, and damage will result

if dirt or other contaminants enter the

hydraulic system.

HYDRAULIC HOSES

Check the hydraulic hoses every 800 hours of

operation for wear or damage.

Fluid escaping at high pressure from a very

small hole can be almost invisible, and can cause

serious injuries.

See a doctor at once if injury results from

escaping hydraulic fluid. Serious infection or

reaction can develop if proper medical treatment

is not given immediately.

FOR SAFETY: When servicing machine,

use cardboard to locate leaking

hydraulic fluid under pressure.

If you discover a fluid leak, contact your

mechanic/supervisor.

HYDRAULICS

5-6 7400 MM428 (12--98)

TO REPLACE DIRECTIONAL PEDAL

CENTERING SPRING

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Pivot the operators seat to the open position

and engage the prop rod.

2. Disconnect the battery cables and remove

the battery.

3. Locate the pedal centering spring on the

right side of the accessory pump.

4. Remove the nyloc nut holding the centering

spring balljoint to directional control arm on

the propel pump.

5. Loosen the large jam nut holding the

centering spring to the propel bracket.

6. Remove the spring assembly from bracket

and position it up in the seat support area for

disassembly access.

7. Remove the ball joint and jam nuts.

8. Unscrew the centering spring assembly from

the directional control cable. Discard the old

spring.

NOTE: The cable will have to be held to keep it

from turning

9. Thread a new centering spring assembly all

the way back on the directional control

cable. Leave 1/4 in. of threads showing on

the larger diameter threads on the cable.

10. Install two 1/4 in. jam nuts on the end of the

cable. Tighten one to the centering spring

housing and the other one to the balljoint.

Leave 1/16 in. between the two jam nuts.

11. Use the large jam nut to lock the centering

spring assembly in place.

HYDRAULICS

5-7

7400 MM428 (12--98)

12. Reinstall the spring assembly balljoint back

in the directional control arm. Tighten the

nyloc nut to 11 -- 14 Nm (7 -- 10 ft lb).

13. Reinstall the battery and reconnect the

battery cables.

14. Jack up the front of the machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack stands

15. Check neutral centering of pump by starting

machine and observing front tire for any

rotation. If tire is rotating See TO ADJUST

CENTERING SPRING instructions.

16. Once the neutral centering has been set,

remove the jack stands, lower the machine,

and close the operators seat.

HYDRAULICS

5-8 7400 MM428 (12--98)

TO REPLACE DIRECTIONAL CONTROL

CABLE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Pivot the operators seat to the open position

and engage the prop rod.

2. Disconnect the battery cables and remove

the battery.

3. Locate the pedal centering spring on the

right side of the accessory pump.

4. Remove the hex screw and nyloc nut

holding the centering spring balljoint to

directional control arm on the propel pump.

Retain the two steel sleeves.

5. Loosen the large jam nut holding the

centering spring to the propel bracket.

6. Remove the spring assembly from the

mount bracket and position it up in the seat

support area for disassembly access.

7. Remove the ball joint and jam nuts.

8. Unscrew the centering spring assembly from

the directional control cable. Retain the old

centering spring.

NOTE: The cable will have to be held to keep it

from turning

9. Remove the two hex screw holding the floor

plate in the operators compartment. Remove

the floor plate.

10. Remove the clamp holding the directional

cable to the operators compartment.

11. Reach in through the floor plate opening and

remove the nyloc nut holding the directional

control cable ball joint to the forward reverse

pedal arm. Pull the directional control cable

ball joint out of the pedal arm.

12. Loosen the large jam nut on the directional

control cable. Drop the cable out of the slot.

Remove the cable from the machine.

HYDRAULICS

5-9

7400 MM428 (12--98)

13. Install the old centering spring assembly all

the way back on the new directional control

cable. Leave 1/4 in. of threads showing on

the larger diameter threads on the cable.

14. Install two 1/4 in. jam nuts on the end of the

cable. Tighten one to the centering spring

housing and the other one to the balljoint.

Leave 1/16 in. between the two jam nuts.

15. Reinstall the centering spring/directional

cable assembly back in the machine.

16. Use the large jam nut to lock the centering

spring assembly in place on the mount

bracket.

17. Reinstall the spring assembly balljoint back

on the directional control arm. Reinstall the

hex screw, two steel sleeves, and nyloc nut.

Tighten to 11 -- 14 Nm (7 -- 10 ft lb).

18. Reach in through the floor plate opening and

reinstall the cable ball joint in the forward

reverse pedal arm. Reinstall the nyloc nut

and tighten to 11 -- 14 Nm (7 -- 10 ft lb).

19. Use the large jam nut to lock the directional

cable in place on the mount bracket.

20. Reinstall the cable clamp that holds the

directional cable to the operators

compartment.

21. Reinstall the battery and reconnect the

battery cables.

22. Jack up the front of the machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

23. Check neutral centering of pump by starting

machine and observing front tire for any

rotation. If tire is rotating See TO ADJUST

CENTERING SPRING instructions.

24. Once the neutral centering has been set,

remove the jack stands, lower the machine,

and close the operators seat.

HYDRAULICS

5-10 7400 MM428 (12--98)

TO ADJUST CENTERING SPRING

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine.

1. Jack up the front of the machine.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack stands

2. Check the neutral centering of the pump by

starting the machine and observing the front

tire for any rotation.

3. If tire is rotating, shut off the engine. Pivot

the operators seat to the open position and

engage the prop rod.

4. Locate the centering spring adjustment

bracket on the right side of the accessory

pump. Loosen the two M6 hex screws on

top of the bracket.

5. Loosen the two jam nuts on the hex screw

that is used to move the adjustment bracket

back and forth.

6. Start the machine and observe the front tire

for any rotation. If the tire is rotating in

either direction, move the adjustment

bracket backward or forward until rotation

stops. Re--tighten the two jam nuts. Shut off

the engine.

7. Once all the rotation has been eliminated,

tighten the two M6 hex screws that hold the

two brackets together. Tighten to

11 -- 1 4 N m ( 7 -- 1 0 f t l b ) .

8. Lower the operators seat.

9. Remove the jack stands and lower the

machine to the ground.

HYDRAULICS

5-11

7400 MM428 (12--98)

TO REPLACE PROPEL PUMP

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Pivot the operators seat to the open position

and engage the prop rod.

2. Disconnect the battery cables and remove

the battery.

NOTE: The battery tray can also be removed for

better access to the propel pump

3. Remove the detergent tank and the rubber

sound flap from the machine.

4. Disconnect the tension spring leading from

the directional spring bracket to the brush

wrap.

5. Remove the two hex screws holding the

accessory pump to the propel pump.

6. Lift the directional spring bracket up far

enough to allow accessory pump removal.

NOTE: The main suction line to the accessory

pump is held, by plastic ties, in a bundle of hoses

near the main valve. Remove the plastic ties to

gain slack in the suction line to ease pump

removal.

7. The accessory pump can now be pulled out

of the propel pump. Do not disconnect the

hydraulic hoses leading to the accessory

pump.

8. Mark, remove, and plug the hydraulic hoses

leading to the propel pump.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

9. Remove the one socket screw holding the

propel pump directional arm and hub to the

pump shaft. Remove the hub and arm from

the pump.

NOTE: The pump shaft is tapered so the hub may

need to be removed with a puller.

10. Remove the two hex screws holding the

propel pump to the engine bellhousing.

HYDRAULICS

5-12 7400 MM428 (12--98)

11. Pull the propel pump out of the bellhousing

and drive coupler. Remove the pump from

the machine.

12. Remove the fittings from the old propel

pump and install in the new pump in the

same orientation.

13. Place grease on the splines of the new

pump and install back in the machine.

14. Reinstall the two hex screws and washers.

Use a small amount of blue loctite 242 on

the threads. Tighten to 31 -- 40 Nm

(27 -- 35 ft lb).

15. Reinstall the propel pump directional arm

and hub to the pump shaft. Reinstall the

socket screw. Tighten to 18 -- 24 Nm

(15 -- 20 ft lb).

16. Reconnect the hydraulic hoses to the propel

pump. See the schematic in this section.

17. Reinstall the accessory pump in the back of

the propel pump. Make sure the O--ring is in

place on the accessory pump.

18. Place the directional spring bracket back on

the flange of the accessory pump.

19. Reinstall the two hex screws and washers.

Use a small amount of blue loctite 242 on

the threads. Tighten to 31 -- 40 Nm

(27 -- 35 ft lb).

20. Reconnect the tension spring to the brush

wrap and directional spring bracket.

21. Reinstall the detergent tank in the seat

support area.

22. Reinstall the battery and reconnect the

battery cables.

23. Start the machine. Check the propel pump

for leaks and proper operation.

HYDRAULICS

5-13

7400 MM428 (12--98)

TO REPLACE ACCESSORY PUMP

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Pivot the operators seat to the open position

and engage the prop rod.

2. Disconnect the battery cables and remove

the battery.

3. Remove the detergent tank from the

machine.

4. Disconnect the tension spring leading from

the directional spring bracket to the brush

wrap.

5. Mark, remove, and plug the hydraulic hoses

leading to the accessory pump.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

6. Remove the two hex screws holding the

accessory pump to the propel pump.

7. Lift the directional spring bracket up far

enough to allow accessory pump removal.

8. The accessory pump can now be pulled

back out of the propel pump. Remove the

accessory pump from the machine.

9. Remove the fittings from the old accessory

pump and install in the new pump in the

same orientation.

10. Place grease on the splines of the new

pump and install back in the machine.

11. Position the accessory pump back in the

propel pump. Make sure the O--ring is in

place on the accessory pump.

HYDRAULICS

5-14 7400 MM428 (12--98)

12. Reinstall the two hex screws and washers.

Use a small amount of blue loctite 242 on

the threads. Place the directional spring

bracket back under the bolt heads. Tighten

to 31 -- 40 Nm (27 -- 35 ft lb).

13. Reconnect the hydraulic hoses to the

accessory pump. See the schematic in this

section.

14. Reconnect the tension spring to the brush

wrap and directional spring bracket.

15. Reinstall the detergent tank in the seat

support area.

16. Reinstall the battery and reconnect the

battery cables.

17. Start the machine. Check the accessory

pump for leaks and proper operation.

TO REPLACE STEERING CYLINDER

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Turn the steering wheel to the left and open

the machine front cover.

2. Mark, remove, and plug the two hydraulic

hoses leading to the steering cylinder.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

HYDRAULICS

5-15

7400 MM428 (12--98)

3. Remove the clamp holding the drive motor

hoses to the drive motor casting. Move the

hoses to gain access to steering cylinder

attachment hardware.

4. Remove the large hex screw and nyloc nut

holding the rod end of the steering cylinder

to drive motor casting. Retain the spacer

under the ball end.

5. Remove the large hex screw and nyloc nut

holding the piston end of the steering

cylinder to the machine frame.

6. Remove the steering cylinder from the

machine.

7. Remove the fittings from the old cylinder and

install in the new cylinder in the same

orientation.

8. Position new cylinder and balljoint assembly

back in the machine with rod end pointed

toward the drive motor casting.

9. Reinstall the hex screw, spacer, and nyloc

nut in the rod end of the steering cylinder

and through the drive motor casting. Tighten

to 271 Nm (200 ft lb).

10. Reinstall the hex screw and nyloc nut in the

piston end of the steering cylinder and

through the machine frame. Tighten to

271 Nm (200 ft lb).

11. Reconnect the hydraulic hoses to the

steering cylinder. See schematic in this

section.

12. Reinstall the clamp holding the drive motor

hoses to the front casting. Tighten the

hardware to 18 -- 24 Nm (15 -- 20 ft lb).

13. Start the machine and operate the steering.

Check for any leaks and proper operation.

Close the front cover.

HYDRAULICS

5-16 7400 MM428 (12--98)

TO REPLACE HYDRAULIC STEERING VALVE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Open the machine front cover.

2. Mark, remove, and plug the five hydraulic

hoses leading to the steering control valve.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

3. Remove the four M6 hex screws holding the

steering control valve to the steering

column.

4. Pull the steering valve out of the steering

column and remove it from the machine.

5. Remove the hydraulic fittings from old

control valve and install in the new valve in

the same orientation.

6. Install the new steering valve back in the

machine. Position the ports in the same

orientation as the old valve. Reinstall the

four M6 hex screws and tighten to

8--10Nm(5--7ftlb).

7. Reconnect hydraulic hoses to steering valve.

See schematic in this section.

8. Start the machine and operate the steering.

Check for any leaks and proper operation.

HYDRAULICS

5-17

7400 MM428 (12--98)

TO REPLACE MAIN HYDRAULIC VALVE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

3. If the machine is an LPG, remove the LP

tank from the cradle.

4. Locate the main hydraulic valve under the

vacuum fan. Disconnect the 7 electrical

solenoids on the main valve from the main

harness.

5. Mark, remove, and plug the hydraulic hoses

leading to the main hydraulic valve.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

6. Remove the three M8 hex screws holding

the main valve to the machine frame.

7. The main valve can now be removed from

the machine.

8. Remove the hex screws holding the main

valve to the mount bracket.

9. Remove hydraulic fittings from the old valve

and install in the new valve in the same

orientation.

10. Reinstall the mount bracket on the new

valve. Reinstall the three M8 hex screws

and washers. Tighten to 18 -- 24 Nm

(15 -- 20 ft lb).

HYDRAULICS

5-18 7400 MM428 (12--98)

11. Position the new valve back in the machine.

Reinstall the three M8 hex screws and

washers. Tighten to 18 -- 24 Nm

(15 -- 20 ft lb).

12. Reconnect the hydraulic hoses to the main

valve. See schematic in this section.

13. Reconnect the 7 electric solenoids to the

main harness. See ELECTRICAL section.

14. Reinstall the LP tank.

15. Reinstall the engine side door.

16. Reconnect the battery cables and close the

operators seat.

17. Start the machine and check the main valve

for any leaks.

HYDRAULICS

5-19

7400 MM428 (12--98)

TO REPLACE SIDE BRUSH HYDRAULIC

VALVE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

3. If the machine is an LPG, remove the LP

tank from the cradle.

4. Locate the side brush hydraulic valve under

the LP/gas tank cradle. Disconnect the 4

electrical solenoids from the main harness.

5. Mark, remove, and plug the hydraulic hoses

leading to the side brush valve.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

6. Remove the three M8 hex screws holding

the side brush valve to the LP tank cradle.

7. The side brush valve can now be removed

from the machine.

8. Remove hydraulic fittings from the old valve

and install in the new valve in the same

orientation.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

9. Position the new valve back in the machine.

Reinstall the three M8 hex screws and

washers. Tighten to 18 -- 24 Nm

(15 -- 20 ft lb).

DR2

C7 C6

HYDRAULICS

5-20 7400 MM428 (12--98)

10. Reconnect the hydraulic hoses to the side

brush valve. See schematic in this section.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

11. Reconnect the 4 electric solenoids to the

main harness. See ELECTRICAL section.

12. Reinstall the LP tank.

13. Reinstall the engine side door.

14. Reconnect the battery cables and close the

operators seat.

15. Start the machine and check the side brush

valve for any leaks.

HYDRAULICS

5-21

7400 MM428 (12--98)

TO REPLACE SOLENOID VALVE CARTRIDGE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

3. If the machine is an LPG, remove the LP

tank from the cradle.

4. Locate and identify the cartridge to be

removed. Unplug the solenoid from the main

harness.

5. Remove the hex nut and rubber O--ring from

the cartridge stem.

NOTE: The port marked SV--4 on the main valve

and the port marked SV--10 on the side brush

valve contain an extra washer on the cartridge

stem between the top nut and O--ring.

6. Slide the electrical coil and rubber o--ring off

the stem.

NOTE: Oil will run out of valve when the

cartridge is removed.

7. Loosen and unscrew the cartridge stem out

of the valve body.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

8. Install a new or rebuilt cartridge stem back in

the port. Tighten to 47 Nm (35 ft lb).

NOTE: Make sure the new cartridge had an

O--ring installed and oiled.

9. Slip the O--ring and coil back over the stem.

HYDRAULICS

5-22 7400 MM428 (12--98)

10. Install the 0--ring and hex nut on the stem

and tighten to 170 Ncm (15 in lb).

11. Reconnect the coil to the main harness. See

schematic in Electrical section.

12. Reinstall the LP tank.

13. Reinstall the engine side door.

14. Reconnect the battery cables and close the

operators seat.

15. Start the machine and check the side brush

valve for any leaks.

HYDRAULICS

5-23

7400 MM428 (12--98)

TO REPLACE ENGINE COOLING FAN

HYDRAULIC MOTOR

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Open the engine cover and side door.

2. Remove the hose from the vacuum fan and

recovery tank.

3. Remove the air cleaner hose from the air

cleaner and carburetor.

4. Mark, disconnect, and plug the three

hydraulic hoses going to the fan motor.

NOTE: Observe hydraulic cleanliness

requirements when opening hydraulic lines.

5. Remove the hydraulic fittings from the fan

motor. Note the orientation of the fittings for

proper reassembly in the new motor.

6. Reach in through the fan blades and remove

the four M6 hex screws holding the fan

blade to the motor hub. Set the fan blade

down in the fan air chamber.

7. Remove the 5/16 in. nut and washer holding

the fan blade hub to the motor shaft.

Remove the hub from the shaft. Retain the

square key from the motor shaft.

NOTE: The fan blade hub is on a tapered shaft

and may need to be pried off the motor.

8. Remove the two M10 hex screws and nyloc

nuts holding the fan motor to the mount

bracket. Remove the fan motor from the

machine.

9. Install the new fan motor on the mount

bracket. Reinstall the M10 hex screws and

nyloc nuts (nylocs positioned on the motor

side). Tighten to 37 -- 48 Nm (26 -- 34 ft lb).

NOTE: The notch in the mount bracket is for the

motor fitting.

10. Install the square key on the fan motor shaft.

NOTE: A small amount of super glue helps keep

the key in place when installing the fan hub.

HYDRAULICS

5-24 7400 MM428 (12--98)

11. Install the fan hub on the motor shaft.

Reinstall the 5/16 in. nut and tighten to

18 -- 24 Nm (15 -- 20 ft lb).

NOTE: Make sure key is in place on motor shaft.

12. Reinstall the fan blade back on the fan hub.

The deep side of the fan blade points to the

back of the machine. Reinstall the four M6

hex screws and tighten to 7.9 -- 9.9 Nm

(6 -- 7 ft lb).

13. Reinstall the hydraulic fittings in the fan

motor in the same orientation as they were

removed.

14. Reconnect the hydraulic hoses to the fan

motor. See schematic in this section.

15. Reinstall the air cleaner hose and vacuum

fan hose.

16. Reconnect the engine cover outer gas

spring to lower ball.

17. Start machine and check for leaks. Check

the engine fan for proper rotation. (air blows

out the back of machine).

HYDRAULICS

5-25

7400 MM428 (12--98)

TO REPLACE MAIN SCRUB BRUSH

HYDRAULIC MOTORS

1. Place the main scrub brushes in the raised

position.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

2. Open the LH brush door.

3. Remove the front ball joint on the leveling

rod from the machine frame.

4. Remove the two hair pins from the brush

wrap attachment pins.

5. Remove the three hex screws holding the

side squeegee assembly to the motor mount

plate. Remove the side squeegee.

6. Remove the M12 hex screw holding the

brush idler plate arm to the lift tube.

NOTE: For better access to the hydraulic drive

motors----remove the C--clip and brush arm from

the motor plate.

7. Mark, disconnect, and plug the three

hydraulic hoses leading to the main brush

drive motors.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

8. Remove the motor mount plate assembly

from the machine.

9. Turn the motor plate assembly over.

Remove the cotter pins, castle nuts, and

washers from the drive plugs.

10. Use a puller to remove the drive plug from

the brush motors. Remove and retain the

square key.

11. Remove the steel hydraulic tube running

between the brush drive motors.

HYDRAULICS

5-26 7400 MM428 (12--98)

12. Remove the four hex screws holding each

brush motor to the motor plate.

NOTE: Make sure to note the orientation of the

motor and fittings before removing the motors

from the plate.

13. Remove the fittings from the old motor and

install in the new motor in the same

orientation.

14. Install the new brush motor and fittings in

the motor plate in the same orientation as

the old motor.

15. Reinstall the four hex screws and tighten to

37 -- 48 Nm (26 -- 34 ft lb).

16. Reinstall the steel hydraulic tube running

between the brush drive motors.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

17. Reinstall the square key on the tapered

motor shaft. Put a small amount of grease

on the taper of the shaft.

18. Reinstall the drive plugs, washers, and

castle nuts. Hold the plug from turning and

tighten the castle nut down to 37 -- 48 Nm

(26 -- 34 ft lb) and then until the slot in the

nut lines up with the hole in the shaft. Install

a new cotter pin.

19. Position the motor plate assembly back in

the machine.

NOTE: Lift up on the brush wrap slightly when

installing the motor plate in the machine so the

attachment pins line up with the holes in the plate.

20. Reinstall the two hair pins in the brush wrap

attachment pins.

21. Reconnect the hydraulic hoses to the brush

motors. See schematic in this section.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

22. Reinstall the brush arm and C--clip to the

motor plate if they were removed earlier.

23. Align the two pins on the lift tube with the

two holes in the brush arm.

HYDRAULICS

5-27

7400 MM428 (12--98)

24. Reinstall the M12 hex screw in the brush

arm. Tighten to 64 -- 83 Nm (47 -- 61 ft lb).

NOTE: Apply a small amount of grease to the

threads on the bolt and in the tube.

25. Reinstall the front of the leveling rod ball

joint to the machine frame.

26. Reinstall the side squeegee assembly to the

motor plate. Tighten the three hex screws to

37 -- 48 Nm (26 -- 34 ft lb).

27. Close the LH brush door and operate the

machine. Check the main brush motors for

proper operation.

HYDRAULICS

5-28 7400 MM428 (12--98)

TO REPLACE SCRUB HEAD ASSEMBLY

LIFT CYLINDER

1. Start the engine and drop the main scrub

brushes down until they just touch the floor.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

2. Jack up the front of the machine and install

jack stands under the frame.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

3. Go under the machine on the LH side.

4. Locate the lift cylinder on the left side of the

front scrub brush.

5. Mark, disconnect, and plug the two hydraulic

hoses going to the lift cylinder.

6. Remove the two cotter pins and clevis pins.

7. Remove the lift cylinder from the machine.

8. Remove the hydraulic fittings from the lift

cylinder and install in the new cylinder in the

same orientation.

9. Install the new cylinder in the machine.

NOTE: The rod end of the cylinder points down.

10. Reinstall the upper and lower clevis and

cotter pins.

11. Reconnect the hydraulic hoses to the new

lift cylinder. See schematic in this section.

12. Remove the jack stands and lower the

machine.

13. Start the machine and check the scrub head

lift cylinder for proper operation.

HYDRAULICS

5-29

7400 MM428 (12--98)

TO REPLACE OPTIONAL SIDE BRUSH

HYDRAULIC MOTOR

1. Remove the side brush. See TO REPLACE

OPTIONAL SIDE BRUSH instructions in the

SCRUBBING section.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

2. Remove the four hex screws holding the

side brush guard to the machine frame.

3. Remove the hex screw holding the side

brush drive hub to the side brush motor.

Remove the drive hub from the motor.

4. Mark, disconnect, and plug the two hydraulic

hoses going to the side brush motor.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

5. Remove the four hex screws holding the

side brush motor to the mount plate.

6. Lift the motor straight up, tilt back, and

remove it from the side brush assembly.

NOTE: Make sure to note the orientation of the

motor to the mount plate.

7. Remove the hydraulic fittings from the old

motor and install in the new motor in the

same orientation.

8. Position the new motor back in the side

brush assembly.

9. Reinstall the four hex screws and tighten to

37 -- 48 Nm (26 -- 34 ft lb).

10. Reconnect the hydraulic hoses to the motor.

See schematic in this section.

11. Reinstall the drive hub, washers, and hex

screw. Tighten to 18 -- 24 Nm (15 -- 20 ft lb).

12. Reinstall the side brush. See TO REPLACE

OPTIONAL SIDE BRUSH instructions.

13. Reinstall the side brush guard to the

machine frame. Tighten the four hex screws

to 37 -- 48 Nm (26 -- 34 ft lb).

14. Operate the machine and check the side

brush for proper operation.

HYDRAULICS

5-30 7400 MM428 (12--98)

TO REPLACE OPTIONAL SIDE BRUSH LIFT

CYLINDER

1. Remove the side brush. See TO REPLACE

OPTIONAL SIDE BRUSH instructions.

2. Remove the four hex screws holding the

side brush guard to the machine frame.

3. Remove the side brush hydraulic motor. See

TO REPLACE OPTIONAL SIDE BRUSH

HYDRAULIC MOTOR instructions.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

4. Mark, disconnect, and plug the two hydraulic

hoses going to the lift cylinder.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

5. Remove the two cotter pins and clevis pins

holding the lift cylinder to the side brush

assembly. Remove the lift cylinder from the

machine.

NOTE: Make sure to note the orientation of the

cylinder to the mount plate.

6. Remove the hydraulic fittings from the old

cylinder and install in the new cylinder in the

same orientation.

7. Position the new cylinder back in the side

brush assembly.

8. Reconnect the hydraulic hoses to the

cylinder. See schematic in this section.

9. Reinstall the side brush motor in the

machine. See TO REPLACE OPTIONAL

SIDE BRUSH HYDRAULIC MOTOR

instructions.

10. Reinstall the side brush. See TO REPLACE

OPTIONAL SIDE BRUSH instructions in the

SCRUBBING section.

11. Reinstall the side brush guard to the

machine frame. Tighten the four hex screws

to 37 -- 48 Nm (26 -- 34 ft lb).

12. Operate the machine and check the side

brush lift cylinder for proper operation.

HYDRAULICS

5-31

7400 MM428 (12--98)

TO REPLACE OPTIONAL SIDE BRUSH

SWING CYLINDER

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Open the front cover on the machine.

2. Locate the swing cylinder down in front of

the operators compartment.

3. Mark, disconnect, and plug the two hydraulic

hoses going to the swing cylinder.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

4. Remove the cotter pin and clevis pin holding

the rod end of the swing cylinder to the

threaded sleeve and ball joint assembly.

5. Remove the cotter pin and clevis pin holding

the other end of the swing cylinder to the

machine frame.

6. Pull the swing cylinder back out of the

threaded sleeve and remove it from the

machine.

7. Remove the hydraulic fittings from the old

cylinder and install in the new cylinder in the

same orientation.

8. Position the new cylinder back in the side

brush assembly. Position the rod end of the

cylinder back in the threaded sleeve first,

then install the clevis and cotter pin in the

other end.

9. Reinstall the clevis and cotter pin in the rod

end of the swing cylinder and through the

hole in the threaded sleeve.

10. Reconnect the hydraulic hoses to the

cylinder. See schematic in this section.

11. Operate the machine and check the side

brush swing cylinder for proper operation.

HYDRAULICS

5-32 7400 MM428 (12--98)

TO REPLACE SQUEEGEE LIFT CYLINDER

1. Open the debris tray latch and swing the

squeegee assembly out for better access.

2. Start engine, lower rear squeegee, shut off

engine.

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

3. Mark, disconnect, and plug the two hydraulic

hoses going to the squeegee lift cylinder.

NOTE:Observe hydraulic cleanliness

requirements when opening hydraulic lines.

4. Remove the snap retaining ring from the pin

on the debris tray at piston end of the

cylinder.

NOTE: The cylinder pin DOES NOT have a snap

ring grove.

5. Remove the cotter pin and clevis pin from

the rod end of lift cylinder and squeegee lift

bellcrank.

6. The cylinder can now be pulled up and off

the pin and removed from the machine.

7. Remove the hydraulic fittings from the old

cylinder and install in the new cylinder in the

same orientation.

8. Position new cylinder back in the machine.

Place the hole in the piston end of the

cylinder on the pin on the debris tray.

Reinstall the snap ring retainer on the pin.

NOTE: The cylinder pin DOES NOT have a snap

ring grove.

9. Align the hole in rod end of the cylinder with

the hole in squeegee lift bellcrank. Reinstall

the clevis and cotter pin.

10. Reconnect the hydraulic hoses to the

squeegee lift cylinder. See schematic in this

section.

11. Start the machine and raise the squeegee.

Swing the squeegee assembly back in.

Check the lift cylinder for proper operation.

HYDRAULICS

5-33

7400 MM428 (12--98)

TO REPLACE VACUUM FAN HYDRAULIC

MOTOR

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Remove the vacuum fan from the machine.

See TO REMOVE VACUUM FAN

instructions in the SCRUBBING section.

2. Place the vacuum fan assembly in a vice or

some other holding device.

3. Remove the six hex screws holding the front

housing to the rear housing. Remove the the

front housing.

NOTE: Mark the front housing in relation to the

rear housing so it can be re--assembled correctly.

4. Remove the crown nut on the impeller shaft.

Slide the impeller off the shaft.

NOTE: Remove and save the key and any shims

that are on the motor shaft, under the impeller.

5. Turn the housing over and remove the four

nyloc nuts and washers from the motor

mount plate. Remove the motor mount plate

from the housing.

NOTE: Note the orientation of hydraulic motor and

fittings for proper re--assembly.

6. Remove the four flat head screws and nyloc

nuts holding the hydraulic motor to the

mount plate. Remove the old motor.

7. Install the new motor on the plate. Reinstall

the flat head screws. Tighten to 9 -- 13 Nm

(7 -- 10 ft lb).

8. Remove the hydraulic fittings from the old

motor and install in the new motor in the

same orientation.

HYDRAULICS

5-34 7400 MM428 (12--98)

9. Reinstall the motor and mounting plate on

the rear housing. Reinstall the four nyloc

nuts and tighten to 16 -- 22 Nm

(12 -- 16 ft lb).

NOTE: Be sure the square key is on the motor

shaft. Super gluing the key to the shaft helps keep

it in place when installing the impeller.

10. Turn the housing over and reinstall shims,

key, fan impeller, and crown nut. Tighten nut

to 34 -- 47 Nm (25 -- 35 ft lb).

NOTE: Use a small amount of blue loctite 242 on

the motor shaft threads.

11. Reinstall the front housing on the rear

housing. Reinstall the six hex screws and

tighten to 22 -- 27 Nm (16 -- 20 ft lb).

NOTE: Tennant part no. 57543 plastic shims must

be used for proper fan to housing clearance.

Remove these shims after housing hardware has

been tightened.

12. Reinstall the vacuum fan assembly in the

machine. See TO INSTALL VACUUM FAN

instructions in the SCRUBBING section.

HYDRAULICS

5-35

7400 MM428 (6--01)

AB C D EFGH I

HYDRAULIC SCHEMATIC

HYDRAULICS

5-36 7400 MM428 (6--01)

S-- 14

ABCD GHI

HYDRAULIC SCHEMATIC

HYDRAULICS

5-37

7400 MM428 (6--01)

OUT

DR1

P2 M2 P1

Scrub

Brush

Motors

Steering

Valve

Control Valve

Front

Reservoir

Vac Fan

Wheel

Drive

Motor

Flow

Sensor

Switch

Cooling

Fan

Motor

Scrub Head

Lift Cylinder

Rear

SqueegeeLift

Cylinder

Pump

Cooler

Filter

20 21

HYDRAULIC HOSE GROUP

HYDRAULICS

5-38 7400 MM428 (6--01)

DR2

DR1

P2 M2 P1

SIDE

BRUSH

VALVE

VACUUM FAN

MOTOR

MAIN CONTROL

VALVE

SIDE

BRUSH

MOTOR

SIDE

BRUSH

LIFT CYL

SIDE BRUSH

SWING CYL

HYDRAULIC HOSE GROUP / SIDE BRUSH OPTION

HYDRAULICS

5-39

7400 MM428 (12--98)

TROUBLESHOOTING

The following troubleshooting section is organized

with the section of the hydraulic schematic

pertaining to that particular problem first, followed

by the flow chart.

HYDRAULICS

5-40 7400 MM428 (12--98)

ENGINE

FAN

STRAINER

RV7

1160

RV3

3 PSI

RV6

PSI

2400

RPM

3.7 GPM

PSI

ENGINE FAN CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

400 PSI

3.7GPM

HYDRAULICS

5-41

7400 MM428 (12--98)

MOTOR INLET

FLOW OK?

REPAIR OR

REPLACE MOTOR

REPAIR OR

REPLACE STEERING

CONTROL

PUMP OUTLET

FLOW OK?

PLUMBING OK?

REPAIR OR

REPLACE PLUMBING

YES NO

REPAIR OR

REPLACE PUMP

ENGINE FAN SLOW OR DOESN’T RUN

(FLOW CHART)

YES NO

STEERING INLET

PRESSURE OK?

NO YES

HYDRAULICS

5-42 7400 MM428 (12--98)

MOTOR CASE

PRESSURE OK?

< 25 PSI

REPAIR OR

REPLACE MOTOR

REPAIR OR

REPLACE CASE DRAIN

PLUMBING & MOTOR

YES NO

ENGINE FAN MOTOR SHAFT SEAL LEAKS

(FLOW CHART)

HYDRAULICS

5-43

7400 MM428 (12--98)

HYDRAULICS

5-44 7400 MM428 (12--98)

MAIN

BRUSHES

STRAINER FILTER

RV1

RV2

P3 DR1

P1P2

RV3

3 PSI

8.5 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

MAIN BRUSH ON CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

LEVEL #1 800 PSI

LEVEL #2 1000 PSI

LEVEL #3 1300 PSI

8.4 GPM

LEVEL #1 400 PSI

LEVEL #2 550 PSI

LEVEL #3 700 PSI

8.3 GPM

HYDRAULICS

5-45

7400 MM428 (12--98)

SV1 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

REPAIR OR

REPLACE MOTOR

PLUMBING OK?

SV1 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV1

STEM CARTRIDGE

YES

PUMP OUTLET

FLOW OK?

MAIN BRUSHES DO NOT TURN ON

(FLOW CHART)

YES NO

MOTOR INLET

FLOW OK?

YES

REPAIR OR

REPLACE

PLUMBING

YES

REPAIR OR

REPLACE

PUMP

YES

RV1 RELIEF

CARTRIDGE OK?

2500 PSI

REPAIR OR REPLACE

RV1 RELIEF

CARTRIDGE

HYDRAULICS

5-46 7400 MM428 (12--98)

SV1 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

SV1 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV1

STEM CARTRIDGE

YES NO

MAIN BRUSHES DO NOT TURN OFF

(FLOW CHART)

HYDRAULICS

5-47

7400 MM428 (12--98)

HYDRAULICS

5-48 7400 MM428 (12--98)

MAIN BRUSH LIFT

LOWER

MAIN

BRUSHES

STRAINER

RV1

RV2

P3 DR1

P1P2

RV3

3 PSI

8.5 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

MAIN BRUSH LOWER CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

LEVEL #1 350 PSI

LEVEL #2 500 PSI

LEVEL #3 650 PSI

HYDRAULICS

5-49

7400 MM428 (12--98)

SV4, SV5 & SV7

STEMS

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

SV7 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR REPLACE

PR1 STEM

CARTRIDGE

C3 PORT

PRESSURE OK?

460 -- 730 PSI

SV5 STEM

CARTRIDGE

SHIFTING OK?

YES

MAIN BRUSHES DO NOT LOWER

(FLOW CHART)

YES NO

G5 PORT

PRESSURE OK?

300 PSI

YES

G4 PORT

PRESSURE OK?

460 -- 730 PSI

REPAIR OR REPLACE

SV7 STEM

CARTRIDGE

YES

REPAIR OR REPLACE

SV5 STEM

CARTRIDGE

REPLACE

SV4 STEM

CARTRIDGE

HYDRAULICS

5-50 7400 MM428 (12--98)

MAIN BRUSH LIFT

MAIN

BRUSHES

STRAINER

RV1

RV2

P3 DR1

P1P2

RV3

3 PSI

3.7 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

MAIN BRUSH LIFT CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

300 PSI

1.0 GPM WHILE MOVING

(2.0 -- 3.0 SEC)

HYDRAULICS

5-51

7400 MM428 (12--98)

SV5

STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

LIFT

CYLINDER

SEALS OK?

OR1

ORIFICE

PLUGGED?

C3 PORT

PRESSURE OK?

< 25 PSI

PLUMBING

OK?

YES NO

MAIN BRUSHES DO NOT RAISE

(FLOW CHART)

YES NO

G5 PORT

PRESSURE OK?

300 PSI

YES

SV5 STEM

CARTRIDGE

SHIFTING OK?

REPLACE LIFT

CYLINDER

YES

REPAIR OR

REPLACE

PLUMBING

REPAIR OR

REPLACE OR1

ORIFICE

REPAIR OR

REPLACE PR1

STEM CARTRIDGE

YES

REPAIR OR

REPLACE SV5

STEM CARTRIDGE

HYDRAULICS

5-52 7400 MM428 (12--98)

SV7 STEM

CARTRIDGE

MAGNETIZED?

CHECK

ELECTRICAL

SYSTEM

REPAIR OR

REPLACE

PLUMBING

LIFT

CYLINDER

SEALS OK?

SV7 STEM

CARTRIDGE

SHIFTING & SEAT OK?

REPAIR OR

REPLACE SV7 STEM

CARTRIDGE

YES NO

REPLACE

LIFT

CYLINDER

MAIN BRUSHES DO NOT STAY UP

(FLOW CHART)

YES NO

PLUMBING

OK?

NO YES

HYDRAULICS

5-53

7400 MM428 (12--98)

HYDRAULICS

5-54 7400 MM428 (12--98)

STRAINER FILTER

VACUUM FAN

RV1

RV2

P3 DR1

P1P2

RV3

3 PSI

6.7 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

SCRUB FAN CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

1700 PSI

6.3 GPM

11,000 +/-- 1000 RPM

HYDRAULICS

5-55

7400 MM428 (12--98)

SV2 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

REPAIR OR

REPLACE MOTOR

PLUMBING OK?

SV2 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV2

STEM CARTRIDGE

YES

PUMP OUTLET

FLOW OK?

SCRUB FAN DOES NOT TURN ON

(FLOW CHART)

YES NO

MOTOR INLET

FLOW OK?

YES

REPAIR OR

REPLACE

PLUMBING

YES

REPAIR OR

REPLACE

PUMP

YES

RV2 RELIEF

CARTRIDGE OK?

2500 PSI

REPAIR OR REPLACE

RV2 RELIEF

CARTRIDGE

HYDRAULICS

5-56 7400 MM428 (12--98)

SV2 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

SV2 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV2

STEM CARTRIDGE

YES NO

SCRUB FAN DOES NOT TURN OFF

(FLOW CHART)

ROTOR

SPEED

< 200 RPM

SYSTEM

NORMAL

NO YES

HYDRAULICS

5-57

7400 MM428 (12--98)

MOTOR CASE

PRESSURE OK?

< 25 PSI

REPAIR OR

REPLACE MOTOR

REPAIR OR

REPLACE CASE DRAIN

PLUMBING & MOTOR

YES NO

SCRUB FAN MOTOR SHAFT SEAL LEAKS

(FLOW CHART)

HYDRAULICS

5-58 7400 MM428 (12--98)

MAIN

BRUSHES

STRAINER FILTER

RV1

RV2

P3 DR1

P1P2

RV3

3 PSI

8.5 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

MAIN BRUSH ON CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

LEVEL #1 800 PSI

LEVEL #2 1000 PSI

LEVEL #3 1300 PSI

8.4 GPM

LEVEL #1 400 PSI

LEVEL #2 550 PSI

LEVEL #3 700 PSI

8.3 GPM

HYDRAULICS

5-59

7400 MM428 (12--98)

SV6 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

REPAIR OR

REPLACE MOTOR

PLUMBING OK?

SV6 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV6

STEM CARTRIDGE

YES

PUMP OUTLET

FLOW OK?

SIDE BRUSH DOES NOT TURN ON

(FLOW CHART)

YES NO

MOTOR INLET

FLOW OK?

YES

REPAIR OR

REPLACE

PLUMBING

YES

REPAIR OR

REPLACE

PUMP

YES

RV2 RELIEF

CARTRIDGE OK?

2500 PSI

REPAIR OR REPLACE

RV2 RELIEF

CARTRIDGE

HYDRAULICS

5-60 7400 MM428 (12--98)

SV6 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

SV6 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV6

STEM CARTRIDGE

YES NO

SIDE BRUSH DOES NOT TURN OFF

(FLOW CHART)

BRUSH

SPEED

<10RPM

SYSTEM

NORMAL

NO YES

HYDRAULICS

5-61

7400 MM428 (12--98)

HYDRAULICS

5-62 7400 MM428 (12--98)

SIDE BRUSH

LIFT

SIDE BRUSH

EXTEND

SIDE BRUSH

OPTION

STRAINER

RV1

RV2

P3 DR1

P1P2

DR2

P6 P5 G6

SV09

SV11

SV08

SV10

PR2

300

PSI

100--

800

PSI

RV3

3 PSI

SC1

8.5 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

SIDE BRUSH EXTEND CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

(WITH MAIN BRUSHES ON)

300 PSI

1.0 GPM WHILE MOVING

HYDRAULICS

5-63

7400 MM428 (12--98)

SV9

STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

CYLINDER

LINKAGE & SEALS

OK?

REPAIR OR REPLACE

PR2 PRESSURE

CONTROL CARTRIDGE

DR2 PORT

PRESSURE OK?

< 25 PSI

PLUMBING

OK?

YES

SIDE BRUSH DOES NOT GO OUT

(FLOW CHART)

YES NO

C5 PORT

PRESSURE OK?

300 PSI

YES

SV9 STEM

CARTRIDGE

SHIFTING OK?

REPAIR

CYLINDER LINKAGE

OR SEALS

YES

REPAIR OR

REPLACE

PLUMBING

REPAIR OR REPLACE

SV9 STEM

CARTRIDGE

HYDRAULICS

5-64 7400 MM428 (12--98)

SV9

STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

CYLINDER

LINKAGE &

SEALS OK?

OR2

ORIFICE

PLUGGED?

C6 PORT

PRESSURE OK?

< 25 PSI

PLUMBING

OK?

YES NO

SIDE BRUSH DOES NOT GO IN

(FLOW CHART)

YES NO

C5 PORT

PRESSURE OK?

300 PSI

YES

SV9 STEM

CARTRIDGE

SHIFTING OK?

REPAIR CYLINDER

LINKAGE

OR SEALS

YES

REPAIR OR

REPLACE

PLUMBING

REPAIR OR

REPLACE OR2

ORIFICE

SC1 SHUTTLE

CHECK CARTRIDGE

SHIFTING OK?

YES

REPAIR OR

REPLACE SV9

STEM CARTRIDGE

REPAIR OR REPLACE

PR2 PRESSURE

CONTROL CARTRIDGE

REPAIR OR REPLACE

SHUTTLE CHECK

CARTRIDGE

YES NO

HYDRAULICS

5-65

7400 MM428 (12--98)

HYDRAULICS

5-66 7400 MM428 (12--98)

SIDE BRUSH

LIFT

SIDE BRUSH

EXTEND

DOWN

RETRACT

SIDE BRUSH

OPTION

STRAINER

RV1

RV2

P3 DR1

P1P2

DR2

P6 P5 G6

SV09

SV11

SV08

SV10

PR2

300

PSI

100--

800

PSI

RV3

3 PSI

SC1

8.5 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

SIDE BRUSH LOWER CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

(WITH MAIN BRUSHES ON)

LEVEL #1 210 PSI

LEVEL #2 270 PSI

LEVEL #3 320 PSI

1.0 GPM WHILE MOVING

HYDRAULICS

5-67

7400 MM428 (12--98)

SV11 STEM

CARTRIDGE

MAGNETIZED?

CHECK

ELECTRICAL

SYSTEM

REPAIR OR

REPLACE

PLUMBING

LIFT

CYLINDER

SEALS OK?

SV11 STEM

CARTRIDGE

SHIFTING & SEAT OK?

REPAIR OR

REPLACE SV11 STEM

CARTRIDGE

YES NO

REPLACE

LIFT

CYLINDER

SIDE BRUSH DOES NOT STAY UP

(FLOW CHART)

YES NO

PLUMBING

OK?

NO YES

HYDRAULICS

5-68 7400 MM428 (12--98)

SV8

STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

LIFT CYLINDER

LINKAGE & SEALS

OK?

OR2

ORIFICE

PLUGGED?

DR2 PORT

PRESSURE OK?

< 25 PSI

PLUMBING

OK?

YES NO

SIDE BRUSH DOES NOT RAISE

(FLOW CHART)

YES NO

C5 PORT

PRESSURE OK?

300 PSI

YES

SV8 STEM

CARTRIDGE

SHIFTING OK?

REPAIR LINKAGE

OR REPLACE

LIFT CYLINDER

YES

REPAIR OR

REPLACE

PLUMBING

REPAIR OR

REPLACE OR2

ORIFICE

YES

REPAIR OR

REPLACE SV8

STEM CARTRIDGE

SC1 SHUTTLE

CHECK CARTRIDGE

SHIFTING OK?

REPAIR OR REPLACE

PR2 PRESSURE

CONTROL CARTRIDGE

REPAIR OR REPLACE

SHUTTLE CHECK

CARTRIDGE

YES NO

HYDRAULICS

5-69

7400 MM428 (12--98)

SV8, SV10 & SV11

STEMS

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

SV11 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR REPLACE

PR2 PRESSURE

CONTROL CARTRIDGE

C7 PORT

PRESSURE OK?

> 200 PSI

SV8 STEM

CARTRIDGE

SHIFTING OK?

YES

SIDE BRUSH DOES NOT LOWER

(FLOW CHART)

YES NO

C5 PORT

PRESSURE OK?

300 PSI

YES

G6 PORT

PRESSURE OK?

> 200 PSI

REPAIR OR REPLACE

SV11 STEM

CARTRIDGE

YES

REPAIR OR REPLACE

SV8 STEM

CARTRIDGE

REPLACE

SV10 STEM

CARTRIDGE

HYDRAULICS

5-70 7400 MM428 (12--98)

SQUEEGEE LIFT

STRAINER

RV1

RV2

P3 DR1

P1P2

RV3

3 PSI

3.7 GPM

2500

PSI

2500

PSI SV01

SV02

SV06

SV04

SV05

SV07

SV03

PR1

300

PSI

S.BR.

OPT

SQUEEGEE LIFT CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

350 PSI

1.0 GPM WHILE MOVING

HYDRAULICS

5-71

7400 MM428 (12--98)

SV3 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

REPAIR OR REPLACE

PC1 PILOT

CHECK CARTRIDGE

TV1

ORIFICE

PLUGGED?

SV3 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV3

STEM CARTRIDGE

YES

LIFT

CYLINDER SEALS

OK?

SQUEEGEE DOES NOT LOWER

(FLOW CHART)

YES NO

PC1 PILOT

CHECK CARTRIDGE

SHIFTING OK?

NO YES

CLEAN OR

REPLACE

ORIFICE

NO YES

REPLACE

LIFT

CYLINDER

HYDRAULICS

5-72 7400 MM428 (12--98)

SV3 STEM

MAGNETIZED?

CHECK

ELECTRICAL SYSTEM

REPAIR OR REPLACE

PC1 PILOT

CHECK CARTRIDGE

TV1

ORIFICE

PLUGGED?

SV3 STEM

CARTRIDGE

SHIFTING OK?

REPAIR OR

REPLACE SV3

STEM CARTRIDGE

YES NO

LIFT

CYLINDER SEALS

OK?

SQUEEGEE DOES NOT RAISE

(FLOW CHART)

YES NO

PC1 PILOT

CHECK CARTRIDGE

SHIFTING OK?

NO YES

CLEAN OR

REPLACE

ORIFICE

NO YES

REPLACE

LIFT

CYLINDER

HYDRAULICS

5-73

7400 MM428 (12--98)

REPAIR OR

REPLACE

PLUMBING

LIFT

CYLINDER

SEALS OK?

PC1 PILOT CHECK

CARTRIDGE

SHIFTING & SEAT OK?

REPAIR OR

REPLACE PC1 PILOT

CHECK CARTRIDGE

REPLACE

LIFT

CYLINDER

SQUEEGEE DOES NOT STAY UP

(FLOW CHART)

YES NO

PLUMBING

OK?

NO YES

HYDRAULICS

5-74 7400 MM428 (12--98)

STEERING SYSTEM

STRAINER

PROPEL SYSTEM

RV7

1160

RV3

3 PSI

RV5

4000

PSI

RV6

PSI

2400

RPM

RV4

4000

PSI

S--15

3.7 GPM

PSI

STEERING CIRCUIT

(SCHEMATIC)

PRESSURE

RETURN

SUCTION

CASE DRAIN

PRESSURE READINGS BASED

ON 150 F

750 PSI (STATIONARY)

850 PSI (TURNING)

1500 PSI (HELD AT STOP ON STEERING WHEEL)

3.7 GPM

No. 7-623

July,1995

Eaton®

Medium Duty Piston Pump

Repair Information

Model 70142 / 70144, 20.3 cm3/r [1.24 in3/r] Displacement

and 70145, 23.6 cm3/r [1.44 in3/r] Displacement

Variable Displacement Piston Pump design code 01 02

with Valve Plate

Model 70142 / 70144 and 70145

Introduction

Table of Contents

Introduction....................................................................................................... 2

Identification...................................................................................................... 3

Required Tools .................................................................................................. 3

Exploded View Drawing ..................................................................................... 4 & 5

Parts List ........................................................................................................... 6 & 7

Disassembly and Inspection.............................................................................. 8

Reassembly ....................................................................................................... 9

Appendix A: ....................................................................................................... 10

Appendix B: ....................................................................................................... 11

Fault-Logic Trouble Shooting ............................................................................ 12 - 16

Start-up Procedure ............................................................................................ 17

Introduction

This manual provides service information for the Eaton Models 70142 / 70144 and 70145 Variable

Displacement Piston Pumps. Step by step instructions for the complete disassembly, inspection, and

reassembly of the pump are given. The following recommendations should be followed to insure successful

repairs.

Remove the pump from the application.

Cleanliness is extremely important.

Clean the port areas thoroughly before disconnecting the hydraulic lines.

Plug the pump ports and cover the open hydraulic lines immediately after they're disconnected.

Drain the oil and clean the exterior of the pump before making repairs.

Wash all metal parts in clean solvent.

Use compressed air to dry the parts. Do not wipe them dry with paper towels or cloth.

The compressed air should be filtered and moisture free.

Always use new seals when reassembling hydraulic pumps.

For replacement parts and ordering information refer to parts list 6-632.

Lubricate the new rubber seals with a petroleum jelly (vaseline) before installation.

Torque all bolts over gasketed joints, then repeat the torquing sequence to make-up for gasket

compression.

Verifying the accuracy of pump repairs on an authorized test stand is essential.

Model 70142 / 70144 and 70145

Identification and

Tools Required

Identification Numbers

Stamped on each unit.

A- Product Number Discription

70142 = Piston Pump (20.3 cm3/r [1.24 in3/r]) with Gerotor

70144 = Piston Pump (20.3 cm3/r [1.24 in3/r]) without Gerotor

70145 = Piston Pump (23.6 cm3/r [1.44 in3/r]) with or without Gerotor

78113 = Tandem Piston Pumps (20.3 cm3/r [1.24 in3/r]) no Gear Pump

78114 = Tandem Piston Pumps (20.3 cm3/r [1.24 in3/r]) with Gear Pump

78115 = Tandem Piston Pumps (23.6 cm3/r [1.44 in3/r]) no Gear Pump

78116 = Tandem Piston Pumps (23.6 cm3/r [1.44 in3/r]) with Gear Pump

ABC D

Single Pump - Product Number

7 0 1 4 2 - R A A - 0 1

Required Tools

7/16 in. Hex Key (Allen)

9/16 in. End Wrench

1 in. End Wrench

9/16 in. Socket

1/2 in. Socket

Internal Retaining Ring Pliers (straight .090 tip)

External Retaining Ring Pliers (straight .070 tip)

O-ring Pick

Torque Wrench (135.6 N.m [100 lbf.ft] capacity)

Hammer (soft face)

Light Petroleum Jelly

Seal Driver

Arbor Press

Testers Initials

Day of Month

(two digits)

Month (two digits)

Serial Number Code:

B 93 01 31 JB

Revision level

of parts list.

Last two digits

of year built.

( 93 for 1993 etc.)

Tandem Pumps - Product Number

7 8 1 1 3 - R A B - 0 1

ABCD

B- Rotation,

R = Righthand,

L = Lefthand

C- Sequential Letters

D- Design Code Number

3-1 3

Date Code and

Assembly Number Location

Shaft assembly for

rear pump of tandem.

Shaft assembly for

single pump

or front pump

of tandem.

50-1

51-1

910

14 15

15 16

24 25

Model 70142 / 70144 and 70145

Parts

Drawing - Figure 1-1

Right Side

Left Side

Model 70142 / 70144 and 70145

2-1 2-2

1919-1

19-1

(K4-4)

2-1 2-2

19-1

27A

27B

28A

49-1

49-2

49-3

49-4

49-5

49-1

49-2

49-3

49-4

49-5

34-1

(K2-1)

K2-2

K2-3

(K3-1)

(K3-2)

(K3-3)

(K4-1)

K4-2

K4-3

K1-1

(K2-2)

K2-3

K2-4

Groove

design code

Model 70142 / 70144 and 70145

Parts List

Item Qty. Description

1 1 Drive Shaft

2 1 Backplate Assembly

3 1 Housing Assembly

4 1 Rotating Kit Assembly

5 1 Camplate

6 1 Washer

+ 7 1 Retaining Ring

+ 8 2 Retaining Ring

9 1 Thrust Bearing

10 2 Bearing Race

+ 11 1 Shaft Seal, Drive

+ 12 1 Housing Gasket

13 2 Needle Bearing

+ 14 1 O-ring, 3.175 mm Dia. x 31.75 mm ID. [.125 in. Dia. x 1.25 in. ID.]

15 2 Washer

+ 16 1 Shaft Seal, Trunnion

17 4 Screw, Pan Head

18 2 Spring

19 2 Plug Assembly

+ 19-1 2 O-ring, 2.38 mm Dia. x 22.23 mm ID. [.0937 in. Dia. x .875 in. ID.]

20 1 Relief Valve for Port “C”

21 1 Relief Valve for Port “D”

22 1 Inner Race

23 1 Seal Cover

24 1 Trunnion Cover

25 1 Cover, O-ring

26 2 Dowel Pin

27 2 Cap Screws, 5/16-18, 50.8 mm [2 in.] Long

28 2 Cap Screws, 5/16-18, 63.5 mm [2.5 in.] Long

29 1 Key, Drive Shaft

30 1 Key, Camplate Trunnion

31 1 Cover Plate (In K3 kit)

+ 32 1 O-ring (In K1, K2, K3 & K4 kit)

33 2 Cap Screws, Cover Plate (In K3 kit)

34 1 Plug Assembly

+ 34-1 1 O-ring, 2.21 mm Dia. x 16.36 mm ID. [.087 in. Dia. x .644 in. ID.]

+ 35 1 Molded O-ring

36 1 Charge Pump Adaptor

37 1 Gerotor set and coupler sub-assembly

6.9 cm3/r [.42 in3/r] displacement, 6.35 mm [.25 in ] width

13.8 cm3/r [.84 in3/r] displacement, 12.7 mm [.5 in] width

37 1 9 tooth coupler (In K4 kit)

46 1 Mounting Bracket, Square shaped

46 1 Mounting Bracket, “V” shaped

48 1 Valve Plate

Model 70142 / 70144 and 70145

Parts List

Item Qty. Description

49 1 Dump Valve sub-assembly

+ 49-1 1 Retaining Ring

49-2 1 Separator Plug

49-3 1 Separator

+ 49-4 1 O-ring, 1.59 mm Dia. x 9.53 mm I.D. [.0625 in. Dia. x .375 in. I.D.]

+ 49-5 1 O-ring, 2.46 mm Dia. x 19.18 mm I.D. [.097 in. Dia. x .755 in. I.D.]

49 1 Plug Assembly

49-5 1 O-ring, 2.46 mm Dia. x 19.18 mm I.D. [.097 in. Dia. x .755 in. I.D.]

50 1 Plug Assembly

+ 50-1 1 O-ring, 1.98 mm Dia. x 11.89 mm ID. [.078 in. Dia. x .468 in. ID.]

51 1 Plug Assembly

+ 51-1 1 O-ring, 1.98 mm Dia. x 11.89 mm ID. [.078 in. Dia. x .468 in. ID.]

Mounting Kits

K1 1 Tandem Piston Pump Mounting Kit

K1-1 1 35T Coupler, 36.8 mm [1.45 in.] long

K1-2 1 O-ring, 1.59 mm Dia. x 101.6 mm ID. [.0625 in. Dia. x 4 in. ID.]

K1-3 2 Cap Screws

K1-4 2 Washer

K2 1 Gear Pump Mounting Kit

K2-1 1 O-ring, 1.59 mm Dia. x 82.55 mm ID. [.0625 in. Dia. x 3.25 in. ID.]

K2-2 2 Washer

K2-3 2 Cap Screws

K3 1 Cover Plate Kit

K3-1 1 O-ring, 1.59 mm Dia. x 82.55 mm ID. [.0625 in. Dia. x 3.25 in. ID.]

K3-2 1 Cover Plate

K3-3 2 Cap Screws

K4 1 Gear Pump Mounting Kit with Coupler

K4-1 1 9T Coupler

K4-2 1 O-ring, 1.59 mm Dia. x 101.6 mm ID. [.0625 in. Dia. x 4 in. ID.]

K4-3 2 Cap Screws

K4-4 2 Washer

Seal Repair Kit

70142-938 Seal Repair Kit for 70142, 70144 and 70145 piston pump.

Legend + Included in seal repair kit.

Model 70142 / 70144 and 70145

Disassembly

8Remove housing gasket from housing or backplate.

9To remove rotating kit assembly from housing, first

remove pump from vise holding the rotating kit assembly in

position. Lower pump so that the shaft end (flange end) is up.

Set the rear of housing onto table with housing flat and rotating

kit assembly at rest on table. Hole in table for protruding shaft

is required. Remove by lifting the housing and shaft from

rotating kit assembly.

Refer to Appendix B for disassembly and Inspection of rotating

kit.

10 Remove retaining ring from the front of housing. Press the

shaft, shaft seal or spacer, and washer from housing. Remove

retaining ring, thrust washer, thrust bearing, second thrust

washer, and second retaining ring from shaft.

11 To remove camplate from housing, remove the two screws

from both sides of housing (four total) retaining seal cover and

trunnion cover. Remove seal cover, shaft seal, washer, and

bearing from housing. Remove trunnion cover, o-ring cover, o-

ring, washer, inner race, and bearing from housing. Slide the

camplate over to one side and remove thru the back side of

housing.

Camplate Inspection:

• The finish on the piston shoe surfaces of the camplate

should show no signs of scoring.

Housing Inspection:

• Check the bearing (press fit) in front of housing. If

needles remain in cage, move freely, and setting at the

dimension shown in figure 1-4, removal not required.

1.78 mm

[.07 in.]

Numbered End Flange End of Housing

Figure 1-4

12 Discard the shaft seal, gaskets, and o-rings from all

assemblies. Replace with new seals upon reassembly.

Disassembly

The following instructions apply to a variable displacement

piston pump with or without a gerotor charge pump. A tandem

pump assembly should be separated into individual pumps

before disassembly.

1Position the pump into a protected jaw vise, clamping onto

the outer portion of the flange, with the input drive shaft down.

Remove the four cap screws retaining charge pump adapter or

backplate.

No gerotor charge pump skip to step 6.

2Lift the charge pump adapter assembly straight up off

backplate, shaft, and gerotor. Gerotor may stay in adapter or on

backplate.

3Remove o-ring from charge pump adapter.

4Remove outer gerotor ring from either the charge pump

adapter or the inner gerotor ring.

Refer to Appendix A for disassembly and inspection of charge

pump adapter assembly.

5Remove the inner gerotor ring and coupler assembly from

shaft.

6Lift backplate straight up off of shaft and housing. Remove

valve plate from backplate or from rotating kit assembly, still in

housing.

7From backplate remove dump valve assembly or plug

assembly, and relief valve assemblies. Note: Mark the relief

valve in relationship to the cavity it was removed, for

reassembly purposes.

Backplate Inspection:

• Check the bearing (press fit) in backplate. If needles

remain in cage, move freely, and setting is at the dimension

shown in figure 1-3, removal not required.

• Check roll pin in backplate. If tight and set to the

dimension shown in figure 1-3, removal not required.

2.79 mm

[.110 in.]

1.91 mm

[.075 in.]

Numbered End

Figure 1-3

Model 70142 / 70144 and 70145

Reassembly

1All parts should be cleaned and critical moving parts

lubricated before reassembly.

2If necessary, press new bearing in housing to dimension

shown in figure 1-4 with the numbered end of bearing outward.

3Starting with the camplate, insert camplate into the housing

with the long trunnion side down and to the appropriate side of

linkage on the machine.

4 On the short trunnion side of camplate install bearing

(bearing with numbered side to the inside of pump), bearing

race (race with chamfer toward inside of pump), washer, o-ring,

o-ring cover, trunnion cover, and retain with two screws.

Torque screws 4.1 to 5.4 N.m [36 to 48 lbf.in].

5 On the long trunnion side of camplate install bearing

(bearing with numbered side to the inside of pump), washer,

trunnion shaft seal, seal cover, and retain with two screws.

Torque screws 4.1 to 5.4 N.m [36 to 48 lbf.in].

6To install shaft, place exterior retaining ring, thrust race,

thrust bearing, second thrust race, and second retaining ring

onto shaft. Position washer and shaft seal or spacer onto shaft.

7Install shaft assembly into front of housing: For units with

spacer, retain with interior retaining ring and go on to step 8.

For units with shaft seal, seat seal into position with seal driver

and retain with interior retaining ring.

Refer to Appendix B for reassembly of rotating kit assembly.

8With flange end of housing up, position rotating kit

assembly onto shaft and into housing. Align the spline within

the piston block with shaft internal spline. Make sure piston

block is engaged fully to put piston shoes in contact with

camplate. Check all parts for proper position before proceeding.

9Clamp pump assembly in a protected jaw vise with the

open end of the housing up. Install gasket and two dowel pins

onto housing.

10 If necessary, press new bearing and roll pin in backplate to

dimension shown in figure 1-3. Bearing installed with the

numbered end outward. Roll pin installed with split oriented

away from bearing.

11 Install new o-ring on relief valves. Install relief valve in its

original cavity in backplate that it was removed. Torque 128 to

142 N.m [95 to 105 lbf.ft.]

12 Install new o-ring on dump valve or plug. Install dump

valve or plug into backplate. Torque dump valve or plug to 36.6

to 40.7 N.m [ 27 to 30 lbf.ft]

13 Apply a small amount of petroleum jelly to the steel side of

valve plate to hold in place for installation. Aligning the index

pin, place the valve plate in position onto the backplate, with

steel side against backplate.

14 Install backplate assembly onto housing assembly. Making

sure valve plate and gasket stay in place.

No gerotor charge pump, skip to step 17.

15 Install inner gerotor and coupler assembly. The coupler has

a "V" groove on one end and this end of coupler should enter

backplate first. Lubricate inner gerotor.

Refer to Appendix A for reassembly of Charge relief valve in

adapter plate.

16 Install o-ring and outer gerotor ring onto adapter plate.

Lubricate both o-ring and outer gerotor ring to hold in position

during assembly of adapter plate. Install adapter plate onto

backplate. Make sure o-ring and gerotor ring stay in place.

17 Retain backplate and adapter plate (when used) with four

cap screws, Torque 23 to 27 N.m [17 to 20 lbf.ft].

18 Install new o-rings on all plugs. Install plugs into housing.

Torque 9/16 in. - 18 plug 28 to 32 N.m [21 to 24 lbf.ft].

19 Refer to start-up procedures on page 17.

1010

Model 70142 and 70145

Appendix A - Charge Pump Adapter Assembly

36-4

36-3 36-1

36-2

Gerotor Ring

Pocket

(See chart for

depth)

Bearing

36-4a

36-3a or 3b

36-2a

Configuration for

6.9 to 1.3 bar

[100 to 150 lbf/in

]

Charge Relief Valve

Charge Pump

Suction Port

Pressure Check Port or

Remote Charge Port

Configuration for

13.8 to 17.2 bar [200 to 250 lbf/in

] or

17.2 to 20.7 bar [250 to 300 lbf/in

]

Charge Relief Valve

Reassembly - Charge Pump Adapter Assembly

1If necessary, press new bearing in adapter assembly. The

bearing to dimension shown in figure 1-2 with the numbered

end of bearing outward and closest to mounting flange.

2Install cup poppet or pin poppet, spring, and spring

retainer into charge pump adapter. Torque retainer 6.8 to 9.5

N.m [5 to 7 lbf.ft.]

Numbered End

Gerotor Pocket

2.41 mm

[.095 in.]

Flange

Figure 1-2

Disassembly - Charge Pump Adapter Assembly

1Remove spring retainer, spring, and poppet from adapter

assembly.

Inspection:

• Inspect the charge pump relief valve seat inside the

charge pump adapter. Check to insure that seat is smooth and

free of burrs or other defects.

• Inspect the charge pump relief valve spring.

• Inspect the bearing inside the charge pump adapter.

The bearing needles must remain in the bearing cage and

bearing at dimension shown in figure 1-2.

• Inspect the gerotor pocket inside the charge pump

adapter assembly. It should not be scored excessively.

Item Qty. Description

36 1 Charge Pump Adapter Assy.

36-11 Bearing (press fit)

36-21 Poppet, Cup

36-2a 1 Poppet, Pin

36-31 Spring, Tappered

36-3a 1 Spring, "Light Green" *

36-3b 1 Spring, "Pink" **

36-41 Spring Retainer

36-4a 1 Spring Retainer

*200 to 250 lbf/in2

**250 to 300 lbf/in2

Gerotor Pocket Depth

Displacement Depth of Pocket

cm3/r [in3/r] mm [in.]

6.9 [.42] 6.35 [.25]

13.8 [.84] 12.7 [.50]

1111

Model 70142 / 70144 and 70145

Appendix B -

Rotating Kit Assembly

4-1

4-2 4-3

4-5

4-4

4-6 4-7 4-8

4-9

4-7

Item Qty. Description

4-19 Piston assemblies

4-21 Spider

4-31 Spider Pivot

4-41 Retainer

4-51 Piston Block

4-63 Pins

4-72 Washer

4-81 Spring

4-91 Retaining Ring

Disassembly - Rotating Kit Assembly

Disassembly of rotating assembly is required for inspection

only.

1Remove the nine piston assemblies, spider, and spider

pivot from piston block.

Inspection:

• Examine the O.D. of the pistons for finish condition.

They should not show wear or deep scratches. Inspect the

shoes for a snug fit on the ball end of the pistons and a flat

smooth surface that comes in contact with the camplate. Do not

lap piston shoes.

• Examine the spider for wear in the pivot area.

• Examine the pivot to insure smoothness and no signs

of wear.

• Inspect the piston block surface that makes contact

with valve plate. This surface should be smooth and free of

deep scratches. Do not lap piston block.

• The pistons should move freely in the piston block

bore. If not free moving, examine the bore for scoring or

contamination.

2To inspect pins and spring Caution should be taken in

removing spring. The spring is highly compressed and the

retaining ring should not be removed without compressing the

spring safely.

The following parts are required to disassemble the piston

block:2 ea. 5/16 in. I.D. x 15/16 in. O.D. flat washers

1 ea. 5/16 in. x 2-7/8 in. N.C. cap screw, and

1 ea. 5/16 in. N.C. nut

To remove spring, place one of the flat washers over the 5/16

in. x 2-7/8 in. cap screw. Put cap screw through the center of

the piston block and apply the second washer. Let washer rest

on the three pins and retain with nut. Turning nut and

compressing spring inside the block. Use a pair of retaining ring

pliers and remove the internal retaining ring. Remove nut, bolt,

and the two washers from block. Removing the washer, spring,

second washer, three pins, and pin keeper at the same time.

Reassembly - Rotating Kit Assembly

1To reassemble the rotating kit assembly complete the

following: Compress the pin keeper and install in the spline of

the piston block. Install the three pins with head end to the

inside of the block and position in the special grooves of the

piston block spline.

2Install the washer, spring, and second washer into the

piston block. Use the two 5/16 in. I.D. washers, nut, and 5/16

in. x 2-7/8 in. cap screw to compress the spring and retain with

retaining ring. Remove the nut, cap screw, and the two

washers.

3Install the pivot onto the three pins, spider on the pivot,

and piston assemblies thru the spider and into piston block,

resting on spider.

1212

Inspect

Repair

Replace

Defective

Action

Step

Comment

Number

Decision

Solution

Symptom:

Gauges Recommended

Inlet vacuum gauge: 207 bar to 0 bar [30 lbf/in2 to 30 inHg]

System pressure gauge: 700 bar [10,000 lbf/in2]

Charge pressure gauge: 0 to 50 bar [0 to 600 lbf/in2]

Case pressure gauge: 0 to 25 bar [0 to 300 lbf/in2]

Explanatory

Diagram

Model 70142 / 70144 and 70145

Fault - Logic

Trouble Shooting

This fault - logic trouble shooting guide is a diagnostic aid in

locating transmission problems.

Match the transmission symptoms with the problem statements

and follow the action steps shown in the box diagrams. This will

give expedient aid in correcting minor problems eliminating

unnecessary machine down time.

Following the fault - logic diagrams are diagram action

comments of the action steps shown in the diagrams. Where

applicable, the comment number of the statement appears in

the action block of the diagrams.

Recommended Gauge Locations

Figure 3-1

Pressure Ports

Tee in line to check System

Pressure

Charge Pump Suction Port

Tee in line to check Inlet Vacuum

Drain Port

Tee in line to check Case

Pressure

Auxiliary Port

Check Charge Pressure

1313

Model 70142 / 70144 and 70145

Fault - Logic

Trouble Shooting

Inspect

Servo Control

(If used)

Inspect

External Control

Linkage

Defective

Repair

Replace

Defective

Repair

Replace

Symptom: Neutral Difficult or Impossible to Find

Inspect

Heat

Exchanger OKOK OK

456

Check

Oil Level in

Reservoir

Fill to

Proper

Level

DefectiveBelow Level

Repair

Replace

Check

System

Pressure

Reduce

System

Load

High

OK 9

Inspect

Charge Relief

Valve

OK 11

Inspect

Charge

Pump 13

Inspect

Motor 12

Inspect

Inlet Screen

or Filter

Replace

Clogged

OK 8

Check

Charge

Pressure

Low OK

Replace

Pump &

Motor

Inspect

Dump Valve

(If used)

OK 7

Inspect Heat

Exchanger

By-Pass Valve

(If used)

Defective

Repair

Replace

Defective

Repair

Replace

Defective

Repair

Replace

Defective

Repair

Replace

Defective

Repair

Replace

Symptom: System Operating Hot

1414

Model 70142 / 70144 and 70145

Fault - Logic

Trouble Shooting

Inspect

Servo Control

(If used)

OK OK

123

Inspect

External Control

Linkage

Defective

Repair

Replace

Inspect

System Relief

Valves

Defective

Repair

Replace

Defective

Repair

Replace

Symptom: Operates in One Diection Only

Inspect

Servo Control

(If used) OKOK OK

Defective

Repair

Replace

Inspect

Motor

Replace

Clogged

Check

Charge

Pressure

Low OK

Inspect

Dump Valve

(If used)

Replace

Pump &

Motor

Defective

Repair

Replace

Inspect

Inlet Screen

or Filter OK

OK OK

813

Defective

Repair

Replace

Inspect

Charge Relief

Valve

Inspect

Charge

Pump

Defective

Repair

Replace

Defective

Repair

Replace

Symptom: System Response Sluggish

1515

Model 70142 / 70144 and 70145

Fault - Logic

Trouble Shooting

Check External

Control

Linkage OKOK OK

417

Check

Oil Level in

Reservoir

Fill to

Proper

Level

DefectiveBelow Level

Repair

Replace

Check

System

Pressure

OK 9

Inspect

Charge Relief

Valve

OK 11

Inspect

Charge

Pump 13

Inspect

Motor 12

Inspect

Inlet Screen

or Filter

Replace

Clogged

OK 8

Check

Charge

Pressure

Low OK

Replace

Pump &

Motor

Inspect

Servo Control

(If used)

OK 2

Inspect

Dump Valve

(If used)

Defective

Repair

Replace

Defective

Repair

Replace

Defective

Repair

Replace

Defective

Repair

Replace

Defective

Repair

Replace

High

Reduce

System

Load

Symptom: System Will Not Operate In Either Direction

1616

11 Inspect Charge Relief Valve for:

a. improper charge relief pressure setting *

b. damaged or broken spring

c. poppet valve held off seat

12 Inspect Motor for:

a. disconnected coupling

13 Inspect Charge Pump for:

a. broken or missing drive key

b. damaged or missing o-ring

c. excessive gerotor clearance

d. galled or broken gerotor set

* System/Charge Relief Valve

Pressure Settings for

Eaton’s Variable Displacement

Controlled Piston Pumps

Inlet Vacuum 6 inHg max.

Case Pressure 25 lbf/in2 maximum

Charge Pressure 100 to 150 lbf/in2 Standard

200 to 250 lbf/in2 Optional

250 to 300 lbf/in2 Optional

System Pressure 5000 lbf/in2 maximum

3000 lbf/in2 continuous

The high pressure relief valves are all factory preset and cannot

be readjusted.

The pressure setting and assembly number is stamped on each

high pressure relief valve cartridge.

Valve Identification Example:

32060-IA 5000

Relief Valve Setting

Relief Valve Assembly Number

Model 70142 / 70144 and 70145

Fault - Logic

Trouble Shooting

Diagram Action Step Comments

1Inspect External Control Linkage for:

a. misadjusted or disconnected

b. binding, bent, or broken

c. misadjusted, damaged or broken neutral return spring

2Inspect Servo Control Valve for: (if used)

a. proper inlet pressure

b. misadjusted, damaged or broken neutral return spring

c. galled or stuck control spool

d. galled or stuck servo piston

3Inspect System Relief Valves * for:

a. improper pressure relief setting

b. damaged or broken spring

c. valve held off seat

d. damaged valve seat

4Check Oil Level in Reservoir:

a. consult owner/operators manual for the proper type

fluid and level

5Inspect Heat Exchanger for:

a. obstructed air flow (air cooled)

b. obstructed water flow (water cooled)

c. improper plumbing (inlet to outlet)

d. obstructed fluid flow

6Inspect Heat Exchanger By-Pass Valve for: (if used)

a. improper pressure adjustment

b. stuck or broken valve

7Inspect Dump Valve for: (if used)

a. held in a partial or full open position

8Inspect Inlet Screen or Filter for:

a. plugged or clogged screen or filter element

b. obstructed inlet or outlet

c. open inlet to charge pump

9Check System Pressure:

a. See figure 3-1 for location of pressure gauge

installation.

b. consult owner/operators manual for maximum system

relief valve settings

10 Check Charge Pressure:

a. See figure 3-1 for location of pressure gauge

installation.

b. consult owner/operators manual for maximum charge

relief valve settings

1717

Model 70142 / 70144 and 70145

Start-up Procedure

When initially starting a new or a rebuilt transmission system, it

is extremely important that the start-up procedure be followed.

It prevents the chance of damaging the unit which might occur

if the system was not properly purged of air before start-up.

1After the transmission components have been properly

installed, fill the pump housing at least half full with filtered

system oil. Connect all hydraulic lines and check to be sure they

are tight.

2Install and adjust all control linkage.

3Fill the reservoir with an approved oil that has been filtered

through a 10 micron filter. Refer to Eaton Hydraulics Technical

Data sheet number 3-401 titled Hydraulic Fluid

Recommendations.

4Gasoline or L.P. engines: remove the coil wire and turn the

engine over for 15 seconds. Diesel engines: shut off the fuel

flow to the injectors and turn the engine over for 15 seconds.

5Replace the coil wire or return the fuel flow to the injectors.

Place the transmission unit in the neutral position, start the

engine and run it at a low idle. The charge pump should

immediately pick up oil and fill the system. If there is no

indication of fill in 30 seconds, stop engine and determine the

cause.

6After the system starts to show signs of fill, slowly move

pump camplate to a slight cam angle. Continue to operate

system slowly with no load on motors until system responds

fully.

7Check fluid level in the reservoir and refill if necessary to

the proper level with an approved filtered oil.

8Check all line connections for leaks and tighten if

necessary.

9The machine is now ready to be put into operation.

10 Frequent filter changes are recommended for the first two

changes after placing the machine back into operation. Change

the first filter in 3-5 hours and the second at approximately 50

hours approx. hours. Routinely scheduled filter changes are

recommended for maximum life of the hydraulic system.

1818

Model 70142 / 70144 and 70145

Notes

1919

Model 70142 / 70144 and 70145

Notes

Form No. 7-623

November, 1993

Printed in USA

Eaton Corporation

15151 Hwy. 5

Eden Prairie, MN 55344

Telephone 612/937-9800

Fax 612/937-7130

Hydraulics Division Eaton Ltd.

Glenrothes, Fife

Scotland, KY7 4NW

Telephone 44/592-771-771

Fax 44/592-773-184

Hydraulics Division

Order parts from number 6-632 Parts Information booklet.

Each order must include the following information.

1. Product and/or Part Number

2. Serial Code Number

3. Part Name

4. Quantity

No. 7-118

May, 1999

Char-Lynn®

Disc Valve Motor

4000 Series

Geroler® Motors Std., Whl. and Brgl.-004 Std. and Whl.-006

Repair Information

4000 Series Char-Lynn Motors

Retainer,

Front

(Flange)

Retainer, Front

(C Flange)

Housing, Bearing

Screw,

Cap

Screw, Cap Screw, Cap

Valve Housing Inner

Face

Seal

Outer

Face

Seal

Spring

Piston Shuttle

Seal

Balance

Ring

Valve

Plate

Valve

Drive

Geroler

Drive

Seal

Geroler

Shaft

Face

Seal

Bearingless Motor

Mounting Flange

Bearing Housing

Wheel Motor Back-up

Washer

(if supplied)

O-ring

Poppet

Spring

Sleeve, Dash Pot

Shaft

Seal

Shuttle (Two Way)

Shuttle Valve

Location when

Applicable Dust

Seal

Dust

Seal Seal

Guard

Shaft and

Bearing Kit

(1-1/4 inch Straight)

Shaft and

Bearing Kit

(1-5/8 inch Tapered)

Shaft and Bearing Kit

(1-1/4 inch

14 Tooth Splined)

Plug

Assembly

Plug

Assembly

Plug Assembly

Check

Valve

Plug

Assembly

Ball Plug

Key

Nut

Key

Retainer

Spring

4000 Series Char-Lynn Motors

Tools required for disassembly and reassembly

— Torque wrench (68 Nm [600 lb-in] capacity)

— 300 to 400 mm [12 to 16 inch] breaker bar

— 3/4 inch and 1/2 inch sockets

— Small screwdriver (150 to 200 mm [6 to 8 inch] long,

6 mm [.25 inch] blade)

— 3/16 inch Hex Key

— Hydraulic press — 1335 N [300 lbf]

— Shaft face seal (-004) installation tool 600468

— Shaft face seal (-006) installation tool 600421-2

*— Bullet (600463) for 1-1/4 inch diameter shafts

— Shaft seal installation tool (2 -1/4 inch socket)

— Torq wrench required for eight mounting flange

screws (replacement screws or -006 design)

No. E10

The following tools are not necessary for disassembly

and reassembly but are extremely helpfull

— Alignment studs (2), see dimensions below

*Available by special order, contact Eaton Corp.,

Hydraulics Division Service Dept.

200 mm [8 inch]

Approx. 13 [.5]

6,3 [.25] Grind Flat Spots on Each Side

11 mm [7/16 inch] Dia. Steel Rod

25 mm

[1 inch]

7/16-20 UNF

Wheel motor and bearingless motor repair information on page 9 and 10.

Shuttle valve and seal guard repair information on page 10.

Seal guard reference on page 10.

Tools

4000 Series Char-Lynn Motors

Disassembly

Cleanliness is extremely important when repairing a hydraulic motor.

Work in a clean area. Before disconnecting the lines, clean port area of

motor thoroughly. Use a wire brush to remove foreign material and

debris from exterior joints of motor. Check shaft and keyway. Use

600 grit paper/cloth to remove all nicks, burrs, and sharp edges that

might damage the shaft seals when installing retainer on shaft and

bearing assembly. Before starting disassembly procedures, drain oil

from inside of motor.

1 Place motor in a vise with output shaft down. Clamp across edge

of mounting flange, not on housing (see Figure 1). Excessive

clamping pressure will cause distortion. When clamping, use some

protective device on vise, such as special soft jaws, pieces of hard

rubber or board.

Although not all drawings show the motor in a vise, it is recom-

mended that you keep the motor in the vise during disassembly.

Follow the clamping procedures explained throughout the manual.

2 Remove 4 bolts from the valve housing.

3 Lift valve housing straight up. If done carefully, the springs and

balance ring subassembly will remain on valve for easy removal.

4 Carefully remove the following from the valve housing:

1 seal, 82,3 mm [3.24 inch] I.D.

1 seal, 8,9 mm [.35 inch] I.D.

2 check valve plug assemblies (plug, seal, spring, ball) 1 plug (case

drain) with seal.

5 Remove 2 balance ring springs.

6 Remove balance ring subassembly.

7 Remove inner and outer face seals from the balance ring.

8 Lift off valve.

Figure 1

Figure 2

Plug

Assembly Valve

Housing

Check

Plug

Assembly Seal

Seal

Figure 3

Spring Balance Ring

Valve

Figure 4

Inner

Face

Seal Outer Face Seal

4000 Series Char-Lynn Motors

Disassembly

9 Remove valve plate.

10 Remove 88,6 mm [3.49 inch] I.D. seal from valve plate (see

Figure 5).

11 Remove valve drive (see Figure 5).

12 Remove Geroler. Retain rollers in outer Geroler ring if they are

loose.

13 Remove 2 seals from Geroler, 1 seal on each side of Geroler.

14 Remove drive.

15 Remove 88,6 mm [3.49 inch] I.D. seal from bearing housing.

17 Remove shaft seal, back-up ring (if used) and dust seal from flange.

Use a small screwdiver to remove dust seal. Do not damage bore of

flange.

16 Use a stud remover or vise grips to remove studs (earlier models

only). Clamp bearing housing in vise as shown in Figure 7. Loosen 8

screws. Remove screws, washers (discard washers, as they are not

required for reassembly), and mounting flange (see Figure 8).

Valve

Plate Seal Seal

Valve Drive

Figure 5

Figure 6

Seal Seal

Geroler Drive

Figure 7

Figure 8

Shaft

Seal Back-up

Ring

Mounting

Flange

Dust

Seal

Figure 9

4000 Series Char-Lynn Motors

Reassembly

Check all mating surfaces. Replace any parts that have scratches or

burrs that couId cause leakage. Clean all metal parts in clean solvent.

Blow dry with air. Do not wipe with cloth or paper towel because lint

or other matter could get into the hydraulic system and cause damage.

Do not use a coarse grit papers/cloth or try to file or grind motor parts.

Check around the keyway and chamfered area of the shaft for burrs,

nicks, or sharp edges that can damage the seals when reassembling

the retainer.

Note: Lubricate all seals (prior to installation) with petroleum jelly

such as Vaseline®. Use new seals when reassembling the motor.

21 Place bearing housing on smooth flat surface with largest open end

of housing up. Apply petroleum jelly to shaft face seal. Install seal in

seal seat. Seat seal properly in groove (see Figure 11). A damaged or

improperly installed shaft face seal could cause internal lubrication

loss and subsequent parts wear.

22 Install shaft and bearing assembly in bearing housing (see Figure

12). Do not damage seal in bore of housing. You may need a press to

install shaft and bearing assembly.

18 Remove shaft and bearing assembly. You may need a press to

remove shaft and bearing assembly (see Figure 10).

19 Remove shaft face seal from bore of bearing housing (see Figure

10). Do not damage bore of bearing housing.

Note: Individual parts of the shaft and bearing assembly are not sold

separately and must be replaced as a unit.

Disassembly

Bearing Housing

Shaft and

Bearing

Assembly

Seal

Shaft Face Seal

Figure 10

Figure 11

Seal

Driver Seal

Tube

Seal

Seat

Bearing

Housing

Seal

Face

Seal

Note: Shaft face seal installation tool is available by special order.

Contact Eaton Corporation, Hydraulics Division (Service Department).

600468 (-004) 600421-2 (-006).

Figure 13

Shaft

Face

Seal

Flange

Shaft and

Bearing

Assembly

Back-up Ring Dust Seal Lip

Shaft Seal

Figure 12

Bearing

Housing

Shaft and

Bearing

Assembly

4000 Series Char-Lynn Motors

27 Lubricate threads of 8 screws with a film of light oil. Install and

finger tighten screws. Clamp bearing housing in vise. Torque screws

to 6 Nm [50 lb-in] in sequence (see Figure 14). Then final torque to 34

Nm [300 lb-in], in sequence. Install key (when used) in keyway of

shaft.

Note: Full torque 34 Nm [300 lb-in] on one bolt at a time can

damage bolt or retainer.

29 Pour a small amount of light oil inside the output shaft.

30 Apply a light film of petroleum jelly on 88,6 mm [3.49 inch] I.D.

seal. Install seal in bearing housing.

31 Install drive in output shaft (insert longer splined end of drive first),

(see parts drawing on page 2).

32 To help in the reassembly procedure, it is recommended using two

alignment studs (see special tools page 3) diagonally opposed in the

four bolt holes of the bearing housing.

33 Apply petroleum jelly on 2 seals, 9,3 mm [.25 inch] I.D. Install seals

(1 on each side of Geroler) in case drain grooves of Geroler.

Note: Installation at this point involves 3 steps in timing the motor.

Timing determines the direction of rotation of the output shaft.

Timing parts include:

1. Geroler

2. Valve drive

3. Valve Plate

4. Valve

23 Apply petroleum jelly to 88,6 [3.49] ID seal. Install seal in seal

groove of bearing housing (see Figure 13).

24 Use a small press, if available, to install dust seal in retainer. Metal

side of dust seal must face toward flange, as shown in Figure 13. If a

press is not available, use a plastic or rubber hammer to tap dust seal

in place.

25 Install 92,1 [3.62] ID seal, back-up ring and shaft seal in retainer.

Flat or smooth side of shaft seal must face toward retainer as shown in

Figure 13. Apply petroleum jelly to inside diameter of shaft seal (after

installing seal).

26 Before installing retainer, place a protective sleeve of bullet (see

note below) over shaft. Grease inside diameter of dust and shaft seals.

To prevent damage to seals, install retainer over shaft with a twisting

motion. Do not cut or distort shaft seal. Damage to shaft seal will

cause external leakage.

Note: Bullet 600463 for 1-1/4 inch diameter shafts available by

special order through Eaton Hydraulics Division service department.

Figure 14

Figure 15

28 Reposition motor in vise with output shaft down. Clamp across

edges of retainer as shown in Fig. 15.

Rotate Valve Clockwise

1/2 Tooth to Engage Spline

Valve

Plate

Alignment

Ref. Only

Note: Case Drain Holes (2)

Proper Alignment Shown Case Drain

Hole

Do Not Use

as a drain

hole Pressure

Relief Hole

Anyone of 6 Ports

Open to Outside

of Valve

Largest Open

Pocket

Geroler

Figure 16 Timing Alignment

Timing Step No. 1 — Locate largest open pocket in Geroler. Then

mark location of pocket on outside edge of Geroler (see Figure 16).

34 Align case drain hole and pressure relief hole in Geroler with case

drain hole and pressure relief hole in bearing housing. Install Geroler

on bearing housing (see Figure 16). Retain rollers in outer Geroler ring

if they are loose.

35 Install valve drive in Geroler.

Reassembly

4000 Series Char-Lynn Motors

Reassembly

36 Apply a light film of petroleum jelly on 88,6 mm [3.49 inch] I.D.

seal. Install seal in valve plate.

37 Align case drain hole in valve plate with case drain hole in Geroler.

Install valve plate (seal side toward Geroler) on Geroler as shown in

Figure 16.

Timing Step No. 2 — Locate slot opening in valve plate which is in

line with largest open pocket of Geroler (see Figure 16).

38 Use the following procedure for installing the valve on the valve

plate.

Timing Step No. 3 — Locate any one of the side openings of the

valve that goes through to the face of the valve. Line up this side

opening in the valve with open slot of valve plate that is in line with

largest open pocket of Geroler. Rotate valve clockwise (1/2 spIine

tooth) to engage valve with the valve drive spline, alignment reference

shown in Figure 17 (above). This procedure provides standard timing

when pressurized as shown in Figure 17.

39 Apply clean grease on balance ring assembly springs. Install

springs in 2 holes located inside bore face of valve housing (see

Figure 18).

41 Apply a light film of petroleum jelly on 82,3 mm [3.24 inch] I.D.

seal. Install seal in outside seal groove of valve housing.

42 Apply petroleum jelly on inner and outer face seals. Install seals on

balance ring as shown in Figure 19.

Important: Install face seals in the positions shown in Figure 19 or

the motor will not operate properly. Do not force or bend these face

seals. Any damage to these seals will affect the operation of the

motor.

43 Align 2 pins of balance ring with 2 spring holes in valve housing as

shown in Figure 20 . Install balance ring in valve housing.

40 Apply a light film of petroleum jelly on 8,9 mm [.35 inch] I.D. seal.

Install seal in case drain groove of valve housing.

Figure 19

Balance Ring

Pin Inner Seal Outer Seal

Valve

Housing

Seal

Figure 18

Seal

Balance Ring

Spring

Clockwise

Rotation

Counter

Clockwise

Rotation

Figure 17

Figure 20

Figure 21

4000 Series Char-Lynn Motors

Wheel Motors

Reassembly 45 Install and finger tighten 2 bolts (or studs for earlier models)

opposite alignment studs. Remove alignment studs and install

remaining bolts (or studs and 4 nuts for earlier models). Torque bolts

(or nuts) to 85 Nm[750 lb-in], in sequence (see Figure 23).

46 Install 2 check plug assemblies (ball, spring, plug with seal). Also

install case drain plug with seal, parts shown in Figure 22 (plug torque

shown in Figure 24).

A different bearing housing is used on wheel

motors (see Figure 24). Other than this, the

parts are the same as the standard motor and

the same disassembly and reassembly

procedures apply.

Bearingless Motors

This motor is the same as the standard without the shaft/bearing

assembly, bearing housing and retainer. The mounting flange replaces

the bearing housing (see Figure 25). Follow same disassembly and

reassembly procedures as rear section of standard motor.

Important: Loctite® information for bearingless motor on page 10.

44 Insert your finger through port of housing. Apply pressure to side

of balance ring assembly. Hold ring in position until valve housing is

in place (see Figure 21). Align case drain hole in housing with case

drain hole in valve plate. Install valve housing against valve plate (see

Figure 22).

Note: After installing valve housing on valve plate, check between

body parts of motor for unseated seals.

Figure 22

Check Plug

Assembly

Bolt Plug Assembly

Key Seal

Shaft

Seal

Retainer

Dust

Seal

Nut

Cap ScrewBackup Ring

Figure 24

Figure 25

Drive Seal Seal

O-ring

Seal

Mounting

Flange

Figure 23

7/16-20 Drain

Plug Torque to

17 Nm [150 lb-in]

(lubricated threads)

Check Plug

Torque to

7-14 Nm

[60-120 lb-in]

(lubricated threads)

4000 Series Char-Lynn Motors

Important: This motor requires Loctite in threaded holes of

mounting flange.

Follow these procedures:

Adequate Loctite penetration and sealing depend highly on cleanliness

and dryness of threads. Use a non-petroleum base solvent to clean

excess oil from threads of flange after disassembly. You may need to

use a tap to clean threads of excess old Loctite. After you have fully

reassembled the motor, apply 2 to 3 drops of Loctite no. 290 at top of

threaded holes (see Figure 26).

Note: Allow Loctite 5 minutes for thread penetration before installing

motor on gear case.

Reassembly

Figure 26

Attention:

Do not use

more than

3 drops of

Loctite on

threaded

portion.

Motors with Shuttle

and, or Seal Guard

Piston

Poppet

Dash

Pot

Plug/O-ring

S/A (9/16-18)

Torque to

41 Nm [360 lb-in]

(Lubricated Thread)

Enlarged

Parts

Drawing

Plug/O-ring*

S/A (9/16-18)

Torque to

23 Nm [200 lb-in]

(Lubricated

Thread)

Plug/O-ring

S/A (3/8-24)

Torque to

5 Nm [50 lb-in]

(Lubricated

Thread)

*Plug/O-ring S/A must be removed and

drain line added for shuttle valve operation.

Plug/

O-ring

S/A

Optioal

Seal Guard

Dash

Pot

Spring

Poppet

4000 Series Char-Lynn Motors

Char-Lynn

Product number

Eaton Corp. Hydraulics Div.

Eden Prairie, MN 55344

Product Number

109 0000 000

110 0000 000

111 0000 000

Product Line

Identification

Number

Product

Identification

Number

Engineering

Change

Code

Week of

Year 01

Thru 52

Last

Number

of Year

Date Code

00 0

For more detailed information contact Eaton Corp. Hydraulics

Division 15151 Highway 5 Eden Prairie, MN 55344.

Specifications and performance data, Catalog No. 11-878.

Replacement part numbers and kit information — Parts

Information No. 6-126.

Each Order Must Include the Following:

How to Order Replacement Parts

1. Product Number

2. Date Code

3. Part Name

4. Part Number

5. Quantity of Parts

Product Numbers—4000 Series Motors

Use digit prefix —109-, 110-, or 111- plus four digit number from charts

for complete product number—Example 111-1057.

Orders will not be accepted without three digit prefix.

109-1100 -1101 -1102 -1103 -1104 -1105 -1106 -1212

1-1/4 inch Straight

Standard

SAE

B-Mount

Standard

SAE

C-Mount

Displ. cm

/r [ in

/r] Product Number

ShaftMounting 130

[ 7.9] 160

[ 9.9] 205

[12.5] 245

[15.0] 310

[19.0] 395

[24.0] 495

[30.0]

110

[ 6.7] 625

[38.0]

109-1114 -1115 -1116 -1117 -1118 -1119 -1120 —

Ports

1-5/8 Inch

Tapered 110-1081 -1082 -1083 -1084 -1085 -1086 -1087 1116

111-1033 -1034 -1035 -1036 -1037 -1038 -1039 -1062

1-1/16 O-ring

Bearingless

Wheel

Motor

1-1/4 Inch

14 T Splined

111-1057

1-1/16 O-ring

1-1/16 O-ring -1215

—

-1117

-1063

109-1184 -1185 -1227 -1224 -1225 -1189 -1190 —40 mm Straight G 3/4 (BSP) —

111-1052 -1053 -1054 -1055 -1056 -1057 -1058 —

G 3/4 (BSP) —

110-1074 -1075 -1076 -1077 -1078 -1079 -1080 —

1-1/4 inch Straight 1-1/16 O-ring -1122

110-1088 -1089 -1090 -1091 -1092 -1093 -1094 —

1-1/4 Inch

14 T Splined 1-1/16 O-ring —

109-1001 -1054 -1002 -1003 -1055 -1056 -1057 —

3/4 inch Split Flange —

109-1011 -1062 -1012 -1013 -1063 -1064 -1065 —

3/4 inch Split Flange —

110-1001 -1040 -1002 -1003 -1041 -1042 -1043 —

3/4 inch Split Flange —

110-1006 -1044 -1007 -1008 -1045 -1046 -1047 —

3/4 inch Split Flange —

110-1011 -1048 -1012 -1013 -1049 -1050 -1051 —

3/4 inch Split Flange —

111-1044 -1015 -1045 -1046 -1016 -1017 -1018 —

3/4 inch Split Flange —

1-5/8 Inch

Tapered

109-1107 -1108 -1109 -1110 -1111 -1112 -1113 —

1-1/16 O-ring —

109-1006 -1058 -1007 -1008 -1059 -1060 -1061 —

3/4 inch Split Flange —

109-1191 -1192 -1193 -1194 -1195 -1196 -1197 —

1-1/2 Inch

17 T Splined G 3/4 (BSP) —

110-1108 -1109 -1110 -1111 -1112 -1113 -1125 —

40 mm Straight G 3/4 (BSP) —

Printed in USA

Form No. 7-118

Disc Valve Motors

4000 Series Motors

Sumitomo Eaton

Hydraulic Company Ltd.

Ooi-Cho Kameoka-Shi

621-0017 Kyoto

Japan

Telephone: [+81] 771-22-9601

Fax: [+81] 771-29-2020

Eaton Corporation

Hydraulics Division

15151 Hwy. 5

Eden Prairie, MN 55344

Telephone: 612/937-7254

Fax: 612/937-7130

Eaton Ltd.

7th Floor, Woo Duk Building

832-2 Yeoksam-Dong, Kangnam-Ku

Soeul 135-750

Korea

Telephone: [+82] 2-557-0595

Fax: [+82] 2-557-1634

Eaton Ltd.

Hydraulics Division

Glenrothes, Fife

Scotland, KY7 4NW

Telephone: [+44] (0)1592-771-771

Fax: [+44] (0)1592-773-184

Eaton Hydraulics (Shanghai) Co. Ltd.

388 Aidu Road, Waigaogiao FTZ

Pudong New Area

Shanghai 200137

Peoples Republic of China

Telephone: [+86] 21-5046 0758

Fax: [+86] 21-5046 0767

Eaton B.V.

Boeing Avenue 11

1119 PC Schiphol-Rijk

The Netherlands

Telephone: [+31] (0)20-655 6776

Fax: [+31] (0)20-655 6800

Jining Eaton Hydraulic Co. Ltd.

6 Ji Da Road

Jining City

Shandong Province 272131

Peoples Republic of China

Telephone: [+86] 537-2221288

Fax: [+86] 537-2221557

Sumitomo Eaton Hydraulic Co.

8 Temasek Blvd.

42-01 Suntec Tower Three

Singapore 03988

Telephone: [+65] 832-7727

Fax: [+65] 832-7733

www.eatonhydraulics.com

ISO-9001 CERTIFICATED FIRM

DET NORSKE VERITAS INDUSTRY BV, THE NETHERLANDS

ACCREDITED BY

THE DUTCH COUNCIL

FOR CERTIFICATION

Reg. No. 24

Qualitiy System Certified

Products in this catalog are manufactured

in an ISO-9001-certified site.

No. 7-310

January, 1995

Char-Lynn®

Power Steering

2 Series

Steering Control Unit 001

Repair Information

Dust

Seal

Housing Quad

Seal

Thrust

Bearing

Sleeve

Spool

Centerin

Springs

Bearing Race (2)

O-ring

Seal

O-ring

Seal

Wear

Plate

Drive

Gerotor

Spacer

Manual Steering

Relief Valve

O-ring

O-ring Seal

Ring

End

Cap

Screw

(7)

Plug

Check

Ball

Spring

Retaining

Ring

Power Steering

2 Series

Steering Control Units

Tools Required

• 10 mm Socket

• 7/8 in. Socket

• Torque Wrench (18 Nm [160 lb-in] Capacity)

• Small Blade Screwdriver

Power Steering

2 Series

Steering Control Units

Disassembly

Cleanliness is extremely important when repairing hydraulic

Steering Control Units (SCU). Work in a clean area. Before

disconnecting the hydraulic lines, clean the port area of the

SCU. Before disassembly, drain the oil, then plug the ports and

thoroughly clean the exterior of the SCU. During repairs,

always protect machined surfaces.

1 Remove the seven cap screws and disassemble the SCU as

shown in Figure 1.

2 Remove the plug and manual steering check as shown in

Figure 1.

Note: The manual steering check may be a check ball or a

check/relief valve.

3 Slide the spool and sleeve from the housing (see Figure 2).

4 Remove the thrust bearing and bearing races.

5 Remove the quad seal.

6 Using a small blade screwdriver, carefully pry the dust seal

from the housing.

Important: Do not damage the dust seal seat.

O-ring

Seal

O-ring

Seal

Wear

Plate Drive

Gerotor

Seal

Ring

Spacer

Manual Steering

Check/Relief Valve

O-ring

O-ring O-ring

End

Cap

Screw

(7)

Figure 1

Plug

Dust

Seal

Housing Quad

Seal

Thrust

Bearing

Bearing Race (2)

Spool and Sleeve

Figure 2

Power Steering

2 Series

Steering Control Units

7 Remove the pin that holds the spool and sleeve together

(see Figure 3).

8 Carefully slide the spool out of the sleeve. The springs

and retaining ring will stay with the spool as it's removed.

Reassembly

Check all mating surfaces. Replace any parts with

scratches or burrs that could cause leakage. Wash all

metal parts in clean solvent. Blow them dry with pressur-

ized air. Do not wipe parts dry with paper towels or cloth

as lint in a hydraulic system will cause damage.

Note: Always use new seals when reassembling

hydraulic steering control units. Refer to parts list 6-323

for seal kit part numbers, replacement parts, and

ordering information.

Important: During reassembly lubricate the new seals

with a petroleum jelly such as Vaseline®. Also lubricate

machined surfaces and bearings with clean hydraulic

fluid.

9 Remove the retaining ring and springs.

Caution: The centering springs are under tension. Remove

the retaining ring carefully.

10 Install the quad seal:

• Put one of the bearing races and sleeve into

the housing.

• Together, the housing and bearing race create

a groove into which the quad seal will be

installed.

• Hold the bearing race tightly against the input

end of the housing by pushing on the gerotor

end of the sleeve.

• Fit the quad seal into its seat through the input

end of the housing. Be sure the seal is not

twisted.

• Remove the sleeve and bearing race.

Centering

Springs and

Spacers

Sleeve

Spool

Figure 3

Spring

Retaining

Ring

Power Steering

2 Series

Steering Control Units

20 Lubricate and install a new o-ring seal in the groove in

the housing.

21 Install the wear plate and align the holes in the wear

plate with threaded holes in the housing.

Note: The holes in the wear plate are symmetrical.

22 Install the drive, be sure the slot in the drive engages

the pin.

23 Lubricate and install a new o-ring seal in the groove in

the wear plate.

24 Install the gerotor and align the screw holes.

25 Lubricate and install a new o-ring seal in the groove in

the gerotor ring.

26 Lubricate and install a new o-ring and seal ring in the

groove in the gerotor star.

27 Install the spacer.

28 Install end cap and seven cap screws. Tighten cap screws,

in a crisscross pattern, to 16 -18 Nm [140 -160 lb-in].

29 Remove the SCU from the vise.

30 Install the relief valve/check or check ball and plug. Use

a new o-ring and tighten the plug to 17 Nm [150 lb-in].

Quad Seal

Figure 4

Dust Seal Thrust Bearing

and Race (2)

Figure 5

11 Lubricate and install the dust seal (see Figure 4 for

correct seal orientation).

12 Install the centering springs in the spool. It is best to

install the two flat pieces first. Next, install the curved

pieces, three at a time.

13 Fit the retaining ring over the centering springs.

14 Apply a light coating of clean hydraulic fluid to the

spool and slide it into the sleeve. Be sure the centering

springs fit into the notches in the sleeve.

15 Install the pin (see Figure 3).

16 Apply a light coating of petroleum jelly to the inner

edge of the dust and quad seals.

17 Put the thrust bearing and races into the housing. The

thrust bearing goes between the two races (see Figure 2).

18 Apply a light coating of clean hydraulic fluid to the

spool and sleeve assembly and slide it into the housing.

Important: Do not damage the dust or quad seals.

19 Clamp the housing in a vise as shown in Figure 5. Use

just enough clamping force to hold the housing securely.

System

Product Numbers 2 Series (Standard — 69 Bar [1000 PSI])

Product Numbers 2 Series (High Pressure — 103 Bar [1500 PSI])

Ports Relief Valve

Setting

Bar [PSI] 31 [1.9] 39 [2.4] 63 [3.8] 74 [4.5] 100 [6.1]51 [3.1]

Displacement cm

/r [in

/r] and Product Number

291-1001-001None 291-1002-001 291-1003-001 291-1004-001 291-1005-001 291-1006-001

291-1001-04140 [ 580] 291-1002-041 291-1003-041 291-1004-041 291-1005-041 291-1006-041

291-1001-05150 [ 725] 291-1002-051 291-1003-051 291-1004-051 291-1005-051 291-1006-051

291-1001-06163 [ 914] 291-1002-061 291-1003-061 291-1004-061 291-1005-061 291-1006-061

291-1001-07170 [1015] 291-1002-071 291-1003-071 291-1004-071 291-1005-071 291-1006-071

293-4001-001None 293-4002-001 293-4003-001 293-4004-001 293-4005-001 293-4006-001

293-4007-001None 293-4008-001 293-4009-001 293-4010-001 293-4011-001 293-4012-001

Open

Center

Non-

Load

Reaction

Power

Beyond

Non-

Load

Reaction

Dynamic

Signal

Load

Sensing

9/16 Inch

Plug-O (4)

9/16 Inch

Plug-O (5)

9/16 Inch

Plug-O (5)

9/16 -18

Inch

SAE (4)

9/16 -18

Inch

SAE (5)

9/16 -18

Inch

SAE (5)

None

40 [ 580]

50 [ 725]

63 [ 914]

70 [1015]

None

40 [ 580]

50 [ 725]

63 [ 914]

70 [1015]

None

40 [ 580]

50 [ 725]

63 [ 914]

70 [1015]

291-1007-001 291-1008-001 291-1009-001 291-1010-001 291-1011-001 291-1012-001

291-1007-041 291-1008-041 291-1009-041 291-1010-041 291-1011-041 291-1012-041

291-1007-051 291-1008-051 291-1009-051 291-1010-051 291-1011-051 291-1012-051

291-1007-061 291-1008-061 291-1009-061 291-1010-061 291-1011-061 291-1012-061

291-1007-071 291-1008-071 291-1009-071 291-1010-071 291-1011-071 291-1012-071

291-5001-001 291-5002-001 291-5003-001 291-5004-001 291-5005-001 291-5006-001

291-5001-041 291-5002-041 291-5003-041 291-5004-041 291-5005-041 291-5006-041

291-5001-051 291-5002-051 291-5003-051 291-5004-051 291-5005-051 291-5006-051

291-5001-061 291-5002-061 291-5003-061 291-5004-061 291-5005-061 291-5006-061

291-5001-071 291-5002-071 291-5003-071 291-5004-071 291-5005-071 291-5006-071

291-5007-001 291-5008-001 291-5009-001 291-5010-001 291-5011-001 291-5012-001

291-5007-041 291-5008-041 291-5009-041 291-5010-041 291-5011-041 291-5012-041

291-5007-051 291-5008-051 291-5009-051 291-5010-051 291-5011-051 291-5012-051

291-5007-061 291-5008-061 291-5009-061 291-5010-061 291-5011-061 291-5012-061

291-5007-071 291-5008-071 291-5009-071 291-5010-071 291-5011-071 291-5012-071

291-1001-121None 291-1002-121 291-1003-121 291-1004-121 291-1005-121 291-1006-121

291-1001-081 80 [1160] 291-1002-081 291-1003-081 291-1004-081 291-1005-081 291-1006-081

291-1001-091 90 [1305] 291-1002-091 291-1003-091 291-1004-091 291-1005-091 291-1006-091

291-1001-101100 [1450] 291-1002-101 291-1003-101 291-1004-101 291-1005-101 291-1006-101

293-4001-121None 293-4002-121 293-4003-121 293-4004-121 293-4005-121 293-4006-121

293-4007-121None 293-4008-121 293-4009-121 293-4010-121 293-4011-121 293-4012-121

Open

Center

Non-

Load

Reaction

Power

Beyond

Non-

Load

Reaction

Dynamic

Signal

Load

Sensing

9/16 Inch

Plug-O

(4)

9/16 Inch

Plug-O

(5)

9/16 Inch

Plug-O (5)

9/16 -18

Inch

SAE

(4)

9/16 -18

Inch

SAE

(5)

9/16 -18

Inch

SAE (5)

None

80 [1160]

90 [1305]

100 [1450]

None

80 [1160]

90 [1305]

100 [1450]

None

80 [1160]

90 [1305]

100 [1450]

291-1007-121 291-1008-121 291-1009-121 291-1010-121 291-1011-121 291-1012-121

291-1007-081 291-1008-081 291-1009-081 291-1010-081 291-1011-081 291-1012-081

291-1007-091 291-1008-091 291-1009-091 291-1010-091 291-1011-091 291-1012-091

291-1007-101 291-1008-101 291-1009-101 291-1010-101 291-1011-101 291-1012-101

291-5001-121 291-5002-121 291-5003-121 291-5004-121 291-5005-121 291-5006-121

291-5001-081 291-5002-081 291-5003-081 291-5004-081 291-5005-081 291-5006-081

291-5001-091 291-5002-091 291-5003-091 291-5004-091 291-5005-091 291-5006-091

291-5001-101 291-5002-101 291-5003-101 291-5004-101 291-5005-101 291-5006-101

291-5007-121 291-5008-121 291-5009-121 291-5010-121 291-5011-121 291-5012-121

291-5007-081 291-5008-081 291-5009-081 291-5010-081 291-5011-081 291-5012-081

291-5007-091 291-5008-091 291-5009-091 291-5010-091 291-5011-091 291-5012-091

291-5007-101 291-5008-101 291-5009-101 291-5010-101 291-5011-101 291-5012-101

Power Steering

2 Series Steering Control Units

Power Steering

2 Series

Steering Control Units

Printed in USA

Form No. 7-310

Char-Lynn

Eaton Corp. Hydraulics Div.Hydraulics Div.

Eden Prairie, MN 55344

Product number

000 0000 000

000

Product Number

000 0000 000

Product Line

Identification

Number

Product

Identification

Number

Engineering

Change

Code

Week of

Year

01 Thru 52

Last Number(s)

of Year

Date Code

00 00

Relief Valve Pressure Code

00 = None

04 = 40 Bar [ 580 PSI]

05 = 50 Bar [ 725 PSI]

06 = 63 Bar [ 914 PSI]

07 = 70 Bar [1015 PSI]

08 = 80 Bar [1160 PSI]

09 = 90 Bar [1305 PSI]

10 = 100 Bar [1450 PSI]

Each Order Must Include the Following:

How to Order Replacement Parts

1. Product Number

2. Date Code

3. Part Name

4. Part Number

5. Quantity of Parts

For More Detailed Information Contact Eaton Corp. Hydraulics

Division 15151 Highway 5 Eden Prairie, MN 55344.

Specifications and performance data, Catalog No. 11-872

Replacement part numbers and kit information — Parts

Information No. 7-310.

Power Steering

2 Series

Steering Control Units

Eaton Corporation

Hydraulics Division

15151 Hwy. 5

Eden Prairie, MN 55344

Telephone 612/937-9800

Fax 612/937-7130

Eaton Ltd.

Hydraulics Division

Glenrothes, Fife

Scotland, KY7 4NW

Telephone 01-592-771-771

Fax 01-592-773-184

Eaton GmbH

Hydraulics Products

Am Schimmersfeld 7

40880 Ratingen, Germany

Telephone 02102-406-830

Fax 02102-406-800

ISO-9001 CERTIFICATED FIRM

DET NORSKE VERITAS INDUSTRY BV, THE NETHERLANDS

ACCREDITED BY

THE DUTCH COUNCIL

FOR CERTIFICATION

Reg. No. 24

Quality System Certified

Products in this catalog are manufactured

in an ISO-9001-certified site.

ENGINE--GAS/LP

6-1

7400 MM428 (3--02)

CONTENTS

Page

INTRODUCTION 6-3......................

LUBRICATION 6-4.....................

ENGINE OIL 6-4....................

COOLING SYSTEM 6-4................

ENGINE FAN BELT 6-5..............

AIR INTAKE SYSTEM 6-5..............

AIR FILTER INDICATOR 6-5.........

AIR FILTER 6-5.....................

TO REPLACE AIR FILTER

ELEMENT 6-6...................

FUEL SYSTEM -- GASOLINE 6-7........

FUEL FILTER 6-7...................

CARBURETOR 6-7.................

FUEL SYSTEM -- LPG 6-8..............

LP FUEL TANKS 6-10...............

TO CHANGE AN LPG FUEL

TANK 6-12......................

FUEL FILTER LOCK 6-14............

VAPORIZER-REGULATOR 6-14......

CARBURETOR 6-14................

OIL PRESSURE SWITCH 6-14.......

LPG FUEL TROUBLESHOOTING 6-15

CYLINDER HEAD 6-15.................

VALVE TAPPET CLEARANCE 6-15...

CRANKCASE VENTILATION

SYSTEM 6-15...................

GOVERNOR

TROUBLESHOOTING 6-16.......

GOVERNOR 6-24.....................

TO ADJUST GOVERNOR 6-24.......

DIGITAL CONTROLLER SET--UP 6-25

IGNITION SYSTEM 6-26...............

SPARK PLUGS 6-26................

TO REPLACE SPARK PLUGS 6-26...

FORD DISTRIBUTORLESS IGNITION

SYSTEM 6-27......................

SYNOPSIS 6-27....................

ENGINE TEMPERATURE 6-27.......

RUN MODE 6-28...................

SERVICING AND TESTING 6-28.....

“FAILURE MODE OF DIS”

IGNITION HARNESS 6-29........

FORD DIS IGNITION 6-30...........

ENGINE COOLANT SENSOR 6-31......

TO REPLACE ENGINE

ALTERNATOR 6-32.................

TO REPLACE ENGINE STARTER 6-34...

TO REMOVE ENGINE 6-35.............

TO INSTALL ENGINE 6-38..............

TO PURGE AIR FROM RADIATOR 6-40..

GAS ENGINE SERVICE MANUAL

FORD VSG--411/413

TENNANT Part Number 38978

ENGINE--GAS/LP

6-2 7400 MM428 (12--98)

ENGINE--GAS/LP

6-3

7400 MM428 (12--98)

INTRODUCTION

This section includes repair information on the

engine and related systems, such as fuel,

electrical, and drive belts.

ENGINE--GAS/LP

6-4 7400 MM428 (12--98)

LUBRICATION

ENGINE OIL

Check the engine oil level daily. Change the

engine oil and oil filter every 100 hours of machine

operation. Use 10W30 SAE--SG/SH rated engine

oil.

Fill the engine with oil to the level indicated on the

oil dipstick. The engine oil capacity is 3.3 L

(3.5 qt) including the oil filter.

COOLING SYSTEM

Check the radiator coolant level every 100 hours

of operation. Use clean water mixed with a

permanent-type, ethylene glycol antifreeze to a

-- 3 4 _C(--30_F) rating.

FOR SAFETY: When Servicing Machine,

Avoid Contact With Hot Engine Coolant.

ATTENTION! Never pour cold water or

cold antifreeze into the radiator of an

overheated engine. Allow the engine to

cool down to avoid cracking the

cylinder head or block. Keep the engine

running while adding water.

Check the radiator hoses and clamps every 200

hours of operation. Tighten the clamps if they are

loose. Replace the hoses and clamps if the hoses

are cracked, harden, or swollen.

Check the radiator core exterior and hydraulic

cooler fins for debris every 100 hours of

operation. Blow or rinse all dust, which may have

collected on the radiator, in through the grille and

radiator fins, opposite the direction of normal air

flow. The grille and hydraulic cooler open for

easier cleaning. Be careful not to bend the cooling

fins when cleaning. Clean thoroughly to prevent

the fins becoming encrusted with dust. Clean the

radiator and cooler only after the radiator has

cooled to avoid cracking.

FOR SAFETY: When Servicing Machine,

Wear Eye And Ear Protection When

Using Pressurized Air Or Water.

Flush the radiator and the cooling system every

800 hours of operation, using a dependable

cleaning compound.

ENGINE--GAS/LP

6-5

7400 MM428 (12--98)

ENGINE FAN BELT

The engine fan belt is driven by the engine

crankshaft pulley and drives the alternator pulley.

Proper belt tension is 13 mm (0.50 in) from a

forceof4to5kg(8to10lb)appliedatthe

mid-point of the longest span.

Check and adjust the belt tension every 100 hours

of operation.

AIR INTAKE SYSTEM

AIR FILTER INDICATOR

The air filter indicator shows when to clean or

replace the air filter element. Check the indicator

daily. The indicator’s red line will move as the air

filter element fills with dirt. Do not clean or replace

the air filter element until the red line reaches 5

kPa (20 in H2O) and the ”SERVICE WHEN RED”

window is filled with red. The indicator’s red line

may return to a lower reading on the scale when

the engine shuts off. The red line will return to a

correct reading after the engine runs for a while.

Reset the air filter indicator by pushing the reset

button on the end of the indicator after cleaning or

replacing the air filter element.

AIR FILTER

The engine air filter housing has a dust cap and a

dry cartridge-type air filter element. Empty the

dust cap daily. The air filter must be replaced

whenever the filter element is damaged or has

been cleaned three times.

Service the air filter element only when the air

filter indicator shows restriction in the air intake

system. Do not remove the air filter element from

the housing unless it is restricting air flow.

ENGINE--GAS/LP

6-6 7400 MM428 (12--98)

TO REPLACE AIR FILTER ELEMENT

FOR SAFETY: Before Leaving Or

Servicing Machine: Stop On Level

Surface, Set The Parking Brake, Turn Off

Machine And Remove Key.

1. Open the engine cover and side door.

2. Unscrew the clamp ring on the filter.

3. Remove the dust cap.

4. Empty the dust cap.

5. Remove the filter wing nut.

6. Pull the filter element out of the filter

housing.

7. Clean the interior of the air cleaner housing

with a camp cloth. Clean the element

housing sealing surfaces.

8. Using an air hose, direct dry, clean air

maximum 205 kPa (30 psi) up and down

pleats on the inside of the filter. Do not rap,

tap, or pound dust out of the element.

FOR SAFETY: When Servicing Machine,

Wear Eye And Ear Protection When

Using Pressurized Air Or Water.

9. After cleaning the air filter element, inspect it

for damage by placing a bright light inside.

The slightest rupture requires replacement

of the filter. Clean and inspect the seals on

the ends of the element. They should be

unbroken and flexible. Remember to replace

the element after cleaning it three times.

10. Install the new or cleaned filter element so

the fins on the element are at the intake end

of the air cleaner. Be careful not to damage

the fins. Make sure the element is seating

evenly. Tighten the element wing nut.

11. Install the dust cap with the arrows pointing

up. Tighten the clamp ring to hold it in place.

Check all intake hose connections for leaks

or abrasions.

12. Reset the air filter restriction indicator.

13. Close the access doors.

ENGINE--GAS/LP

6-7

7400 MM428 (2--94)

FUEL SYSTEM -- GASOLINE

FUEL FILTER

The fuel filter trap fuel contaminants. The filter is

located on the fuel line going into the carburetor.

Replace the filter elements every 400 hours of

operation.

CARBURETOR

The carburetor has two basic adjustments. Those

adjustments are idle fuel mixture and idle speed.

Check and adjust idle fuel mixture and idle speed

every 100 hours of operation.

FOR SAFETY: When Servicing Machine,

Keep Flames And Sparks Away From

Fuel System Service Area. Keep Area

Well Ventilated.

The idle speed is controlled by a screw located on

the side of the carburetor next to the throttle

linkage. Increase the engine speed by turning the

screw clockwise. Decrease the engine speed by

turning the screw counter--clockwise. Idle speed is

800 to 900 rpm for gasoline, and 900 to 1000 for

LPG, with no power to the electronic governor.

ENGINE--GAS/LP

6-8 7400 MM428 (12--98)

FUEL SYSTEM -- LPG

The liquid withdrawal LPG fuel system has

up of five components: the LPG fuel tank,

pressure relief valve, fuel filter lock,

vaporizer-regulator, and the carburetor.

Liquid LPG fuel flows from the LPG tank, under its

own pressure, to the pressure relief valve. Usually

this valve is closed, preventing LPG fuel from

escaping into the atmosphere. The valve opens to

relieve pressure if the fuel pressure exceeds

system limits. From the pressure relief valve, the

liquid LPG fuel flows to the fuel filter lock.

The fuel filter lock filters unwanted tank scale and

deposits out of the LPG fuel. The fuel filter lock

also stops the flow of LPG fuel when the engine is

not operating. The oil pressure switch controls the

fuel filter lock. When the engine oil pressure

is 35 kPa (5 psi) or greater, the oil pressure switch

permits an electrical current to open the fuel filter

lock which allows LPG fuel to flow on to the

vaporizer-regulator. The oil pressure switch is

bypassed when the engine is being started,

allowing LPG fuel to flow.

The vaporizer section of the vaporizer-regulator

converts the liquid LPG fuel into a gaseous LPG

fuel. From the vaporizer section, the gaseous

LPG fuel is sent to the primary regulator section

of the vaporizer-regulator. The primary regulator

section reduces the pressure of the LPG fuel. The

secondary regulator section reduces the LPG fuel

pressure to the level required by the carburetor.

From the vaporizer-regulator, the LPG fuel is sent

to the carburetor where it is finally metered into

the air flow sent to the engine combustion

chamber.

Never operate an LPG powered machine if the

LPG fuel system is leaking, or if any component in

the fuel system is malfunctioning. Operating the

machine under either of these conditions may

cause a fire or explosion.

ENGINE--GAS/LP

6-9

7400 MM428 (12--98)

Check for frosting. If frosting occurs on or near

any LPG component, there is a possible LPG fuel

leak or malfunctioning component.

To locate the leak, apply a soapy water solution to

the suspected area. Watch for bubbles forming in

this suspected area. This area may have an LPG

fuel leak. Repair or replace the part. Use Loctite

brand Stainless Steel PST thread sealant when

reassembling. Aging or high humidity does not

affect this epoxy-type sealant. Be sure to follow

application directions and apply proper torque

when reconnecting fittings. Never bypass safety

components except to test. If they are defective,

replace them before operating the machine.

Frosting does not occur before the engine

reaches operating temperature. Check after

engine reaches operating temperature.

Check routings of all LPG hoses. Keep them

away from sharp edges, exhaust manifolds, or

other hot surfaces. Check for signs of abrasion or

deterioration. Replace worn or damaged hoses.

ENGINE--GAS/LP

6-10 7400 MM428 (12--98)

LP FUEL TANKS

The LPG fuel tanks should be inspected for sharp

dents, gouges, leaks, and broken protecting rings

whenever the tanks are refilled. All tank valves

must be inspected for leaks using a soap solution.

Valves must also be checked for dirt, paint, or

other debris in the valve openings. The following

specific checks must also be made:

Filler Valve -- Check the valve for proper

functioning and the presence of the

handwheel. Valve must be closed except

during filling.

Liquid Service Valves -- Check the valve

for proper functioning and presence of the

handwheel. The valve must be closed

except when in service.

Tank Service Valve Coupling -- Check for

proper functioning, thread condition, and

damaged or missing washers or o-rings.

ENGINE--GAS/LP

6-11

7400 MM428 (12--98)

Safety Relief Valve -- Check for damage.

Check for the presence of the relief valve

elbow and the proper direction of the elbow.

If the rain cap is missing, check for foreign

matter and replace the rain cap. Do not

tamper with the relief valve setting.

Magnetic Liquid Level Gauge -- Check the

operation against the maximum filling point

as determined by weight.

An LPG fuel tank with any of the stated defects

must be removed from service and be repaired or

destroyed accordingly.

If an LPG fuel tank is damaged or leaking, it

should be removed to a designated safe area. Do

not attempt to make repairs to the tank,

regardless of condition. Qualified personnel must

make repairs or disposal.

The care an LPG fuel tank receives has a direct

bearing on how long that tank can be used safely.

LPG fuel tanks must not be dropped or dragged

across any surface. To move LPG fuel tanks, use

a hand truck or roll the tank on its foot ring while it

is being held in a position slightly off the vertical.

Whether the storage is inside or outside, fuel

tanks should not be stored near combustible

materials or high temperature sources such as

ovens and furnaces, since the heat may raise the

pressure of the fuel to a point where the safety

relief valves would function. Store the tanks in a

way that if the safety relief valves do function,

they will relieve vapor and not liquid.

ENGINE--GAS/LP

6-12 7400 MM428 (12--98)

Valves on empty tanks must be closed during

storage and transportation.

Similar precautions should be taken in storing

machines fitted with LPG fuel tanks. The

machines may be stored or serviced inside

buildings, provided there are no leaks in the fuel

system and the tanks are not overfilled. While

machines are being repaired inside a building, the

shut-off valve on the tank must be closed, except

when the engine has to be operated.

Changing the tank is a chance for the machine

operator to carefully check over the tank, fittings,

and the fuel lines and fittings. If abnormal wear is

detected, report the findings to the appropriate

personnel.

TO CHANGE AN LPG FUEL TANK

1. Park the machine in a designated safe area.

2. Close the tank service valve.

3. Operate the engine until it stops from lack of

fuel, then set the machine parking brake.

FOR SAFETY: Before Leaving Or

Servicing Machine: Stop On Level

Surface, Set The Parking Brake, Turn Off

Machine And Remove Key.

4. Put on gloves and remove the

quick-disconnect tank coupling.

5. Inspect the LPG fuel lines for wear or

damage.

6. Remove the empty LPG fuel tank from the

machine.

7. Check the tank for damage or wear.

8. Store the tank in a designated, safe area.

9. Select a filled LPG fuel tank and inspect it

for damage or leaks.

NOTE: Make sure the LPG fuel tank matches the

fuel system (liquid tank with liquid system).

ENGINE--GAS/LP

6-13

7400 MM428 (12--98)

10. Carefully put the LPG tank in the machine

so that the tank centering pin enters the

aligning hole in the tank collar.

NOTE: If you cannot line up the centering pin,

make sure you have the correct LPG fuel tank

and then adjust the pin locator in or out.

11. Fasten the tank hold-down clamp to lock the

tank in position.

12. Connect the LPG fuel line to the tank service

coupling. Make sure the service coupling is

clean and free of damage. Also make sure it

matches the machine service coupling.

13. Open the tank service valve slowly and

check for leaks. Close the service valve

immediately if an LPG leak is found, and tell

the appropriate personnel.

14. If no leaks are found, the engine is ready to

start.

ENGINE--GAS/LP

6-14 7400 MM428 (12--98)

FUEL FILTER LOCK

The fuel filter lock filters the LPG fuel. It also

stops the flow of LPG fuel to the engine when the

engine is not operating or when the engine oil

pressure is less than 35 kPa (5 psi).

VAPORIZER-REGULATOR

If any malfunction is found, completely

disassemble the vaporizer-regulator. Clean all the

parts in alcohol.

Inspect all the parts and replace where needed.

Carefully reassemble the vaporizer-regulator with

the seal repair kit. Check for proper operation.

CARBURETOR

If any malfunction is found, completely

disassemble the carburetor. Clean all the parts in

alcohol.

Inspect all the parts and replace where needed.

Carefully reassemble the carburetor with the seal

repair kit.

OIL PRESSURE SWITCH

The engine oil pressure switch requires no regular

maintenance. Never bypass the oil pressure

switch. The switch is a safety feature that

prevents LPG fuel from flowing when the engine

is not operating properly.

ENGINE--GAS/LP

6-15

7400 MM428 (12--98)

LPG FUEL TROUBLESHOOTING

Problem Cause Remedy

Engine will not start Outoffuel Replace fuel tank with full one

Service valve opened too quickly

-- check valve stopped fuel flow

Close service valve and reopen

slowly

Plugged fuel filter Replace filter

Kinked or restricted fuel line Straighten or replace fuel line

Engine out of tune Tune-up engine

Oil pressure switch failure Replace oil pressure switch

Fuel lock valve failure Repair or replace fuel filter lock

Vaporizer-regulator failure Repair or replace

vaporizer-regulator

Engine runs unevenly or lacks

power

Wrong type of fuel tank -- vapor

withdrawal tank

Replace vapor withdrawal tank

with liquid withdrawal tank

Plugged fuel filter Replace filter

Kinked or restricted fuel line Straighten or replace fuel line

Engine out of tune Tune-up engine

Restricted air filter Clean or replace air filter element

Vaporizer-regulator out of

adjustment

Adjust vaporizer-regulator

CYLINDER HEAD

A three-stage torque procedure should be used

when reassembling the cylinder head. Tighten the

cylinder head bolts seasonally. See Ford VSG

411/413 Engine Service Manual.

VALVE TAPPET CLEARANCE

Check and adjust the intake valve clearance to

0.22 mm (0.009 in), and the exhaust valve

clearance to 0.32 mm (0.013 in) while the engine

is cold the first 50 hours of operation and every

400 hours there after. See Ford VSG 411/413

Engine Service Manual.

CRANKCASE VENTILATION SYSTEM

Clean the crankcase ventilation hoses, tubes, and

fittings and replace the PCV valve every 400

hours of operation.

ENGINE--GAS/LP

6-16 7400 MM428 (12--98)

GOVERNOR TROUBLESHOOTING

1. The first step in this troubleshooting is to

disconnect the throttle linkage at the

carburetor and work the throttle at the

carburetor by hand.

If you can run the engine by hand and it

works with no problems, go to step four.

If the problem continues, it is not with the

governor, it is with the ignition signal fuel

systems or the engine itself.

2. Ignition Signal

The DIS engine has no distributor, but the

timing signals that drive the governor

originate from the Ignition Control input

leads. They are the Yellow Wire #71 and the

Yellow Wire #72. To test this, use the

governor test harness (TENNANT Part No.

66137). Once the harness is in place, use a

tach/dwell meter to test for the proper RPM’s

and a flat ignition signal. Test at the text plug

at either Pin C, or Pin D.

NOTE: An inductive RPM pickup won’t work for

this test.

NOTE: When checking the RPM’s at Pin C, and

Pin D, the ignition signal will be half of the total

RPM’s the engine is running at because of the

DIS system.

Your readings should be:

TOTAL READING--GAS

a. Start/Idle -- 800 RPM

b. I -- 1350¦50 RPM

c. II -- 2400¦50 RPM

TOTAL READING--LPG

a. Start/Idle -- 900 RPM

b. I -- 1350¦50 RPM

c. II -- 2400¦50 RPM

ENGINE--GAS/LP

6-17

7400 MM428 (12--98)

3. Fuel System

A common problem that has been

encountered on LPG machines is a

restricted fuel hose (a clogged fuel filter can

have the same effect).

If the governor opens the carburetor wide

open and the engine loses speed, the

problem is not in the governor. The fuel

system is at fault. The purpose of the

governor is to open the carburetor and to

bring the engine to set RPM’s depending on

where you have the speed control switch set

at.

After you have verified that the ignition

system and the fuel system are not at fault,

go to the next step.

ENGINE--GAS/LP

6-18 7400 MM428 (12--98)

(A) +

(B) --

(D) Signal

(E) Actuator +

(F) Actuator --

(G) Speed

(H) Speed

High=+9VDC

Low = 0VDC

+12VDC Switched (18D/ORA)

Ground (13E/BLK)

D.I.S.

Ignition

Module (72C/YEL)

(71C/YEL)

(84/GRN)

(83/BRN)

ELECTRONIC GOVERNOR WIRING PICTORIAL

Throttle actuator

(+)

(--)

(86/PUP)

(85/BLU)

Electronic

Instrument

Panel

A BCDEF G

TO: HARNESS TO: GOVERNOR

TEST PLUG

NOTE: The wire colors of the test harness do not necessarily match the machine harness.

ENGINE--GAS/LP

6-19

7400 MM428 (12--98)

5. System Grounds

The wire harness grounds on the machines

with a DIS engine are routed to the stud on

the alternator, and from there, a separate

cable is routed to the bolt on the bell housing

where the battery cable is attached.

If a bad ground is present, the engine will

tend to run over speed.

The machine must have good grounds

throughout from the battery cable to the

control box.

The battery cable must be clean and tight.

There must not be a greater voltage drop

than .2 volts between Pin B, on the test

harness, the engine, the alternator, and the

battery positive terminal and the battery

negative terminal.

To do this, take your voltmeter and set it on

the DC volts scale. Then with your positive

probe, clamp it to battery positive. Then with

the negative probe, move it to the

above-stated places on the machine.

The actuator is internally isolated and does

not require that the cable be grounded.

6. Start-Up Check

With the throttle switch in the engine start

position, turn the ignition switch to the on

position. The actuator should cycle the

carburetor lever once.

NOTE: A cycle is to move from the off or idle

position to the open position and then return to

the off or idle position.

If this does not happen, the power wiring to

the control box is probably at fault or the

control box is faulty. IT IS RARE TO HAVE

A FAULTY CONTROL BOX, so proceed

with the following voltage checks BEFORE

REPLACING IT.

7. Throttle Control Switch Check

If the engine doesn’t respond to the throttle

switch control:

a. With the engine running, disconnect

Wire 86, purple wire, at the actuator.

ENGINE--GAS/LP

6-20 7400 MM428 (12--98)

b. Connect a jumper wire from the battery

terminal on the starter to the terminal

where you removed Wire 86, purple

wire, from the actuator.

The engine should come up to operating

speed. If the engine comes up to speed,

replace the throttle control switch. If the

engine doesn’t respond, go to the next step.

8. Operating Voltage

The following voltage checks are done with

the machine not running and using a Fluke

or Beckman digital multimeter and the

governor test harness.

Throttle control switch in start/idle position:

Pin A -- Battery Voltage ¦.2

Pin B -- 0 -- this is a ground

Pin C -- Battery Voltage ¦.2

Pin D -- Battery Voltage ¦.2

Pin E -- Battery Voltage ¦.2

Pin F -- Battery Voltage ¦.2

Pin G -- Battery Voltage ¦.2

PinH--3to3.5VDC

Throttle control switch in the normal sweep

position:

Pin G -- <1VDC

PinH--7to9VDC

Throttle control switch in the Litter sweep position:

Pin G -- <1VDC

Pin H -- <1VDC

The following voltage and RPM readings are at

the electric control box using the test harness with

the machine running.

NOTE: when you are testing if you should be in

the DC or AC scale on your multimeter. You will

also need your tach/dwell for the RPM checks.

The readings are taken with either a Fluke or

Beckman digital multimeter:

ENGINE--GAS/LP

6-21

7400 MM428 (12--98)

Throttle control switch in the start/idle position:

Pin C -- 675 ¦100 RPM

Pin D -- 675 ¦100 RPM

Pin E -- Battery Voltage ¦.2

PinF--6to6.5VAC

Throttle control switch in the normal sweep

position:

Pin C -- 1100 ¦25 RPM

Pin D -- 1100 ¦25 RPM

Pin E -- Battery Voltage ¦.2

PinF--6.5to7VAC

Throttle control switch in the litter sweep position:

Pin C -- 1200 ¦25 RPM

Pin D -- 1200 ¦25 RPM

Pin E -- Battery Voltage ¦.2

PinF--7to7.5VAC

If you do not get these values:

Pin A -- Check battery, wiring/connections,

and also the charging system.

Pin B -- Check all grounds.

Pin C -- Check ignition system and fuel

systems.

Pin D -- Check ignition system and fuel

systems.

Pin E -- Possible control board.

Pin F -- Possible control board.

Pin G -- Possible switch.

Pin F -- Possible switch.

ENGINE--GAS/LP

6-22 7400 MM428 (3--02)

The volt readings at the actuator with the machine

running and using a Fluke or Beckman digital

multimeter:

At the terminal where Wire 84, green wire, is

hooked to:

Start/Idle -- 6 to 6.5 VAC ¦.2

Normal -- 6.5 to 7 VAC ¦.2

Litter -- 7 to 7.5 VAC ¦.2

At the terminal where Wire 86, purple wire, is

hooked to:

Start/Idle -- 12 to 14.5 VDC ¦.2

Normal--12to14.5VDC¦.2

Litter -- 12 to 14.5 VDC ¦.2

9. Control Box Adjustment

If all the above aspects, in particular the

linkage, have been verified and the warmed

up engine either:

a. Hunts at running speed with the

accessories off.

b. Responds very sluggishly to switch

changes, an adjustment change in the

control box may be necessary.

FOR ANALOG CONTROLLERS:

Cut and remove the RTV seal on the back of

the box.

A slight adjustment of the surge screw may

be necessary to correct the conditions

mentioned above. Turn the screw

approximately 2_at a time and wait for 30

seconds to verify the change. Be careful.

Only a slight change is necessary, and the

“pot” can be broken if too much force is

used.

ENGINE--GAS/LP

6-23

7400 MM428 (3--02)

After the control throttle response is

achieved, verify that the operating speeds

are correct and adjust, if necessary. After

the speeds are reset, the surge screw may

have to be readjusted.

In general, if a new box is being installed, a

gasoline-equipped machine may require that

the sensitivity be reduced slightly.

When the sensitivity is adjusted, the run

speed should not be affected. If the

adjustment is too great, the start speed will

be affected. Verify that the start speed is

correct.

If too much sensitivity is adjusted in, the

engine will either hunt in a no load condition

or over speed severely when the speed

switch is actuated.

If too little sensitivity is adjusted in, the

engine will seem sluggish. The engine speed

will drop off when the load is increased and

not recover promptly.

The engine speed should not drop off, but

you can have the three hunts of the engine.

If, for some reason, the sensitivity

adjustment became grossly maladjusted, a

good starting point can be obtained by

rotating the pot fully counterclockwise and

then back clockwise 45_.

After the adjustments are made and verified,

reassemble the back plate and reseat the plate

with a bead of RTV to keep dust and moisture out

of the box.

FOR DIGITAL CONTROLLERS:

See TO ADJUST GOVERNOR section of

this manual.

ENGINE--GAS/LP

6-24 7400 MM428 (3--02)

GOVERNOR

The electronic governor controls engine speed.

The governor consists of an ignition control

assembly, a control box, and an actuator mounted

on the engine. The ignition control assembly and

control box regulate the actuator, which in turn

controls the throttle.

The electronic governor is factory set and is not

user serviceable.

TO ADJUST GOVERNOR

1. Raise the front of the machine and place

jack stands under the frame.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack

stands.

2. Start the engine and warm to operating

temperature.

3. Move the speed switch to idle, all

accessories off.

4. Move the speed switch to the fast position.

5. For ANALOG CONTROLLER: If engine

speed surges occur, turn the surge

adjustment screw (located on back of

governor control box under hole plug)

counterclockwise one-eighth of a turn.

Repeat until surges do not occur.

Replace hole plug if removed for adjustment.

6. For DIGITAL CONTROLLER: Follow the

instructions on the DIGITAL CONTROLLER

SET--UP diagram.

7. Remove the jack stands and lower the

machine.

ENGINE--GAS/LP

6-25

7400 MM428 (3--02)

rocker down

Set DIP switches according to

controller label, before installing

controller.

123 45 6 78

DIGITAL CONTROLLER SET -- UP

ENGINE--GAS/LP

6-26 7400 MM428 (12--98)

IGNITION SYSTEM

SPARK PLUGS

Clean or replace, and set the gap of the spark

plugs every 400 hours of operation. A wire gauge

is best for checking the spark plug gap. A flat

gauge should not be used unless the electrode

surfaces have been dressed with a small file to

get parallel surfaces between the center and side

electrode. Set the spark plug gap by bending the

side electrode. All spark plugs, new or used,

should have the gaps checked and reset if

necessary.

The proper spark plug gap is 1 mm (0.040 in).

TO REPLACE SPARK PLUGS

FOR SAFETY: Before Leaving Or

Servicing Machine: Stop On Level

Surface, Set The Parking Brake, Turn Off

Machine And Remove Key.

1. Open the engine cover and side door.

2. Remove the spark plug wires from the four

spark plugs.

NOTE: Clean any dirt from the spark plug seat

area before removing the spark plugs.

3. Remove the spark plugs from the engine

4. Clean the spark plug seat in the cylinder

head.

5. Use a new seat gasket and screw the plug

in by hand.

6. Tighten the spark plugs with a socket

wrench of the correct size.

ENGINE--GAS/LP

6-27

7400 MM428 (3--02)

FORD DISTRIBUTORLESS IGNITION SYSTEM

SYNOPSIS

This is a troubleshooting guide for the Ford

Distributorless Ignition System.

Unlike a conventional system, the Ford

Distributorless Ignition System (DIS) uses two

coils that each fire one pair of spark plugs. The

spark plugs are also fired on both the power and

exhaust stroke.

The DIS system also uses a Universal Electronic

Spark Control (UESC) module which adjusts the

timing of the engine. The degree of timing change

needed is determined by electrical and vacuum

input to the UESC, these are:

The engine harness has a separate wire for the

gas and another for the LPG machines. Make

sure you connect the correct wire for the type of

fuel being used.

ENGINE LOAD -- FROM PRESSURE

REDUCER:

Located in the intake manifold.

Minimum 21 KPA (6.22” Hg)

Maximum 101 KPA (29.91” Hg)

ENGINE TEMPERATURE

The Engine Coolant Temperature Sensor (ECTS)

located in the intake manifold water jacket sends

engine temperature information to UESC.

Minimum --39_C38_F

Maximum 112_C 232_F

When the engine is starting, at 250 RPM or less,

the timing is set at 10_before top dead center

(BTDC).

ENGINE--GAS/LP

6-28 7400 MM428 (12--98)

RUN MODE

In this mode the RPM is above 250 and the spark

advance is calculated in three sections which are

added together to maintain optimum running

condition.

The Base Spark Advance (BSA) is calculated by

the UESC module looking at speed and load

inputs.

The Spark Advance Offset Temperature (SAOT)

will change ignition timing. This is determined by

the Engine Coolant Temperature (ECT). This

allows the spark advance to be altered during cold

engine conditions.

SERVICING AND TESTING

SERVICING:

1. Every 400 hours, remove the spark plugs

and clean and adjust the electrode.

2. Clean and visually check spark plug high

tension leads and test for resistance. The

Ohm meter should read between 9,000 and

16,000 Ohms.

TESTING:

Secondary Coil Testing

Remove the four (4) spark plug wires and

measure the secondary coil resistance by

placing the meter into plug wire terminal.

1 -- 4 at the coil

2 -- 3 at the coil

On each test you should read 14,000 + 50

Ohms.

Universal Spark Control Module Diaphragm

Testing

Using a vacuum pump, apply 15” Hg to the

UESC and vacuum inlet. The diaphragm

should hold the pressure. If it fails, replace

UESC unit.

To test the sensors and wiring harness,

follow the direction on the next three pages.

ENGINE--GAS/LP

6-29

7400 MM428 (12--98)

“FAILURE MODE OF DIS” IGNITION HARNESS

The Ford DIS Universal Spark Control was

checked for “poor connection”.

The results of open leads were:

Term 11 or 12 Ignition Coil Signal Leads --

The governor received 1/2 of its intended

signal and caused the actuator to hold the

carb arm wide open. At the same time, the

engine missed due to incorrect firing of

plugs, but the speed still climbed to about

3,000--4,000 rpm. When either of these

leads were opened at the start speed, the

engine missed slightly and rose to double

the start speed or about 3,000 rpm.

Term 9 Ground -- Any failure here killed the

engine instantly or caused the engine to

slow down if it were cycled.

Term 6 & 7 Octane Selector -- Opening

these terminals retards the spark in varying

degrees. Under light to moderate load

conditions, no adverse effect will take place.

However, run-on or pre-ignition may take

place.

Term 4 & 10 Coolant Sensor -- Contrary to

previous thoughts, opening the lead doesn’t

noticeably affect the engine. The timing only

changes a few degrees.

Term 2 & 3 Crank Position Sensor --

Opening either of these leads kills the

engine quickly and it will not start.

Term 8 Power Lead -- Opening this lead kills

the engine and it will not start.

In summary, no alarming effect happens except if

the coil signal leads are interrupted. These are the

end leads on the module and if the harness has

too much tension on it, the signal will become

intermittent and cause the engine to overspeed.

The only obvious damage will probably occur to

the propelling pump, as the fan is rated for

operation to 10,000 rpm. If the acc. are on when

the lead becomes intermittent, the engine will not

develop enough power to overspeed excessively.

ENGINE--GAS/LP

6-30 7400 MM428 (12--98)

200---600

Ohms

VRS +

V R S ---

65 Blue

66 Green

Variable reluctance

sensor (crank position

sensor)

Ohms

105,000

ECT1

ECT2

67 Orange

10K Ohm

70 Green

64 Brown

Engine coolant

temperature sensor in

ice water bath

See Engine Coolant

Sensor chart

OCT2

OCT1

68 Brown

Cut and ground to set octane (retard

spark advance)

18T Orange

12.6

Volts +

D . C . ---

VBatt

Power Ground

16M 16I

13PP Black

Ignition

switch on

13QQ Black

Batt

12.6 V

---

0.5 --- 1.0

Ohms

CDO

(Phase

CDO

(Phase

852

71 Yellow

72 Gray

850A

852A

HT HT

Distributorless

Ignition Coil

12.6

Volts +

D . C . ---

Remove the coil connector and probe

the center female terminal

To Pi n #9

FORD DIS IGNITION

ENGINE--GAS/LP

6-31

7400 MM428 (12--98)

ENGINE COOLANT SENSOR

Temperature

_C_F

Sensor (Ohms)

+.02_

Sensor & Harness

(Ohms) + .03_

-- 3 0 --- 2 2 481,000 491,000

-- 2 0 4271,000 281,000

-- 1 0 14 158,000 168,000

032 95,000 105,000

10 50 58,750 68,750

20 68 37,300 47,300

30 86 24,270 34,270

40 104 16,150 26,150

50 122 10,970 20,970

60 140 7,600 17,600

70 158 5,360 15,360

80 176 3,840 13,840

90 194 2,800 12,800

100 212 2,070 12,070

110 230 1,550 11,550

120 248 1,180 11,180

130 266 930 10,930

140 284 701 10,701

150 302 550 10,550

ENGINE--GAS/LP

6-32 7400 MM428 (12--98)

TO REPLACE ENGINE ALTERNATOR

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine engine cover and side

door. Remove the side door from the

machine.

3. Remove the two hex screws holding the

plastic fan belt cover to the front of the

engine. Remove the cover.

4. Disconnect the wires from the back of the

alternator.

5. Remove the hex screw from the top of the

alternator.

6. Loosen the lower hex screw and nyloc nut

and push the alternator in toward the engine.

Remove the V--belt from the alternator drive

pulley.

7. Remove the hex screw and nyloc nut from

the bottom of the alternator. Remove the

alternator.

8. If the new alternator does not have a drive

pulley----remove the hex nut and washer

holding the drive pulley to the old alternator.

Install the drive pulley on the new alternator

and tighten tight.

9. Install the new alternator back in the

machine. Reinstall the lower hex screw and

nyloc nut. Leave loose for now.

10. Reinstall the hex screw in the upper arm and

the top of the alternator. Leave loose for

now.

ENGINE--GAS/LP

6-33

7400 MM428 (12--98)

11. Reinstall the V--belt on the alternator drive

pulley.

12. Pull the alternator away from the engine to

tighten the V--belt. Tighten the upper hex

screw tight.

13. Reconnect the wires to the back of the new

alternator. See schematic in the

ELECTRICAL section.

14. Reinstall the plastic belt cover to the front of

the engine. Hand tighten the hex screws

tight.

15. Reconnect the battery cables, close the

operators seat and start the machine.

16. Check the new alternator for proper

operation.

ENGINE--GAS/LP

6-34 7400 MM428 (12--98)

TO REPLACE ENGINE STARTER

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

3. If the machine is an LPG, remove the LP

tank from the cradle.

4. The vacuum fan assembly can be removed

for better access to the starter. See TO

REMOVE VACUUM FAN instructions in the

SCRUBBING section.

5. Remove the air cleaner intake tube from the

air cleaner and machine frame.

6. Reach in through the left side of the engine

and disconnect the battery cable and

electrical wires leading to the starter.

7. Reach in through the open seat support area

and remove the three M10 hex screws

holding the starter to the bellhousing.

NOTE: The bottom hex screw has a nyloc nut on

the starter side.

8. Remove the starter out through the area of

the vacuum fan and engine oil filter.

9. Position the new starter in the machine.

10. Reinstall the three M10 hex screws and one

nyloc nut. The nyloc nut goes on the bottom

hex screw. Tighten to 31 -- 40 Nm

(27 -- 35 ft lb).

11. Reconnect the battery cable and electrical

wires to the starter. See schematic in the

ELECTRICAL section.

ENGINE--GAS/LP

6-35

7400 MM428 (12--98)

12. Reinstall the air cleaner intake tube to the air

cleaner and machine frame.

13. If the vacuum fan was removed----reinstall.

See TO INSTALL VACUUM FAN

instructions in the SCRUBBING section.

14. Reconnect the battery cables to the battery

and close the operators seat.

15. If the machine is an LPG----reinstall the LP

tank.

16. Reinstall the engine side door and close the

covers.

17. Start the machine.

TO REMOVE ENGINE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Pivot the operators seat to the open position

and engage the prop rod.

2. Disconnect the battery cables and remove

the battery.

NOTE: The battery tray can also be removed for

better access to the propel pump.

3. Remove the detergent tank and the rubber

sound flap from the machine.

4. Remove the two hex screws holding the

propel pump to the engine bellhousing

NOTE: The main suction line to the accessory

pump is held, by plastic ties, in a bundle of hoses

near the main valve. Remove the plastic ties to

gain slack in the suction line to ease pump

removal.

ENGINE--GAS/LP

6-36 7400 MM428 (12--98)

5. Remove the two hex screws holding the

hydraulic flow valve to the back, left of the

bellhousing. Do not disconnect any hydraulic

hoses.

6. Pull the propel pump out of the bellhousing

and drive coupler. Do not disconnect any

hydraulic hoses.

7. If the machine is an LPG, remove the LP

tank from the cradle.

8. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

9. Remove the vacuum hose from the vacuum

fan and the recovery tank.

10. The vacuum fan assembly can be removed

for better access to the engine. See TO

REMOVE VACUUM FAN instructions in the

SCRUBBING section.

NOTE: The engine hood must be supported in the

open position before the next step can be

completed.

11. Remove the clips on the bottom of the

engine hood gas springs. Remove the gas

springs from the ball studs on the support

channel.

12. Remove the hex screws holding the support

channel to the tank lintel and hood lintel.

Remove the support channel from the

machine.

13. Drain the radiator coolant.

14. Remove the radiator hoses where they

connect to the engine.

15. Drain the engine oil.

NOTE: Disconnect the engine oil drain hose from

the oil pan before lifting the engine completely out

of the machine.

ENGINE--GAS/LP

6-37

7400 MM428 (12--98)

16. Disconnect the exhaust pipe at the engine

manifold.

17. Disconnect the wire harness from all of the

engine components and place it out of the

way.

18. Disconnect the engine ground strap from

frame.

19. Disconnect the battery cable and electric

wires from the engine starter.

20. Disconnect the fuel line at the fuel pump on

a gas machine.

21. Disconnect the fuel line from the LP tank at

fuel lockoff / vaporizer on an LPG machine.

22. Using an overhead hoist, hook a chain or

strap through two or three pick--up points on

the engine. Put a slight amount of tension on

the chain.

23. Remove the three M12 hex screws and

nyloc nuts holding the motor mounts to the

rubber isolators on the machine frame.

24. Engine can now be carefully lifted out.

ENGINE--GAS/LP

6-38 7400 MM428 (12--98)

TO INSTALL ENGINE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Using a overhead hoist, hook a chain or

strap through two or three pick--up points on

top of the engine. Carefully position the

engine back in the engine compartment.

2. Carefully Lower the engine assembly down

on the the motor mounts.

NOTE: Make sure the hoses, wire harness,

exhaust pipe, and propel pump are pulled back

out of the way when lowering the engine

assembly in place.

3. Reinstall the three M12 hex screws in the

three motor mount isolators. Tighten to

64 -- 83 Nm (50 -- 60 ft lb)

4. Reconnect the ground cable from the

bellhousing to the machine frame.

5. Reinstall the flow valve on the back, left of

the bellhousing.

6. Reconnect the battery cable and electrical

wires to the starter. See schematic in the

ELECTRICAL section.

7. Reconnect the wire harness to engine

components, alternator, governor actuator,

oil switch, temperature sender, distributor,

and ignition module. See schematic in the

ELECTRICAL section.

8. Reinstall the propel pump back in the

bellhousing. Use a small amount of blue

loctite 242 on the threads. Reinstall the two

hex screws. Tighten to 64 -- 83 Nm

(50 -- 60 ft lb).

NOTE: Make sure the splines on pump line up

with splines in coupler when installing pump.

9. Reinstall the detergent tank in the seat

support area.

10. Reinstall the battery tray and battery.

11. Reinstall the exhaust pipe back on the

manifold. Reinstall the muffler clamp and

tighten tight.

ENGINE--GAS/LP

6-39

7400 MM428 (12--98)

12. Reconnect the fuel line at the fuel pump on

a gas machine.

13. Reconnect the fuel line from the LP tank at

fuel lockoff / vaporizer on an LPG machine.

14. Fill the engine with the proper grade of oil.

15. Reinstall the radiator hoses to the engine

and fill the radiator with coolant. See TO

PURGE AIR FROM RADIATOR instructions.

16. If the vacuum fan was removed----reinstall.

See TO INSTALL VACUUM FAN

instructions in the SCRUBBING section.

17. Reinstall the vacuum hose on the recovery

tank and vacuum housing.

18. Reinstall the support channel to the tank

lintel and hood lintel. Reinstall the four hex

screws and tighten to 18 -- 24 Nm

(15 -- 20 ft lb).

19. Reinstall the engine hood gas springs on the

ball studs on the support channel. Reinstall

the two clips.

20. Reconnect the battery cables.

21. Disengage the prop rod and lower the seat.

22. Reinstall the LP tank on a LPG machine.

23. Jack up the front of the machine and place

jack stands under the frame.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack stands

24. Start the machine. Check the engine,

hydraulic motors, and pumps for leaks.

25. Reinstall the engine side door and close the

covers.

ENGINE--GAS/LP

6-40 7400 MM428 (12--98)

TO PURGE AIR FROM RADIATOR

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Make sure that both radiator hoses are

connected to the engine.

2. Remove the radiator cap and pour in

approximately 1--1/2 gallons of coolant.

3. Open the engine cover and side door.

4. Loosen the hose clamp on the upper

radiator hose. Thisisthehoseonthe

thermostat housing.

5. Break the hose loose from the neck of the

thermostat housing and slowly pull the hose

off the neck.

6. Keep the hose off the neck until coolant

starts to flow out of the hose.

7. Quickly place the hose back on the neck of

the thermostat housing. Re--tighten the hose

clamp.

8. Start the machine and run it to operating

temperature. Shut off the engine.

9. Let the machine cool down for and carefully

re--check the level of the radiator coolant.

There should be enough room to poor

another 1/2 gallon of coolant in. If

not----repeat steps 4 thru 8.

10. If the machine overheats----repeat steps 4

thru 8.

NOTE: There may be air trapped in one of the

radiator hoses. It might take one or two tries to

completely purge all of the air from the cooling

system.

ENGINE--DIESEL

7-1

7400 MM428 (9--01)

CONTENTS

Page

LUBRICATION 7-3........................

ENGINE OIL 7-3.......................

COOLING SYSTEM 7-3...................

ENGINE FAN BELT 7-4.................

AIR INTAKE SYSTEM 7-4.................

AIR FILTER INDICATOR 7-4............

AIR FILTER 7-4.......................

TO REPLACE AIR FILTER ELEMENT 7-5

FUEL SYSTEM 7-6.......................

FUEL FILTER 7-6......................

TO REPLACE THE FUEL FILTER

CARTRIDGE 7-6....................

FUEL LINES 7-7.......................

TO PRIME FUEL SYSTEM 7-7..........

TO REPLACE ENGINE ALTERNATOR 7-8..

TO REPLACE ENGINE STARTER 7-10.....

TO REMOVE ENGINE 7-12................

TO INSTALL ENGINE 7-14................

TO PURGE AIR FROM RADIATOR 7-16....

DIESEL ENGINE SERVICE MANUAL

KUBOTA V1505 B (E)

TENNANT Part Number 84660

ENGINE--DIESEL

7-2 7400 MM428 (12--98)

ENGINE--DIESEL

7-3

7400 MM428 (12--98)

INTRODUCTION

This section includes repair information on the

engine and related systems, such as fuel,

electrical, and drive belts.

ENGINE--DIESEL

7-4 7400 MM428 (12--98)

LUBRICATION

ENGINE OIL

Check the engine oil level daily. Change the

engine oil and oil filter every 100 hours of machine

operation. Use 10W30 SAE--CC/CD rated engine

oil.

Fill the engine with oil to the level indicated on the

oil dipstick. The engine oil capacity is 6 L (6.3 qt)

with out the oil filter.

COOLING SYSTEM

Check the radiator coolant level every 100 hours

of operation. Use clean water mixed with a

permanent-type, ethylene glycol antifreeze to a

-- 3 4 _C(--30_F) rating.

FOR SAFETY: When Servicing Machine,

Avoid Contact With Hot Engine Coolant.

ATTENTION! Never pour cold water or

cold antifreeze into the radiator of an

overheated engine. Allow the engine to

cool down to avoid cracking the

cylinder head or block. Keep the engine

running while adding water.

Check the radiator hoses and clamps every 200

hours of operation. Tighten the clamps if they are

loose. Replace the hoses and clamps if the hoses

are cracked, harden, or swollen.

Check the radiator core exterior and hydraulic

cooler fins for debris every 100 hours of

operation. Blow or rinse all dust, which may have

collected on the radiator, in through the grille and

radiator fins, opposite the direction of normal air

flow. The grille and hydraulic cooler open for

easier cleaning. Be careful not to bend the cooling

fins when cleaning. Clean thoroughly to prevent

the fins becoming encrusted with dust. Clean the

radiator and cooler only after the radiator has

cooled to avoid cracking.

FOR SAFETY: When Servicing Machine,

Wear Eye And Ear Protection When

Using Pressurized Air Or Water.

Flush the radiator and the cooling system every

400 hours of operation, using a dependable

cleaning compound.

ENGINE--DIESEL

7-5

7400 MM428 (12--98)

ENGINE FAN BELT

The engine fan belt is driven by the engine

crankshaft pulley and drives the alternator pulley.

Proper belt tension is obtained when the belt

deflects 7 to 9 mm (0.28 to 0.35 in) from a force

of 10 kg (22 lb) applied at the mid-point of the

longest span.

Check and adjust the belt tension every 100 hours

of operation.

WARNING: Moving belt and fan. Keep

away.

AIR INTAKE SYSTEM

AIR FILTER INDICATOR

The air filter indicator shows when to clean or

replace the air filter element. Check the indicator

daily. The indicator’s red line will move as the air

filter element fills with dirt. Do not clean or replace

the air filter element until the red line reaches 5

kPa (20 in H2O) and the ”SERVICE WHEN RED”

window is filled with red. The indicator’s red line

may return to a lower reading on the scale when

the engine shuts off. The red line will return to a

correct reading after the engine runs for a while.

Reset the air filter indicator by pushing the reset

button on the end of the indicator after cleaning or

replacing the air filter element.

AIR FILTER

The engine air filter housing has a dust cap and a

dry cartridge-type air filter element. Empty the

dust cap daily. The air filter must be replaced

whenever the filter element is damaged or has

been cleaned three times.

Machines with the heavy duty air filter option have

a safety element. It is inside the standard

element. Replace, do not clean this element after

the regular element has been damaged or

cleaned three times.

Service the air filter element only when the air

filter indicator shows restriction in the air intake

system. Do not remove the air filter element

unless it is restricting air flow.

ENGINE--DIESEL

7-6 7400 MM428 (12--98)

TO REPLACE AIR FILTER ELEMENT

FOR SAFETY: Before Leaving Or

Servicing Machine: Stop On Level

Surface, Set The Parking Brake, Turn Off

Machine And Remove Key.

1. Open the engine cover and side door.

2. Unscrew the clamp ring on the filter.

3. Remove the dust cap.

4. Empty the dust cap.

5. Remove the filter wing nut.

6. Pull the filter element out of the filter

housing.

7. Clean the interior of the air cleaner housing

with a camp cloth. Clean the element

housing sealing surfaces.

8. Using an air hose, direct dry, clean air

maximum 205 kPa (30 psi) up and down

pleats on the inside of the filter. Do not rap,

tap, or pound dust out of the element.

FOR SAFETY: When Servicing Machine,

Wear Eye And Ear Protection When

Using Pressurized Air Or Water.

9. After cleaning the air filter element, inspect it

for damage by placing a bright light inside.

The slightest rupture requires replacement

of the filter. Clean and inspect the seals on

the ends of the element. They should be

unbroken and flexible. Remember to replace

the element after cleaning it three times.

10. Install the new or cleaned filter element so

the fins on the element are at the intake end

of the air cleaner. Be careful not to damage

the fins. Make sure the element is seating

evenly. Tighten the element wing nut.

11. Install the dust cap with the arrows pointing

up. Tighten the clamp ring to hold it in place.

Check all intake hose connections for leaks

or abrasions.

12. Reset the air filter restriction indicator.

13. Close the access doors.

ENGINE--DIESEL

7-7

7400 MM428 (12--98)

FUEL SYSTEM -- DIESEL

The diesel fuel system is made up of five basic

components which are: fuel tank, fuel filter/water

trap, fuel pump, injection pump, and injectors.

Fuel flows from the fuel tank through the fuel filter/

water trap. The water trap-filter separates water

and impurities from the fuel. From the fuel water

trap-filter, fuel is drawn through the electric fuel

pump and pumped to the injection pump. The

injection pump pressurizes and sends fuel to the

injectors. The injectors atomize and inject proper

amounts of fuel into the combustion chamber at

the proper times. Excess fuel is returned to the

fuel tank through an overflow pipe.

FUEL FILTER

The fuel filter cartridge filters impurities from the

fuel. It is located low on the left side of the engine

block

TO REPLACE THE FUEL FILTER CARTRIDGE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, And Turn

Off Machine.

1. Loosen the unit vent plug and open the

water trap drain to drain diesel fuel.

2. Remove the filter cartridge from the filter

head.

3. Lubricate the o-ring of the new filter

cartridge and spin it onto the filter head.

4. Bleed the fuel lines of air as described in TO

PRIME FUEL SYSTEM instructions.

ENGINE--DIESEL

7-8 7400 MM428 (12--98)

FUEL LINES

Check the fuel lines every 50 hours of operation.

If the clamp band is loose, apply oil to the screw

of the band, and securely tighten the band.

The rubber fuel lines can become worn-out

whether the engine has been used much or not.

Replace the fuel lines and clamp bands every two

years.

If the fuel lines and clamp bands are found worn

or damaged before two years’ time, replace or

repair them at once. Bleed the fuel system after

replacement of any of the fuel lines, see TO

PRIME THE FUEL SYSTEM. When the fuel lines

are not installed, plug both ends with clean cloth

or paper to prevent dirt from entering the lines.

Dirt in the lines can cause fuel injection pump

malfunction.

PRIMING FUEL SYSTEM

Typical diesel fuel systems require priming to

remove pockets of air in the fuel lines and fuel

components. This is usually required after running

out of fuel, changing fuel filter elements or

repairing a fuel system component. Air in the fuel

system prevents smooth engine operation.

This fuel system however is self-priming. The

return line comes from the top of the injector that

causes all air to escape through the return line.

TO PRIME FUEL SYSTEM

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, And Turn

Off Machine.

1. Make sure the fuel tank is full.

2. Open the air vent on top of the fuel filter.

3. Start the engine, operate it for one minute,

then stop it; or operate the starter motor in

ten-second intervals until a steady stream of

fuel flows from the vent.

4. Close the air vent and shut off the engine.

5. Clean up any fuel that was spilled during the

bleeding process.

ENGINE--DIESEL

7-9

7400 MM428 (12--98)

TO REPLACE ALTERNATOR ON DIESEL

ENGINE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine engine cover and side

door. Remove the side door from the

machine.

3. Remove the two hex screws holding the fan

belt cover to the front of the engine. Remove

the cover.

4. Disconnect the wires from the back of the

alternator.

5. Remove the hex screw from the top of the

alternator.

6. Loosen the lower hex screw and nyloc nut

and push the alternator in toward the engine.

Remove the V--belt from the alternator drive

pulley.

7. Remove the hex screw and nyloc nut from

the bottom of the alternator. Retain the

spacer. Remove the alternator.

8. If the new alternator does not have a drive

pulley----remove the hex nut and washer

holding the drive pulley to the old alternator.

Install the drive pulley on the new alternator

and tighten tight.

9. Install the new alternator back in the

machine. Reinstall the lower hex screw,

spacer, and nyloc nut. Leave loose for now.

10. Reinstall the hex screw in the upper arm and

the top of the alternator. Leave loose for

now.

ENGINE--DIESEL

7-10 7400 MM428 (12--98)

11. Reinstall the V--belt on the alternator drive

pulley.

12. Pull the alternator away from the engine to

tighten the V--belt. Tighten the upper hex

screw tight.

13. Reconnect the wires to the back of the new

alternator. See schematic in the

ELECTRICAL section.

14. Reinstall the belt cover to the front of the

engine. Hand tighten the hex screws tight.

15. Reconnect the battery cables, close the

operators seat and start the machine.

16. Check the new alternator for proper

operation.

ENGINE--DIESEL

7-11

7400 MM428 (12--98)

TO REPLACE STARTER ON DIESEL ENGINE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake, Turn Off

Machine And Remove Key.

1. Raise the operators seat, engage the prop

rod, and disconnect the battery cables from

the battery.

2. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

3. The vacuum fan assembly can be removed

for better access to the starter. See TO

REMOVE VACUUM FAN instructions in the

SCRUBBING section.

4. Remove the air cleaner intake tube from the

air cleaner and machine frame.

5. Reach in through the left side of the engine

and disconnect the battery cable and

electrical wires leading to the starter.

6. Reach in through the left side of the engine

and remove the two hex screws holding the

starter to the bellhousing.

7. Remove the starter out through the area of

the vacuum fan and engine oil filter.

8. Position the new starter in the machine.

9. Reinstall the two hex screws and tighten to

18 -- 24 Nm (15 -- 20 ft lb).

10. Reconnect the battery cable and electrical

wires to the starter. See schematic in the

ELECTRICAL section.

ENGINE--DIESEL

7-12 7400 MM428 (12--98)

11. Reinstall the air cleaner intake tube to the air

cleaner and machine frame.

12. If the vacuum fan was removed----reinstall.

See TO INSTALL VACUUM FAN

instructions in the SCRUBBING section.

13. Reconnect the battery cables to the battery

and close the operators seat.

14. Reinstall the engine side door and close the

covers.

15. Start the machine.

ENGINE--DIESEL

7-13

7400 MM428 (12--98)

TO REMOVE DIESEL ENGINE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Pivot the operators seat to the open position

and engage the prop rod.

2. Disconnect the battery cables and remove

the battery.

NOTE: The battery tray can also be removed for

better access to the propel pump

3. Remove the detergent tank and the rubber

sound flap from the machine.

4. Remove the two hex screws holding the

propel pump to the engine bellhousing

NOTE: The main suction line to the accessory

pump is held, by plastic ties, in a bundle of hoses

near the main valve. Remove the plastic ties to

gain slack in the suction line to ease pump

removal.

5. Remove the two hex screws holding the

hydraulic flow valve to back, left of the

engine mount. Do not disconnect any

hydraulic hoses.

6. Pull the propel pump out of the bellhousing

and drive coupler. Do not disconnect any

hydraulic hoses.

7. Open the machine front cover, engine cover,

and side door. Remove the side door from

the machine.

8. Remove the vacuum hose from the vacuum

fan and the recovery tank.

9. The vacuum fan assembly can be removed

for better access to the engine. See TO

REMOVE VACUUM FAN instructions in the

SCRUBBING section.

NOTE: The engine hood must be supported in the

open position before the next step can be

completed.

10. Remove the clips on the bottom of the

engine hood gas springs. Remove the gas

springs from the ball studs on the support

channel.

ENGINE--DIESEL

7-14 7400 MM428 (12--98)

11. Remove the hex screws holding the support

channel to the tank lintel and hood lintel.

Remove the support channel from the

machine.

12. Drain the radiator coolant.

13. Remove the radiator hoses where they

connect to the engine.

14. Drain the engine oil.

NOTE: Disconnect the engine oil drain hose from

the oil pan before lifting the engine completely out

of the machine.

15. Disconnect the exhaust pipe at the engine

manifold.

16. Disconnect the wire harness from all of the

engine components and place it out of the

way.

17. Disconnect the engine ground strap from

frame.

18. Disconnect the battery cable and electric

wires from the engine starter.

19. Disconnect the fuel line at the fuel

filter/water separator on the left side of the

engine. Disconnect the small fuel return line.

20. Using an overhead hoist, hook a chain

through two pick--up points on the engine.

Put a slight amount of tension on the chain.

21. Remove the three M12 hex screws and

nyloc nuts holding the motor mounts to the

rubber isolators on the machine frame.

22. Engine can now be carefully lifted out.

ENGINE--DIESEL

7-15

7400 MM428 (12--98)

TO INSTALL DIESEL ENGINE

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Using a overhead hoist, hook a chain

through the two pick--up points on top of the

engine. Carefully position the engine back in

the engine compartment.

2. Carefully Lower the engine assembly down

on the the motor mounts.

NOTE: Make sure the hoses, wire harness,

exhaust pipe, and propel pump are pulled back

out of the way when lowering the engine

assembly in place.

3. Reinstall the three M12 hex screws in the

three motor mount isolators. Tighten to

64 -- 83 Nm (50 -- 60 ft lb)

4. Reconnect the ground cable from the

bellhousing to the machine frame.

5. Reinstall the flow valve on the back, left of

the bellhousing.

6. Reconnect the battery cable and electrical

wires to the starter. See schematic in the

ELECTRICAL section.

7. Reconnect the wire harness to engine

components, alternator, governor actuator,

oil switch, and temperature sender. See

schematic in the ELECTRICAL section.

8. Reinstall the propel pump back in the

bellhousing. Use a small amount of blue

loctite 242 on the threads. Reinstall the two

hex screws. Tighten to 64 -- 83 Nm

(50 -- 60 ft lb).

NOTE: Make sure the splines on pump line up

with splines in coupler when installing pump.

9. Reinstall the detergent tank in the seat

support area.

10. Reinstall the battery tray and battery.

11. Reinstall the exhaust pipe back on the

manifold. Reinstall the muffler clamp and

tighten tight.

ENGINE--DIESEL

7-16 7400 MM428 (12--98)

12. Reconnect the fuel line at the fuel filter/water

separator on the left side of the engine.

13. Fill the engine with the proper grade of oil.

14. Reinstall the radiator hoses to the engine

and fill the radiator with coolant. See TO

PURGE AIR FROM RADIATOR instructions.

15. If the vacuum fan was removed----reinstall.

See TO INSTALL VACUUM FAN

instructions in the SCRUBBING section.

16. Reinstall the vacuum hose on the recovery

tank and vacuum housing.

17. Reinstall the support channel to the tank

lintel and hood lintel. Reinstall the four hex

screws and tighten to 18 -- 24 Nm

(15 -- 20 ft lb).

18. Reinstall the engine hood gas springs on the

ball studs on the support channel. Reinstall

the two clips.

19. Reconnect the battery cables.

20. Disengage the prop rod and lower the seat.

21. Jack up the front of the machine and place

jack stands under the frame.

FOR SAFETY: Block machine tires

before jacking machine up. Jack

machine up at designated locations

only. Block machine up with jack stands

22. Start the machine. Check the engine,

hydraulic motors, and pumps for leaks.

23. Reinstall the engine side door and close the

covers.

ENGINE--DIESEL

7-17

7400 MM428 (12--98)

TO PURGE AIR FROM RADIATOR

FOR SAFETY: Before Leaving Or

Servicing Machine; Stop On Level

Surface, Set Parking Brake., Turn Off

Machine And Remove Key.

1. Make sure that both radiator hoses are

connected to the engine.

2. Remove the radiator cap and pour in

approximately 1--1/2 gallons of coolant.

3. Open the engine cover and side door.

4. Loosen the hose clamp on the upper

radiator hose. This is the hose on the

thermostat housing.

5. Break the hose loose from the neck of the

thermostat housing and slowly pull the hose

off the neck.

6. Keep the hose off the neck until coolant

starts to flow out of the hose.

7. Quickly place the hose back on the neck of

the thermostat housing. Re--tighten the hose

clamp.

8. Start the machine and run it to operating

temperature. Shut off the engine.

9. Let the machine cool down for and carefully

re--check the level of the radiator coolant.

There should be enough room to poor

another 1/2 gallon of coolant in. If

not----repeat steps 4 thru 8.

10. If the machine over heats----repeat steps 4

thru 8.

NOTE: There may be air trapped in one of the

radiator hoses. It might take one or two tries to

completely purge all of the air from the cooling

system.

ENGINE--DIESEL

7-18 7400 MM428 (12--98)

7400 Service Manual Tennant Rider Floor Scrubber

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