OIL CLUTCH ASSEMBLY

H3.50-5.00XL (H70-110XL);

S6.00-7.00XL (S135-150XL) [B024]

PART NO. 897116

1200 SRM 334

SAFETY PRECAUTIONS

MAINTENANCE AND REPAIR

• When lifting parts or assemblies, make sure all slings, chains, or cables are correctly

fastened, and that the load being lifted is balanced. Make sure the crane, cables, and
chains have the capacity to support the weight of the load.

• Do not lift heavy parts by hand, use a lifting mechanism.

• Wear safety glasses.

• DISCONNECT THE BATTERY CONNECTOR before doing any maintenance or repair

on electric lift trucks.

• Disconnect the battery ground cable on internal combustion lift trucks.

• Always use correct blocks to prevent the unit from rolling or falling. See HOW TO PUT

THE LIFT TRUCK ON BLOCKS in the Operating Manual or the Periodic Mainte-
nance section.

• Keep the unit clean and the working area clean and orderly.

• Use the correct tools for the job.

• Keep the tools clean and in good condition.

• Always use HYSTER APPROVED parts when making repairs. Replacement parts

must meet or exceed the specifications of the original equipment manufacturer.

• Make sure all nuts, bolts, snap rings, and other fastening devices are removed before

using force to remove parts.

• Always fasten a DO NOT OPERATE tag to the controls of the unit when making repairs,

or if the unit needs repairs.

• Be sure to follow the WARNING and CAUTION notes in the instructions.

• Gasoline, Liquid Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Diesel fuel

are flammable. Be sure to follow the necessary safety precautions when handling these
fuels and when working on these fuel systems.

• Batteries generate flammable gas when they are being charged. Keep fire and sparks

away from the area. Make sure the area is well ventilated.

NOTE:

The following symbols and words indicate safety information in this

manual:

WARNING

Indicates a condition that can cause immediate death or injury!

CAUTION

Indicates a condition that can cause property damage!

Oil Clutch Assembly

Table of Contents

TABLE OF CONTENTS

General ...............................................................................................................................................................

1

Description .........................................................................................................................................................

1

Oil Clutch Assembly Repair ..............................................................................................................................

5

Remove and Disassemble ..............................................................................................................................

5

Clean and Inspect ..........................................................................................................................................

6

Assemble and Install .....................................................................................................................................

6

Clutch Pedal and Linkage Adjustment.............................................................................................................

9

Bypass Valve Adjustment for Cold Oil..............................................................................................................

9

Troubleshooting..................................................................................................................................................

10

This section is for the following models:

H3.50-5.00XL (H70-110XL) S6.00-7.00XL (S135-150XL) [B024]

©2003 HYSTER COMPANY

i

"THE

QUALITY

KEEPERS"

HYSTER

APPROVED

PARTS

1200 SRM 334

Description

General

This section has the description and repair procedures for the oil clutch system.

NOTE: The oil clutch and manual transmission is not available after 1996.

Description

The function of the clutch is to connect and discon-
nect the power from the engine to the transmission.
The clutch disc has splines and it slides on the
splines of the clutch shaft. See Figure 1. The pres-
sure plate cover is fastened to the engine flywheel
by capscrews. There are coil springs between the
cover and the pressure plate. When the pressure
plate pushes the clutch disc against the flywheel,
the clutch disc must turn with the flywheel.

The release mechanism has four levers that pull the
pressure plate toward the cover. This action com-
presses the coil springs and releases the tension of
the pressure plate on the clutch disc. The levers turn
with the cover. Because the linkage to the clutch
pedal does not turn, a release bearing is needed to
operate the clutch levers.

The clutch is also used for inching. When inching,
the release mechanism does not fully release the
force of the pressure plate on the clutch disc. The
clutch disc turns at a different speed than the fly-
wheel. Because the pressure plate and flywheel are

touching the clutch disc, the parts get hot. The oil
supply tube sends hydraulic oil to the clutch assem-
bly to cool the parts. The clutch housing is the sump
for the clutch hydraulic system.

The oil clutch system has a separate hydraulic pump
that has a flow control valve. See Figure 2 and Fig-
ure 3. The flow control valve is set at 25 to 26 liter/
min (6 to 7 gal/min) at 1100 kPa (160 psi) and 1755
rpm. The oil flows from the pump to the oil cooler in
the radiator. From the oil cooler the oil flows through
an oil filter. Oil from the outlet of the filter goes to
cool the oil clutch and to lubricate the pump drive ar-
rangement. To prevent damage to the oil cooler and
filter when the oil is cold, a bypass valve is installed
in the pump. The bypass valve opens when the pres-
sure reaches 1380 kPa (200 psi). When the bypass
valve opens, oil flows both to the sump and to the oil
cooler. A pressure switch is installed in the supply
line for the oil cooler. The switch energize a warning
light when the oil pressure decreases to 40 to 70 kPa
(6 to 10 psi).

1

Description

1200 SRM 334

1.

CLUTCH HOUSING

2.

FLYWHEEL

3.

PILOT BEARING

4.

CLUTCH DISC

5.

PRESSURE PLATE

6.

CLUTCH SHAFT

7.

RELEASE BEARING

8.

NOZZLE

9.

BEARING CARRIER

10. BEARING
11. SEAL
12. SNAP RING

Figure 1. Oil Clutch Parts

2

1200 SRM 334

Description

Figure 2. Hydraulic Schematic for Oil Clutch

System

Legend for Figure 2

1.

HYDRAULIC PUMP

2.

FLOW CONTROL VALVE

3.

BYPASS VALVE

4.

OIL COOLER

5.

PRESSURE SWITCH

6.

OIL FILTER

7.

CLUTCH HOUSING

8.

SUCTION SCREEN

9.

FLYWHEEL HOUSING

3

Description

1200 SRM 334

Figure 3. Hydraulic System for Oil Clutch

4

1200 SRM 334

Oil Clutch Assembly Repair

Legend for Figure 3

1.

HYDRAULIC PUMP

2.

SUCTION LINE

3.

FROM OIL COOLER

4.

TO OIL COOLER

5.

TO CLUTCH PARTS

6.

TO CHAIN DRIVE ARRANGEMENT

7.

BYPASS LINE

8.

OIL FILTER

Oil Clutch Assembly Repair

REMOVE AND DISASSEMBLE

WARNING

The clutch booster spring is under tension. Al-
ways remove the clutch booster spring before
disconnecting the clutch linkage.

NOTE:

The oil clutch assembly can be removed with

the engine and transmission installed.

1.

Remove the pedal bracket (see Figure 4) as fol-
lows:

a. Loosen the eyebolt for the clutch booster

spring. Remove the spring.

b. Disconnect and remove the clutch link to the

release crank.

c.

Disconnect the brake push rod at the brake
pedal. Remove the pedal return spring.

d. Remove the capscrews that hold the pedal

bracket to the transmission.

Remove the

pedal bracket assembly.

2.

Remove the suction line between the pump and
the clutch housing to drain the oil. Remove the
bypass line between the pump and the clutch
housing. Put caps on the fittings. See Figure 3.

3.

Disconnect the hydraulic lines from the oil cooler
at the pump and the oil filter. Put caps on the
open fittings. Remove the oil line that fits be-
tween the flywheel housing and the oil filter. See
Figure 3.

4.

Remove the oil pump from the clutch housing.
Remove the sleeve from the driven sprocket for
the pump drive.

5.

Remove the capscrews for the universal joints
at the transmission and the yoke on the clutch
shaft. Remove the yoke from the clutch shaft,
then remove the drive shaft. Remove the cap-
screws for the bearing carrier. Remove the bear-
ing carrier from the clutch housing.

1.

PEDAL BRACKET

2.

CLUTCH PEDAL

3.

CLUTCH
BOOSTER SPRING

4.

BRAKE PEDAL

Figure 4. Pedal Bracket

6.

Remove the capscrews that hold the clutch hous-
ing to the frame.

Connect a lifting device to

the clutch housing. (The clutch housing can be
removed from the top or the bottom of the lift
truck.) Put blocks under the flywheel housing to
hold the weight of the engine.

7.

Remove the capscrews that hold the clutch hous-
ing to the flywheel housing. The two capscrews
at the bottom are removed from the flywheel
housing.

8.

There are holes with threads in the clutch hous-
ing so the clutch housing can be separated from
the flywheel housing. Install capscrews in these
holes and separate the housings.

9.

Push on the bearing for the driven sprocket
through the hole for the pump and slowly re-
move the clutch housing from the lift truck.

5

Oil Clutch Assembly Repair

1200 SRM 334

10. Loosen each of the eight capscrews (2 to 3 turns

at a time) that hold the pressure plate assembly
to the flywheel, then remove the pressure plate.
Remove the clutch disc. See Figure 5.

1.

PRESSURE PLATE

2.

FLYWHEEL

Figure 5. Pressure Plate

CAUTION

The clutch disc can fall when the pressure plate
is removed.

11. Remove the release bearing and collar from the

yoke. Cut the lock wire and remove the setscrew
that holds the yoke to the release shaft. Slide the
release shaft from the clutch housing and yoke.
See Figure 8.

CLEAN AND INSPECT

1.

Clean all parts of the clutch with solvent. Make
sure the screen is free of metal particles.

2.

Inspect the bearings in the clutch housing and
bearing carrier for wear or damage. Do not try to
clean the release bearing.

3.

Inspect the clutch disc for holes in the lining.
Check for burnt lining that is black or hard.
Check for loose rivets or a bent plate. Check the
splines on the disc for wear or damage.

4.

Inspect the pressure plate for grooves or burned
areas. Look for cracks on the surface of the pres-
sure plate. Check for broken springs. Inspect the

pressure plate cover for cracks near the mounts
for the levers. Check the levers for wear or dam-
age.

5.

Inspect the splines of the clutch shaft for wear
or damage. Inspect the bearing surfaces of the
shaft for damage.

6.

Inspect the areas of the release shaft for wear
or damage. Make sure the bearing on the yoke
rotate freely.

7.

Inspect the flywheel for grooves and cracks that
are longer than 6.25 mm (0.25 in.). Look for areas
that have been too hot and have turned blue.

8.

Inspect the clutch pedal bearings for wear.

ASSEMBLE AND INSTALL

1.

Install the pilot bearing in the flywheel.

2.

Hold the correct side of the clutch disc against the
flywheel. See Figure 6. Put the pressure plate
assembly against the flywheel and disc. Start
several capscrews through the holes in the pres-
sure plate cover. Do not tighten the capscrews.

1.

THIS SIDE
TOWARD
TRANSMISSION

2.

FRICTION
MATERIAL

Figure 6. Clutch Disc

3.

Slide the clutch shaft through the splines of the
clutch disc into the pilot bearing in the flywheel.

6

1200 SRM 334

Oil Clutch Assembly Repair

Install the remainder of the capscrews. See Fig-
ure 7.

4.

Tighten the eight capscrews one turn at a time
until all the capscrews are tight. The torque on
the capscrews must be 20 N•m (15 lbf ft). Re-
move the clutch shaft.

1.

CLUTCH DISC

2.

PRESSURE PLATE

3.

CLUTCH SHAFT

Figure 7. Pressure Plate Installation

5.

Lubricate the bearings for the release shaft. In-
stall the release shaft and yoke in the housing.
Put the yoke in the correct position on the shaft
and tighten the lock screw. Install the lock wire
between the lock screw and the yoke. Install the
release bearing and collar and the spring on the
yoke. Make sure the nozzle for the clutch disc is
in the correct position. See Figure 8.

6.

Apply a sealant (Hyster Part No. 264159) on the
flange of the clutch housing. Install the clutch
housing to the flywheel housing. Install the cap-
screws and tighten them to 38 N•m (28 lbf ft).

7.

Install the bearing on the clutch shaft. Install
the bearing and shaft in the bearing carrier. In-
stall the snap ring for the bearing in the bearing
carrier. Install the seal in the bearing carrier. In-
stall the O-ring on the bearing carrier. See Fig-
ure 1.

8.

Install the bearing carrier and the clutch shaft in
the clutch housing. Make sure the clutch shaft
fits into the pilot bearing. Tighten the capscrews
for the bearing carrier to 38 N•m (28 lbf ft). In-
stall the yoke on the clutch shaft. See Figure 1.

9.

If removed, install the mount brackets on the
clutch housing. Tighten the capscrews for the
mount brackets to 165 N•m (122 lbf ft). Install
the capscrews, washers, and shims that hold the
clutch housing to the frame. Remove any blocks
from under the engine so the mount brackets are
on the mounts. Use a level on the frame of the lift
truck to make sure the frame is parallel with the
floor. Use a level on the yoke of the clutch shaft
to check that the yoke is vertical. Add or remove
shims from under the mount bracket so that the
yoke is within 0.5 to 1.5 mm (0.02 to 0.06 in.) of
true vertical. After adjustments, tighten the cap-
screws for the mounts to 40 N•m (30 lbf ft). See
Figure 10.

1.

RELEASE SHAFT

2.

YOKE

3.

SLEEVE BEARING

4.

LOCK SCREW AND
LOCK WIRE

5.

RELEASE
BEARING AND
COLLAR

6.

SPRING

7.

NOZZLE

Figure 8. Release Shaft and Bearing

7

Oil Clutch Assembly Repair

1200 SRM 334

10. Install the sleeve for the hydraulic pump in the

driven sprocket. See Figure 9. Make sure the
O-ring is on the flange of the hydraulic pump,
then install the pump on the clutch housing.

1.

SLEEVE

Figure 9. Sleeve for Hydraulic Pump

11. Install the oil lines between the clutch housing

and the hydraulic pump. Connect the oil lines
from the oil cooler to the oil filter and the hy-
draulic pump. Install the oil line between the
flywheel housing and the oil filter. Install the oil
line between the oil filter and the nozzle for the
clutch disc. See Figure 3.

12. Install the drive shaft and capscrews for the

universal joints.

A thread locking compound

(Hyster Part No. 264134) must be used on the
capscrews. Make sure the capscrews are thor-
oughly cleaned before using the thread locking
compound. Tighten the capscrews to 24 N•m
(18 lbf ft) using a cross pattern.

Tighten the

capscrews again using the same sequence.

13. Install the pedal bracket (see Figure 4) as follows:

a. Lubricate the bearings for the clutch pedal

with multipurpose grease. Install the pedal
and snap ring on the shaft.

b. Use a sealant (Hyster Part No. 264159) be-

tween the pedal bracket and the transmis-
sion. Install the bracket and tighten the cap-
screws to 38 N•m (28 lbf ft). Install the push
rod and return spring for the brake pedal. In-
stall the link between the release shaft and
the clutch pedal. Adjust the clutch pedal be-
fore installing the clutch booster spring. In-
stall the clutch booster spring and tighten
the nuts for the eyebolt completely.

14. Make sure the drain plug is tight. Fill the clutch

housing with the correct oil. Check the adjust-
ment of the clutch and brake pedals.

1.

CLUTCH HOUSING

2.

MOUNT BRACKET

3.

WASHER

4.

SHIM

5.

WASHER

6.

RUBBER MOUNT

7.

FRAME

Figure 10. Clutch Housing Mounts

8

1200 SRM 334

Bypass Valve Adjustment for Cold Oil

Clutch Pedal and Linkage Adjustment

1.

The height of the pedal must be 146 ±1.0 mm
(5.75 ±0.04 in.)

from the bottom of the pedal

pad to the top of the floor plate. Make sure the
booster spring pulls the pedal to the stop. Use the
pedal stop capscrew to adjust the height. Tighten
the jam nut. See Figure 11.

WARNING

The clutch booster spring is under tension. Al-
ways remove the clutch booster spring before
disconnecting the clutch linkage.

2.

Loosen the eyebolt completely and remove the
clutch booster spring. Adjust the rod end at the
crank until the release bearing touches the fin-
gers on the pressure plate. Rotate the rod end
counterclockwise one complete turn. Tighten the
jam nut for the rod end. Connect the rod end to
the crank using the spring washers and pin. In-
stall the booster spring and tighten the eyebolt
completely.

1.

CLUTCH PEDAL

2.

BOOSTER SPRING

3.

PEDAL STOP
CAPSCREW

4.

CLUTCH LINK

5.

CRANK FOR
RELEASE SHAFT

6.

ROD END

7.

EYEBOLT

Figure 11. Clutch Linkage Adjustment

Bypass Valve Adjustment for Cold Oil

1.

Remove the line to the oil cooler at the hydraulic
pump. See Figure 12. Put a cap on the fitting
at the line. Install a 0 to 2 MPa (0 to 300 psi)
gauge in the port of the hydraulic pump. The
oil temperature must be below 38 C (100 F) when
doing the pressure check.

2.

Disconnect the following to prevent the engine
from starting: (1) the wiring harness connector
at the distributor (GM engine) or (2) the wire
from the solenoid at the fuel injection pump
(Perkins engine). Turn the key to the START
position to rotate the engine and then read the
gauge.

3.

The gauge must read 1310 to 1450 kPa (190 to
210 psi) when the engine is turning. If the bypass

valve opens before 1310 kPa (190 psi) is reached,
shims must be added to the spring. If the gauge
indicates more than 1450 kPa (210 psi), shims
must be removed from the valve.

4.

Remove the plug for the bypass valve on the
bottom of the hydraulic pump.

Remove the

spring and the spool. Note the position of the
spool for reference during installation. Add or
remove shims from the plug. Removing 0.38 mm
(0.015 in.) shims lowers the pressure needed to
open the valve by 27.6 kPa (4 psi).

5.

Install the spool, spring, shims, and plug. Repeat
the pressure check to make sure the setting is
correct.

9

Troubleshooting

1200 SRM 334

Figure 12. Hydraulic Pump

Legend for Figure 12

1.

INLET

2.

OUTLET (TO OIL COOLER)

3.

OUTLET (TO CLUTCH HOUSING)

4.

BYPASS VALVE SPOOL

5.

SPRING

6.

SHIMS

7.

PLUG

Troubleshooting

PROBLEM

POSSIBLE CAUSE

PROCEDURE OR ACTION

The clutch does not engage
smoothly.

Loss of oil to the clutch.

Check for leaks and fill if required.

Release linkage is damaged or needs
adjustment.

Repair or adjust linkage.

Eyebolt for booster spring is not
tightened.

Tighten eyebolt for booster.

Adjustment of pedal is wrong.

Adjust pedal.

Friction surface of pressure plate is
damaged.

Repair or replace pressure plate.

Friction surface of flywheel is dam-
aged.

Repair or replace flywheel.

Springs in pressure plate are dam-
aged.

Replace springs.

Disc material is worn or damaged.

Replace disc material.

Clutch disc is bent.

Replace clutch disc.

Pressure plate levers are not ad-
justed correctly.

Adjust pressure plate levers.

Pressure plate levers are damaged.

Replace pressure plate levers.

Oil nozzle is damaged.

Replace oil nozzle.

10

1200 SRM 334

Troubleshooting

PROBLEM

POSSIBLE CAUSE

PROCEDURE OR ACTION

The clutch does not engage
smoothly. (Cont.)

Flywheel capscrews are loose.

Tighten flywheel capscrews.

The clutch does not hold.

Pedal does not return to stop.

Adjust pedal.

Clutch disc is worn.

Replace clutch disc.

Linkage is not adjusted correctly.

Adjust linkage.

Springs for pressure plate are dam-
aged.

Replace springs.

Pressure plate levers are damaged.

Replace pressure plate levers.

Friction surface of pressure plate is
damaged.

Repair or replace pressure plate.

Friction surface of flywheel is dam-
aged.

Repair or replace flywheel.

Loss of oil to the clutch.

Check for leaks and fill if required.

The

clutch

engages

sud-

denly.

Disc material is worn or damaged.

Replace disc.

Pressure plate levers do not operate
correctly.

Adjust pressure plate levers.

Splines on clutch disc are damaged.

Replace splines.

Loss of oil to the clutch.

Check for leaks and fill if required.

Clutch disc is installed wrong.

Re-install clutch disc.

Clutch release mechanism is dam-
aged.

Replace clutch release mechanism.

The clutch does not release.

Linkage is not adjusted correctly.

Adjust linkage.

Disc material is damaged.

Replace disc.

Release fork or shaft is damaged.

Replace release fork or shaft.

Splines on clutch disc are damaged.

Replace splines.

Splines on clutch shaft are damaged.

Replace splines.

Pilot bearing is damaged.

Replace pilot bearing.

11

Troubleshooting

1200 SRM 334

PROBLEM

POSSIBLE CAUSE

PROCEDURE OR ACTION

The clutch does not release.
(Cont.)

Pressure plate levers do not operate
correctly.

Adjust pressure plate levers.

Release fork is installed wrong.

Re-install release fork.

Noise when clutch pedal is
pushed.

Release bearing is damaged.

Replace release bearing.

Pilot bearing is damaged.

Replace pilot bearing.

Clutch disc is damaged.

Replace clutch disc.

Springs in pressure plate are dam-
aged.

Replace springs.

Pedal shaft needs lubrication.

Lubricate pedal shaft.

Flywheel capscrews are loose.

Tighten flywheel capscrews.

Crankshaft clearance is not correct.

Adjust crankshaft clearance.

Noise when clutch pedal is
not pushed.

Pilot bearing is damaged.

Replace pilot bearing.

Linkage is not adjusted correctly.

Adjust linkage.

Flywheel capscrews are loose.

Tighten flywheel capscrews.

Clutch pedal does not return
to stop.

Linkage is not adjusted correctly.

Adjust linkage.

Pedal shaft is damaged or needs lu-
brication.

Replace or lubricate pedal shaft.

Clutch linkage is damaged.

Replace linkage.

Pressure plate levers are damaged.

Replace pressure plate levers.

Release fork is installed wrong.

Re-install release fork.

Loss of oil to the clutch.

Check for leaks and fill if required.

12

TECHNICAL PUBLICATIONS

1200 SRM 334

11/97 (8/86) Printed in U.S.A.