Hyster W30-40ZA User manual

WALKIE HIGH LIFT
HYDRAULIC SYSTEM
W30-40ZA [B453];
W20-30ZR [B455];
W25-30-40ZC[B454]
PART NO. 1524251 2000 SRM 1025

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!

Walkie High Lift Hydraulic System Table of Contents
TABLE OF CONTENTS
General ............................................................................................................................................................... 1
Description of Operation.................................................................................................................................... 1
Hydraulic Oil ................................................................................................................................................. 2
Clean .............................................................................................................................................................. 2
Sound Level.................................................................................................................................................... 2
Special Precautions............................................................................................................................................ 2
Control Valve...................................................................................................................................................... 3
Hydraulic Reservoir........................................................................................................................................... 4
Description ..................................................................................................................................................... 4
Manual Lowering............................................................................................................................................... 4
Lift Pump and Motor Repair ............................................................................................................................. 6
General........................................................................................................................................................... 6
Remove Lift Pump and Motor Assembly...................................................................................................... 6
Disassemble ................................................................................................................................................... 11
Remove Reservoir...................................................................................................................................... 11
Remove Pump Motor................................................................................................................................. 11
Disassemble Pump .................................................................................................................................... 11
Assemble ........................................................................................................................................................ 12
Assemble Pump ......................................................................................................................................... 12
Install Pump Motor ................................................................................................................................... 12
Install Reservoir to Pump......................................................................................................................... 12
Install Lift Pump and Motor Assembly........................................................................................................ 12
Valve Repair ....................................................................................................................................................... 13
Proportional Valve (Lowering) ...................................................................................................................... 13
Remove....................................................................................................................................................... 13
Install......................................................................................................................................................... 13
Directional Valve ........................................................................................................................................... 14
Remove....................................................................................................................................................... 14
Install......................................................................................................................................................... 14
Lift Valve........................................................................................................................................................ 15
Remove....................................................................................................................................................... 15
Install......................................................................................................................................................... 15
Counterbalance Valve.................................................................................................................................... 16
W20/30ZR................................................................................................................................................... 16
Remove .................................................................................................................................................. 16
Install..................................................................................................................................................... 16
W25/30/40ZC ............................................................................................................................................. 17
Remove .................................................................................................................................................. 17
Install..................................................................................................................................................... 17
Relief Valve and Check Valve........................................................................................................................ 18
Remove....................................................................................................................................................... 18
Install......................................................................................................................................................... 18
Pilot Operated Check Valve .......................................................................................................................... 18
W20/30ZR................................................................................................................................................... 18
Remove .................................................................................................................................................. 19
Install..................................................................................................................................................... 19
Selector Valves: Reach, Tilt, and Sideshift .................................................................................................. 19
W20/30ZR and W25/30/40ZC.................................................................................................................... 19
Remove .................................................................................................................................................. 19
Install..................................................................................................................................................... 20
Relief Valve Adjustment .................................................................................................................................... 21
©2003 HYSTER COMPANY i

Table of Contents Walkie High Lift Hydraulic System
TABLE OF CONTENTS (Continued)
Bleed Hydraulic System .................................................................................................................................... 22
Troubleshooting.................................................................................................................................................. 22
Hydraulic Diagrams and Schematics ............................................................................................................... 25
This section is for the following models:
W30-40ZA [B453];
W20-30ZR [B455];
W25-30-40ZC [B454]
ii

2000 SRM 1025 Description of Operation
General
This section covers the troubleshooting and repair
procedures for the hydraulic components on the W30/
40ZA, W25/30/40ZC, and W20/30ZR lift trucks.
It also includes the remove and install procedures
for the solenoid coils used to activate the hydraulic
valves.
For troubleshooting and repairs of the electrical com-
ponents, see Electrical System 2200 SRM 1026 and
ZAPITM Controllers 2200 SRM 1064.
Description of Operation
The hydraulic system of the W30/40ZA, W25/30/
40ZC, and W20/30ZR lift trucks includes:
•Reservoir
•Pump
•Check valve
•Relief valve
•Proportional lowering valve
•Lift cylinder(s)
•Connecting hoses and tubes
Based on the model and configuration of the hy-
draulic system, it can also include:
•Lift valve
•Directional valve(s)
•Selector valve(s)
•Counterbalance valve
•Pilot operated check valve
•Sideshift cylinder
•Tilt cylinders
•Reach cylinders
•Auxiliary cylinder(s)
The reservoir contains the hydraulic fluid necessary
for the operation of the system. It acts as a heat sink
to provide cooling. As the hydraulic oil leaves the
reservoir, it is filtered through an internal strainer
in the reservoir.
The hydraulic pump provides the flow of the hy-
draulic oil. It moves the oil to activate the cylinders.
A check valve provides flow of the hydraulic oil in one
direction only. In this hydraulic system, it prevents
the oil from flowing backwards through the pump.
A relief valve limits maximum pressure to protect the
hydraulic system components.
The proportional lowering valve is a normally closed
valve. When it opens, hydraulic oil from the lift cylin-
ders is allowed to return to the reservoir and the
forks lower. Rate of flow is regulated by how far the
valve opens.
The lift cylinder(s) rod extends to raise the forks
through a series of mast channels and chains.
The connecting hoses and tubing connect the various
hydraulic components in the lift truck to complete
the hydraulic circuit.
The lift valve is used on systems that have more than
a lift/lower function. It is a normally closed valve
which opens during the lift function. During other
functions, such as sideshift, it remains closed to pre-
vent flow to the lift cylinders.
The directional valve(s) is a three position normally
closed valve located on the pump. In its normal posi-
tion, it blocks the flow of oil to a double acting cylin-
der, such as a sideshift cylinder. Activated in one po-
sition, it provides flow to extend a cylinder rod. Acti-
vated in the opposite position, it reverses flow to the
cylinder to retract the cylinder rod.
The selector valve(s) is a normally closed valve lo-
cated on the mast. Selector valves are used to direct
the flow from a single pair of hydraulic lines to mul-
tiple double acting hydraulic cylinders.
The counterbalance valve provides free flow in one
direction and resistance to flow in the opposite direc-
tion. It is located in the tilt circuit to control forward
tilt.
The pilot operated check valve is located in the re-
tract circuit and is activated by an auxiliary pres-
sure. Its function is to maintain pressure on the rod
side of the piston to hold the reach mechanism in the
retract position.
The tilt cylinders rods extend to tilt the forks forward
away from the lift truck. The rods retract to tilt the
forks back toward the lift truck.
The reach cylinders rods extend to move the forks
away from the lift truck. The rods retract to move
the forks back toward the lift truck.
1

Special Precautions 2000 SRM 1025
The function of the auxiliary cylinder(s) varies based
on the optional attachment.
HYDRAULIC OIL
The hydraulic oil in the system performs the dual
function of power transmission and lubrication. Us-
ing the correct fluid is essential to proper system
operation. See Periodic Maintenance 8000 SRM
1027 for the recommended hydraulic oil.
The level in the reservoir should be checked first
when troubleshooting lifting problems. Low oil lev-
els may make it appear that a problem exists with
the battery or hydraulic system.
CLEAN
Adhere to the following precautionary steps to be
sure that the hydraulic system remains clean.
1. Clean the reservoir and pump area to prevent
contaminants from entering the hydraulic sys-
tem.
2. Clean (flush) the entire system when a failure
is encountered to make sure all contaminants,
debris, and foreign objects are removed.
3. Filter each change of oil to prevent the introduc-
tion of contaminants into the system.
4. Provide continuous protection from airborne con-
tamination by keeping the breather cap clean
and serviceable.
SOUND LEVEL
Hydraulic system noise may be caused by both im-
properly selected oil and loose or damaged system
components.
• Cavitation - Can be caused by high fluid viscos-
ity, cold fluid temperatures, or a restriction in the
inlet screen or inlet tubing. At startup, low temper-
atures can cause pump noises due to cavitation.
• Aerated hydraulic oil - Results in system noise
that is similar to cavitation. Aerated oil is caused
by the ingestion of air through the pipe joints of
the inlet lines and high-velocity discharge lines, as
well as cylinder rod packing. Aeration can also
be caused by oil discharging above the fluid level
in the hydraulic reservoir. Air does not have suf-
ficienttimetoescapefromthefluidwhileinthe
reservoir before recycling through the system.
Special Precautions
WARNING
The capacitor in the transistor controller can
hold and electrical charge after the battery is
disconnected. To prevent an electrical shock
and personal injury, discharge the capacitor
before inspecting or repairing any component
in the drive unit compartment. Wear safety
glasses. Make certain that the battery has
been disconnected.
CAUTION
To avoid controller damage, always disconnect
the battery, discharge the capacitor, and never
put power to the controller while any power
wires are disconnected. Never short any con-
troller terminal or motor terminal to the bat-
tery. Make sure to use proper procedure when
servicing the controller.
1. Verify that the key switch is in the OFF position
and the battery connector is completely discon-
nected.
2. Discharge the capacitors in the controllers by
connecting a 200-ohm, 2-watt resistor across
the controller’s B+ and B terminals. DO NOT
short across the motor controller terminals
with a screwdriver or jumper wire. Remove the
200-ohm, 2-watt resistor before reconnecting the
battery. SeeFigure1.
2

2000 SRM 1025 Control Valve
Figure 1. Discharging the Capacitor
Legend for Figure 1
1. NEGATIVE CONNECTION
2. POSITIVE CONNECTION
3. 200-OHM, 2-WATT RESISTOR
4. INSULATED JUMPERWIRES
Control Valve
CAUTION
The hydraulic oil must be kept clean to prevent
damage to the control valve.
The control valve is part of the lift pump and mo-
tor assembly and is replaceable but not adjustable.
When the operator selects a hydraulic function by
pressing a button on the control handle, a signal is
sent to the traction/lift controller, is processed, and
is sent to the pump assembly. Lifting speed is con-
trolled by varying the pump motor speed. Lower-
ing speed is controlled by a proportional electro-hy-
draulic valve on the pump assembly.
The control valve is designed with close tolerances
and must be kept clean to work properly.
3

Manual Lowering 2000 SRM 1025
Hydraulic Reservoir
DESCRIPTION
The hydraulic reservoir is made of a durable,
translucent plastic that allows the operator to see
how much hydraulic oil is in the reservoir. The
reservoir is clamped to the adapter plate on the
bottom of the pump and motor assembly in the drive
unit compartment or hydraulic unit compartment.
The reservoir has either a graduated scale or MIN
and MAX marks on the side depending on model
and should only be filled with hydraulic oil to the
graduated scale or MIN mark.SeeTable1.There
isafillcaplocatedonthetopofthereservoiranda
drain plug and O-ring located at the bottom on one
side of the reservoir.
Table 1. Hydraulic Reservoir
Model Description Reservoir Markings Hydraulic Oil
Quantity
W25/30/40ZC Counterbalance MIN/MAX 11.5 liter (12.2 qt)
W30/40ZA Straddle Stacker Graduated Scale 11 liter (11.6 qt)
W20/30ZR Reach Carriage Graduated Scale 11 liter (11.6 qt)
Manual Lowering
WARNING
Always verify that no one is under or near
the lift mechanism or load during the manual
lowering procedure. Verify that there are no
obstructions beneath the lift mechanism or
load. If the mast does not lower when the man-
ual lowering valve is activated, deactivate the
valve immediately and determine the cause.
WARNING
Failure to return the manual lowering screw to
the full clockwise position will cause the forks
to lower unexpectedly.
A provision is provided on the lowering valve to
allow manual lowering of the forks if necessary.
Manual lowering is accomplished by turning the
manual override screw counterclockwise with a
7-mm wrench. In this position, the valve will remain
open.
Loosen the manual override screw SLOWLY until
theforksbegintolower.Besuretoreturnthescrew
to the original position once the manual lowering
process is complete by slowly turning the screw until
it stops. Torque the manual override screw to 4.0
N•m (36 lbf in).
On the W30-40ZA models without sideshift, the man-
ual override screw is located on the back of the low-
ering solenoid near the mounting wall. See Figure 2.
On all other trucks with auxiliary functions, the
manual override screw is located under the lowering
solenoid block above the hydraulic reservoir. See
Figure 3.
4

2000 SRM 1025 Manual Lowering
Figure 2. Single Function - Manual Lowering Screw (Top View)
5

Lift Pump and Motor Repair 2000 SRM 1025
Figure 3. Auxiliary Function - Manual Lowering Screw (Side View)
Lift Pump and Motor Repair
GENERAL
The hydraulic pump and motor assembly has differ-
ent parts working together to perform the functions
of the hydraulic system. The pump is not repairable
and must be replaced when it is not functioning prop-
erly. When replacement of the pump is necessary,
the entire hydraulic pump and motor assembly and
the hydraulic reservoir must be removed and disas-
sembled. Some components may be replaced without
totally disassembling the hydraulic pump and mo-
tor assembly. An electric motor drives the hydraulic
pump. It may be removed without removing the en-
tire assembly from the drive unit compartment or hy-
draulic unit compartment. Do only the steps neces-
sary to perform the repairs needed.
The lift pump and motor are connected by capscrews
and are located on top of the hydraulic reservoir in-
side the drive unit compartment or hydraulic unit
compartment.
NOTE: It is not necessary to remove the complete
lift pump and motor assembly to remove the pump
motor. When removing only the pump motor, see Re-
move Pump Motor.
REMOVE LIFT PUMP AND MOTOR
ASSEMBLY
1. Move the lift truck to a safe and level area.
2. Lower the forks completely to relieve pressure
from the hydraulic system.
6

2000 SRM 1025 Lift Pump and Motor Repair
3. Turn key switch to OFF position and disconnect
battery.
4. Block load wheels to prevent lift truck from mov-
ing. Refer to Periodic Maintenance 8000 SRM
1027.
5. Remove drive unit compartment cover. On W25/
30/40ZC lift trucks, also remove the hydraulic
compartment cover.
6. Discharge the capacitor. See Special Precau-
tions.
For the following procedures, refer to Figure 5 for
W30/40ZA lift trucks, Figure 6 for W20/30ZR lift
trucks, and Figure 7 for W25/30/40ZC lift trucks.
7. Tag, identify, and disconnect the power wires to
the lift pump motor.
8. Tag and identify the control wiring plugs and
valve coils.
9. Remove the locking screws from the control
wiring plugs. Disconnect the plugs from the
coils.
WARNING
Hydraulic oil hoses and lines may be under
high pressure. Hydraulic oil can be injected
into the body by pressure. To prevent possible
injury, shield yourself from any escaping oil.
Wrap a rag around the fitting and loosen the
fitting and loosen the connection slowly.
CAUTION
To prevent dirt or contaminants from entering
the hydraulic system, always install caps on
the hoses and ports of the pump.
10. Tag, identify, and disconnect the hydraulic hoses.
11. The lift pump is attached to the frame with a
bracket and vibration isolators. Remove the
two nuts and washers attaching the mounting
bracket to the isolators. See Figure 4.
12. Tilt the top of the lift pump and motor assembly
away from the frame and lift up to remove.
13. Place hydraulic pump and motor assembly on the
floor securely supported in an upright position.
The reservoir is unstable in an upright position
and must be securely supported at all times.
1. LIFT PUMP AND MOTOR ASSEMBLY
2. CAPSCREW
3. LOCKWASHER
4. PUMP MOUNTING BRACKET
5. NUT
6. WASHER
7. RUBBER ISOLATOR
8. COUNTERSUNK CAPSCREW
Figure 4. Lift Pump and Motor Assembly
7

Lift Pump and Motor Repair 2000 SRM 1025
1. MOTOR
2. COUPLING
3. HYDRAULIC RESERVOIR
4. CLAMP
5. DRAIN PLUG AND O-RING
6. BREATHER/FILLER CAP
7. VALVE BLOCK
8. PROPORTIONAL VALVE (LOWERING)
9. PUMP
10. TUBE
11. PRESSURE RELIEF VALVE
12. CHECK VALVE
13. SCREW
14. RESERVOIR MOUNTING BRACKET
15. SCREWS
16. SCREWS
17. CAPSCREWS
Figure 5. Lift Pump and Motor Assembly-Without Auxiliary (W30/40ZA)
8

2000 SRM 1025 Lift Pump and Motor Repair
1. MOTOR
2. COUPLING
3. PUMP HOUSING
4. HYDRAULIC RESERVOIR
5. CLAMP
6. DRAIN PLUG AND O-RING
7. MAIN VALVE BLOCK
8. PLUG
9. PROPORTIONAL VALVE (LOWERING)
10. LIFT VALVE AND COIL
11. CAPSCREWS
12. BREATHER/FILLER CAP
13. SCREW
14. AUXILIARY VALVE BLOCK
15. DIRECTIONAL VALVE
16. TUBES
17. PRESSURE RELIEF VALVE
18. CHECK VALVE
19. SCREW
20. ADAPTOR PLATE
21. SCREW
Figure 6. Lift Pump and Motor Assembly With Auxiliary (W20/30ZR)
9

Lift Pump and Motor Repair 2000 SRM 1025
1. MOTOR
2. COUPLING
3. PUMP HOUSING
4. HYDRAULIC RESERVOIR
5. SCREW
6. DRAIN PLUG AND O-RING
7. CLAMPS AND O-RING
8. MAIN VALVE BLOCK
9. PROPORTIONAL VALVE (LOWERING)
10. LIFT VALVE AND COIL
11. BREATHER/FILLER CAP AND ELBOW
12. SCREW
13. PLUG
14. AUXILIARY VALVE BLOCK
15. VALVE (TILT)
16. VALVE (SIDESHIFT)
17. TUBE
18. PRESSURE RELIEF VALVE
19. CHECK VALVE
20. CAPSCREWS
Figure 7. Lift Pump and Motor Assembly With Auxiliary (W25/30/40ZC)
10

2000 SRM 1025 Lift Pump and Motor Repair
DISASSEMBLE
Remove Reservoir
For the following procedures, refer to Figure 5 for
W30/40ZA lift trucks, Figure 6 for W20/30ZR lift
trucks, and Figure 7 for W25/30/40ZC lift trucks.
1. Use the following procedure that applies to your
lift truck:
a. Remove the screw from the clamp and re-
move the clamp from the reservoir and adap-
tor.
b. Remove the four capscrews from the clamps
and remove the clamps from the reservoir
and the adaptor.
2. Lift the hydraulic pump and motor assembly
from the reservoir.
3. Place pump and motor assembly on a clean drip
pan in a horizontal position.
4. Remove and inspect the O-ring seal located
between the hydraulic pump assembly and the
reservoir. Verify that the O-ring seal is not dam-
aged. Replace as needed.
5. Inspect the inlet strainer. If necessary, remove
the retaining clip to access the screen. Replace
parts that cannot be cleaned or are damaged.
CAUTION
Disposal of lubricants and fluids must meet lo-
cal environmental regulations.
6. Pour oil from reservoir into a container suitable
for disposal.
CAUTION
If oil is contaminated or excessively dirty, the
entire hydraulic system should be thoroughly
cleaned.
7. Examine the hydraulic reservoir. Inspect hy-
draulic reservoir for dirt, foreign materials, or
contamination. Clean and flush the hydraulic
reservoir as necessary.
Remove Pump Motor
1. If the lift pump and motor assembly has not been
previously removed, perform steps 1 through 6 in
Remove Lift Pump and Motor Assembly.
2. Tag and disconnect the power wires from the lift
pump motor.
3. Remove the two nuts and washers attaching the
lift pump mounting bracket to the rubber vibra-
tion isolators.
4. Tilt the lift pump and motor assembly forward,
away from the frame to gain access to the two
capscrews on the top of the lift pump motor.
5. Remove two capscrews from top of motor.
6. Lift the motor from the pump assembly.
7. Inspect the motor output shaft, the pump input
shaft, and the coupling. Replace worn or dam-
aged parts.
Disassemble Pump
For the following procedures, refer to Figure 5 for
W30/40ZA lift trucks, Figure 6 for W20/30ZR lift
trucks, and Figure 7 for W25/30/40ZC lift trucks.
1. Remove the two capscrews and lockwashers that
hold pump mounting bracket to pump and re-
move bracket. See Figure 4.
2. Separate reservoir adaptor plate from pump by
removing attaching hardware (W20/30ZR and
W30/40ZA only).
3. Tag and identify each tube and their correspond-
ing locations.
4. Remove tubes and associated items from bottom
of pump.
5. Use the following procedure that applies to your
lift truck:
a. Remove four screws retaining auxiliary valve
block to pump.
b. Remove four screws retaining valve block to
pump.
c. Remove the two fasteners retaining the main
valve block to the pump.
11

Lift Pump and Motor Repair 2000 SRM 1025
6. Remove relief valve and check valve from pump.
See Relief Valve and Check Valve, Remove.
7. Remove the coupling.
8. Use the following procedure that applies to your
lift truck:
a. Remove main valve block from pump hous-
ing.
b. Remove plugs from auxiliary ports.
ASSEMBLE
Assemble Pump
For the following procedures, refer to Figure 5 for
W30/40ZA lift trucks, Figure 6 for W20/30ZR lift
trucks, and Figure 7 for W25/30/40ZC lift trucks.
1. Position pump mounting bracket to pump and
install two capscrews and lockwashers to secure.
Torque the capscrews to 20 N•m (15 lbf ft). See
Figure 4.
2. Install tubes and related items to bottom of pump
as removed.
3. Secure reservoir adaptor plate to pump by in-
stalling attaching hardware.
4. Use the following procedure that applies to your
lift truck:
a. Install auxiliary valve block to pump using
fourscrewsandtorqueto22N•m(16lbfft).
b. Install valve block to pump using four screws
and torque to 22 N•m (16 lbf ft).
c. Install the main valve block to the pump
using two fasteners and torque to 22 N•m
(16 lbf ft).
5. Install the relief valve and check valve. See Re-
lief Valve and Check Valve, Install.
6. Use the following procedure that applies to your
lift truck:
a. Install main valve block to pump housing and
torque the capscrews to 22 N•m (16 lbf ft).
b. Install plugs into auxiliary ports in pump
housing and torque to 22 N•m (16 lbf ft).
Install Pump Motor
1. Lubricate the motor output shaft and the pump
input shaft with a light coating of multi - purpose
#2 grease with 2% to 4% molybdenum disulfide.
2. Install the coupling on the pump shaft.
3. Align the slot in the motor shaft with the cou-
pling. Lower the motor onto the pump, rotating
the body as necessary to engage the coupling and
then align the capscrews.
4. Tighten the capscrews to 8 N•m (71 lbf in).
Install Reservoir to Pump
1. Place reservoir in an upright position on the floor.
NOTE: The reservoir may be filled at this point or it
may be filled after the lift pump and motor assembly
has been installed.
2. Fill reservoir with hydraulic oil to proper level.
See Table 1.
3. Install the O-ring seal on the pump assembly. If
necessary, use a small amount of grease to hold
the O-ring seal in position.
4. Position the lift pump and motor assembly onto
the reservoir.
5. Use the following procedure that applies to the
hydraulic reservoir for your lift truck:
a. Install the clamp to the reservoir and adaptor
using the screw to tighten.
b. Install the clamps to the reservoir and the
adaptor and install the four capscrews to se-
cure the clamps.
INSTALL LIFT PUMP AND MOTOR
ASSEMBLY
1. Install hydraulic lift pump and motor assembly
in the lift truck and secure with the two nuts and
washers. Torque the nuts to 15 N•m (11 lbf ft).
2. Connect the control wiring plugs to the coils as
noted on tags.
3. Install the locking screws into the coil plugs.
4. Install the hydraulic hoses to the lift pump and
motor assembly as noted on tags.
12

2000 SRM 1025 Valve Repair
5. Connect the power wires to the lift pump motor
with the two nuts and washers. Torque the nuts
to 4.0 N•m (35 lbf in).
6. Fill reservoir with hydraulic oil to proper level.
SeeTable1.
7. Connect battery and turn key switch to ON posi-
tion.
8. Operate each hydraulic function several times to
purge the air from the hydraulic circuit.
9. Check the top of the lift cylinder to determine if
a buttonhead bleed screw is present. If a bleed
screw is present, bleed the air from the hydraulic
system. See Bleed Hydraulic System.
10. Check hydraulic oil level in reservoir and fill to
proper level. See Table 1.
11. Test lift truck by lifting and lowering a load sev-
eral times. Check for leaks.
12. Install the drive unit compartment cover. If nec-
essary, install the hydraulic unit compartment
cover.
Valve Repair
PROPORTIONAL VALVE (LOWERING)
Remove
1. Move lift truck to a safe and level area.
2. Lower the forks completely to relieve pressure
from the hydraulic system.
3. Turn key switch to OFF position and disconnect
battery.
4. Block load wheels to prevent lift truck from mov-
ing. Refer to Periodic Maintenance 8000 SRM
1027.
5. Remove the drive unit compartment cover. On
W25/30/40ZC lift trucks, also remove the hy-
draulic compartment cover.
6. Discharge the capacitor. See Special Precau-
tions.
WARNING
Hydraulic oil hoses and lines may be under
high pressure. Hydraulic oil can be injected
into the body by pressure. To prevent possible
injury, shield yourself from any escaping oil.
Wrap a rag around the fitting and loosen the
fitting and loosen the connection slowly.
CAUTION
To prevent dirt or contaminants from entering
the hydraulic system, always install caps on
the hoses and ports of the pump.
7. Tag and disconnect any power wires or hydraulic
hoses blocking access to the valve.
8. Remove the locking screw from the control wiring
plug. Disconnect the plug from the coil.
9. Remove the retaining clip and washer.
10. Slidethecoiloffofthevalve.
11. Remove the valve cartridge.
Install
1. Verify that the O-rings on the valve cartridge are
not damaged. Replace as needed.
2. Verify that the valve cartridge and valve block
are clean and not damaged.
3. Lubricate the valve cartridge threads and
O-rings with clean hydraulic oil.
4. Install the valve cartridge and torque to 27 N•m
(20 lbf ft).
5. Slide the coil onto the valve cartridge with the
lettering out towards the coil retainer.
6. Install the washer and retaining clip.
7. Connect any power wires and hydraulic hoses
previously disconnected.
8. Connect the control wiring plug to the coil.
9. Install the locking screw into the coil plug.
10. Connect battery and turn key switch to ON posi-
tion.
13

Valve Repair 2000 SRM 1025
11. Operate each hydraulic function several times to
purge the air from the hydraulic circuit.
12. Check the top of the lift cylinder to determine if
a buttonhead bleed screw is present. If a bleed
screw is present, bleed the air from the hydraulic
system. See Bleed Hydraulic System.
13. Check hydraulic oil level in reservoir and fill to
proper level. See Table 1.
14. Test the lift truck by lifting and lowering a load
several times. Check for leaks.
15. Install the drive unit compartment cover. If nec-
essary, install the hydraulic unit compartment
cover.
DIRECTIONAL VALVE
Remove
1. Move lift truck to a safe and level area.
2. Lower the forks completely to relieve pressure
from the hydraulic system.
3. Turn key switch to OFF position and disconnect
battery.
4. Block load wheels to prevent lift truck from mov-
ing. Refer to Periodic Maintenance 8000 SRM
1027.
5. Remove the drive unit compartment cover. On
W25/30/40ZC lift trucks, also remove the hy-
draulic compartment cover.
6. Discharge the capacitor. See Special Precau-
tions.
WARNING
Hydraulic oil hoses and lines may be under
high pressure. Hydraulic oil can be injected
into the body by pressure. To prevent possible
injury, shield yourself from any escaping oil.
Wrap a rag around the fitting and loosen the
fitting and loosen the connection slowly.
CAUTION
To prevent dirt or contaminants from entering
the hydraulic system, always install caps on
the hoses and ports of the pump.
7. Tag and disconnect any power wires or hydraulic
hoses blocking access to the valve.
8. Tag and identify the control wiring plugs and
valve coils.
9. Remove the locking screws from the control
wiring plugs. Disconnect the plugs from the
coils.
10. Remove the nut and slide the front coil off the
valve.
11. Removethespacerandtherearcoil.
12. Remove the valve cartridge.
Install
1. Verify that the O-rings on the valve cartridge are
not damaged. Replace as needed.
2. Verify that the valve cartridge and valve block
are clean and not damaged.
3. Lubricate the valve cartridge threads and
O-rings with clean hydraulic oil.
4. Installthevalvecartridgeandtorqueto34N•m
(25 lbf ft).
5. Slide the rear coil onto the valve cartridge with
the lettering out towards the front coil.
6. Slide the spacer and then the front coil onto the
valve cartridge with the lettering out towards the
coil retainer.
7. Install the nut and torque to 7 N•m (60 lbf in).
8. Connect the control wiring plugs to the coils as
noted on the tags.
9. Install the locking screws into the coil plugs.
10. Connect any power wires and hydraulic hoses
previously disconnected.
11. Connect battery and turn key switch to ON posi-
tion.
12. Operate each hydraulic function several times to
purge the air from the hydraulic circuit.
13. Check the top of the lift cylinder to determine if
a buttonhead bleed screw is present. If a bleed
screw is present, bleed the air from the hydraulic
system. See Bleed Hydraulic System.
14. Check hydraulic oil level in reservoir and fill to
proper level. See Table 1.
14

2000 SRM 1025 Valve Repair
15. Test lift truck by lifting and lowering a load sev-
eral times. Check for leaks.
16. Install the drive unit compartment cover. If nec-
essary, install the hydraulic unit compartment
cover.
LIFT VALVE
Remove
1. Move lift truck to a safe and level area.
2. Lower the forks completely to relieve pressure
from the hydraulic system.
3. Turn key switch to OFF position and disconnect
battery.
4. Block load wheels to prevent lift truck from mov-
ing. Refer to Periodic Maintenance 8000 SRM
1027.
5. Remove the drive unit compartment cover. On
W25/30/40ZC lift trucks, also remove the hy-
draulic compartment cover.
6. Discharge the capacitor. See Special Precau-
tions.
WARNING
Hydraulic oil hoses and lines may be under
high pressure. Hydraulic oil can be injected
into the bodybypressure.Topreventpossible
injury, shield yourself from any escaping oil.
Wrap a rag around the fitting and loosen the
fitting and loosen the connection slowly.
CAUTION
To prevent dirt or contaminants from entering
the hydraulic system, always install caps on
the hoses and ports of the pump.
7. Tag and disconnect any power wires or hydraulic
hoses blocking access to the valve.
8. Remove the locking screw from the control wiring
plug. Disconnect the plug from the coil.
9. Remove the nut from the top of the coil.
10. Remove the upper O-ring and slide the coil off the
valve cartridge.
11. Remove the lower O-ring from the valve car-
tridge.
12. Remove the valve cartridge.
Install
1. Verify that the valve cartridge and coil O-rings
are not damaged. Replace as needed.
2. Verify that the valve cartridge and valve block
are clean and not damaged.
3. Lubricate the valve cartridge threads and
O-rings with clean hydraulic oil.
4. Install the valve cartridge and torque to 27 N•m
(20 lbf ft).
5. Install the lower O-ring over the valve cartridge.
6. Slide the coil over the valve cartridge with the
lettering out towards the coil retainer.
7. Install the second O-ring over the valve car-
tridge.
8. Install the nut and torque to 7 N•m (60 lbf in).
9. Connect the control wiring plug to the coils.
10. Install the locking screw into the coil plug.
11. Connect any power wires and hydraulic hoses
previously disconnected.
12. Connect battery and turn key switch to ON posi-
tion.
13. Operate each hydraulic function several times to
purge the air from the hydraulic circuit.
14. Check the top of the lift cylinder to determine if
a buttonhead bleed screw is present. If a bleed
screw is present, bleed the air from the hydraulic
system. See Bleed Hydraulic System.
15. Check hydraulic oil level in reservoir and fill to
proper level. See Table 1.
16. Test lift truck by lifting and lowering a load sev-
eral times. Check for leaks.
17. Install the drive unit compartment cover. If nec-
essary, install the hydraulic unit compartment
cover.
15

Valve Repair 2000 SRM 1025
COUNTERBALANCE VALVE
W20/30ZR
Remove
1. Move the lift truck to a safe and level area.
2. Lower the forks completely and extend the forks
completely. Tilt the forks down until they contact
the floor.
3. Turn key switch to OFF position and disconnect
battery.
4. Block load wheels to prevent lift truck from mov-
ing. Refer to Periodic Maintenance 8000 SRM
1027.
5. Remove drive unit compartment cover.
6. Discharge the capacitor. See Special Precau-
tions.
WARNING
There are pinch points on the reach carriage
that can cause an injury. Use clamps and
blocks to stop the scissor arms from moving.
7. Install clamps and blocks (on both sides) be-
tween the load bearings and the bottom of the
rear frame of the reach assembly to keep the
forks from retracting. See Figure 8.
WARNING
Hydraulic oil hoses and lines may be under
high pressure. Hydraulic oil can be injected
into the body by pressure. To prevent possible
injury, shield yourself from any escaping oil.
Wrap a rag around the fitting and loosen the
fitting and loosen the connection slowly.
8. Loosen both hydraulic hose fittings on the bottom
of the valve block to relieve pressure from the tilt
circuit. See Figure 9.
9. Remove the valve cartridge.
Install
1. Verify that the O-rings on the valve cartridge are
not damaged. Replace as needed.
2. Verify that the valve cartridge and valve block
are clean and not damaged.
1. REAR FRAME OF THE REACH ASSEMBLY
2. LOAD BEARING
3. WOOD BLOCK
4. CLAMP
Figure 8. Typical Blocks and Clamps
Installation
3. Lubricate the valve cartridge threads and
O-rings with clean hydraulic oil.
4. Installthevalvecartridgeandtorqueto47N•m
(35 lbf ft).
5. Tighten the hydraulic hose fittings.
6. Remove the clamps and blocks.
7. Connect battery and turn key switch to ON posi-
tion.
8. Operate each hydraulic function several times to
purge the air from the hydraulic circuit.
9. Check hydraulic oil level in reservoir and fill to
proper level. See Table 1.
10. Test lift truck by lifting and lowering a load sev-
eral times. Check for leaks.
11. Install the drive unit compartment cover.
16