Hyster W20-30ZR, Manual

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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 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 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