Hoist Valve - Komatsu 830E Shop Manual

HOIST VALVE

Relieve pressure before disconnecting hydraulic
lines. Tighten all connections securely before
applying pressure.
Hydraulic fluid escaping under pressure can
have sufficient force to enter a person's body by
penetrating the skin and cause serious injury and
possibly death if proper medical treatment by a
physician familiar with this type of injury is not
received immediately.
FIGURE 8-1. HOIST VALVE INSTALLATION
1. Hoist Pilot Valve Supply
2. Power Up Line
3. Inlet From Filters
4. Return To Tank
L08031
HOIST CIRCUIT COMPONENT REPAIR
5. Power Down Line
6. To Hoist Pilot Valve
7. Return To Tank
8. Separator Plate
Hoist Circuit Component Repair
Removal
1. Shut down engine and turn keyswitch "Off".
2. Thoroughly clean the exterior of the hoist valve.
3. Disconnect and cap or plug all line connections
to help prevent hydraulic oil contamination,
refer to Figure 8-1.
4. Remove capscrews and lockwashers securing
the hoist valve to its mounting bracket.
The hoist valve weighs approximately 320 lbs.
(145 Kg). Use a suitable lifting device that can
handle the load safely.
5. Attach a suitable lifting device (that can handle
the load safely) to the hoist valve and remove
hoist valve from truck.
6. Move the hoist valve to a clean work area for
disassembly.
Installation
1. Attach a suitable lifting device to the hoist valve.
Move the hoist valve into position with the sep-
arator plate (8, Figure 8-1) located to the rear.
Secure in place with capscrews, nuts and lock-
washers. Tighten
torque.
Note: Be certain hoist valve assembly is positioned
with separator plate (8, Figure 8-1) towards rear of
truck when valve is lowered onto mounting plate.
2. Using new O-rings at the flange fittings, connect
hydraulic lines. Tighten flange capscrews to
standard torque. Refer to Figure 8-1 for hydrau-
lic line location.
3. Connect pilot supply lines, tighten fittings
securely.
4. Start the engine. Raise and lower body to check
for proper operation. Observe for leaks.
5. Service hydraulic tank if necessary.
capscrews to standard
L8-1