Komatsu 830E-AC Shop Manual page 746

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.
FIGURE 8-2. HOIST VALVE ASSEMBLY
1. Inlet Section
2. Spool Section Cover
3. Spool Section
4. Inlet Section
O-Ring Replacement
NOTE: It is not necessary to remove the individual
valve sections to accomplish
emergency field repair is required to replace the O-
rings between sections
Loosening and retightening of the main valve tie rod
nut could cause distortion resulting in binding or
severely sticking plungers, poppet and spools.
L8-4
5. Tube
6. Tie Rods
7. Nuts and Washers
8. Inlet Section Cover
repair, unless
to prevent leakage.
Hoist Circuit Component Repair
To replace the O-rings between the valve sections:
1. Match mark each part on the hoist valve to aid
in reassembly. Remove the four tie rod nuts
from one end of the valve. Slide the tie rods
from the valve and separate the sections.
2. Inspect the machined sealing surfaces for
scratches or nicks. If scratches or nicks are
found, remove by lapping on a smooth flat steel
surface with fine lapping compound.
3. Lubricate the new O-rings lightly with multipur-
pose grease. Replace O-rings between sec-
tions. Stack the sections together making sure
O-rings between the sections are properly posi-
tioned.
4. Install the four tie rods with the dished washer
between the nut and housing (Figure 8-3).
FIGURE 8-3. TIE ROD INSTALLATION
5. A torque wrench should be used to tighten the
nuts in the pattern as shown in Figure 8-4. The
tie rods should be tightened evenly to 217 N·m
(160 ft lbs) torque in the following sequence.
a. Tighten nuts evenly to 27 N·m (20 ft lbs)
torque in order 1, 4, 2, 3.
b. Tighten nuts evenly to 68 N·m (50 ft lbs)
torque in order 1, 4, 2, 3.
c. Tighten nuts evenly to 217 N·m (160 ft lbs)
torque in order 1, 4, 2, 3.
L08038