Komatsu PC88MR-10 Shop Manual page 391

a The control valve spool of the travel motor circuit
is an open type circuit, so the remaining
pressure in the circuit can be released by
performing the same operation as that described
in preceding "Releasing remaining pressure in
hydraulic tank".
Releasing remaining pressure in swing cylinder
circuit
1. Release the remaining pressure in the hydraulic
tank. For details, see preceding "Releasing
remaining pressure in hydraulic tank".
a Leave the oil filler cap of the hydraulic tank
removed.
2. Turn the starting switch to ON position, set the
work equipment lock lever to FREE position, and
operate the swing pedal to the right and left.
a The control valve is operated by the pressure
in the accumulator. But the pressure in the
accumulator is used up after the work
equipment control levers are operated 2 to 3
times.
3. Start the engine and run it at low idle for 5
seconds to accumulate the pressure in the
accumulator.
a The engine does not start unless the lock
lever is set to LOCK position.
4. Repeat above steps 2) and 3) 2 to 3 times, and
all remaining pressure is released from the
piping completely.
Releasing remaining pressure in blade cylinder
circuit
1. Release the remaining pressure in the hydraulic
tank. For details, see preceding "Releasing
remaining pressure in hydraulic tank".
a Leave the oil filler cap of the hydraulic tank
removed.
2. Turn the starting switch to ON position, set the
work equipment control lever to FREE position,
and operate the blade control lever to forward
and reverse.
a The control valve is operated by the pressure
in the accumulator. But the pressure in the
accumulator is used up after the work
equipment control levers are operated 2 to 3
times.
3. Start the engine and run it at low idle for 5
seconds to accumulate the pressure in the
accumulator.
a The engine does not start unless the lock
lever is set to LOCK position.
4. Repeat above steps 2) and 3) 2 to 3 times, and
all remaining pressure is released from the
piping completely.
PC88MR-10
30 Testing and adjusting
Hydraulic system
30-41