Method For Releasing Remaining Pressure From Swing Motor Circuit; Method For Releasing Remaining Pressure From Travel Motor Circuit - Komatsu PC500LC-10R Shop Manual

RELEASE REMAINING PRESSURE FROM HYDRAULIC SYSTEM
METHOD FOR RELEASING REMAINING PRESSURE FROM SWING MOTOR CIR-
CUIT
When disconnecting a pipe between the swing motor and control valve, release the remaining pressure from the
circuit according to the following procedure.
1.
Release the remaining pressure in the hydraulic tank. For details, see "METHOD FOR RELEASING RE-
MAINING PRESSURE FROM HYDRAULIC TANK".
REMARK
Leave the oil filler cap of the hydraulic tank removed.
2.
Turn the starting switch to ON position.
3.
Set the lock lever to FREE position, and operate the right and left work equipment control levers forward,
backward, rightward, and leftward.
REMARK
The pressure in PPC accumulator is lost by operating the work equipment control lever 2 or 3 times.
4.
Set the lock lever in LOCK position.
5.
Start the engine and run it with the fuel control dial at MIN (Low idle) position for approximately 10 seconds
to increase the pressure in PPC accumulator.
6.
Repeat steps 2 to 5 several times, and all remaining pressure is released from the swing motor circuit com-
pletely.
METHOD FOR RELEASING REMAINING PRESSURE FROM TRAVEL MOTOR
CIRCUIT
• When disconnecting a pipe between the travel motor and control valve, release the remaining pressure
from the circuit according to the following procedure.
• The control valve spool of the travel circuit is an open type circuit, so the remaining pressure can be re-
leased by performing the same operation as that described in "METHOD FOR RELEASING REMAINING
PRESSURE FROM HYDRAULIC TANK".
1.
Lower the work equipment to the ground in a stable posture, and stop the engine.
2.
Loosen the oil filler cap (1) of the hydraulic tank gradually
to release the air in the tank.
30-62
30 TESTING AND ADJUSTING
PC500LC-10R