Komatsu PC2000-8 BACKHOE, Operation & Maintenance Manual

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MAINTENANCE PROCEDURE
MAINTENANCE
4-60
METHOD FOR RELEASING INTERNAL PRESSURE IN HYDRAULIC CIRCUIT 4
RELEASING PRESSURE IN ACCUMULATOR CIRCUIT
RELEASING INTERNAL PRESSURE IN PILOT CIRCUIT
1. After stopping the engine, turn the engine starting switch to
the ON position and move the lock lever to the FREE posi-
tion.
2. Slowly operate each work equipment control lever up to the
stroke end 3 to 4 times.
3. Screw in the hydraulic tank cap.
4. Start up the engine and stop it after approx. 10 seconds
q
Do not raise the engine rotation above 1000 rpm.
q
Hold the work equipment control lever to the N posi-
tion.
5. After stopping the engine, turn the engine starting switch to
the ON position and slowly operate each work equipment
control lever up to the stroke end 3 to 4 times.
6. Repeat the 4 and 5 operation above 2 to 3 times.
q
After the internal pressure is released, screw in the hydraulic tank cap.
q
Do not loosen any piping until at least 1 minute has passed after relieving the internal pressure.