Doosan DX700LC, Operation And Maintenance Manual

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OP000030 Troubleshooting
6-4
SWING SYSTEM
All actuators have low
power. Low hydraulic oil level. Add hydraulic oil as required.
Suction filter clogged. Clean filter.
Hydraulic pumps faulty. Contact your DOOSAN dealer.
Main relief pressure too low. Contact your DOOSAN dealer.
Hydraulic pumps excavating. Bleed air from hydraulic pumps.
Only one or two actions
have little or no power. Overload relief pressure too low. Reset pressure.
Makeup check valve leaking. Clean or replace as required.
Control valve spool faulty. Replace valve spool.
Dirt in valve spool. Clean or replace as required.
Actuator failed. Repair or replace as required.
Cylinder seal failed. Repair or replace as required.
Cylinder rod damaged. Repair or replace as required.
Remote control valve failed. Replace control valve.
Wrong pilot line connection. Reconnect pilot lines.
Oil temperature too high. Oil cooler faulty. Contact your DOOSAN dealer.
Fan belt loose. Tighten fan belting as required.
Problem Cause Remedy
Problem Cause Remedy
No swinging motion. Swing brake valve faulty. Replace brake valve.
Hydraulic timer faulty. Replace timer.
Low brake release pressure. Adjust pressures.
Swing motor failed. Replace swing motor.
Remote control valve failed. Replace control valve.
Wrong pilot line connection. Reconnect pilot lines.
Swing motion jerky. Swing gear worn. Replace swing gear.
Swing bearing damaged. Replace bearing.
Improper lubrication. Add grease.