OPERATOR'S MANUAL MAINTENANCE

Section E - Hydraulics
Slew Motor
Fault Finding
E-135 E-135
9803/9880-3
Fault Finding
Motor Does Not Rotate
Motor Rotates in the Reverse Direction
Motor Speed is Low
Symptom Cause Remedy
The pressure is low. The relief valve is not set correctly. Set to the correct value.
The relief valve does not work properly.
Plunger sticking. Repair or renew the plunger.
Plunger orifice contaminated. Dismantle and clean.
Plunger not seating correctly. Renew the plunger seat.
The pressure is correct but no
rotation.
Overload protection operating. Remove the cause of overload.
The moving part is burnt. Check and repair the piston/shoe,
cylinder/valve plate, etc.
No release pressure acting on the rake. Check and repair the circuit.
The brake piston is sticking. Dismantle and clean/repair.
The brake friction plate is burnt and
sticking to counter plate.
Dismantle and renew the damaged parts.
Symptom Cause Remedy
Reverse rotation. The motor has been incorrectly
assembled.
Check step 16 of the Assembly procedure
to verify that the valve housing 303 and
main housing 301 are in their correct
relative positions. Rectify if necessary.
Inlet/outlet hoses reversed. Re-locate hoses.
Symptom Cause Remedy
Slow rotation. The oil flow volume is low. Check the pump output and the circuit to
the motor.
The temperature is high and leakage is
serious.
Check the oil cooling circuit.
The sliding parts are worn out or broken. Renew suspect parts.