Common causes of failure:
1. TVC valve is not adjusted properly.
2. There is a problem with the excavator servo mechanism.
3. There is a problem with the plunger of the excavator.
4. The excavator plunger pump or servo plunger is faulty.
5. The LS control EPC solenoid valve operates incorrectly.
6. LS overflow or main unloading valve assembly action error, can also cause excavator rotation, low walking speed or lack of power failure.
7. The auxiliary unloading valve operates incorrectly.
8. Misoperation of the main relief valve can also cause failure of the excavator's rotation, low walking speed or lack of power.
9. Excavator control pump circuit hydraulic problems (refer to test and adjustment), can also cause excavator rotation, low walking speed or lack of power failure.
Repair method for excavator rotation, low walking speed or lack of power:
1. Adjust the TVC valve.
2. Replace or repair the servo mechanism assembly.
3. Repair or replace the plunger pump.
4. Correct or replace the excavator plunger pump or servo plunger.
5. Replace the LS control EPC solenoid valve.
6. Replace the excavator LS overflow or main unloading valve assembly.
7. Repair or replace the auxiliary unloading valve.
8. Replace the main relief valve.
9. Adjust or replace the hydraulic components of the control pump circuit
