1.First, check whether the hydraulic pilot opening prompt appears on the display screen.If it can appear, it means that the pilot stroke switch is good.
2. Check that the pilot solenoid valve is not at 24V after the hydraulic pilot is opened.If there is, the pilot solenoid valve should be checked.
3.If the pilot solenoid valve is good, the main pressure and pilot pressure of the front and rear pumps should be checked (check with a pressure gauge).
4.If the pressure of the front and back main pumps is 3mpa, and the pilot pressure is 0, the pilot pump or pilot relief valve is damaged.
5. If the main pump pressure and pilot pump pressure are, the connected rubber disc or the main pump is damaged.
6.If the main pump pressure rises to 0 and the pilot pressure is normal, the main relief valve is damaged.
7. The final inspection of this machine is that the connecting rubber plate is damaged.After replacing the connecting rubber plate, the machine works normally.
No action of the whole vehicle of the excavator is often caused by the following reasons:
① There was no installation error during installation, the buffer rubber block between the engine and the hydraulic pump was damaged
② The main shaft of the hydraulic pump is broken, or the servo system has a problem, especially the adjustment of the regulator in the hydraulic pump
③The installation of the fork is wrong or the adjustment amount is too large during debugging, causing a break
④ The connection block with the engine is reversed
Of course, the specific reason why it needs to be investigated on the spot.
After the technician's on-site troubleshooting, it was found that due to the damage of the buffer rubber block between the excavator engine and the hydraulic pump, the Cat 330C excavator had no action failures. The machine resumes normal operation.
No excavation of the whole vehicle of the excavator:
1) Check if there is 24V voltage at the pilot cut-off switch.
2) Check whether the pilot solenoid valve is intact and the voltage is normal.
3) Check whether the pilot spool is stuck.
4) The outlet pressure of the pilot pump was measured with a pressure gauge and found to be only 0.5 to 0.7 MPa, and the spring in the relief valve of the pilot pump was broken during the disassembly inspection.
Doosan, Daewoo excavator has no action failure reason: Pilot pump overflow valve spring is broken, resulting in low pilot pressure.
Removal method: troubleshooting after replacing the spring.
