Hydraulic pump solenoid valve 111-9916 proportional solenoid valve

Common faults of excavator solenoid valve

The variable amplitude cylinder of the crane does not rise

First check the indicating value of the pressure gauge, if the indicating value of the pressure gauge is low, and the hydraulic pump's flowline has no oscillation and oil flu, increase the throttle of the pressure gauge, and the indicating value rises, it can be determined that the key to the problem is the hydraulic pump, and the hydraulic pump should be removed. If the indicating value of the pressure gauge is low, the hydraulic pump outlet pipe has oscillation, oil flu, and the indicating value of the pressure gauge has not changed, the cause of the fault is the relief valve, the relief valve should be repaired and the relief valve pressure should be adjusted. If the indicating value of the pressure gauge is normal, it indicates that the hydraulic pump and relief valve are operating normally. The tubing connector in the upper cavity of the variable amplitude cylinder should be unscrewed, inserted into a clean container, and re-operated. If there is rapid oil outflow, it indicates that the variable amplitude cylinder has serious internal leakage, and the cylinder seal should be replaced. If there is no oil flow, it indicates that the balance valve is faulty, such as the spool, the valve stem is stuck, the contact surface of the spool and the valve body has foreign bodies, or there are serious groovemarks, and the seal is damaged. At this time, it is necessary to disassemble, repair and grind the touch surface of the valve core and the valve body, and replace the seals.