|Oil supply of the oil pump is intermittent and there is a faint noise.
||1. Oil level is too low and air has been absorbed.
||Fill oil and increase the oil level.
|2. Suction port is blocked.
||Remove impurities from the suction inlet.
|3. Air release valve is closed, the pressure in oil storage pipe decreases.
||Open the air release valve.
|The plunger and pressure rod rebound automatically.
||1. The check valve port is slightly worn.
||Correct the valve port.
|2. The check valve spring loses its elasticity or is damaged.
||Replace the check valve spring.
|3. There are particles in the check valve port.
||Clean the check valve.
|When using hydraulic hand pump under static pressure, the pressure drops slowly.
||Failure of various seals.
||Check each seal, tighten the screws or replace the rubber ring.
|Cavitation occurs when using hydraulic hand pump.
||Press the abdomen of pump upwards several times.