Cause: There is air or water in the pump body, or the bottom valve is not closed.
The water is not filled, the vacuum pump packing is seriously leaked, and the gate valve or the door is not closed tightly.
Remedy: first press the water up, then fill the pump with water, then turn it on.
At the same time, check whether the check valve is tight, and whether the pipeline or joint is leaking. If the air leak is found, apply lubricant or blend paint at the joint after tightening, and tighten the screw.
Check the oil seal ring of the pump shaft. If the wear is serious, replace the new one. The pipeline is leaking or leaking. The nut may not be tightened when it is installed. If the leakage is not serious, apply cement in the place where the air leaks or leaks, or apply the cement slurry mixed with asphalt oil. Temporary repairs can be applied to wet mud or soft soap. If water leaks at the joint, the nut can be tightened with a wrench. If the water leaks seriously, it must be reassembled and replaced the cracked pipe. Reduce the lift and press the nozzle of the pump into the water for 0.5m.