air compressor oil pan

11 years 5 months ago #31 by Bazzy
air compressor oil pan was created by Bazzy
I have a 7hp NAPA air comp. Had been running and not stopping. I replaced the pressure control and the check valve. Turned it on, ran fine, shut off automaticly. Next time it came on it blew the oil out the oil pan on the bottom of the pump. Could this be a faulty check valve? I took the oil pan off and gasket look good, so put it back together and oil still blows out. Any ideas?

Please Log in or Create an account to join the conversation.

11 years 5 months ago #32 by MTR-Admin
Replied by MTR-Admin on topic air compressor oil pan
Thanks for the inquiry!
I would certainly say the Check Valve is typically the culprit when this happens so you were right in replacing it. Typically if it doesn't seal up when the unit shuts off all of the tank pressure will put back pressure on the pump and can cause this to happen.

I would make sure you have no debris in the head, lines and in the check valve, which will cause it not to seal/seat.

Otherwise, just make sure the Unloader Valve on the pressure switch is "blowing off" or unloading the excess air in the line after the unit shuts off. If it's not unloading after shut off you'll have that excess air pushing itself against the pump as well.

Hope this helps as a starting point.
- MTR

Please Log in or Create an account to join the conversation.

11 years 5 months ago #33 by Bazzy
Replied by Bazzy on topic air compressor oil pan
Thanks for the reply!
I called the Mfr. we discovered though talking, I didn't have the stock oil fill plug.
The stock plug has a vent hole in it to relieve crank case pressure.
I ordered one from a dealer. When I get it back together, I let you know if that solves the problem.
Bazzy

Please Log in or Create an account to join the conversation.

11 years 5 months ago #35 by MTR-Admin
Replied by MTR-Admin on topic air compressor oil pan
Great, glad you've found the culprit! I did forget to mention this one fact, that it could be the oil breather is not "breathing" or venting which will cause too much pressure to build in the crankcase. Sometimes it's that simple.
Good luck and thanks again for the question.
- MTR

Please Log in or Create an account to join the conversation.

Moderators: MTR-Admin
Time to create page: 0.130 seconds