Thanks for the post swoo2247,

Does your air compressor look like the one on the below page?

mastertoolrepair.com/stationary-singlest...fn5376rqssi8hesqamg1

Typically this happens for a couple different reasons:

1) Belt is too tight or too loose. There should be only 1/2" deflection when you press down on the belt at the center point.

2) Pump is locked up/damaged. Remove the Belt and turn the pump flywheel by hand. Does it spin freely? There should be some resistance as it creates compression when the flywheel is turned, but it shouldn't be difficult to turn by hand.

3) Check Valve is clogged. I would remove the in-tank Check Valve, which is the one-way brass valve that's threaded in the tank inlet, where your main Supply Tube connects to from the pump head. Many times it becomes clogged due to debris getting inside via the pump head, so it will obstruct airflow and put back pressure on the pump. NOTE! Be sure to drain the tank of air first!!

This should give you a good starting point.

- MTR

Sounds good. Hope it worked for you.