Posted by James M. from Sears Seattle/Shoreline:
Hear any air leaking after your compressor is in the off mode? If so you have a bad check valve stuck in the open position. You have air leaking into the head and its to much for your compressor to cycle. The check valve is located from the discharge tube into the tank. Its the last fitting... Check there first. Everytime it turns off you should hear a release of air to empty the head at the pressure switch.
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