"jim" wrote in message ...
snip

I say its the check valve it the problem...... the check valve on mine
went out and did the same thing(overloaded the motor) if it was the
unloader not working even without air in the tank a defective unloader
would not let the compressor start and would draw too many amps and blow
the fuse or set off the circuit breaker.....

It COULD be either one! Some compressors are "self-unloading" and depend on
the check valve to keep the pressure from coming back. Those using an
unloader valve depend on BOTH. My Craftsman oilless started doing that after
transporting it, found the 1/4" tube to the unloader had been bent, moving
the unloader so it didn't activate when the switch shut off the motor.
Result: blown breaker. Readjusted unloader bracket, it's been fine ever
since.If the check valve were bleeding a little pressure back through, the
unloader valve should handle keeping it bled off until startup time.
Nahmie