Compressor/motor stops after building to @ 40lbs.

by Josh Bauermeister
(Nebraska)

I inherited an older upright farm air compressor. I had the compressor pump rebuilt but didn't install it for about 1 year because I didn't need it.

I installed it now and have tried to use it, but the motor will shut down after reaching 40lbs.

I have blown several fuses in the process. The motor runs fine when the tank is empty but slows and shuts down when the tank gets to 40lbs.

If I let the motor cool and push the reset switch then turn it on it doesn't have enough power to turn the compressor pump. If I dump the air in the tank the motor will again run until the tank reaches @40lbs.

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Bill says... whoops, that sounds like the motor.

If it's oil lubed, make sure it's got enough oil in the sump.

If the compressor is stuck at 30 or 40 PSI, here are the most common reasons why.

However, since yours gets to 40 PSI and burns a fuse, that tells me that the motor is pulling more amps than the circuit can deliver.

It may be pulling more amps as the motor can't overcome the load (pushing more air into the tank that's already got pressure in it) and tries so hard it pops the breaker.

Cheers,

Bill