Circuit breaker keeps kicking out

I have a 4.5 HP 21 gal. compressor. It has been a great compressor. it is used very little, just when i am in the shop on weekends. But lately it will kick the circuit breaker every 3-4 minutes. If i wait a few seconds I can push the breaker and it will run a bit more but it won't go until the pressure is built up. I have to keep re-starting it until the pressure is reached. I understand the circuit breaker concept but what is there that might keep kicking it? Any suggestions would be appreciated.

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Bill says....

David, I've moved your question to the "Compressor Blows Breaker" page. There is a lot of info linked from this page on why your compressor blows breakers, and it doesn't make sense to repeat it all here again.

Look at the info to see if it helps. Still stymied? Based on the info provided on those pages, if you can provide more info on your compressors actions when the fault is occurring we will pursue the cause further.

Cheers,

Bill