Air Compressor inop

[Frankb]

My 40 year old Craftsman 30 gallon 5 hp compressor failed. Getting power just wont start up.

Was running fine. It starts and stops as you use air. Noticed my high speed was slowing down and did not hear the motor running. Thought it might have overheated so put a fan on it for an hour. Still no start.

Any ideas on what to look at?

This machine has run flawlessly since I bought it from Sears in about 1985. Man the stories it could tell...

 

[dadsbee]

Motor got a capacitor for start... always it ! Unless you cooked the windings...

 

[BeepBeepRR]

I have a 5 year old Husky that i recently had to replace the capacitors on. You got lucky for that length of time. My old craftsman blew out the reed valves. Buy the capacitors on line cheaper..

 

[Dako]

I would check the pressure switch (aka: 'points)... usually located under a cover that the wires go to. The contacts can get corroded, just like an old distributor. It's where you can also 'tweek' the max pressure build cut-off.

 

[71RRHI]

Start at the pressure switch. Make sure you have power coming into the switch. Then check there is power going to the motor. If power in, but nothing out, bad pressure switch. If power in and power out then the problem is the on the motor side. Usually a starting capacitor problem. Usually if the motor is locked up, it will draw to many amps and trip the breaker.

 

[F4R/T]

Buy made in USA electrical parts cheap does work but it can cost ya.

 

[Coronet_Arch]

When looking for parts it helps if you can determine who manufacturered it for Sears. Mine was made by Cambell Hausfeld. I had to replace the pressure switch on it. Picture of the unit would help with the diagnostic.

 

[dvw]

If you drain the tank and it runs, my bet is the pressure switch. If it doesnt run at all the start capacitor is high on the suspect list.
Doug

 

[Don Frelier]

I know everyone is trying to help.
But the first thing to check is that you can turn over the compressor by hand. If it's siezed up then the pressure switch and capacitor won't help.
If you can't rotate it then disconnect the belt and the motor will likely run fine.
Then you'll need a new compressor head.