Dead compressor--fix/replace?

[Tony Sade]

My bought-at-Lowe's DeVilbiss 5hp/20 gal oil-free compressor died over the weekend. Worked one day, didn't the next. I can hear something straining to move and the lights in the shop on the same circuit dim considerably when I flip the switch. (I have a dedicated circuit for the compressor; the dimming occured when I moved the thing out from its normal resting place and tried it at a different location.)

Any likely cause that comes to mind based on such little information-anything that tends to go wrong with these? Anything a DIYer can try on his own?

Any recommendations for a replacement? I'm a hobbyist so it will get light use. I use nail guns/pinners/staplers; fill tires; and use a HVLP conversion gun for finishing. Given my small garage shop setup, it really needs to be one of those that looks like a wagon-wheels on the back, handle in front, tank rests horizontally-or something with a similar footprint. The compressor sits under a table which holds my dust collector with a canister that almost hits the ceiling. There's no place else to put it. I really can't spend more than $400 (without having to sleep in the shop).

Thanks,

[Don Bergren]

Any likely cause that comes to mind based on such little information-anything that tends to go wrong with these? Anything a DIYer can try on his own?

I have a Craftsman (DeVilbiss) that developed a similar sounding problem. The lever you flip to turn the compressor on and off also dumps some air each time so the compressor will start with no head pressure. On mine, that valve was not dumping the air so when I turned it on it just strained to start and I turned it off.

I think I used the owners manual to troubleshoot the problem. I ordered a new part from Sears that consisted of the whole "box" deal with the switch paddle and that fixed the problem. It wasn't a difficult thing to fix, but it took a month and a half to get the part from Sears. I believe it cost me around $60.00 for the part and shipping, but it was several years ago and I can't remember for sure. The compressor has worked fine ever since.

[Rob Russell]

It could be the start capacitor on the motor.

[Curt Harms]

I have a Craftsman (DeVilbiss) that developed a similar sounding problem. The lever you flip to turn the compressor on and off also dumps some air each time so the compressor will start with no head pressure. On mine, that valve was not dumping the air so when I turned it on it just strained to start and I turned it off.

I think I used the owners manual to troubleshoot the problem. I ordered a new part from Sears that consisted of the whole "box" deal with the switch paddle and that fixed the problem. It wasn't a difficult thing to fix, but it took a month and a half to get the part from Sears. I believe it cost me around $60.00 for the part and shipping, but it was several years ago and I can't remember for sure. The compressor has worked fine ever since.

The part Don is referring to is called an unloading valve. I had the same combo pressure switch/unloader go bad on a Campbell Hausfield (sp?). I ordered a new one and could not get that cheap piece o' crap to quit leaking:mad:. I found that I could put an unloader valve in the copper line where it entered the tank. I got the valve and pressure switch from Grainger, installed in about 10 years ago and it's worked great ever since.

You can tell if it's the unloader valve by draining all the air out of the tank and system. If the compressor still won't start, there's something else wrong with it.

HTH

Curt

[Bruce Wrenn]

Magic words- "sits under a table that holds my dust collector." My money goes on there being dust in the start switch on the motor. Take end bell off motor and blow switch out. Start cap. would be my next choice.

[Tom Veatch]

If I were going to bet on something, it'd be what Rob Russell suggested. Works one day, don't work the next, straining to start, dimming lights - sure sounds like a bad start cap to me. While you in there be sure the centrifugal switch that cuts the cap. out of the circuit when the motor comes up to speed is OK.

With my compressor, the switch stuck and didn't take the cap. out the the circuit. If the switch is bad, you can bet the cap. is gone too. No quicker way to ruin a start cap.

[Tony Sade]

I took it to the authorized repair shop in town and am awaiting their diagnosis which is going to cost me $20, deductible from any repair charge. I can live with that.

I appreciate all the suggestions, tips, etc.

Tony