[roger1]

I have a 5hp Sanborn compressor that has served me well since I bought it new in 1989 or 90, so it's nearly 20 years old.

It's an 80 gallon vertical that is 18 scfm @ 100 psi and 16 scfm at 175 psi.

The electric motor went out today. It trips the breaker and sparks inside the cover on top of the motor if I reset the breaker and immediately trips it again.

What should I do?

Is it time for a new compressor?
Or, should I take the motor down to a electric motor repair/rebuild service?
I see there are couple of electric motor places in San Angelo that are in the phone book.
What about buying a new motor, would that be better?

Opinions please.

Roger

[matt167]

rebuild the motor if it is serviceable. if not, look into a replacement motor

[MrPhotographer06]

personally i think its time for a newone

[wildthing]

if its just the motor and the compressior has served your needs , fix or replace the motor.

[oldred]

If the pump is still good and the overall condition of the rest of the compressor is still in decent shape then repairing/replacing the motor would probably be the way to go here. What brand is the motor you have now and what is the amp rating? What about the shaft size? Depending on what motor you have it may be cheaper to just replace it with a new one and from your description of the problem this is likely to be the case, you might try Surplus Center if you decide to buy a motor as they have some really good prices on quality motors.



http://www.surpluscenter.com/sort.as...earch=electric motor&UID=2008122121223447

[oldred]

I just checked out Surplus Center and it looks as if they don't have much right now in the HP range you need but a replacement should not be too hard to find.

[roger1]

Originally Posted by oldred

If the pump is still good and the overall condition of the rest of the compressor is still in decent shape then repairing/replacing the motor would probably be the way to go here. What brand is the motor you have now and what is the amp rating? What about the shaft size? Depending on what motor you have it may be cheaper to just replace it with a new one and from your description of the problem this is likely to be the case, you might try Surplus Center if you decide to buy a motor as they have some really good prices on quality motors.

http://www.surpluscenter.com/sort.as...earch=electric motor&UID=2008122121223447

It's a Century Electric (MagneTek)
22 Amp 3450 rpm 7/8" keyed shaft.

What's the chance it could just be a capacitor that is bad?

[timothale]

My old sanborn has a red reset on the end of the motor housing. My kids turned the breaker on to air up their bikes a few years ago then didn't turn it off. the temp got below freezing and the pump didn't lubricate good enough and scorred the rods and crank when it started up in the middle of the night. The shop was 150 ft from the house and I didn't hear it trying to run. . I ordered new rods. pollished the crank by hand then drilled the rods and made dippers like I put on my old ford flathead. It 's a little noiser now but has been running 7 yeas since I rebuildt it. I had an elect motor shop rebuild the motor on my Turret saw. cost was $120. a new motor was about $ 500. I have redone elect motors in the past . usually if the windings aren't burned I would find a broken wire or the starting points were bad or a capacitor . 2 Hp motors were free and the most I spent for parts was $ 20 to get them running for use on buffers. grinders . and a GIL_BUILt 14 in bandsaw kit I made.

[timothale]

Be sure to check motor rotation, if you decide to buy a replacement. Some of the 220 v motors out there will only run one direction they do not have the terminal block and wiring you can switch to change voltage or direction.

[roger1]

After searching on the net, I found that Century/A.O. Smith makes a replacement motor:
http://www.drillspot.com/products/35...mpressor_Motor

Grainger also has it for $307.

I took the motor down to repair place in San Angelo this morning and they will diagnose it for me and call me later today. They are also a A.O. Smith dealer and have the motor new in stock as well. They guy said if the motor is shot, the new one is the way to go. I didn't get a price from them on the new one yet. I'll wait to ask that until I know whether the old one is repairable or not.

[302 Z28]

A.O. Smith motors are all either from China or Mexico. If that was my motor I would try and have it rebuilt locally some place. Chances are the rebuild would be better IMO.

Vince

[roger1]

The guy from the motor shop called.
Bad news, it's shot.

But it's good news that he carries the replacement.
He quoted me $324 plus tax.
I asked him if he would swap the old pulley on it for me for that and he said he would.
I will pick it up in an hour.

Thanks for all your help guys.

[roger1]

Originally Posted by 302 Z28

A.O. Smith motors are all either from China or Mexico. If that was my motor I would try and have it rebuilt locally some place. Chances are the rebuild would be better IMO.

Vince

Vince,
I guess I'll take a chance with this new one.
We'll see how long it lasts.

[roger1]

It's up and running again. It took me quite a while to put it back on as I was anal about getting the pulleys lined up perfectly.

Seems quieter and vibrates less.
It could be psychological as I just dumped $350 (with tax) into it.

[302 Z28]

Glad you got it running, where is the motor made? Reason is, the other day I had an occasion to go to commercial wholesale AC & refrigeration supply house. They had a stack of A.O. Smith motors about four feet high and at least 30 feet long in the showroom. Everything from fractional HP to 5HP. I looked them all over and there seemed to be no rhyme or reason to where they were made, some in Mexico and some in China. There seemed to be no pattern, you would find a 1hp motor made in Mexico and right next to it a 1hp motor made in China.

Vince