Compressor Motor Repair

[Yohahn]

Well it looks like I did it again. I paid $400 for my cool old Quincy 325 compressor and its gonna cost me a lot more.

I took the motor in to be gone over and it needs a bearing and a switch. I'm not sure what kind of switch is in the motor enclosure, but that's what the guy said. Might have been a little tough to find because its a Leland Faraday which is out of business a long time.

Anyway they want $380 to do that repair. Looks like I can get a new Baldor for $360. This is for 5 hp motors in all cases. But does anyone here think this is a work I could do on my own. I was always under thge assumption that electric motors are a fairly simple animal. I'd like to keep this old motor off the scrap heap because its very robust and I hate to see old stuff tossed because its cheaper to buy a new one that's probably not as good. Just seems like a big bill.

I understand people have to make a living, but more and more I've been stunned at what people want to charge. I run trains for a living and work 8 hours for $269 before tax. I have a lot of responsibility and a license to protect. So that's nearly two days of work, considering the tax man's cut, to repair an electric motor that did work when I took it off the machine.

So back to the question. You think that I can find what I need to get this done parts and knowledge wise.

 

[marinusdees]

Take it apart and look at it. It's not rocket science or brain surgery. With reasonable care, you can pull the old bearing and press in/on a new one. Find a local bearing house, there are plenty around. With the number off the bearing, you can buy a new one for a lot less than $300. More than likely a very common, cheap bearing. I assume by switch it means the centrifugal or governor switch. You can probably adjust(bend) it and emery the contacts and it will work. If not, a local motor repair shop should be able to supply one. Good luck.

 

[marinusdees]

PS As long as you have it apart, replace both bearings. Keep and replace wavy washers exactly as removed.

 

[Jim Pelosi]

I repaired my HVAC motor in my furnace. It came with cheap china bearings that blew out after only 3 years. I pulled the end caps off , popped out the bearings and bought them to the local bearing guy. $16 later I was up and running.

Sent from my SM-G360P using Tapatalk

 

[marinusdees]

Some more advice. If you can't repair or replace the start switch, there is an electronic device called a Sinpac which is a replacement, but not especially cheap. It is less troublesome than the mechanical switch, but must be sized to the motor. If the motor has the nameplate so you can determine the so-called "name plate rating" that should suffice. If not, you'll have to determine the current draw, which requires running the motor and using an ammeter. Let me know how it goes, I may be able to help you.

 

[gungatim]

I've fixed a few motors myself, bearings aren't too tough to replace, I know you can buy some switches (common ones anyway), but cost was too high so I fixed the ones I had. one was broken from incorrect disassembly, but glued back together, the other one the contacts needed cleaning/filing because they were burnt....

 

[theoldwizard1]

Does it currently work ? Run it till she blows and then buy a Baldor !

OR


Check YouTube. There are several videos on rebuilding an electric motor.


Edit: This is a good video ! Single Phase Electric Motor Diagnosis

Another good one Electric Motor Rebuild

My gut tells me, with some cleaner and some fine emery cloth, you can clean that switch up and it will be almost as good as new !

 

[Yohahn]

I'm encouraged.

Got it all apart and ordered bearings already. I think I spent just over $20 on those. The centrifugal part of the start switch is probably OK. There's also what's referred to as a static switch which actually has the contacts. I see it's been arced a bunch and I'm confident I can get it from a company called Torq. They seem to make anything you'd need ibn these switches. I have an email in to them.

The shop did mention need of one or more capacitors. They ought to be easy to find as tge part numbers and specs are clear. There's 2 Mallory 540 mfd and 2 341 mfd. The 341's I would guess are the run capacitors. One thing that confuses me. I've read than start caps will have a range and run caps will be of a specific number. So far in the Grainger book I only see start caps with ranges. Very very close to matching my needs but not exact and nothing that says run. Any experience out there on this.

Also, thanks very much for the replies.

Joihn

 

[marinusdees]

Voltage rating on a cap is more important than exact capacitance match. Be sure any replacement caps have the same (or higher) voltage rating. Get close on capacitance match. Grainger is a very expensive place to buy caps. Surplus Center in Nebraska has a wide selection at better prices. Or, try flea bay. I wouldn't replace capacitors which are OK. That said, it's beyond the parameters of this forum (for me , anyway) to give you instruction on how to do this. Again, it's not rocket science. Maybe another member of this forum will chime in.