Re: Repairing rough running 5 HP single phase motor

You could hit it with a grease gun, run it for 15 minutes or so with no load, see what happens. Problem is that you need to flush the old crud grease out. Only way to do that is to run the old grease by the seals, not a good thing. $28 for two new bearings plus $12 purchase price is still a very good deal.

The headstock bearing on my 10" Logan lathe was similar. Crudded up bearings, really sounded rough. Soaked it for a couple of days in laquer thinner, spun nice and free. As soon as it dried out, back to crud stage. Someday I'll clean it with MEK or something with real punch, in the meantime, the new bearing is working fine.

Ignoramus6689 wrote: 
On Tue, 09 Aug 2005 13:51:13 GMT, Lloyd E. Sponenburgh <lloyd.sponenburgh@xxxxxxxxxxxxxxx> wrote:

"Ignoramus6689" <ignoramus6689@xxxxxxxxxxxxxxxxxxx> wrote in message news:Rl2Ke.46490$JS3.36159@xxxxxxxxxxxxxxxxxxxxxxxx

For $12.00, I bought a 5 HP, SINGLE PHASE Baldor compressor motor that
has a problem. When I spin it up by hand, it turns, but a little
roughly and then spins by itself, but not for very long. It stops too
soon. It is not, by any means, seized, but there is too much friction
compared to what it should be. I did not run it under power yet

It is ball bearing based, which I concluded after seeing grease
fittings on it.

My hope is that it should be an easy fix. Either the grease caked, or
perhaps the bearings need replacement. Any thoughts on how to proceed?


I did the same just a few months ago. I was bequeathed two complete(ly broken) and water-damaged 5HP compressors. Both had Baldor motors. One motor was well and thoroughly burnt out. The other was "grumbling" like yours.

It's a little of a trick to get the motor apart and get the bearings out, but no big deal. The hardest part will be to get the shaft end bearing off the shaft, since it usually corrodes in place. Lots of oil and fine grit paper are the trick to getting the shaft back to its original o.d. without damage. You'll need a small gear puller to start the bearing moving on the shaft. Then it should slide off easily. 


Thanks.

My 5 HP motor is not corroded, as such, and not oily. It looks awfully
like the 3 HP Baldor motor on my home Curtis compressor:

   http://igor.chudov.com/projects/CurtisCompressor/

or here

   http://igor.chudov.com/projects/CurtisCompressor/02_Installed/dscf0004.jpg

only the 5 HP one is bigger. I will try to check it out tonight.

I have a gear puller of some sort, not sure if mine is big enough.


The bearings are stock NGK items in my local bearing shop -- about $14.00 each. 


Thank you. What is NGK?


Take care pressing them back into their seats -- they aren't tight
fits, but you should avoid any pressure on the inner race.  Make a
tool, if you aren't lucky enough to have a bearing pressing mandrel
that fits.  A large wrench socket that is no more than, say, 0.050"
smaller than the o.d. of the outer race will work well as a tool.



Thank you. So, your vote is to just replace the bearings, not to try
to just re-grease them?

i

.

Relevant Pages

  • Re: need stuffing box advice,..
    ... Does anyone know what kind of stuffing box this is? ... not have a cutlass bearing but a bronze bearing in the tube end. ... has enough clearence 10 thousands over the shaft to allow grease to ... down the section of the shaft in the stuffing box a couple thousands ...
    (rec.boats.cruising)
  • Re: need stuffing box advice,..
    ... For those of you that have stuffing boxes that need greasing... ... not have a cutlass bearing but a bronze bearing in the tube end. ... has enough clearence 10 thousands over the shaft to allow grease to ... down the section of the shaft in the stuffing box a couple thousands ...
    (rec.boats.cruising)
  • Re: zerk fittings on motor?
    ... "To grease or not to grease?? ... Large motor frames aways seemed to have a grease passage into the bearing ...
    (rec.crafts.metalworking)
  • Re: Sleeving lawnmower gearbox shaft
    ... So I plan to measure the shaft (still nicely shiny) and the plain bearing ... the motor shaft and the blade gear were very nicely ...
    (rec.crafts.metalworking)
  • Re: Taking up play in electric motor
    ... Motor shafts aren't usually considered to be good for grinding arbors ... where axial movement is critical to the grinding operation (thermal ... expansion, balance and bearing tolerance issues, for example). ... will hold the motor shaft securely within the bearing's axial ...
    (rec.crafts.metalworking)