Calling APMECH...Motor Question

[dumbswede]

I recently acquired a Bader Space Saver. After tearing everything down, I found that the motor was full of water.
See pics for details. I have drenched all of the rusty surfaces with Phosphoric Acid. I am hoping I can replace the bearings and run it.
This is a nice U.S. Motors continuous duty 3 phase 5 H.P. motor and I would like to try and save it.

Any advice would be appreciated.




Thanks

 

[A_Pmech]

Looks like it was a tad wet in there...

It's hard to say if there has been any insulation breakdown without megging the windings.

The usual procedure is to allow the motor to air-dry for several days and then bake somewhat below the maximum temperature allowed by the motor insulation class for 8 hours or so. Then meg the insulation.

If the insulation tests OK, renew the bearings and clean with electric motor cleaner. Do not use any chemicals which might affect the insulation. Then reassemble and run. If you do not have a megger, simply dry the motor out and test-run it, understanding that it may develop a short to the machine frame which, if not grounded, presents an electrocution hazard.

This paper put out by the Bureau of Reclamation has some guidance on drying motors:

http://www.usbr.gov/power/data/fist/fist3_4/vol3-4.pdf

It's generally fair to say a submerged motor will have a shorter lifespan than a motor which has not been submerged. Just how much less is hard to guess. Needless to say, make sure your grounding and motor overload protection is correctly sized and in working order.

All the above said, if you have the funds I would purchase an NOS motor from Ebay. 3-phase motors are cheap.

 

[dumbswede]

Thank you sir.....