Electric motor under water

I'd remove the motor, disassemble it, clean and bake the components in the oven at low temp for a good long time and then reassemble it with fresh grease/oil for the bearings/bushings.

If it's a ventilated motor (i.e., has slots or holes in the case) you can possibly get away without doing this. Just remove the motor, bring it inside and put it somewhere warm. Give it a few weeks to dry. Don't get impatient, just give it time. Then oil the bearings and test it. Probably it will have survived the experience.

There's a risk you might get a little more corrosion inside the motor using this method, but it's a lot less work.

If it isn't a ventilated motor, it might not even be wet inside, but you need to open it up to check. If it's wet, you need to leave it open so that it can dry.

The above advice assumes that the water was fairly clean. If it was filthy and carried lots of sand, you're going to need to disassemble the motor to clean it.

Best wishes,

Chris

I had similar problems with two air comp motors. Took them off and stuck them in my oven at 150 degrees for a couple of hours. Ran fine for a year until the bearings went south. Just replaced the bearings and ran fine for several more years until someone stole them. Also had three grinders go under.. Did the same thing with them. Two out three worked fine. Third one, lost the cent switch and would not start unless you spun the wheel first

I'd agree with Pete but I think I might short cut things a bit: I'd give the motor a good bath with clean water, dry it out for several days using gentle heat. (I have a spot near the furnace flue that runs about

120 degrees). Then try it out, see if it runs. If it runs, THEN repack or replace the bear> Had some flooding and my cement mixer got inundated. The water rose 6"

I hear tell that submerged radio gear responds well to several clear water rinses before drying, in preparation for inspection.

--Winston

I remember spending the evening once with the nose package of an AWG10 radar cleaning it board by board, in a deep sink before laying the pieces out on the flight line to dry.

Missing screws in a panel allowed salt water to get in and contaminate the package.

After the drying, we put it back together at IMA level maintenance on their test bench. Worked fine.

Back to the original problem, if the motor is TEFC, I'd pull a bell off to let water out and do the oven thing. Get the sizes off the bearings if you choose not to replace and write it on side of motor with something indelible so you can order a set down the road if it starts to sound wrong.

Wes

works?

The classic way of drying electric motor windings is to pass a controlled current from a low voltage dc source through the windings. Simple full wave bridge, 12v transformer run off a variac for power control. Obviously the case needs to be ventilated and an air current helps.

AWEM

This is the single thing WD40 was made for. I'd give it a clear water rinse, couple of gallons of distilled preferably. Then hose it out good with WD40. If it's a valuable motor, dismount it and submerge in a couple of gallons of WD40. Agitate, invert etc so it gets into all crevice. Then drain thoroughly, rotate a few times and drain the other way. Then spray with electric motor cleaner, dry, oil the bearings and test.

The best thing for drying out stuff is denatured alcohol. Rinse with distilled (deionized if you can get it) water, then rinse with alcohol & bake out gently. Re-lube as appropriate. Alcohol is cheaper than WD-40, and doesn't leave any residue.

Doug White

Isn't thee a possibility of alcohol dissolving some of the coatings, such as the armature wire varnish?

I'm didn't spend a lot of time on this but I googled armature and shellac and got a few hits. Alcohol will disolve shellac if I not having a brain fart.

Wes

I have to say I like the excite with low voltage DC approach. That will heat what you want dry -- the windings.

Patience is essential. You could speed things up if you have a large vacuum pump & bell jar and take it up to 33,000 feet for a while....

Actually, that's a good idea. A lot of us have a spare vacuum pump sitting around.