Possible Motor Problem?

Dishwasher Repair
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1

Fills OK, but doesn’t run through some cycles, like wash/rinse, and doesn’t always drain. Replaced circuit board - no change:(

Checked resistances on motor windings - main and wash are good, but drain shows 2.5 ohms, wiring diagram says it should be 4.2 - 7.0. 120 volts present at all windings at appropriate times. Motor shows clear signs of past leak from above - but dry now. Does any of this sound like my problem?

I’ve tried just about everything else; motor/pump turns freely, drain open, fills OK, heater OK, door interlock OK, etc., etc.

HELP - I’m getting frantic. (If I call a pro what is he going to do?)

Thx in advance
Dave

2

Hi Dave

If the power coming to the motor and the motor does not work, then there are no questions - the problem is the motor.

If this is what you have with your dishwasher, then the pump and motor Assembly is the part what you needed.

Good luck.
Gene.

3

Thank you Gene - really appreciate the advice.

Got the pump/motor apart - pump looks brand new, motor pretty corroded on the outside but what I can see internally looks OK. Drain hose was apparently loose when the unit was installed new. Went 6 months before it came off. What a mess, but no leaks since (8-9 years.)

Anyway, while I’m at it, I’d like to rig up 120v to the motor just to see what I get, but I was never sure how the reverse sensing winding (or whatever it’s called) works. Is there some way I can test each direction of rotation on the bench?

BTW, motor turns and sound good, ie. no bearing/loose pieces noises, etc.

Thx again

Dave

4

Gene is right on -
Took the bottom motor plate/bearing off just to take a look. Found overheated windings (charred enamel) and some of the winding lacing burned/melted through.

All coils had continuity, as I mentioned before, but the resistance was a little low on one. Kinda subtle.

Thx again

Parts on order from APP -

Dave

5

Keep me updated, please.

Gene.

6

Like Gene said - problem was with the motor. New motor (& pump), runs like a charm.

The fact that the drain winding showed continuity threw me off. Apparently continuity isn’t enough, the resistance has to be right too.

Thanks a mil for the forum, and for Gene

Dave