Jeff Wisnia wrote:
Jerry Trumball wrote:
I have a GE DDE7208 dryer with a 5KH26JJ motor. When the motor is
stationary, the centrifugal switch energizes the start winding along
with the run winding. When I depress the starter, the motor hums but
does not turn even with the belt off. That points to a bad motor, but
I want to be sure.

Winding resistances are 3 and 4 ohms. That doesn't prove the
insulation is holding up at 120 VAC, but if there were a leak so bad
that the motor wouldn't turn even unloaded, wouldn't the overload
protector break the circuit?

At 2 amps DC, there are only 6 mv across the centrifugal switch, so
the contacts appear to be fine.

Bearings have no slop or noise but more friction than some motors I've
seen. It takes 0.7 inch-pounds to get the shaft moving.

What could be wrong?

Some portions of the motor housing or end caps may have "warped" enough
so the outer surface of the rotor will get pulled into mechanical
contact with the inside of the stator when magnetic fields are present
and then "stick there".

Can you try powering the motor and rotating the pully carefully by hand
and see if it seems "stuck" when power is applied?

Can you disassemble the motor and see if there are any "rub marks" on
the outer surface of the rotor?

I've encountered this phenomena a couple of times over the years.

Let us know what you find,

Jeff

The frame is riveted. Before reassembly I tried looking between rotor
and stator to see if there was dust. The spaces looked even.

After reading your post, I plugged it in and pressed Start. It started
every time. I think maybe oxidation in the damaged stranded wire at the
plug kept the motor from starting, and wiggling the cord has reduced
resistance for now. I'd better get a cord before I try drying laundry.

I have a rattle now. Investigating, I found about 5mm endplay for the
drum. Maybe that's normal. The rattle seems to be coming from the
sheet metal behind the drum, where the heating elements are mounted.
Opening the unit will be much easier this time!