The Evaporator / Blower Motor Plenum Part 2

The front of the cooked one isn't bad at all.

I dressed the commutators of both.

Fortunately both rear bushings were ok, just dry as an old bone.

I walnut blasted the scorched armature and found some of the varnish coming off. I used insulated varnish for windings to try and save this. I could rewind it, but if the magnets have lost some of their field strength then this would be for naught. Sometimes you have to weigh your options.

Both motors need new wires.

I used 12 gauge GXL wire.

The bushings are well lubed before hand.

Goes without saying.

Again lubed that rear bushing before assembly.

One down one to go.

The seared armature smothered in varnish.

The rest assembled like the other one.

Here's the two ready for testing. They both spin just fine according to the calibrated hand test .

I'm going to a current clamp to examine the commutator passing the brushes. This by the way is a really good test to check in tank electric fuel pumps for any problems.

I've got this on a scope. You can use a cheap pocket scope (~$100) for this and do not need a lab scope.

My exotic test fixture. First up is the rare motor (ie not well done).

I have it dialed to 12.6 VDC and it's drawing 12.6 amps spinning in free air and holy cow does it move air. It blew all the dust off the bench instantly, well that's clean now. Actually it's a little unnerving having it spin that fast right in front of me tethered by book friction.

continued in next post.