Defroster Motor

[Joe Flanagan]

I was attempting to take apart my defroster motor so I can rewire it. Got the thing out but was wondering how it comes apart. There's a set screw on the hub in the middle of the fan which I was able to get off, but the hub itself seems like it's frozen on there.

It also looks like it might come apart in two halves but it doesn't seem to want to budge. Has anyone ever taken one of these apart?

[bamfordsgarage]

Hi Joe, I had a similar heater motor to yours (not Mopar) apart some years ago. How to split open the case should be more obvious once you remove the squirrel cage.

The cage hub is intended to slide off the shaft once the set screw is removed. Your hub is obviously rusted in place. I would heat the hub a few times with the propane torch in hopes of breaking the bond. Have heard that heating the stuck parts with a gentle torch and then spraying the interface with WD-40 has two benefits — rapid cooling to thermally shock the rust bond, and a tendency to draw the WD-40 into the joint as it cools.

Whatever, you may have to rig up a puller of some sort, or pry the cage away from the motor (careful to not bend the shaft or the cage), or tap the shaft out of the hub. If the latter, be careful not to mushroom the end of the shaft with your punch — a brass or aluminum punch would be best here.

[DJ194950]

hi again joe,

yes it did remove that squirrel cage several months back to change my motor to 12 volt.

it was a hastle. soaked in penetrating oil overnight, then held between knees while i used a hammer and punch to hit shaft, moved about .002 in. no more.

soaked oil again. hammer and socket used to move it back .002. put flat stock accross under cage ,both sides, in vise. hammer and punch moved about .005, drive on, oil, drive off, etc,etc.

after about and hour with many breaks,coffee etc, it came off.

but you are ahead of me as your setscrew came out. i had to put the heat wrench to mine just to get the screw out.

attached pics as what ahead when you did get all apart

if parts are needed/damaged let me know these parts all appear good if you need them.

good luck,

doug

[Joe Flanagan]

Thanks very much, Doug and Chris. I figured the answer might be getting the hub off. I'll try the heat thing and see what I can do.

Oh boy!

[Joe Flanagan]

Over the last few days, I've been shooting PB Blaster into the hub. I let it alone for the past week. Today, I picked up the defroster motor, took the cage in my hand, and it slipped right off, hub and all. Surprised the heck out of me.

[RobertKB]

Over the last few days, I've been shooting PB Blaster into the hub. I let it alone for the past week. Today, I picked up the defroster motor, took the cage in my hand, and it slipped right off, hub and all. Surprised the heck out of me.

I am a recent convert to PB Blaster in the last year and am sold on the product. No more WD-40 or any other penetrating oil for me. I am amazed at how well PB Blaster works.

Good luck on your heater motor project. It is amazing how many "little" projects there are in a "big" project!

[DJ194950]

i'm going to have to find some of that pb blaster stuff. much better than beating on parts.

readily available??

thanks

doug

[greg g]

ace, true value and do it best have it also. I have seen it in a gallon container with a hand sprayer instead of aerosol, cheaper by the ounce also. But I think it was at NAPA.

[Joe Flanagan]

Finished rewiring the motor with brand new wire and it runs like a top. Used light oil on the bushings and cleaned up the commutator head. Tested it with the battery and it really spins. Now to install it and hook up the duct.