Power Window Motor Repair

Big_John

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I discussed removing the rear window motor in my '70 300 vert here: Removing Motor

The original idea was to just replace with a newer model I had sitting on the shelf, but that didn't work, so let's just fix the old one instead.

The problem was real obvious when I took the old motor apart. The commutator was covered in grease and crap and one of the brushes was stuck and not making good contact.

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I've freed up the brush, but you can see the crud.

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Because it's a worm drive, you can count on a thrust washer of some kind on both ends of the shaft. See the little round piece with the hole in it? That goes down in the end bushing.

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This washer (thicker) goes on the other end. Note the nasty black grease. This was after I started scrapping it out.

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I should have taken "before" pics, but the drive was also coated with the black grease. This is cleaned up and I'm putting the springs back in. I used a drill to push against the spring.

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Filled it with some grease.

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And stuck the drive gear back in.

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Some Scotchbrite got the commutator looking good again.

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Cleaned up the brushes and end plate and now comes the hard part. Assembling the armature into the end plate first... It takes a lot of patience, but you push the brushes out into their holder while sneaking the armature in. Don't forget to add some grease to the end bushing with the thrust washer.

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Next, put the thick thrust washer on and grease the armature shaft.

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And that gets pushed back into the housing.

Drive gets smeared with grease and back into the housing. I didn't touch the endplay adjustment, and the play seems OK to me... Maybe a touch loose, but I left it alone.

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A little more grease for luck and the cover is screwed on.

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Did you use DIELECTRIC GREASE? :poke:
:lol:

Actually, I used some grease out of my 40ish year old tub of NAPA chassis and wheel bearing grease. This was the grease they sold before everyone had disc brakes and isn't the high temp stuff they sold for disc brake cars.

Over the years, this grease has traveled garage to garage with me. It has been used on just about everything I put grease on including my kids bikes and toys.

Probably not on a wheel bearing since the first time I opened it.

There is probably enough left to last to when I have to grease my wheelchair before they roll me off to the old folks home.
 
I must say that non working power windows are a real pain in the *** but taking them all apart like this and getting them to work again is just so satisfying. Well done! It always helps others to do the same.
 
I discussed removing the rear window motor in my '70 300 vert here: Removing Motor

The original idea was to just replace with a newer model I had sitting on the shelf, but that didn't work, so let's just fix the old one instead.

The problem was real obvious when I took the old motor apart. The commutator was covered in grease and crap and one of the brushes was stuck and not making good contact.

View attachment 526487

I've freed up the brush, but you can see the crud.

View attachment 526488

Because it's a worm drive, you can count on a thrust washer of some kind on both ends of the shaft. See the little round piece with the hole in it? That goes down in the end bushing.

View attachment 526489

This washer (thicker) goes on the other end. Note the nasty black grease. This was after I started scrapping it out.

View attachment 526490

Man! Does that look familiar. . . Same issue with the quarter window motor in my '66 convertible.
 
:lol:

Actually, I used some grease out of my 40ish year old tub of NAPA chassis and wheel bearing grease. This was the grease they sold before everyone had disc brakes and isn't the high temp stuff they sold for disc brake cars.

Over the years, this grease has traveled garage to garage with me. It has been used on just about everything I put grease on including my kids bikes and toys.

Probably not on a wheel bearing since the first time I opened it.

There is probably enough left to last to when I have to grease my wheelchair before they roll me off to the old folks home.
Wait.....you have a 40ish year old tub of grease, too? :thumbsup:

IMG_0150_LI.jpg


And yeah, I did the grease thing a few years ago, too. My fingers are still stained.....

IMG_3199.JPG
 
Nice work John...next year I am going to convert mine to power windows if I can find the parts to do it.
 
Now you need to clean up and refresh your other motors, or you will have 1 that is faster than the others
 
Those older power windows with the spring gear heads last forever. The later cheapo puck design was not nearly as good. I always look for those gear heads and use them whenever possible.

Great job documenting the electric motor side of the rebuild. This thread should be made permanent for reference.
 
John: Thanks for this tutorial, gonna have a go at one of my reluctant PW motors. I always make sure I read your posts, wish I had a tenth of that knowledge. Quick question (or two), I see that the Motor you refurbished has the springs instead of the pucks. I can see how the pucks would smooth out the rotation of the drive gear as they would rotate one way for up and back the other way with window going down but the springs are locked in place. So what benefit can they be to the operation of the window? They cannot rotate in their sleeves unless they were horizontal not vertical. Question #2, if I can be so bold, do you have to install the shaft with the worm drive into the body housing before you put the gear in, so that the teeth mesh properly? Or can you insert the worm drive and then rotate to thread it onto the gears? Appreciate the reply, Cam Shaft
 
John: Thanks for this tutorial, gonna have a go at one of my reluctant PW motors. I always make sure I read your posts, wish I had a tenth of that knowledge. Quick question (or two), I see that the Motor you refurbished has the springs instead of the pucks. I can see how the pucks would smooth out the rotation of the drive gear as they would rotate one way for up and back the other way with window going down but the springs are locked in place. So what benefit can they be to the operation of the window? They cannot rotate in their sleeves unless they were horizontal not vertical. Question #2, if I can be so bold, do you have to install the shaft with the worm drive into the body housing before you put the gear in, so that the teeth mesh properly? Or can you insert the worm drive and then rotate to thread it onto the gears? Appreciate the reply, Cam Shaft
The cars after about 1974(?) or so seem to have the pucks in the drive. Earlier cars have the spring drive. When they made the change, I don't know.

I think the springs lessen the shock of hitting the up and down stops.

Dorman was making the drive gears, but I can't find them on their site anymore. You might be able to find some on eBay with a little patience.

Here's a link to repairing the drives. You could use nuts or find the "pucks" on eBay. Either way works. How to rebuild Chrysler Power Window motor clutch assembly

You have to install the motor and shaft before putting the drive gear in.
 
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