Power window repair w/pics

[Brian894X4]

Like many folks, my driver's side power window stopped working one day. At first it wouldn't go back up at all, then with some help it would. It started out doing this only once and a while. The culprit seemed to be the window runs as everyone talks about.

But then the power window really stopped working to the point that it sounded like the motor gears were turning, but not moving the window, like the motor gears had stripped out.

After pulling it all apart, I couldn't figure out the problem. The motor worked fine and the regulator and external tracks and gears looked just fine.

Then I tore into the motor and found that the internal gearing in the motor had stripped out.

[Brian894X4]

The power window system uses all metal gears both externally and internally, except for this one plastic gear, which I assume is plastic to be a controllable failure point without damaging other parts of the system, particularly the window.

After tearing it apart, I found further damage with the motor that preceeded the gearing stripping. This picture shows the motor taken apart, but partly cleaned so you can't see all the rust and crap and was inside the internal gearing mechanism.

What it looked like to me was that somehow water got inside and rusted all the metal parts, causing the c-clip to fail, when caused the gear shaft to become loose. This shaft fits in a rectangular hole which keeps it nice and solid, but the hole became rounded and the gear was now wobling around.

It could also be that wear from normal use caused the rounded hole, which caused the gear shaft to become loose, which allowed water inside, which destroyed the c-clip making it worse and rusting everything out.

I suspect this is the root cause of all 80 series power window failures and almost all 80 series driver's side power window motors look like this to one degree or another.

[Brian894X4]

So, I went about looking for a way to repair it. A new motor is something like $285. I had hoped, against hope, that the rear door window motor would fit as a replacement since I don't roll down the rear driver's window (no seat there).

When I tore into it, I found that the motors were different (no surprise) but not much different. They were indentical, except for different plugs and the motor gear arrangement was simply reversed for some reason. I found that I could in fact swap out the internal gearing mechanism between the two motors.

Here's a picture of the rear door gear motor with the gear mechanism cap popped off. Notice how nice and pristine it is inside? I can only guess this was due to it's lack of use and wear.

[Brian894X4]

So, I basically just popped out the better condition gears from the rear motor and put them into the front window motor and then swapped in the old worn and stripped gears into the rear window motor.

Here's a picture of the front motor with the "new" rear motor gears in place, dust cap read to reinstall.

After swapping gears, the rear motor with the bad gears was reinstalled and the door put back together with the window in the up position. Power to the motor was disconnected, so I don't accidently roll it down and all is good. I never roll down that window anyway, so it's no problem.

The new "rebuilt" motor was reinstalled in the front door and the tracks were readjusted to factory specs. The window runs were thoroughly cleaned and lubed and now the whole thing works perfectly.

I plan to replace the runs as soon as I can order a set from C-dan, since they were probably a major cause of the failure.

However, one major lesson learned here is that the window gear mechanism in all these 80 series windows that are slow or stop working is probably the major culprit. I've read mention of the gear being loose and folks wondering if that was normal. That answer is no, it's not normal at all. The gear should be rock solid. It's loose, because the gear shaft is worn and/or the C-clip has come loose.

The best thing about this fix is that it didn't cost me a dime and my front window works good as new!

[flintknapper]

Just a question....but, did you check with C-Dan to see if the plastic gear is available separately?

[mainemike]

Thanks Brian for a great write up. So you're suggesting by replacing the window runs early (when the slow-role-up symptoms appear) we may prevent the plastic teeth from shearing under the increased resistance?

mike

[cruiserman]

I would get a motor from a Toy vehicle in a junk yard and swap in the good parts to the rear motor.

[Brian894X4]

I haven't checked with C-dan yet to see if that gear is available, but I'd be extremely surprised if it was. The motor doesn't look like it's serviceable and the metal cover has to be pryed off. There's no screws, so I'm betting it's sold as a unit only. What I would need is the plastic gear, the round metal gear guide and the gear shaft as all were worn or destroyed.

I don't recall anyone else posting having stripped the gears, but I would definately replace the runs early based on the threads I've read as they are cheap and easy to replace. If the door is apart, it's not super difficult to pull the motor and track out to at least examine their condition. Most people may not have dug deep enough into why their window quit working to find that the plastic gear stripped out and this might be more common that we realize. Because mine only partly stripped, the motor would still partly work, but made a clicking noise and got hung up when the stripped part of the plastic gear hit the metal worm gear of the motor.

I will eventually permanantly fix the rear window, and junkyard parts are a good suggestion, but like I said, the driver's side rear seat is out of the car as I use that area for storage, so I don't have any need to roll down that window.

[Blue Phoenix]

Man, great write up and pics.

[Jumpmaster]

You the man - well done!