Rear window motor removal

[acat2002]

I have finally freed up enough garage space to start working on some "quirks" that bothered me all summer. I'm going to go through the electric system over this winter making sure harneses are okay, insulation is good, grounds are not corroded etc. Of course my coupe has all of the normal electric issues (windows, wiper motor etc.). I'm starting with the inoperable rear windows.

I have the shop manual (Blue Books) showing the procedure for removing the rear window motors, but the procedure includes lowering the windows to access a small screw on the inside (Sec. 51, Pg. 37/2 for those with the books).

My trouble is that the windows are both stuck in the up position. Is there a method of either manually lowering the rear windows, or "jumping" the rear window motors to life? I find it odd that both motors won't work at all, so it's probably an electrical issue in the harness or ground/fuse problem. Regardless, I still need to access the motors and in order to get the panel off will need to somehow crank the windows down.

Anyone here run into this? Tips? Pitfalls?

thanks,
Aynsley

 

[bert35csi]

If you can hear the motors clicking then chances are the wiring is not the culprit. Have you try rapidly clicking the switches back and forth to jog free the motors? To manually lower the window mechanisms, turn the white nylon gear and turn them one way or the other to lower. This is a slow and tedious process so be patient.

Bert

 

[DJSimca]

chances are they'll work just fine when you loosen them from the closed position by turning the white nylon gear

 

[bmwmadman]

Anysley

There is a chance you just need to excercise the windows. The rear ones rarely get used and therefore tend to freeze up. I had the same issue.

Remove the small 1.5 in cap near the arm rest and play with the white nylon gear. You might also try hitting the switch at the same time. (just wear gloves so the gear doesn't eat your fingers) Try getting the windows loose and working. Roll them up and down for a several minutes....

Hopefully this works and just remember to roll them up and down a couple of times everytime you drive the car. I hope this solution works so you don't have to invest dollar.

Gary

 

[acat2002]

Bert, Gary, DJ - thanks for your help.

As it turns out, the motor (I only got to one side today) was completely frozen. I cracked the black plastic motor case only to find out later that a little more patience would have done wonders. That black plastic was so brittle, maybe not though. Motor assembly is surprisingly simple! Ultimately, the cuprit was a combination of FROZEN BRUSHES and CORRODED/RUSTED BRUSH SPRINGS. I managed to salvage and rebuild the passenger side motor.

Cleaned out all the gummy, waxy grease from the motor worm gear and window guide channels and wiped down with thick synthetic 2-stroke oil (Motul Ester) because it was the only thing handy. Bench tested and it works great. The entire assembly including the window installed and the guide channels works great. I still have the problem of the cracked black casing to the hastily rebuilt motor, so I'm probably going to replace the motor with something I can rely on while it is on the bench.

Anyone have any suggestions? e.g. does any old E3 window motor work?
Like most things, I tend to learn the hard way and although now I can probably rebuild the driver side motor with ease, I'm still left with a suspect passenger-side motor.

As an aside, I noticed how much dirt and shit gets lodged in the lower portion of the window bay, base of the door post and rocker area. It is no wonder these cars rust (this stuff is like a water retaining mechanism whenever the care sees rain). I completely cleaned this dirt and debris out and may take this a step further and do some rust prevention while I have all this exposed. It is surprisingly rust free for having so much dirt lodged in these crevases. If this car had been a daily driver in a northern climate the entire car would be completely gone I'm convinced. I consider myself lucky that it is very solid.

I'll post some pictures when I can.

Thanks Again

 

[acat2002]

The window motors that cam eout of my coupe look nothing like the ones in the Blue Book shop manual, or like anything members have described in this site.

Bosch P/N 0130 820 019 (this is what is stamped on the gear housing)

I'm wondering if mine have been upgraded/swapped out for a later-model version or what. either way, I'm looking for a solution. Don't need the factory-correct units if they are hard to find. I just need two window motors that work. If it is more economical to replace these motors with E34 units - fine. I've also heard that certain porsche window motors are interchangable with some early BMWs. What is the path of least resistance?