Lan-rear windows, motors, and trim panels - regrease and renewal

ATL_Alan

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renew all this rear area

you can see the critical elements to be removed marked with arrows

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anotar las conexiones del motor y soltarlas

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before undoing these last bolts use the electric power to completely open the window to manipulate it and to remove it folded

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then you should remove the glass, it will be difficult due to the fact that the glass and the rubber and the metallic plate had glued one to the other, a sharp and long blade and you cut the rubber (new rubber elemnts needed)
the two red fixing bolts are only accesible from the "back" side, and there you find access dificulties because the metallic suport is there, you will have to manually operate the mechanism

Hi, I realize this thread is ancient but I'm trying to replace my rear window motors (I've already done the front motors). If you remember, how did you get that top wooden trim piece off? In the front, I just wiggled it back and forth and it started moving up; then I slid it back a bit and it came right out. The one in the back isn't cooperating (and yes, I've taken the small screws out); I've tapped the black bottom section (not the wood) with a rubber mallet and wiggled it back and forth and it's not moving. Obviously I don't want to get too aggressive but it has to come out. The window is in the full up position. Do I just keep tapping it or is something else holding it in place?

Many thanks, Alan
 

HB Chris

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Are all switches hooked up? If one of them is removed they won’t work. Run a jumper wire directly to the motor to test the motor. Circuit breaker under dash is pushed in? Pushing down on glass while using switch can help, this was the issue on my Chamonix, I could hear motor click but it wouldn’t move.
 

ATL_Alan

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I connected the new motor and it works, so power is getting there, the original motor is not moving. I’ll go out in the morning and see if I can push the window down down while holding the switch down. Hopefully I can get it moving.
 

ATL_Alan

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Not working; the motor doesn't make a sound and the window doesn't move. It has power since I hooked up the new motor stand-alone and that runs. I tried the driver's side and, while it was glacial, it did move and I was able to get it all the way down with some manual assistance. I was also able to see the trim screw for the top piece (that has the wood on it).

So, any ideas on how to get this window to move? I'm trying to take off the sill plate where the door latches to see if I can get behind it but those screws are really in there. I've sprayed with Penetrating Fluid and am letting it soak in.
 

Laldog

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I had good luck using a jump pack connected directly to the window motor tabs/outlets. (Actually I used small wires with alligator clips on each end.)
Hook up the wires first and then power up the jump pack using the jump pack on/off switch. Just a quick jolt so you don't smoke the motor. Reverse the polarity of the wires if the the first try doesn't work.

If that doesn't work, and your window motor looks like mine, you can take the cover off (inside the red box) carefully removing the 3 screws. Turning the gears inside should move the windows up and down) It should also give you and idea how much crud and dried grease etc has accumulated inside the "gearbox"

It's been years since I took out the window assembly, but laboriously cleaning the guides resulted in minor advances in window speed.
Not sure its worth the effort of taking it out.
 

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ATL_Alan

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Thanks, this is really helpful. My motors do look like yours so I'll give these suggestions a try. I took out the driver's side assembly yesterday which is really a masterpiece of origami design. Everything folds in on itself and manages to cover up everything related to disassembly. I was hoping the exercise would show me another way in on the passenger side but so far hasn't.

So I'll give your suggestions a try and hopefully that will get it moving. Thanks again.
 

ATL_Alan

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Great success! I didn't use any of the suggestions (although much appreciated since I was really running out of ideas) as I wanted to keep exploring to see if there was a straightforward way to remove an inoperative rear motor and there is:

On the later style motors, the bottom is enclosed in a black plastic case. Take a flat-blade screwdriver and insert that at the top of the case and start prying it down. It's not fixed, it just slides in place. With the microscopic BMW tolerances you have to pry and wiggle and pry and wiggle and pry and wiggle away from the regulator plate but eventually you'll be able to slide it off entirely, exposing the actual motor. Between the lower side with the motor and the upper side with the plastic toothed wheel (exposed at this point by removing the three screws on the back plate), there are two upside down slotted screws holding the two sections of mechanism together. Unscrew them and then pull the motor down; that pulls out the screw post holding the plastic toothed wheel in place. At that point you can pretty easily turn the plastic toothed wheel and bring down the window. I used small long-nose Vise Grips with each of the noses in opposite holes in the plastic wheel, and turned it while pushing down on the window.
 

ATL_Alan

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Great, glad you figured it out!
You're telling me! Once I pull it entirely I'm going to test the motor to see if was completely dead or just totally gummed up with crud. The other side was pretty bad but seems pretty zippy with the original motor after cleaning the tracks and regulator mechanism. I've got new motors for both sides and will be installing them since the hard part is getting the regulator/window package out and then removing the window.
 

Mark Jarman

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This is a great thread. My rear windows look and function like new thanks to the guidance of this thread. I didn't install relays for the windows, but I did need to purchase some new switches for the window motors to function quick and reliably.

Many thanks to @deQuincey and all who contributed to this tread!

Mark
 

Stevehose

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Relays are a game changer - more amperage to the motor without going through the switches makes them jump to life. I'll race my oem sardines vs. e28 any day :cool:
 
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