Coupe Rear Window Motor - Looking Expensive!!
 

Right hand (coupe) rear window became intermittent two weeks ago and then stopped completely. It had previously been working very freely.

Checked today and found;
a) fuse OK.
b) power at front window switch (interchanged with others).
c) power at rear window switch.

Continued to investigate and removed rear side panel and exposed window motor.

With the inner panel removed I thought I could hear the motor 'energising' but absolutely no movement.

Nothing visually wrong but I could not help myself and thought I would try and remove the motor to see if that would spin on its own.

Obviously the motor is integral to the gearbox as it does not just come apart when the screws are released!!!!!

God knows what damage I caused in attempting this but I gave up and put it all back together.

Something definately went wrong as it blew the fuse also disabling the left hand window that was previously working giving me a slightly bigger problem.

Is it possible for the window motor to just die? Are they repairable?

A very expensive specialty coupe part no doubt!

P.S. Not much working room in the back area of a coupe.

89 300CE
156k kms

Sorry to be of no help here but just to pass along a story - I once had a mechanic, a good mechanic, tell me, in all seriousness, to NEVER, EVER lower the rear window of a 124 coupe UNDER ANY CIRCUMSTANCE, not even a little bit. For if I do it will eventually break and have to be repaired - a repair of such magnitude and unpleasantness that it could never be justified by any amount of fresh air. I took this to heart and have never had such a repair. Good luck.

coupe window
 

that's b.s. I lower my window all the time.... get a new mortor if your went out.

I agree with lee.
the windows are meant to open.
If the window motor gave up after 16 years (assuming bigblue is talking about his 89 300), then is not a big deal.
I know they are expensive, but a trip to the hunk yard and some bargaining cab gets you an operating used one for $50.

Any chance of you sending me a pic of the motor? I am going north tomorrow for a couple of weeks and up there at my parents' house I have stored about 8 or 10 window motors from an old Merkur, the same vintage as your coupe. They fit my old 190e perfectly. If I can get a match, I'll send you one free. PM me.

May Be Hope After All
 

To share my recent (Sat/Sun) story with you . . . after testing, similar to what you were doing, I took my motor and regulator out. Direct battery voltage and ground to first one combination then the other. Nothing. Removed the regulator and repeated the above. Motor spun both directions. Put it back together after a little service and it is working fine. In my case, I had run the window down and it was bound at the end of its stop. By releasing the pressure it works. May have a problem later yet so far it is working properly.
Steve

Broken Window Motor
 

Benzfan, you're a champ (I'm in Australia) however I cannot send you a pick as it is all put back together which is quite a complicated thing on the coupe with seatbelt retractors and seatbelts all part of the matrix.

It is obviously a special unit as the gearbox drives a wire that loops around the mechanism (like a fan belt).

I can't even find a very good reference to the unit on the CD service manual.

If you can take a picture I should be able to remember. I am quite confident that otherwise my chances of finding a 2nd hand unit a slim to none. Nothing on Ebay and I am checking around Australia.

My concern is that by trying to remove the motor I have seriously damaged the internals. I lifted it about 2cm before realising this was not good. It seemed to go back down OK but then the fuse was blown knocking out the LH front window.

Thanks again

89 300CE
156k kms