260E: Rear window goes up, but not down
 

1989 260E

When it rains, it pours. :)

Earlier today I did a post on my broken sunroof angle lift. Now, my left rear window is *half * broken: I can raise it (with scary cracking plastic sounds as it reaches the top) but cannot lower it – unless I use my hand to push it down. :eek:

Given a choice between immediately fixing the sunroof or the window, I will opt for the window.

Is my regulator broken, or is the so-called “regulator jaws” that I need -- or is it altogether something else? (If the window goes up, but not down, I would assume something on the downward linkage is broken or detached, but I know nothing of windows.)

Anyone? Anyone? Bueller.....? :confused:

take off the door panel, probably a broken regulator, no way to tell unless you take a peek

Thanks.

Would a broken regulator raise the window, but not lower it? Seems like somthing that grips the lower part of the window has become detached.

YES, you have to take off the panel and take a look, it might just be a detached track

Excellent, thanks for the feedback. That will be my saturday project. :)

I finally removed the door panel to see what was going on with this.

The regulator cable is snapped. The motor is fine. Is this repairable?

Except for the regulator jaws, the rest of the assembly is sold as a one-piece unit. Around $250!

Your best bet would be boneyards. You can swap out the motor on the salvage unit with your good motor...

Thanks for the info. I am finding brand new units for about $120.00 from various places, so will probably just get those. Shame to waste two perfectly good motors though.

FYI: Got one used for $75.00 and a new one is on the way from Ebay ($120.00).

Sounds like a straightforward repair, and having already been inside the door panel I know the only "challenges" will be figuring out how to unplug the old motors, and how to detach the existing regulator from the window. I have not seen anything specific in the threads I have been reading this morning.

Any directions on how to do those two things?

ALso, is there a market for the used motors? Whether for cars or some other application where a very torquey motor is needed?

Update
 

Add "Window Regulator Replacement" to the list of surprisingly easy repairs. :) It was not nearly as hard as I thought it would be, and I was able to replace both rear door regulators -- and my rear brake pads and washer pump -- in about 5 hours total, including the usual minor, time-wasting problems we encounter with any repair. Not a bad morning at all.

Both regulator cables had snapped, but the plastic jaws and other parts were in perfect condition. (Should anyone require one or two good W124 rear window regulator motors, send me a message.)

What caused my regulator to fail is one or more strands of the cables broke and began to unravel. This caused them to hook into other cable strands and kink up in the regulator wheels and pulleys, making crunching or "pebbles in the door") noises initially, as the cables moved over and around the plastic parts, before finally kinking to the point of seizure. FYI: This process can go on for years because the window motors are evidently so powerful. They also seem designed to wrench away from the door frame if a cable jams, perhaps to avoid deforming the door frame itself. Both of mine were shorn off at the motor housing.

I read much about potentially damaging the plastic door panel clips (hooks, really) but they are pretty sturdy and so long as you lift up only, you are in no danger of breaking them.

Overall, this is a simple repair.

Glad that the story had a happy ending! I just had the same problem with the RR window on my '92 300E except it would go down but not up. After pulling the panel, I found the plastic attachment on the wire rope had broken so I found the frame complete w/o motor on Ebay, bought it, put my good motor on it, and installed it, works fine. Incidentally, I have these other parts available, frame, wire rope, worm dirve housing that I will give to anyone who needs them, just cover the cost of shipping. Happy to help fellow DIYers! :)

It was certainly one of the more gratifying repairs I have done.

Photos
 

I had almost the same problem with my rear window, and took photos as I was in the process of repairing. The electric window motor shaft was rusted and stuck in place and burned out.

Enjoy the photos!

Photos #2
 

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