For several months, I have been ordering my fast food by opening the door. For quite some time the driver's window has remained stationary, even though the motor runs. I had been too lazy to take the door apart to see if it was the $5 slider problem, or the more expensive regulator problem. Since my wife may be driving this car some in the future, my motivation to find a solution was getting higher. When I saw a replacement regulator on Amazon for less than $40, I jumped.

Sure enough, once I got in there, I discovered that the welds on one of the regulator arms had broken, so the toothed arc moved without moving anything. One of the reasons I went ahead and bought the regulator was reading that this was not uncommon, since the driver's window is the most used window on the car. Yay! I guessed right!

I didn't take any pictures, because my phone was charging, but here is what I learned in the process.

1. Getting the door panel off was harder than I expected. There are a lot of plastic hooks that fit into the door. Not knowing where they all are makes it tough.

2. 16 year-old plastic breaks easily. I ended up JB Weld-ing a few things once I had the panel off. There were three tabs that are held by white clips that had broken. I could only fix one. The other two are just over the door speaker. I tried a couple of small screws there, but not much luck.

3. Working slowly preserved the plastic sheet. I used stencil adhesive to put it back on. The spray on stencil adhesive was pretty handy for this task. I may have skipped final tightening on a nut. When I go back in to check on it, we will see how forgiving this glue is. If the sheet does not survive the next removal, Plan B is cutting a polyethylene drop cloth to size.

4. There is more than one wrong way to put the regulator in, and try to get all the attachment sin place.

5. The inside of the door sheet metal is not flat. As tempting as it is to fit things together down where the large speaker opening is, you may not be able to. The lower slide channel has to go above that opening, and there is a lip that sticks in, making it hard to put together, then lift up.

6. Put the electric motor back on last. Once it is on the regulator, you have to use the switch to reposition anything. It worked better to be able to move things around to get all sliders in place, and put on the nut for the fixed point at the front of the rail, then lower to where I could get the motor on, and tighten down, then lift the mechanism into place to replace the five nuts.

7. Don't forget to tighten all nuts before you button it up. After I was done, and cooling off, I was thinking back though what finally worked, and I am not convinced I did final tightening on the fixed point on the front of the rail. Sigh. I attribute the loss of concentration to the length of time I was out in the sun. When I finally got everything into position, I just hurried too much.

8. 16 year-old sheet metal is still sharp. I picked up a few small nicks. I am pleased not to add any new scars. It also occurs to me that the scissor mechanism with an electric motor, and an auto-down feature could pretty easily lop a digit. I'll count avoiding this outcome as a victory.

Good luck!
Tom Lynch

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2016 E350 4matic wagon
2010 ML350 Bluetec
1995 E300D Gone, but not forgotten.

Thanks for the pointers, I've been putting off doing this job for best part of a year as I heard it's a real pain but will get 'round to it at some point. Mine still goes up and down but leaves a gap. I found that if I open the door and sandwich the glass between my palms I can pull it up the last 1/2" or so gap there is at the top and same to pull it and re-engage on the teeth to wind down, it's a bit ghetto but works for now...

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1993 320TE M104
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past:

1983 230E W123 M102
1994 E300D S124 OM606 (x2)
1967 250SE W108 M129
1972 280se 3.5 W108 M116
1980 280SE W116 M110
1980 350SE W116 M116
1992 300E W124 M103
1994 E280 W124 M104
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"music and women I cannot but give way to, whatever my business" -Pepys

One thing I did not mention:

I used a bunch of soft wood shims to wedge the window in place so that I could work without it falling down. It took three bundled up to fit the gap after the rubber strip came out with the door panel.

I usually had two sets in place to make sure things stayed put. I am not sure how, but the vertical slider came off its track at some point. When the regulator was out, I found that the glass would wobble fore and aft a good bit.

Regards,
Tom

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2016 E350 4matic wagon
2010 ML350 Bluetec
1995 E300D Gone, but not forgotten.

did your window exhibit any noise issues before it started failing? i just started noticing that my passenger window makes a soft noise like something is being activated in the door. almost like the electrics are engaged every 15seconds... i am not sure what it could be. don't want to thread cap, sorry.

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Grey '91 350SDL 214k Dad's car
Beige '81 240D 4 Speed 254k SOLD
Blue '82 300D 225k SOLD
White '95 E300D 46k SOLD
Blue '87 190D 2.5 Turbo 315k SOLD
Brown '80 240D 4 Speed 716k SOLD
Beige '80 300D N/A 119k SOLD
Blue '85 300D Model 186k T-Boned

I don't remember anything dramatic, but I have been living with the window stuck for a while. There had to have been some sort of a "pop". I just don't remember anything that grabbed my attention the way my Beetle did when I bounced over train tracks while lowering the window. I found quite a few threads from users with the same problem. You may find some of them have better accounts.

Actually, the information from those threads persuaded me to go ahead and get the regulator. Although it could have been an inexpensive slider, the number of times that driver's window regulators had welds that failed seemed to support the idea that the most used window just wears out the innards. It was a good guess.

Good luck!
Tom

__________________
2016 E350 4matic wagon
2010 ML350 Bluetec
1995 E300D Gone, but not forgotten.