W123 coupe window adjustment - PeachParts Mercedes-Benz Forum

JHZR2 · #1 03-11-2012, 05:58 PM

Can someone make it real clear how the front windows are supposed to align do as to allow proper sealing and operation?

I'm seriously about to sell my coupe I'm so disgusted by the stupid front d/s window.

It either snags on the front corner at the top, or the rear edge where the two weatherstrips come together.

No matter what I do, I can't get them to work proper.

To add insult to injury, I had pulled the front triangle to replace the rubber on it, and when I have it adjusted so that it is properly aligned to have "light pressure" on the door seal, per the FSM, and then I roll the window up to be properly flush, the motor has to strain excessively and both the triangle and sheet metal holding the regulator each twist quite a bit to get the window up. I recognize that it is "new" rubber, but it has been mated to the window for over six months now, and is still excessively tight. Makes me fear that more is wrong.

Can anyone at least help me with a good understanding of the adjustment parameters, and how they effect one another? I have a paper FSM, I'm doing the adjustments and just not getting anywhere.

I'm especially interested in the Upper stop angle adjusters in FSM 72-195, as I can see that tightening them in different spots has varied effects, but there is no positive engagement and no good explanation of how they should be aligned and set.

I haven't had a lot of time to spend on this, but when I waste two hours each of my and my wife's time trying to fix this, and get nowhere, it really makes me insane.

Thanks.

JHZR2 · #2 03-13-2012, 04:05 AM

Can anyone comment on how much the triangle that is the mirror and front window track should flex when putting the window all the way up?

Could any coupe owners with recent window rubber post a pic of their window in the up position in terms of that front track at the very top?

Thanks!

Yak · #3 03-13-2012, 08:12 PM

Having sold mine, it's tough to help. Have you looked at adjusting the stop screw to affect the binding problem? Last step in 72-185.

How's your door alignment? Are the window scrapers in place and in good shape? I found the rear window needed the scrapers in place to have good inward/outward alignment.

JHZR2 · #4 03-13-2012, 08:54 PM

My issue isn't inward outward alignment as mush as angle of the window to properly go around the door gaskets per the FSM. Stops are in fine places. The biggest issue is that I can't get a good grasp of what the tilt angle adjustment screws shown in the FSM do, as there is no positive engagement of anything, and when loose, they can just be slid wherever. So, it is tough to see how to best adjust them.

I think my door droops slightly, I've played with the striker and it closes when closed hard, to get most of the window nicely under the rubber and everything well aligned.

Yak · #5 03-13-2012, 10:05 PM

Going from the book and memory:

The two screws in the pic for the triangle on pg 72.4-195/2 adjust the position of the triangle. I assume the triangle has slots or oversize holes that let it get moved up/down and fore/aft. I think you'd adjust this so it fits against the frame of the door. Think of this as the cornerstone. You need to have it good for angle (close to the frame) height (too low and it'll stop the window before the top seals; too high with correct angle it'll hit the frame when closing the door) and fore/aft (similar problems with height adjust: aft it'll stop the glass; forward it'll hit the frame).

The other two angle stop screws set the angle. I think just for the regulator contact. There's a front upper stop and a rear upper stop. With the rear one fixed, sliding the front one up should let the front upper corner go higher. This would push the rear upper corner slightly rearwards and cause the front top to impact the rubber first, and possibly create a gap and the front rear. I think these stops hit the regulator. So when you adjust these you are adjusting the position upper stop position of the regulator relative to the door. You can also adjust the position of the glass relative to the regulator. There also appears to be a third upper limit screw that isn't mentioned until the last step or so. It may be near the position where the manual crank handle would be?

If the glass is really torquing the rubber and the triangle, maybe lower this stop screw?

Or lower this stop screw and the two upper angle stop screws all the way down. In theory, this might stop the window a quarter inch or so away from the rubber, then increment them upwards until you get the contact you want. Basically start at one extreme and start working towards a satisfactory result.

Then there are three bolts that hold the glass to the regulator.

You could, possibly, have the upper stops adjusted perfectly in height and angle and the window mates to the top perfectly, but has a consistent gap at the front. So you'd need to adjust the glass relative to the regulator to shift the glass forward but not affect the stops. Maybe use these to make fine tune adjustments not possible with the angle-regulator stops.

Maybe some pics of the problems you're having? Like I said, memory and the book, so I could be way off base.

JHZR2 · #6 03-14-2012, 12:34 PM

Quote:

Originally Posted by Yak

Going from the book and memory:

The two screws in the pic for the triangle on pg 72.4-195/2 adjust the position of the triangle. I assume the triangle has slots or oversize holes that let it get moved up/down and fore/aft. I think you'd adjust this so it fits against the frame of the door. Think of this as the cornerstone. You need to have it good for angle (close to the frame) height (too low and it'll stop the window before the top seals; too high with correct angle it'll hit the frame when closing the door) and fore/aft (similar problems with height adjust: aft it'll stop the glass; forward it'll hit the frame).

Yes, exactly. The holes are elongated to allow for forward/aft movement. The point in the FSM is to adjust these so that the triangle makes light pressure on the main weatherstrip that it sits against.

Quote:

The other two angle stop screws set the angle. I think just for the regulator contact. There's a front upper stop and a rear upper stop. With the rear one fixed, sliding the front one up should let the front upper corner go higher. This would push the rear upper corner slightly rearwards and cause the front top to impact the rubber first, and possibly create a gap and the front rear. I think these stops hit the regulator. So when you adjust these you are adjusting the position upper stop position of the regulator relative to the door. You can also adjust the position of the glass relative to the regulator. There also appears to be a third upper limit screw that isn't mentioned until the last step or so. It may be near the position where the manual crank handle would be?

If the glass is really torquing the rubber and the triangle, maybe lower this stop screw?

The next step is to adjust the window so that it is aligned with the front triangle. This is where the problem starts. The rubber slot that the window slides into on the triangle is tight enough that the entire mirror/metal/door assembly has to shift under the torque. Actually the regulator itself torques the door sheetmetal due to difficulty getting the window up far enough to sit in the correct, aligned position. If I lowered the stop screw, I would not get proper alignment with the front triangle. There is no way to raise/lower its height, and it is the one thing that is a straightforward adjustment (so I think).

Quote:

Or lower this stop screw and the two upper angle stop screws all the way down. In theory, this might stop the window a quarter inch or so away from the rubber, then increment them upwards until you get the contact you want. Basically start at one extreme and start working towards a satisfactory result.

I completely believe that the upper stop IS in the correct position, because though the angles are off, I know from playing with the window over the last few years that if I lower the window even the slightest, I get wind noise. Its position in all but the very top front corner is perfect per the images in the FSM and known operation, so I'm hesitant to move it.

Quote:

Then there are three bolts that hold the glass to the regulator.

You could, possibly, have the upper stops adjusted perfectly in height and angle and the window mates to the top perfectly, but has a consistent gap at the front. So you'd need to adjust the glass relative to the regulator to shift the glass forward but not affect the stops. Maybe use these to make fine tune adjustments not possible with the angle-regulator stops.

Maybe some pics of the problems you're having? Like I said, memory and the book, so I could be way off base.

If I shifted the glass forward, Id have greater issues because of the fact that the top front corner is already the one not going in properly. If I shifted back slightly, Id no longer have the slight pressure on the triangle against the weatherstrip.

I do have to wonder if I shifted the glass back a bit but left the triangle as is would put less glass contact against the track in the triangle piece, reducing friction and helping there.

Does a rubber track like the window slides in on the triangle piece need some lubrication? If so, what?

Thanks again!!!

ngarover · #7 03-14-2012, 01:13 PM

Dont know if this will help you or not, but here is a video I shot when I did mine.

300CD_window.MP4 - YouTube

Yak · #8 03-14-2012, 07:00 PM

Quote:

Originally Posted by JHZR2

Yes, exactly. The holes are elongated to allow for forward/aft movement. The point in the FSM is to adjust these so that the triangle makes light pressure on the main weatherstrip that it sits against.

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Does a rubber track like the window slides in on the triangle piece need some lubrication? If so, what?

Thanks again!!!

I remember "window lube" kits that had a spray and a powder in Germany. I haven't seen them in the US. I've heard of people using talcum, but I think that'd messy.

Liquid Wrench Dry Lube was recommended on some other sites. It does sound like friction is an issue.

JHZR2 · #9 03-15-2012, 03:52 AM

Quote:

Originally Posted by ngarover

Dont know if this will help you or not, but here is a video I shot when I did mine.

300CD_window.MP4 - YouTube

Nice video! You stated that you loosened all the screws at once and then watched the window go up and down. But what did you watch for?

More importantly, how did you decide where to tighten up the stops? My issue is that the upper set of angle stops are just loose and sitting there. When you have the window situated, how do you know where to align those upper angle stops in their slots? You could really arbitrarily tighten them down at any point in the slot and it will close down. There is no positive feedback that the stop is actually hard against something, and you really cannot see either...

bmwpowere36m3 · #10 03-15-2012, 07:26 PM

Quote:

Originally Posted by JHZR2

Nice video! You stated that you loosened all the screws at once and then watched the window go up and down. But what did you watch for?

More importantly, how did you decide where to tighten up the stops? My issue is that the upper set of angle stops are just loose and sitting there. When you have the window situated, how do you know where to align those upper angle stops in their slots? You could really arbitrarily tighten them down at any point in the slot and it will close down. There is no positive feedback that the stop is actually hard against something, and you really cannot see either...

The further "down" the stops are in their slots, the earlier the window will stop (i.e. sit low, when fully raised). If you set the window stops too high, the window will get caught on the weatherstripping edge or cause the door to be difficult to close. If you set it too low, then it wont fully seal.

You need to adjust both stops so the window stops at the right height and doesn't get cocked. When the window gets cocked it bends the window lift mechanism. Thus causing the door/triangle to bow and put additional strain on the mechanism.

It takes some playing around with and many adjustments to get just right. Per the FSM:

Adjust triangle so it touches the weatherstripping lightly at front edge (fore/aft)
Loosen both stops and lift window till its front edge lines up with the triangle (i.e. the angle \)
Adjust angle of upper edge of window so it parallel to weatherstripping
Adjust preload of window against weatherstripping
Adjust rear window track so rear window edge is parallel with quarter window gasket
Finally adjust rear window guide wedge so its in contact with the window's rear edge

Obviously you'll need to go back and make slight tweaks so it all works.

StaggerLee · #11 03-15-2012, 07:32 PM

Try some dish soap where the window slides.

ngarover · #12 03-16-2012, 08:03 AM

Quote:

Originally Posted by JHZR2

Nice video! You stated that you loosened all the screws at once and then watched the window go up and down. But what did you watch for?

More importantly, how did you decide where to tighten up the stops? My issue is that the upper set of angle stops are just loose and sitting there. When you have the window situated, how do you know where to align those upper angle stops in their slots? You could really arbitrarily tighten them down at any point in the slot and it will close down. There is no positive feedback that the stop is actually hard against something, and you really cannot see either...

It was trial and error, but only took about 10 minutes. basically, operated the window, first made sure it was opening and closing straight, then closed the door and did it again, and again tweaking the bolts enough to hold the setting in place.

Once you start to do it, it will all make sense. last thing I did was worry about the stop. got everything else correct first then played with the height of the window, which I set to just catch the lip of the rubber. Sealed up tight after that.

JHZR2 · #13 03-23-2012, 11:39 PM

I nearly was about to put a mint cd with funky window up for sale. Followed the FSM a few ones without success. I'd often get it >50% right, but then tighten one more thing and it would go completely out of whack. Usually either the front leading edge top or the rear top edge would catch by the time I got things running.

Played with all the adjustments, no luck. The front could be perfect, but the rear would raise an extra amount at the end throwing everything off. It is almost as if the rear stop was not there engaging, though there was some Position for it each time.

I think I'm starting to get there. I think I may have it right, so long as something else isn't showing up next... Just accidentally hit everything right so think it was luck. Wish there was a better explained process. And who knows, I could hear wind and have to go back to sauare one..

JHZR2 · #14 06-30-2012, 02:57 PM

Still no luck. It seems great and then some other aspect comes to pass when I close it.

I'm pretty certain that none of the stops are actually capable of physically stopping the window in its travel. No matter how or where I clamp them down, they will be violated under some condition. In fact, I don't know which are actually "stops" anymore. They just don't work, and none of the FSM adjustments are helping. I've even loosened the window on the regulator to adjust it, itself without any luck. Make it look right one way, something else is wrong, and on and on and on.

This is so frustrating. I haven't driven the car in a year because I am disgusted with this. And no idea if in the end the rear regulators, cleaned and lubed, will actually be functional. Heck, I do t remember how I took all this stuff apart to be able to put it all together. What a mess.

I may well sell this car, I'm so sick of this. It is the only thing wrong.

79Mercy · #15 06-30-2012, 03:33 PM

Maybe your regulator is bent, i had barely any trouble adjusting the window in my 280CE just following the directions.