69 Coupe Door Glass Adjustment...

[Greg L.]

I'm having some issues with trying to properly adjust each door glass and was hoping someone might have some suggestions to help me along. The car has power windows and I'm using the AIM & GM Manual, the glass is the original glass and the weather strip is from Corvette Rubber Company.

My issue with the drivers side is that it seems like the glass is "dragging" on the A pillar strip as the window is powered up. This leaves a noticeable gap between the front upper corner of the glass and the T-top side seal, also the aft vertical edge of the glass is no longer parallel with the B pillar when it's up. The glass actually rotates counter clockwise as it's dragging against the A pillar weather strip. If I crack the door open and power the glass up then all is good and it fits fine when I close the door. Then if I adjust the glass clockwise to compensate for it's movement against the A pillar it seals better all around when powered up with the door closed however the upper aft corner of the glass then contacts the B pillar and T-top latch adjustment plate when I open and close the door so that is not a solution either.

I can't seem to find a happy medium here, either there is a gap on the top front edge of the glass or the top aft corner is hitting the B pillar and T-top latch adjustment plate. With the glass a couple inches down from the up-stops it does seem sort of "loose" like you can grab it and rotate it back and forth a bit but I'm not sure if that is acceptable or not.

Even though I've had both door mechanisms out and inspected them and felt that everything was okay I thought I'd try to adjust the passenger side. My theory is that if something is worn that the passenger side should have far less wear so I might get lucky. Well that side seems to have adjusted up a lot better(not perfect yet but much better) so now I'm wondering if some things are too badly worn on the drivers side to allow for proper adjustment.

Does anyone have any ideas here for me? Like I say the drivers side components seemed okay when I had it all apart but maybe I missed something or didn't realize how tight it has to be... Are there any "common wear" items that I should have replaced? I really didn't want to replace any original parts with repop parts unless I have too.

Also are there any good products out there to soften rubber to maybe help reduce the "dragging" that I'm having. I remember a GM product called Silicone Emulsion years ago that was used to preserve weather strip. Would that be something to try or is there a better product these days?

Sorry for the long winded story but I hope it better explains my issue here. Thanks guys.

[David H.]

Re: 69 Coupe Door Glass Adjustment...

Greg,

I don't have a specific answer to your questions, however, the link below might help especially with your worn parts question. There are several other articles on the CC tech board that might be applicable as well.

http://tech.corvettecentral.com/2011/04/1968-82-corvette-door-glass-service/

Dave

[Steve G.]

Re: 69 Coupe Door Glass Adjustment...

When I assembled the doors and windows in the 69 I am just finishing I followed the AIM's instructions in terms of sequence. I was amazed at how easy it was. I don't have the manual in front of me at the moment, but here are a couple of thoughts.

Do your adjustment with the windows up and check them by closing the door slowly with the window up. You don't actually close the door right to the latch, just bring the glass up to the weather strip and check it all around. This gives you the mark of where the glass is in relation to the weatherstrip without the distortion that may be happening when you attempt to power the window up. If the glass is running up parallel to the pillars as it should, but is too far forward it will bind and pull itself off square. Doing it this way you can get the edge of the glass sitting exactly in the dimension the AIM gives you.

Once you have the glass squared up and adjusted to the opening run it down and check it for proper operation.

Steve g

[Greg L.]

Re: 69 Coupe Door Glass Adjustment...

Thanks Dave,
I also used that article when the AIM and Service Manual "failed" me but I only read the adjusting portion of it.

I re-read the article and took this from it "Check the window regulator rollers for wear. They should fit tight on their support shaft with no perceptible play. There are three rollers affixed to the window regulator: two are located in the horizontal lift track and the third is in a horizontal tilt adjustment track. Loose window regulator rollers in either track allow the glass to tilt. ALL rollers do fit nice and tight on their support shaft and I thought that that was all that needed to be checked. I realise that if the plastic guides are too loose in their tracks that it will cause undesirable movement but since the window functioned without any obvious issues before it was taken apart I figured that any wear was negligible but maybe I'm wrong on that. Now I'm wondering if any previous wear is somehow being magnified because there in now more resistance (drag) against the new A pillar weather strip as compared to the old dry ones.

So now I have to ask...just how loose is too loose when you are comparing roller to track wear. Is there a dimension to check roller wear or I wonder if I should just replace them all and try again? Could the regulator itself cause my problem or should I just concentrate on the 3 for the horizontal tracks?

[Steve G.]

Re: 69 Coupe Door Glass Adjustment...

So with the window powered up all the way against it's vertical travel stops with the door open the door closes properly, glass folds into the frt strip as it should and all dimensions are as per the AIM?

And when you watch the glass (door open) come up against the stops you don't see the glass "straighten up" when it hits the stops, as in the stops are correcting the misalignment of the glass?

And if you lower it off the stops and grab the back edge of the glass and rock it up and down you have how much movement?

Steve

[Greg L.]

Re: 69 Coupe Door Glass Adjustment...

Hi Steve,

"So with the window powered up all the way against it's vertical travel stops with the door open the door closes properly, glass folds into the front strip as it should and all dimensions are as per the AIM?"
I would say yes however it's hard to tell if the glass folds into the front strip as far as it should. I can say that this edge of the glass is not visible when in the strip groove so it does look correct.

"And when you watch the glass (door open) come up against the stops you don't see the glass "straighten up" when it hits the stops, as in the stops are correcting the misalignment of the glass?"
That is correct. I set the upper stops so that the top of the glass is parallel with the T-Top weather strip. That much I have been able to achieve.

"And if you lower it off the stops and grab the back edge of the glass and rock it up and down you have how much movement?"
This is hard to tell but it looks like I have about 1/4" up and down play at the front and at the rear. I can also pull the glass evenly up and down almost the same amount(maybe 3/16") but that feels like it's more in the regulator gearing so I don't think that would affect the "tilting" that I'm experiencing when the glass is almost fully up.
I'm not sure if this next clue is anything or not but I noticed that if the glass is all the way up with the door open and then I close it to get the proper seal, when I power the glass down the front edge drops first, then the back side comes down.....

[Steve G.]

Re: 69 Coupe Door Glass Adjustment...

Hi Steve,

"So with the window powered up all the way against it's vertical travel stops with the door open the door closes properly, glass folds into the front strip as it should and all dimensions are as per the AIM?"
I would say yes however it's hard to tell if the glass folds into the front strip as far as it should. I can say that this edge of the glass is not visible when in the strip groove so it does look correct.The glass should be barely behind that outer lip. I think the AIM gives it something like a 1/16th". Has to just make it behind it.

"And when you watch the glass (door open) come up against the stops you don't see the glass "straighten up" when it hits the stops, as in the stops are correcting the misalignment of the glass?"
That is correct. I set the upper stops so that the top of the glass is parallel with the T-Top weather strip. That much I have been able to achieve. This may be part of the problem. The track adjustments should be keeping the glass square. It should be adjusted so that it rises parallel to the rear pillar and top of opening. If you were able to stop it at it's appropriate height without the stops in place it should be aligned. Easier to do with manual windows. You would then slide both stops down at that point. IOW, the stops shouldn't be causing anything to come into alignment, they should just be providing the stop for the already aligned mechanism.

"And if you lower it off the stops and grab the back edge of the glass and rock it up and down you have how much movement?"
This is hard to tell but it looks like I have about 1/4" up and down play at the front and at the rear. I can also pull the glass evenly up and down almost the same amount(maybe 3/16") but that feels like it's more in the regulator gearing so I don't think that would affect the "tilting" that I'm experiencing when the glass is almost fully up.
I'm not sure if this next clue is anything or not but I noticed that if the glass is all the way up with the door open and then I close it to get the proper seal, when I power the glass down the front edge drops first, then the back side comes down..... While 0 play in the mechanism is ideal, you should be able to adjust the window so that it goes up and down without the issue you describe even with a considerable amount of play in the mechanism. That's one of the reasons the adjustment is there.

I suspect that the frt edge of the glass needs to be raised and perhaps the entire glass moved rearward once adjusted to be traveling up parallel to the rear pillar. The rear of the glass may be sticking because it is traveling higher than it is supposed to and binding it up, while the front is not high enough.

I would loosen the stops and lower the glass about 1/2" from the top of it's current travel. I believe it's the track with the single roller that levels the glass. Adjust that so that the top is parallel with the top w/s. Now move the glass rearward so that it is maybe not quite falling behind the frt strip lip. Run the glass up and see how it works. If it seems okay move the glass forward until it is just behind the lip. Run it up to it's proper height and drop the stops down and tighten them.

Steve