Gap between Rubber Windshield Seal & Body

[pmajka]

The question is...Is this a problem or not? can this cause a leak or rust somewhere or not?

I have the same issue, same spot.

[RichMink76]

I left my trim off and had the same problem. I used some thick gauge wire in the corners where the gap was. I peeled up the rubber and put about 1 foot lengths at the corners in between the edge of the glass and the seal (not in the groove where the trim goes). Pretty much took care of the problem.

Rich

[KevinP73]

Originally posted by pmajka
The question is...Is this a problem or not? can this cause a leak or rust somewhere or not?

I have the same issue, same spot.

Yes it's a problem. This condition will allow water to seep into the interior and will promote rust forming in the corner of the window openings.

[lateapex911]

I have the same issue, and have done my own install, twice, and got it very close. Randy's and Kevins comments make toatal sense, I will go 'Adjust" with the alum trim. Thanks!

And yes, it WILL leak...I have shied away from rain driving for 15 years now...LOL.

[Jim Sims]

A properly installed windshield with a new OEM gasket and a clean good condition flange typically will not leak water into the interior of the car. In almost any installation water will get down to the lower flange area and pool on the OUTSIDE of the seal - it will not leak into the interior. It WILL rust bare metal that is exposed on the outside of the flange (knife and scraper scratches) and will do so even faster if road chemicals (salt) are added. When you see a rusty cowl near the windshield base it is highly likely the car was subjected to a windshield removal/replacement. Silicone rubber (silastic) sealants also seem to promote such rust.

[randywebb]

Yes - I'm concerned about the use of silicone -- it is hydrophilic to some degree.

Randy B. -- if I understand the procedure correctly; he will shape wood or something else fairly soft so it fits into the upper left corner (near the gap); then strike it fairly gently to distort the metal trim that one sees in the pic above and that will move the rubber seal over the approx. 2-3 mm that it needs.

(I say distort, although it maybe distorted in its current shape.)

Is that it?

[Randy Blaylock]

Exactly....

[1982911SCTarga]

Speaking from the experience of having replaced the windshield seal on my SC:

-- You might have too small a gap between the left and right trim sections where they meet at the top center of your windshield (the joint is covered by the center joining section). This might allow the seal to droop just enough such that it's not covering the left upper corner properly. As has been suggested, a very carefully placed knock in the corner might correct it. Or not, in which case ...

-- The windshield seal is not a terribly expensive item. Go back in and replace it. Take your time and get it correctly situated. These seals do shrink. You might say, "Oh but it's only a year old," however, how many years before that was it sitting in a parts warehouse coiled up and misshapen in its (possibly) leaky plastic bag.

In any case, I would stay away from silicone, dum dum or stuff like that. I had to clean all that crap out when I replaced my windshield seal and I wasn't a happy camper. You never know when you might have to go in and replace it again.

Windshield seal replacement is not a difficult job. There's tons of posts about this task.

Brian

[kwm]

Could we please see pics of your new paint job, whole car pics?

[Tom '74 911]

I tried to post earlier, but my internet connection went down.
I'm in the exact same boat as most everyone who's posted so far - I reinstalled my windshield w/new OEM seal last spring and had the same result. I ended up reinstalling my reinstall about 4 times and finally was able to center it just enough side-to-side and up-down to get the seal to barely, and I mean barely, cover the upper corners. Every few weeks I have to pry the lip back up as it's slipped down into the void. I was/am not too excited to squeeze a bunch of goop in the void for fear that it will just trap more water in there. I did some medium level rust repair at the lower corners of the frame when I had the glass out and fear for their condition long term.

I remember hearing at some point that there was an aftermarket seal available w/a bigger lip, but I wasn't able to locate it. After my experiance, I was almost motivated enough to try to manufacture and market one myself, but I know nothing about that sort of thing. . . and I'm already too busy as it is.

Randy's process, a few posts above sounds like the best idea I've heard so far. I had a lot of soapy water easing my install(s) so I think that it might be the ticket. I may have to try to lube up the groove where the glass is and see if I can get the corners to budge. One thing I learned was that it's easier to install the whole assembly too low than too high - thus creating the gaps at the upper corners.

Tom

[Randy Blaylock]

Installing a 911 windshield is a six step process;

1. Fool a friend into helping, having someone who can apply light pressure on the outside as you're pulling string makes it go much easier.

2. Prep the unibody windshield area, making sure to remove all goop, glue, whatever, and/or corrosion repair. Wax it up with a good car wax, this helps the seal slide in and over the flange.

3. Assembling the package. I like to throw a blanket on the roof, and lay the glass on it since the curve of the roof complements the glass well, and makes working easy. Place the rubber on to the glass, insert the aluminum support trim into it's place, making sure that the hook on it's back side grabs the rubber all the way around because it's nearly impossible to do this once the glass is in place, and run a string or something (I use small gauge safety wire since it never breaks) into the slot in the rubber gasket. Ready to go.

4. Lay the package in place. Starting with the bottom, slowly work the string out, making sure to roll the rubber lip over the metal flange. Work your way around from the bottom-center to one of the lower corners and stop. Go back to the bottom-center and go the other way, and continue around to the upper corner and stop. Do the other side. At this point, the upper edge is still sticking out a little, and you can get a feel for how well it's centered. It does not have to be exact. Finish it off if it's close enough. Believe it or not, over time the glass will shift by itself in the gasket after it's installed and find it's happy place, after driving a while, and the chassis flexes around. Again, it really helps to have someone apply light pressure on the outside with an open hand near the area where you're pulling string. So now the glass is installed. You are not done. Repeat, you are not done. Do not despair.

5. Now the trim ring needs to be tweaked to close up any gaps, the method I described earlier has worked for me very well over the years. It's up to you to decide how well you want the gasket to seal. And yes, no leaks. Leaks are not an eventuality. There is no "factory" specified shape to the aluminum trim piece. Remember, part of the beauty of these cars is that they're somewhat hand built, so there are variances in things. That's why there is a large rubber gasket, and if you placed the glass without a gasket in the opening in the unibody, it will fall in, the clearance is that much. The glass contributes nothing to structural rigidity or roll over protection, unlike later cars. The glass simply floats in it's gasket in the hole in the unibody. It will even come out by itself with no assistance from you if you stop quickly enough, just ask Jack. Don't ask me how I know this.

6. Drink beer.

[randywebb]

Thanks. The glass has been in the car about 5 months or so.

I'll tell the painter to call his glass guy up and if they want to try Randy Blaylock's procedure (at their risk) or if they want to take it out and put it in again however many times it takes them to get it right...

I assume that the tapping procedure will still work after 5 months (i.e. it does not rely on lubricated glass, rubber, or metal to work) ...??



kwm - I have a thread for you:
Yet Another Boring Hot Rod Rgruppe Car - Part V, Exterior & Paint

- unfortunately have never had time to post the complete stories on the hot rod motor, trans, susp. & brakes - it's mostly been done by others at this point anyway...

[john walker's workshop]

the seals i get from worldpac are supposedly the wider lip variety. if the corners still fall in, a blob of strip caulk, aka dum-dum, wadded up in the corners will support the lip. you see that all the time when you remove windshields. you can work it in there after the install by pulling the lip back and pushing the caulk in with a screwdriver tip.

[Randy Blaylock]

Taking it in and out a hundred times will not solve the issue. The aluminum trim simply needs to be fitted. It's not a risky proposition at all if the forces are kept parallel to the surface of the glass, and it's about a 5 minute process. This is probably why the trim is comprised of two pieces with a longish coupler at the top and bottom, rather than a continuous piece, so it can be expanded as necessary. I'm surprised a professional installer doesn't know this. Yes, it can be done anytime, no lube necessary. I've done it to 30 year old cars with original seals and glass.

No disrespect intended JW, in my experience extra sealants are simply unnecessary unless there is a corrosion porosity component on the surface of the windshield frame that prevents the rubber seal from making good contact. In that case, all bets are off. But if the rubber seal lip lays firmly on the frame, and contacts the glass firmly, there is simply no route for water to enter.

[bigchillcar]

so, if i get the gist of this, the act of spreading the metal trim (in particular, beneath the coupler) spreads the seal as far as necessary. is anything needed between the metal pieces to hold them spread once this is done? picturing a gap that now needs to be filled by something that will be covered by the coupler..a 'nail with the head cut off' for lack of a better example..
ryan

[Randy Blaylock]

There will be a gap between the ends, of varying widths, depending upon the final shape needed to get the rubber seal outer lip covering all of the windshield opening. The coupler acts as an alignment device, as well as being a cosmetic cover for the gap. For sure the ends will not be in contact.

You're not really moving the trim piece much, more just helping the rubber seal itself assume the shape of a fairly tight radius in the corners, something it's not likely to do on it's own, as evidenced by the typical gaps that many seem to be experiencing.

[1982911SCTarga]

Ryan, I would have to go and look it up, but I think the Porsche workshop manual specs a starting dimension for the space between the top and bottom windshield trim sections at the center. Of course, the workshop manual also suggests using the factory's windshield fixture (a steel mock-up frame) to check the overall dimensions and correctness of the body's windshield opening before putting the windshield back in. John Walker, do you have one of those?

As Randy Blaylock says, with one person inside roping, the second person can slap and move the windshield around as it's being roped in. This isn't rocket science -- however much we want to intellectualize and mythologize things related to our marvelous cars.

I'm also with Randy on saying no to dum dum and other foreign materials. No leaks from mine. But, hey, I've got a Targa so I've got plenty of other places to worry about leaks.

Brian

[john walker's workshop]

i'm not talking sealants, just a bit of support in the corners to keep the lip from falling in. i never use sealants on my glass installs.

[Jim Sims]

"No one mentioned the dum dum packed into the corners to help back fill the void." ????

In the ~fifth reply: "A compound (sold for this purpose by 3M) can be used to fill the cavity and keep the gasket pushed out."

Using the term "dum dum" for the filler material to add to the body at windshield and rear glass corner areas (my '76 came from the factory with filler in all the lower corners, front and back) only produced dumb stares at auto supply stores and dealerships. What you want is 3M Seam Sealer Caulking Strip (part number 08578). It is available at NAPA (although they may have to order it in overnight from their warehouse). The NAPA Part number is MMM08578 and they charge $13.99 a box; a box is plenty to install windshield and rear
glass.

[Zeke]

Originally posted by Jim Sims
"No one mentioned the dum dum packed into the corners to help back fill the void." ????

In the ~fifth reply: "A compound (sold for this purpose by 3M) can be used to fill the cavity and keep the gasket pushed out."

Using the term "dum dum" for the filler material to add to the body at windshield and rear glass corner areas (my '76 came from the factory with filler in all the lower corners, front and back) only produced dumb stares at auto supply stores and dealerships. What you want is 3M Seam Sealer Caulking Strip (part number 08578). It is available at NAPA (although they may have to order it in overnight from their warehouse). The NAPA Part number is MMM08578 and they charge $13.99 a box; a box is plenty to install windshield and rear
glass.

Sorry, dude. I'll try to pay closer attention.