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My 68 has had the windshield replaced and I’m not happy with the gap at the top of the windshield on the passenger side. Is the only fix for this going to be re installing the windshield? The fit in all the other areas is good. I’m surprised the is no type of seal as water would go directly behind the trim. Thank you.
The gap is there because the installer did not set the glass at the right height and you are correct the only cure is to remove the glass and reset it to the proper height. There is a problem with removal though, in the center of the glass on the bottom the sealant is run in a straight line and the glass in the center is lower and when pushing up on the glass for removal it pivots off the lowest portion above the sealant line and it cracks the glass. T
Last edited by terrys6t8roadster; 01-27-2019 at 06:53 AM.
I agree
It is hard to see the pics, but the glass needs to be reset. You can get the glass out, just use piano wire to cut the seal. I installed my own WS. Yes a pain and messy but it can be done. There are several excellent write ups and videos on the web
Thanks guys. Pretty much what I figured. I will try to cut it out and reuse the glass if I can, if it breaks then I’ll just get another. That gap will drive me nuts if I do not fix it.
I installed a new windshield myself in the garage on my 69. I measured and the old glass was about .275" thick and the new ones are about .205". GM used a 5/16" damming strip around the windshield to hold it out so with the thinner glass I had to use a 3/8" strip under the glass to get the spacing between the glass and trim right. It doesn't look like they used anything in your pic let alone a slightly thicker strip. I would complain but then I wouldn't want the installer to touch my car again. This is how the gaps on my 69 turned out.
I did get the glass out without breaking it. There was no damming strip at all and the glass was sunk significantly in that corner. That is some gooey crap.
Glad to hear you got it out without breaking it. I also used the PGW Solex replacement glass so make sure you get the proper size damming strip. That PGW glass measured .205 thick while the original was .275. With .070" thinner glass you will probably need a 3/8" thick strip instead of the stock 5/16". Install it a couple of times and check the trim for fit before you run the sealer and drop it in. Mark a point on the glass and the same on the frame, top and bottom so when the adhesive is applied you can drop the glass right in on those marks so you don't have to try and shift it to center after. The damming strip I used was 1/4" wide and 3/8" tall. I believe the stuff below is what I used. https://www.ebay.com/itm/CRL-Single-...-/172180454238
Last edited by CanadaGrant; 02-06-2019 at 06:08 PM.
Glad to hear you got it out without breaking it. I also used the PGW Solex replacement glass so make sure you get the proper size damming strip. That PGW glass measured .205 thick while the original was .275. With .070" thinner glass you will probably need a 3/8" thick strip instead of the stock 5/16". Install it a couple of times and check the trim for fit before you run the sealer and drop it in. Mark a point on the glass and the same on the frame, top and bottom so when the adhesive is applied you can drop the glass right in on those marks so you don't have to try and shift it to center after. The damming strip I used was 1/4" wide and 3/8" tall. I believe the stuff below is what I used. https://www.ebay.com/itm/CRL-Single-...-/172180454238
Thanks for the tip. That is the exact damming strip I bought. Hopefully it will be here tomorrow and I can get the glass back in Friday.
One other thing I forgot to mention is that once the glass dropped in, install the 2 A-pillar stainless pieces just to make sure you have the exact glass height you want. You can push down on the glass to make it perfect but it's just to check. You don't have to worry about the horizontal top stainless as it rides on the A-pillar trim in the corners so will be the same. It all sounds kind of scary but the work isn't in the install but in the planning. Also, on your 68 the bottom glass support is offset to the passenger side a bit so to prevent the glass from sagging on the drivers side while setting I installed a couple of rubber or foam spacers at the top corners to keep the glass in the same position until it set up. You can see them (white) at each top corner molding.
Last edited by CanadaGrant; 02-07-2019 at 12:00 AM.
so grant, i have put alot of windshields in camaros chevelles and my 65 roadster. i have never heard of the damming strip? i have only used the factory style buttle tape on my installs.. is the damming strip something you need to use when you use a urethane tube sealer that is prone too slide until it sets up? i am also getting ready to put glass in my 68, and want to make sure i have everything. thanks troy
I don’t think butyl tape is the factory method. Regardless, my windshield had been installed with butyl tape and the glass was set too deep so the trim did not fit properly. The damming strip ensures the glass sets at the correct height as well as keeps the glue from flowing in. I’m not sure if the factory used a damming strip with their install.
68L71 is correct. There is a diagram in the factory AIM that shows this. They used a damming strip and some rubber spacers (there were 4 under my orig. 69 glass) to get the distance from the frame to glass correct. With a new foam type damming strip you don't need spacers anymore. Just the right thickness strip. It also gives a smooth edge around the inside of the windshield visible from inside the car or through the glass. Then, they used this stuff called Thiokol Sealer which is not used anymore because it didn't hold well in a crash and windshields could pop right out. It was used around the outside of the damming strip to hold the glass down and seal it. I believe the factory strip was 5/16" thick but aftermarket glass is thinner than original requiring a little thicker strip in most cases. Along the top and sides you have to run the damming strip no more than 1/4" from the glass edge or it will be too far in. Best idea is to trial fit the glass with some 3/8" spacers or whatever you're using and mark the inside edge of the frame on the glass with a marker so you get your damming strip just outside those marks. You don't want the strip too far in and ending up in the car but you need at least 3/16" outside the strip for your sealer. With aftermarket glass there is no room for error along the A-pillars. Basically, the damming strip just provides equal spacing from the frame, something to run your sealer up against, and is for appearance purposes or you would be looking at a big bead of dripping or uneven sealer from inside the car.
My 69 had the original glass and the Thiokol was so weak that after the trim was off you could just push the glass out. I replaced it because the glass was delaminating around the upper corners and down the sides by the A-pliiars.
Last edited by CanadaGrant; 02-09-2019 at 10:08 AM.
When sealing along the upper windshield stainless piece with the top header trim and in the corners with the A-pillar stainless GM used a kind of gray putty type sealer. The stuff below looks exactly like it and seals perfectly. If you look at the pic in post 5 you will see.
When sealing along the upper windshield stainless piece with the top header trim and in the corners with the A-pillar stainless GM used a kind of gray putty type sealer. The stuff below looks exactly like it and seals perfectly. If you look at the pic in post 5 you will see.
Sweet thank you. As I was working today I wondered what I was going to use in the corners. The install went well. The only issue I have is along the sides you can see the damming strip through the glass. There was not enough width of the glass to get it under the stainless side trim.
You can see the damming strip along the A-pillar from outside the car, running down the pillar but the inside of the strip should be fairly even with the inside of the frame behind. That's why it's there. It's for a clean line as well as spacing but your last sentence has me puzzled. Are you saying the outer edge of the glass itself is not covered by the stainless side trim or are you saying that you can see part or most of of the damming strip just outside the stainless? I hope the answer is door number 2 as the edge of the glass itself should be really close at the bottom of the stainless but not visible. Once you push the A-pillar stainless down into place, push it in and tighten it down the bottom edge of the glass will be close but shouldn't be visible.
Last edited by CanadaGrant; 02-09-2019 at 10:27 AM.
You can see the damming strip along the A-pillar from outside the car, running down the pillar but the inside of the strip should be fairly even with the inside of the frame behind.
This is exactly how it is, so I guess all is good. In my last sentence I meant enough width to have the damming strip be under the stainless and not visible. On the inside the strip is even with the frame.
That should be correct then. Don't forget due to reduced glass thickness you moved the glass out an extra1/16" to get your gaps correct so it reduces the amount or width of glass under the a-pillar stainless slightly and there isn't much room for error. Sounds like you got it right. How did your stainless gaps turn out?
Last edited by CanadaGrant; 02-09-2019 at 10:18 AM.
The gaps turned out ok. The sides are perfect but the top piece is not 100% perfect. Maybe the piece is bent a bit. Installed it about 4-5 times and got it as good as I can. Much much better than in was previously.
That looks really good! Nothing like before. I see the spot you mean and it's the stainless. If you ever have that top piece off again just squeeze it together with the vertical back edge of the trim and that tiny gap will disappear. Sometimes they get bent upwards slightly like that from removing the trim so squeezing it together just with your hands works. I like the bottom pic. Nice job!
Last edited by CanadaGrant; 02-09-2019 at 04:08 PM.
Every car show I attend, whether it be an auction or a local car cruise, I tend to look at the windshield gap. And many C3 Corvettes have had their windshields replaced incorrectly. Good job on correcting yours. I dont think you can get 100% on anything on these cars, a happy compromise works for me.
01-26-2019, 03:56 PM
1968 replacement windshield fit
68L71 is correct. There is a diagram in the factory AIM that shows this. They used a damming strip and some rubber spacers (there were 4 under my orig. 69 glass) to get the distance from the frame to glass correct. With a new foam type damming strip you don't need spacers anymore. Just the right thickness strip. It also gives a smooth edge around the inside of the windshield visible from inside the car or through the glass. Then, they used this stuff called Thiokol Sealer which is not used anymore because it didn't hold well in a crash and windshields could pop right out. It was used around the outside of the damming strip to hold the glass down and seal it. I believe the factory strip was 5/16" thick but aftermarket glass is thinner than original requiring a little thicker strip in most cases. Along the top and sides you have to run the damming strip no more than 1/4" from the glass edge or it will be too far in. Best idea is to trial fit the glass with some 3/8" spacers or whatever you're using and mark the inside edge of the frame on the glass with a marker so you get your damming strip just outside those marks. You don't want the strip too far in and ending up in the car but you need at least 3/16" outside the strip for your sealer. With aftermarket glass there is no room for error along the A-pillars. Basically, the damming strip just provides equal spacing from the frame, something to run your sealer up against, and is for appearance purposes or you would be looking at a big bead of dripping or uneven sealer from inside the car.
