I noticed that the windows are raised about a 1/4 inch off the track on top of the sealant . How thick is this stuff , and will the window sink down any ? Do I need a thicker bead to accommodate this ?

 

There are some good instructional videos on YouTube to explain the process. The correct caulking tube cut is essential to put the correct "peak" in the bead. If you are installing a rear window in a fastback style Cutlass/442 you will need something to apply pressure to hold the sides (or at least one side) down while the caulking sets. This is due to the curvature of the body vs the straight tendency of the glass across the width of the body. You will understand what I mean when you dry fit the glass.

 

If you are saying that the thickness of the sealant between the pinchweld and the glass is about 1/4", that's about right. The surface of the pinchweld isn't a perfectly smooth surface, so this allows manufacturing tolerances and sheet metal overlaps to be accommodated. The factory sealant was urethane in a tube. I've also used butyl tape. Either way works.

 

Thanks Joe for your time and effort to help me out with this .

 

Butyl tape is O.K. To use for this method, however due to the imperfections of the pinch weld it would be wise to back fill with 3m after seal caulk..This falls into the imperfections where butyl tape does not to completely fill a possible gap and keep water out.. After seal cures to a flexible material and is compatible with butyl rolls and M-seal. Urethane is easier for Pros to use but sometimes messy. Hope this helps

Sean

 

Cool , thanks

 

I've installed a number of windshields with butyl tape and I can't say that I've ever done this or had a leak. I just ensure that the tape is warmed in the sun and push down on the edges of the glass to force it into place. The tape I've used is pretty compliant.

 

You may have got lucky with this. Not always the case. However, prep is a big factor as well. The more you push on the edges the greater the gap becomes between the glass and the molding, aesthetically speaking. THIS is the reason why blocks are used to keep the glass closest to the molding when using urethanes, much more aesthetically pleasing for those who are concerned but can be messy for those who are amateurs.

 

I used the "dam" process as shown in the video I attached. The dam thickness kept the windshield at the correct height while containing the squeeze out. Being an amateur, I didn't escape scott free but I am very pleased with the overall outcome. I have to say I believe installing using the butyl would be a much easier and cheaper process though.

 

use a 3m 3/8 butyl ribbon.these are just thick enough to fill the gap and still give you some room to press it down to get a good fit.also as said prep is key.get some windshield primer to coat where the ribbon will set comes in a small bottle and can be brushed on.

 

Thanks for the input everyone , this is very helpful .