I am getting ready to install the windshield and rear window in my '69 Super Bee. I have installed about 4 windshields/rear windows but I have had two of the windshields leak. I have searched online for some videos and tips but there seems to be a lot of conflicting information.

I am installing a new windshield with a new gasket. The rear window is a used piece which I will be installing with a roll of bead window sealant.

Here are some questions:

Are you using anything special to clean the glass/channel prior to installing the glass?

What type of butyl sealant are you using? I bought a tube of 3M Window Weld (expensive!) but is there something better that I should be using?

The channels are freshly painted. Is there a special type of etching primer that I am supposed to be applying to the channel or glass prior to installing the glass?

Does anyone have any pictures of where exactly they are placing the sealant on the bottom channel of the windshield opening?

When installing the windshield, are you installing the top first and then working your way to the bottom or are you installing the bottom first?



Thanks!

Stan

I don't know if my methods are the correct way, but my stuff has not leaked a drop.
1970 Charger. For the rear glass, I laid a 5/16" butyl rope on the window channel about 1/4" inboard of the edge of the metal flange, then set the glass on top of it. I had metalwork done in the channel so I knew that there would be some uneven spots that would not seal with that butyl stuff alone. After setting the rear glass in place, I squirted that gooey black sealant around the perimeter on the inside and spread it with my finger, making sure to fill all gaps. ZERO leaks and the interior trim pieces cover the sealant edges.
For the front, I put sealant on the entire perimeter of the window channel AND on the inner channel of the gasket where the glass fits into. I set the windshield gasket to the opening and hold it in place with duct tape then set the glass in, bottom first. I use a plastic spoon/paddle to work the glass into the channel working from the bottom up. It takes me awhile but after the glass fits in the channel completely, I use a new rope lock strip.
Again, there may be other methods that work other than mine. I may be overdoing it with the sealant; others might only use it in the bottom corners. I just figure the tube will harden in a few months if there is any sealant left in there, might as well use it up.

Frankenduster,

Thanks. That is good info. I think I just need to be a little more generous with the sealant. Things seem to get messy very quickly, though.

Stan

I'll agree with Frankenberry on some of his install techniques, I generally purchase 3/8" and a roll of 5/16" window tape, as some vehicles require the 3/8 tape to bring the rear window up to height, in setting the back window, I make sure the glass and channel are clean, I'll usually wipe them down with lacquer thinner, apply the required tape based on measuring the glass and channel depth just under the installed moulding height, I'll start the tape install in the lower center of the window channel so that my "joint" ends there...best to have both tape sizes on hand in case you need to reset the window higher/lower based on the moulding install, after setting the window in place, I then install the moulding immediately, also based on the rear window angle, you may need to use rubber positioning blocks at the bottom glass perimeter to keep the glass centered as it's setting


As far as the front window install using a gasket, A NEW gasket and clean channels, If I can let the gasket sit out in the sun for a few hours before install, that helps make it more pliable...I apply adhesive (approx a 1/4" diameter continuous bead in the "VEE" of the channel) along the entire lower channel and approx 12" in length from the bottom of the side A pillar channel towards the roof, with NO sealer along the upper roof channel then install the gasket, then position the windshield in the bottom lip of the gasket, then slowly work both A pillar gasket lips over the glass starting at the lower corners working your way up equally on both sides, then finish up with working both top gasket corners equally until I finish in the upper center of the gasket, this way I stress the glass and stretch and seat the gasket equally during install, sealant, gaskets and windshield install should be done spontaneously, don't allow the sealant to dry/harden before windshield install


Mike

DAYCLONA,

Thanks for the info! I will be picking up my windshield and gasket today but probably won't have a chance to install in for another week or so.

Stan

I agree with many ideas above, Always use rubber spacer blocks and butyl rope on gasketless glass. Do not use a tube sealer to install them.

Let's talk sealant, It is most important. The car will flex, the gasket will surely flex, so I believe a hard curing sealer is wrong for a gasket installation. that pictured urethane is for Late model vehicles, not for this application, ask a competent glass shop guy who spent his career in this industry. Bedding and glazing compound seems to always leak in my experience.

I used a liquid butyl which stays flexible. My oldest install I still own stayed leak free for 14 years in a daily driver parked in the weather B-body, just started leaking at drivers corner.