The Stovebolt Site Forums The Shop Area Paint and Body Shop Windshield Sealant

I have water dripping off the dash right above the pedals. It is coming in on the passenger side near the bottom corner of the windshield.
I can't see any other leaks. I bought some 3M Windo-Weld #08609. Should I install the sealer at the offending spot or go around the entire windshield?

Chasing windshield leaks is a pain in the arse. The leak is never where the drip is. Using a sealer is a hit and miss cure at best. Try your best and save up your $ for a complete windshield reset. Good luck.🛠

Using the pointed applicator tip, cut the smallest hole in it you can. On a sunny day after the truck has set out in the sun for a while, fit the nozzle in between the body and rubber and apply a small bead all the way around.
Then,, do the same in between the glass and rubber,, all the way around.
A nylon "windshield stick" comes in real handy for this job. DONT use anything metal against the glass.
Good Luck,

The above is all good advice. The WindoWeld you referenced is urethane. You may want to get a tube of 08509 Bedding and Glazing instead. This will flow better and be easier to clean up. As Martin said, An R&R would be best, the sealer can then be placed on the gasket before install, The glass side should be sealed after the install. If its done before, you'll have a tough time keeping it from sliding off the glass, as well as a big mess to clean up. Stoddard Solvent, mineral spirits or kerosene will clean either sealant up. Urethane is the PC sealant to use, but if the glass ever needs to come back out, you'll probably need a new gasket. Hope this helps. John

I'm ordering up my front and rear windows next week- if I understand correctly, are you guys recommending that new window installs be done with a sealer? I'd sure like to get it right the first time around...

Thanks.

Sealer, YES and don't be stingy with it.

okay, thanks.

I bought the 3M 8509 window bedding that John suggested above and I am ready to install my front and rear windows in my '50 3600.

I read the Tech Tips, the Chevy Manual and a few threads here on the subject.. is the consensus now that it is better NOT to put a bead of sealant just ahead of the pinch weld area of the windshield rubber prior to installing, and instead, seal the rubber after installation?

As far as "mastic" goes, I thought that mastic was the mastic tape, as used in setting the door windows in their frames... when I do the rear window and have to join the ends of the rubber, will a dab of the 3M 8509 Bedding suffice?

Thanks for any guidance on this.

When I started doing auto glass in the last century I was taught to run a bead of sealant on the gasket in the area between the pinchweld groove and the outer edge of the gasket (do this after putting the rope in the groove). I usually ran a bead about 3/8" dia. This will squash out between the rubber and body, sealing that area. Seal the glass after its in the truck by inserting a plastic or wooden stick between the glass and gasket to make room for a small tip on a caulking tube. The factory manual says to put the seam in the backglass gasket at the top. When you put the gasket on the body you'll probably need to cut the gasket, if you do, cut it 3/16 to a 1/4 long and spring it in. The lock strip starts at the center of the bottom. The backglass normally doesn't need any sealant, but I'd use RTV silicone on the seam if you want to seal it. The 3M sealant won't harden up for a long time, hence you'll smear it every time you touch that area! John

OK, I got it. Thanks John.