Join Date: Jun 2009
Location: Baton Rouge, LA
Mad Max is offline
Re: Windshield seal leaking... how to fix?
In alot of cases, the reason for leaks is rust. The pinchweld (the area the windsheild fits into) rusts under the urethane and creates a leak. If you are planning to keep the truck for a long time, the way to fix the rust (almost permanently) is to pull the wshield - there are 2 specialized tools to do this, one is an L shaped blade on a handle with a pull handle attached to it, the other is a spade blade which is very expensive. Next - sand blast all rust, epoxy prime the bare metal, if there are any holes, fill them with JB Weld epoxy putty, sand the putty smooth. JB Weld is bullet proof. If you are careful, you can put the putty on smoothly. The next step is to use pinchweld primer - bonding primer for the urethane that the sheild sits on. Urethane comes in tubes for caulk guns. You have to cut a big 'V' in the applicator tube to get the right shape for the applied urethane. It looks like an upside down V. As the windsheild is set, it pushes the point of the V toward the pinchweld and spreads the urethane for a good seal. It helps to have 2 people to set the wsheild unless you have a big suction cup with a handle on it. On S10s, there is a rubber widsheild molding. This only fills the space between the wsheild and body. I glue this to the wsheild before I install the glass. You can buy it in a roll or precut. It makes the job alot cleaner if you put the strip on beofre installing the glass. BTW, wear those mechanic's vinyl gloves. The materials you use for this job will not come off. It will have to wear off of your hands.
I guess this is more than you expected, but at least you know what's involved. It's really not difficult, the biggest PIA is sandblasting the rust areas. Sandblasting is the only real way to get all of the rust out since it gets into the rust holes. Grinding only gets surface rust off. If there is any rust left, it WILL come back.
After all of this, you can do a quick fix with clear RTV silicone caulk. Seal the wsheild molding all the way around. I put a really thin bead on each side of the molding and smooth it with my finger after dipping it in water (finger). Once the silicone dries, you don't notice it. You can also lift the molding edge and put a thin bead in there.
1)'82 S10, 383, 700R4, Shorty
2) '85 S10, 3.4, 700R4 4x4 stretch cab (Redneck) 3) '90 S10 2.5, 5 speed shorty
4) '91 S10, Built 3.4, 5 speed shorty (Voodoo)
5) '92 S10, 2.5, 5 speed shorty, (Barbie)
6) '83 S10, 327, TH 350, shorty (13.00 best)
7) '92 S10, 2.5 5 speed, Shorty
8) 1979 LUV, Buick 3.8 V6, TH 350 Shorty.