Hi, I have a 1969 coupe. A glass shop has been trying to fix a leak in the rear glass. Water is coming in at both lower corners. He has had the glass out twice and it still leaks. Any thoughts? Thanks

 

they make a silicone sealer that you can use like caulking as a meantime fix

 

I can't recall if that glass in a glue-in or in a gasket. Regardless they/you should be using urethane sealer and not silicon. Obviously there is someplace that is not getting sealed.

One method to find the area(s) that are leaking is as simple as holding a garden hose at various points along the edge of the glass. Start at the bottom then work your way up the sides, then across the top. Have one person outside holding the hose and another inside with a flashlight looking for that first drip.

Another method which I have found to be more accurate is to use compressed air and some soapy water. Fill a spray bottle with water and add some dish soap. Start on oneedge of the glass, spraying a generous amount of soaping water. Then take the air hose and spray the airtowards the edge of the glass slowly moving the air up and down that area.Move slow and be thorough.Sometimes theleak is very small andrequires just the rightangle ofcompressed air to reveal it.Don't forget to keep spraying the area being tested with the soapy water, as the air will not only push the water out of the way, butwill also dry it out.If there is a breech the compressed air will cause the soapy water to create bubbles on the inside of the glass.

If it is in a gasket, you can seal the leaky area with urethane. Lift up on the outside of the gasket with your finger tip. Often you can tell where the glass didn't seal. Stick the tip of the tube of urethane under the gasket and fill it up untill it is ouzing out. A razor blade is helpful for cleaning up the excess on the glass side of the gasket. Solvent will help clean up the rest and more often then not won't hurt the paint.

[ Urethane is very dense and will probably require a good strong caulking gun.]
[ Best to work with glass in a warm invironment. Gaskets will be more flexible]

The leak may also be on the body/ pinchweld side of the gaket ( check the glassto gasket side and the gasket to body/pinchweld side). Can use the same method to check for leaks.

If its a glue in glass (no gasket), remove the trim, then use the mentioned methods to check for leaks. After making sure the area to re-seal is clean of dust and debris, use the urethane to seal that area (this is called back-filling).Use your finger or a popsickle stick to push the urethane into thearea. The moldings will cover theback-filling when put back on. Try to keep the urethane away from the molding clips as it can make it difficult to get the molding on and off again.

Once in a great while a body seam will be the cause of the leak, although this is rare.

Hope this helps.

 

Thanks Smothers

 

when my windshield was leaking, i took off the chrome trime, squirted some silicon stuff on it and slid them back on. it doesnt leak anymore!

 

I wasn't trying to suggest silicon wouldnt fix the leak, its just not nearly as effective as urethane. Urethane will be more durable against the elements (water, cold and especially heat and sunlight. Silicon will break down much faster. You can use bathroom caulk if your looking for a quick fix.