At some point and time the windshield was replaced in my sons 70. When it was replaced they used urethane instead of butyl. The body shop won't remove it nor will the local glass shop. They have both told me there is a very high likely hood that it'll break and they don't want that responsibility. Does anyone KNOW of a way to remove this windshield without breaking it? They both told me that urethane produced a much better and stronger seal but created a removal problem. When this windshield or a new one is put back in would it still be better to use urethane because of the stronger seal? Your opinions and help would be appreciated. TIA Pete and Nicholas

UPDATE: It's out and in one piece graemlins/hurray.gif . Thanks everyone graemlins/beers.gif

I prefer to remove the windshields with 4 feet of high tensle wire. A guitar string will work. Remove the molding and use a small pocket screwdriver to make a hole in the urethane. I usually make the hole it the top of the windshield.

Slide the wire through the hole so the wire is equally on the inside and outside of the glass. Wrap the extreme ends of the wire around a handle of some sort (protects the hands). Have someone on the inside and together pull the wiring toward the outsides of the glass and around the parameter. The person on the inside needs to take care of the trim and dash pad. The wire will cut in to them if not guided properly. The person on the outside needs to protect the paint.

Using this method only takes a couple of minutes.

IMO the 3M ribbon works very well for putting it back in. Easier to keep "neat" than urethane. I hate seeing gobs protruding outside the trim. I'm sure others like the urethane.

I've been an auto glass installer for 15 years. Never tried the piano wire but have heard it works great. Do yourself a favor and just pay the glass shop to install the glass for you, just make sure it's a reputable one. I will never use butyl again, hate the stuff. Urethane is by far superior, but much more difficult to work with. I would only charge you maybe $40 to install the w/s. Shop around and save yourself the headache. By the way, if you break the w/s, they're not that expensive to replace.

A new windshield for a Chevelle is around $100. I used piano wire with pretty good luck. I actually need to replace the windshield in my 86 Cutlass since I broke it last weekend. I was going to use urethane to install it, but then I started leaning towards the urethane. It seems it takes less effort to seat it properly with the urethane. The last time I had someone install a windshield was in my 69 Malibu and I made them do it again because it was an absouletly horrible job. Yes they broke the windshield taking it back out, and yes I forced them to pay for a new one and reimburse the labor.

Use piano wire. $12 for a roll and it'll be enough for many windshields. remove your reveal mouldings. Cut a 7 or 8 foot long pice of wire. Get inside the car and push one end of the wire through the urethane directly above the mirror, the end of the wire should be visable from the outside of the car. If it isn't visable you may need to cut into the urethane at the glass edge with a knife or razor blade to find it. Using a pair of needlenose pliers grab the end of the wire and pull about two feet out. Then get back in the car and push the other end of the wire through the urthane on the bottom of the glass in the center area of the dash. From the outside of the car the end of this wire should be now visable and pull the wire out untill all slack is removed from the inside of the car. Now wrap the wire around something like a screwdriver handle to use as a handle on each end. With one handle in each hand saw your way through the urethane from the center of the glass towards the outer edge then repeat for the other side. Watch to make sure the wire doesn't get caught on any clips, etc.
A good friend of mine worked in a salvage yard for many years and taught me this way. Before I would find a helper to be inside the car and attempt to cut around the glass one edge at a time with about a 50% success rate. Cutting the top and bottom at the same time is the only way to go, I haven't broken a piece of glass in more than 15 years!
When I install the glass with urethane I use a universal foam weatherstrip around the inside border that acts as a dam for the urethane and gives the inside a clean look, it's available at most auto parts stores in a roll and is self adhesive.
Urethane is much stronger than the butyl tape and can be set to any depth.

i like the butyl on old cars with out air bags ,its easy to work with and never had a leaknand if i need to take the glass out for some reason its not hard to get it out,urethane is stronger but i never had a winshield come out at any speed,i think urethane is for air bag cars

I'm in agreement talldeck on the urethane. I started in the auto glass business in the mid 80's, which was early enough to still see the transition to the use of urethane in the mid-70's cars (mainly GM).

From what I've learned, the use of urethane originally tied into roof strength in a rollover. Its gotten more important since air bags have been in use as the windshield is the backstop for the air bag. There's been many lawsuits over improperly installed windshields not staying with the vehicle, although I don't know that anyone's been sued over a collector car.
However, from the factory the 60's era GM's weren't set on butyl, but on polysulfide, which was a lot tougher. So why not go stronger than the polysulfide with urethane?

Everything I do will be installed with urethane. Also, I can't see trying to save an old windshield. They get sandblasted, scratched, etc. and they're too cheap to worry about it.

Jim

Jim the windshield wasn't that old. It'd been replaced at some time. I priced a new windshield and installed it was 300.00. A little incentive for me to save the old one that is in good shape. Pete

Pete,

I can understand your situation. My post was intended to do nothing more than throw out the experiences and education (glue manufacture's training) that I've had. After seeing the pictures and reading about the lawsuits, I tend to err toward the side of caution with things like this. I'd just much rather have a windshield set on urethane than have one on butyl due to the chance that it could keep someone in the car in an accident. They can, and will, come out in the right circumstances if they're set on butyl.

You won't find anyone who will promise they can find remove that windshield without breaking it. That said, it can be done - I've pulled many urethane set windshields with piano wire, a Fein knife and/ or an Equalizer. Find a local independent shop that is run by car guys and your chances are pretty good.

Jim

Pete,

I can understand your situation. My post was intended to do nothing more than throw out the experiences and education (glue manufacture's training) that I've had. After seeing the pictures and reading about the lawsuits, I tend to err toward the side of caution with things like this. I'd just much rather have a windshield set on urethane than have one on butyl due to the chance that it could keep someone in the car in an accident. They can, and will, come out in the right circumstances if they're set on butyl.

You won't find anyone who will promise they can find remove that windshield without breaking it. That said, it can be done - I've pulled many urethane set windshields with piano wire, a Fein knife and/ or an Equalizer. Find a local independent shop that is run by car guys and your chances are pretty good.

Jim

Man, I didn't realize how lucky I was to find someone in my area that runs a glass shop and agreed to install my 67 front and back glass for a few bucks. Said he remembers when he did it to 67's in the 60's and 70's. He too said he wouldn't take old glass out and guarantee not to break it. He also told me that in VA, butyl was not legal to use on windshields. Maybe he meant "shouldn't be used, or not a wise choice". But he will only use poly.