I've seen a lot of threads showing the area below the windshield that has rusted out and had to be repaired.

Similar to the issues Kortensi has been faced with during his restoration as is depicted in his thread (about half way down the page):

http://forums.corvetteforum.com/c3-g...1-pics-16.html

Is there any way short of pulling the windshield to verify whether or not you have this issue? Can you see this area from inside the car after the dash is removed?

 

What you can see behind where he cut out can be seen when the dash is removed but your not really going to see the rust damage there until it's worse than he has on the other side.



Even with the front clip removed it looks like it's pretty much covered in fiberglass. I'll take a look at this tomorrow and get some closeups for you.

 

I am in the market for a c3 vert 68-72 and this is great interest to me,
I am...ahem, scared of not checking a car well enough and it being a rust bucket,
When a car is apart is one thing but most all sellers are not going to let us start pulling the car apart how does one check for bird cage/windshield rust on a car we are thinking to buy?

 

First, there are 4 cage to frame mounts on each side. called 1,2,3 and 4. 1 and 4 are open to the air, and don't usually rust on a non-salt/snow car. the other two 2 and 3 can be accessed by pulling the kick panels for #2, there's s single screw up at the fire wall, about 1/2 way up, and pulling or loosening the sill plate cover, the kick panel just pulls out. Then take a camera and put it into the channel above the mount and snap a picture up into the channel.

To inspect the lower side of the dash, just pull the map pocket panel, you'll need a shorty Phillips for the two screws in the door hinge area, two from the center gauge bezel, three across the top.

To inspect the rear #3 mounts, there are 3"x2" plates in the front of the rear wheel wells, 1/4" hex head self tappers- 6 of them i believe, but could be 8, allow access to the rear #3 mounts. their right there.

Drivers side lower dash is not practically inspectable on a per-purchase inspection, it would require pulling the column to pull the main speedo/Tach panel.

then inspect the windshield frame through the glass. You can also pull the windshield frame vertical interior pad, and there is the inside of the vertical frame. One screw, up top and it slides out.

Front, surface rust only, bring a pick or flat tip.



Up into the channel:



Pass Dash




Rear body mount:

 

Excellent job on this thread, photos and explination. Thanks

 

If my #2 areas look like this, should I expect the rust thru on the lower area near the base of my windshield or are the causes of the two areas not related.

 

I have restored 3, C3's and am now working on my 4th. I have pulled every windshield during the restoration. I use piano wire to cut out the old glass and urethane to reinstall it. I wire brush the winshield frame and bircage and rustproof the whole surround. The pulling of the glass addresses 2 issues. It let's you see what shape your frame surround is in and address any problems with the steel. With the glass out you can also get under the fender to rustproof the area. 2. It lets you reseal and get the windshield at the correct depth so your trim around the perimeter fits correctly. I have seen too many windshield replacements that the installer set the glass too deep and the trim fits with gaps between the glass that you can fit your little finger into.
Down side to pulling the glass....
It may break and you are out possibly an original windshield. It hasn't happened to me yet. Knock on wood.
My 2 cents.

 

I am struggling with the idea of pulling the windshield during the rebuild. Not really worried about the original date code, and it has some fogging on the lower passenger side that would be better off gone. Just not pulled the trigger yet. I removed one from an old Grand Prix a few years ago and let's just say it wasn't pleasureable or painless. Any and all tips on the removal procedure would be greatly appreciated.

 

Remove all of the chrome first. You can use the same tool that you use on the gran prix if it was an older model. Be careful because the top clips are much closer to the glass than the gran prix. Once all of the chrome is removed take a thin piano wire or guitar string and start in the corner top and work the wire through the urethane. Take a small needle nose and pull it through so half the wire is inside and half outside. I wrap the ends around a small block of wood to save your hands and to give a handle on the ends to hold the wire. Working slowly pull the wire in and out as you move around the perimeter basically "sawing" the windshield out. Your wire may break at some point from the friction and sharpness of the edge of the windshield. Push a new wire through where you started and continue around the perimeter. Pull the glass and set it on and old thick blanket. Take a very sharp chisel and cut the urethane from the frame. Use a razor blade to clean the urethane from the glass. Once your frame is clean I would suggest removing the screws from the top clips and checking for any issues with the frame. I always replace the clips and screws. The new clips will last a lifetime and the screws have wax on the to keep rust issues away. Have an auto glass company reinstall the glass if you aren't comfortable with the setting yourself. They will charge about $100. If you want to set it yourself I can give you directions on that as well. Good luck.
BTW When cutting the windshield out it is a little easier if you have an extra hand. When you get to the bottom side alot of installers put a layer of butyl tape in that area. It is a little tough to get the wire through and an extra guy can be inside pulling and you can be outside. Pull back and forth easy. You are "sawing" the windshield out. It is glass and not real forgiving.

 

One more thing, be VERY careful working around the windshield with tools. One little nick, especially around the edge, can cause a crack to develop and it gets worse from there. Just don't pry against the glass with a screwdriver or anything like that.

 

Well I have all the chrome removed and found that the windshield was "LOOSE" Not attached anywhere but at the base. I did crack it while I was checking it out, but as I said previously, due to fogging in the glass, I was already thinking about replacing it. The "T-top" "T" was a little bit of a hassle to get out as there was an extremely large amount of urethane shot underneath to help hold and seal it in place. The rails, though pretty full (urethane or whatever they used to try and hold the windshield in place) look to be solid at first "poke", but time will tell as I get the glass and adhesive out later this week. Thanks again for all the help.

 

RunningMan373,

Do many sellers allow us to take trim off to see behind kick panels and such?

 

If their asking 1,500, probably not. If their asking 15,000, i think i'd check it, or walk.

 

Loose windshields are definitely a problem.
The setting material is the only protection you have against leaks and adhesion to the body. I have seen a lot of guys try to seal the reveal trim with silicone trying to fix leaks. This only closes the area behind the trim and actually promotes rust in the windshield frame. The trim is only there to cosmetically cover the frame set area. You did well to find the loose windshield at this point. You will now have a new glass, good seal, and a good look at any issues in the frame. I have seen many a windshield that the 1st gen urethane has failed and the trim and the weight of the glass was the only thing holding them in place.
Unlike a lot of windshield sets of the period, corvettes used urethane to hold them in place. Other cars of the time used butyl tape. The old urethane sets used a first generation urethane that now has been improved ten fold and is the industry standard for windshield setting material.


13 bats question is sound but having been in the glass business for 20 years in my youth unless you have a very good glass mechanic or someone real familiar with the close proximity of the top clips to the glass I would not let anyone pull the trim to look at the condition of the pinchweld.

 

I wouldn't consider buying a car unless the seller agreed.

 

This method works great and having the windshield out makes working on, under or around the dash area much easier.

The only different I'll be doing is remounting the windsheld in butyl just in case it needs to come out again. If it's urethane mounted the chances are good it will break.

 

Having been in the Autoglass business 20 years in my youth I have to disagree. Butyl is actually much more difficult to remove and keep the windshield unbroken. Butyl tape never totally dries, so when you try to get a piano wire through it, it just seals itself back up and rebonds. Urethane cures to a solid and will seperate when the wire is pulled through. Urethane also seals the frame to glass better due to the difference in contours from 1 glass to another and your frame. Unless you put butyl tape on on a very hot day it usually doesn't compress enough (especially in the upper corners) to seal correctly around the perimeter.
My .02
Dave

 

I think we used the butyl in the past (black ribbon of adhesive). Can you get the urenthane and apply it yourself or does that require special equipment to install?

 

Everyone talks about setting the correct hieght of the windshield?
I need to install one soon,
can anyone describe in detail about setting the correct height procedure to me?
so the trim will match up properly.
thanks, 69VETT

 

You need a caulking gun. You will have to modify the end on some guns to accommodate a larger spout on most commercial urethane tubes.
Always heat up the urethane before you use it. Tubes put in a plastic bag in hot water works great. The viscosity of material will be easier to pump from the tube.
Your autoglass dealer should have the following.
2 tubes 3M,Crl or comparable urethane.
Pinchweld (black) primer. For your frame.
Glass (clear) primer. For your glass.
1 roll foam 3/16 side tape. I use this to keep the windshield at the right height from the metal frame. It also is good for a novice that might not position the glass correctly initially and will keep urethane from pushing into the passenger area.
2 Rubber setting blocks. You have 1 area to put a setting block but as a novice you may cut it too small. So get 2.
Most autoglass shops will give you a partial bottle of the 2 primers for free. 1 bottle will do about 10 installations and they usually have a partial bottle they will give you.
You will not need 2 full tubes of urethane but you will need more than 1 typically.

For the novice get latex gloves. Urethane is very difficult to get off anything, especially your hands!