Vette Gator

I'm in the middle of sealing all the leaks in the front of my 76. While the assembly manual is some help, I'm trying to understand the General's logic. As far as I can tell, water running down from the windshield will go over the lower windshield support along its entire length:



The water will then fall into the "trough" located in front and below the lower windshield support. This trough is open at both ends. Is the water supposed to be channeled down the front face of the birdcage pillar or down the side of this pillar on the face where the door hinges mount? I'm trying to work out exactly what needs to be sealed to keep water out of my interior. The P.O.'s solution was to fill the openings at both ends of the trough with expanding polyurethane foam.

Any information on this would be greatly appreciated.

Apologies to 69Vett for borrowing his picture. With the front fenders off of his car, it's really easy to see the sections I'm talking about.

RunningMan373

You know. something very interesting along these lines, and what i think is the cause of all the bird cage rust. All together, along the top of the W/S frame there is the Sheet metal top piece. along this piece, there is a stamped in trough, about 1/8" wide. At the bottom of this trough, there are little oblong holes, spaced about 4" apart. Thing is, when the T-Tops are installed, these holes are in front of the weather stripping,, allowing what ever water is present to travel up the W/S and drop directly into these holes, and through them, onto the top W/S support. There's your water inlet. Design mistake, not caught early, not caught by '73 at least. Rust takes time . I sealed these with RTV, the whole channel, and W/S top is now dry as a bone. Still have to have the top bar replaced one day.

Vette Gator

This is definitely something I'll look at since I have this whole area apart for R&R right not. The water I'm thinking of here isn't water that's leaking in, but about the water that hits the outside of the windshield when the car is being washed or in the rain. What path was it supposed to follow?

Easy Mike

Water will run over each open end of the wiper bay and down to the inside front corners of the fenders.

Seal the entire wiper bay with 3M automotive undercoating in the rattle can. That will prevent water from seeping in along the cowl.

Vette Gator

So the water is designed run over the hinge bolts?

DZRick

I think it's designed to drain out through the holes at the bottom in these pictures.

69Vett

No Apologies required, I post pictures to help everyone !
No, the main water path runs down the sides of the fiberglass firewall,
and eventually drains out a small square hole about 1" square,
between the inner firewall and the outer fender.
some small amout of water that may fall on the outside corner of the firewall,
will drain down onto the door hinge area. 69 VETT

Por 15 works very wel to seal the wiper area !

Vette Gator

Thanks for the information. Having these pictures of disassembled cars is invaluable in seeing how they are put together. I'm beginning to understand things a lot better. In the picture below, there is an "ear" of fiberglass that sits on top of the lower windshield support (circled in yellow). Is there supposed to be a gap between the birdcage metal and the underside surface of this "ear" or should this be sealed? This fiberglass part is about 1/2" above my windshield frame and if it was sealed by the factory in 1976, all that remains are tiny pieces and dust. I also have the lengthwise gap between the fiberglass firewall and the windshield support that's in this picture, and I know that this also needs to be sealed.

DZRick

Where you circled in yellow and if you follow that down to the bottom is where the fender bonds to the cowl. It's the bonding strip.

After re-reading your post, I'll say that I don't think there should be a gap.

69Vett

you want 0 gap there, if that area is not sealed it will allow water to enter under the bird cage, and into the cabin area, that is a very common area to rust and seperate. 69VETT
another picture to help you see...

Vette Gator

That's what I thought. I'll POR-15 this, then completely seal to the "ear" of the fiberglass firewall. I am bound and determined that water will not enter the cabin again. I've had to replace the top bar of the windshield frame, the case around the speedometer and both floorpans because someone left this car sitting out in the weather for who knows how long.

Easy Mike

No. Water runs along the sides of the cowl to the weep holes as posted and visible in the pics. With the fenders on the car, water should never run over the hinge bolts.

If the weep holes are clogged up (it happens), water will collect at the bottom of the fender until it's high enough to enter the kick panel vents.