I need to seal my windshield....

[pbm]

I'm getting a large puddle on the front passenger side floor after a strong rain. I took it back to the guy who installed the windshield a few years ago and he 'resealed' it for $40 but it is still leaking. (he ran caulk under the molding and from the inside).
I decided to give it a shot myself so I ordered a new windshield molding and removed the old one today.
A website suggested that I use polyurethane caulk but said that silicone or even latex with silicone would work.
I plan on installing the molding before the caulk sets.
Does anybody have any experience with this kind of repair?

This is on my 2002 Buick Century.

 

[sciphi]

Look for leaks around the HVAC inlets, or check the A/C evaporator drain isn't plugged.

Is the door trim and weatherseal intact on the corners?

This sounds much more like a plugged HVAC drain overflowing into the cabin than a windshield leak.

 

[tomcat27]

windshields are installed with a urethane adhesive because they are stronger than silicone - ( 800 psi, if I recall) and this is important in the event of a crash as the windshield is a structural element. that being said, you dont need to use urethane unless you pull the windshield. (requires some skill to not crack or ruin it) the leak may actually be due to rust (from an improper installation) or may even be leaking from the cowl. Pull the trim to get a better look.

 

[pbm]

Sciphi: The fact that I use the A/C all the time and it stays dry until a heavy rain leads me to believe it's a leak.

Tomcat: Could you explain "leaking from the cowl"?

 

[AandPDan]

If the windshield is leaking, the only sure fix is to have it removed and reinstalled. As Tomcat says, it can break while doing this.

I had a leak in my truck, from improper installation. It did rust out a spot on the rim of the windshields frame. I had to have the glass removed and a body shop fix that.

I got lucky. They didn't crack the glass and the window is no longer leaking.

 

[sciphi]

The "cowl", or that black plastic piece underneath the windshield wipers, can have the sealant dry out and cause leaks.

Have you tried drenching the affected area with a garden hose to see where exactly the leaks are coming from? Or did I miss that part?

 

[oilboy123]

I used Permatex flowable silicone on an old Dodge truck that I did not want to tear out the windshield.
It worked, so I'm happy. I have also found that a little tube goes a long way.

I have also used to to fix a wet dry vacuum filter that was tearing on the rubber. I also repaired woofer dust cap on some speakers I built many years ago.

I feel that there are many applications I could use it for that I have not even thought of.

 

[pbm]

Sciphi:
I haven't checked it with a garden hose .
I guess I'll have to remove a lot of trim inside the car to watch where the water is flowing from.

Tomcat:
That's an interesting point about the windshield being a structural element during a crash.

As far as the cowl...I never liked the way it looked after my windshield was replaced (it seemed loose) but it didn't leak for the first 3 or 4 years. Dryed out sealant in the cowl is a very good possibility. I'm stopping at a friends body shop today to get his thoughts on where I need to seal.

 

[pbm]

I think I've found my problem.
The weatherstripping above the cabin air filter had dislodged causing water that runs down the windshield to go straight down into the passenger compartment floor rather than being diverted.
When Tomcat mentioned the cowl it got me thinking and I googled "water leaking into Buick Century" and it seems to be quite common with W body cars. (Thanks Tomcat...in fact thanks to all for your help).

I did have a slight leak from the top of the windshield because during a heavy rain I would occasionally see a few drips onto the dashboard. This was verified when the glass guy sprayed some type of foam on the molding and then blew compressed air from the inside to locate the leak (he then caulked it on the inside and outside). When the floor was still wet after the next rain I ASSUMED that the windshield was still leaking.
I'm keeping my fingers crossed and I'll report in after the next heavy rain.
Thanks again.

 

[oilboy123]

Looks like you are on the right track......