Water leak help - behind dash
Thread Starter
Holley HP EFI w/TPI
Joined: May 2009
Posts: 553
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From: Kanata ON
Water leak help - behind dash
I've got a leak up under the dash (dash is removed at the moment) and it appears to be coming from behind the metal support, up in the corner, where there appears to be some sort of white caulking.
Where is this water coming from on the outside and how easy is it to repair?
Where is this water coming from on the outside and how easy is it to repair?
Thread Starter
Holley HP EFI w/TPI
Joined: May 2009
Posts: 553
Likes: 0
From: Kanata ON
Heater core is fine (it was a much bigger leak), I replaced all those seals/butyl tape recently.
This water is coming in above the fresh air vents, in the corner, behind the support.
I have the passenger side dash off, and carpet pulled back. It's raining outside and it's coming in.
This water is coming in above the fresh air vents, in the corner, behind the support.
I have the passenger side dash off, and carpet pulled back. It's raining outside and it's coming in.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You have leakage problems from around the windshield mouldings and/or from exposed cracks in the wiper tray area. If you are lucky, the caulking in the wiper tray area has dried up/cracked and you just need to reseal that area with butyl caulking. Otherwise, the seals around the window area are not doing their job.
Platinum Supporting Vendor
Joined: Sep 2001
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Hate to be the barer of bad news, but it sounds like someone may have already been in there if you are finding white caulk. Caulk was not used on the cars to seal anything, they used a seam sealer that hardened. It is very common for a 68-82 with rusty windshield frame to leak. There is no easy way to fix this. I had to fix our 71 about 10 years ago for the same reason. I wish now I would have taken pictures of the entire procedure but it may be time for you to seek out a really good shop that can do the proper repairs. I do sell the windshield frame pieces, but depending on how bad yours is, there may be a better route. You can start by removing your outer moldings to give you a good look at the frame, they usually rust right down in the corner of the windshield.
Justin
Justin
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Platinum Supporting Vendor
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Hopefully that would be all that is the issue. At least for his sake anyways, you can remove the rivets and re-seal the entire panel or brush the seam sealer over it.
Thread Starter
Holley HP EFI w/TPI
Joined: May 2009
Posts: 553
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From: Kanata ON
Hate to be the barer of bad news, but it sounds like someone may have already been in there if you are finding white caulk.
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
Hate to be the barer of bad news, but it sounds like someone may have already been in there if you are finding white caulk. Caulk was not used on the cars to seal anything, they used a seam sealer that hardened. It is very common for a 68-82 with rusty windshield frame to leak. There is no easy way to fix this. I had to fix our 71 about 10 years ago for the same reason. I wish now I would have taken pictures of the entire procedure but it may be time for you to seek out a really good shop that can do the proper repairs. I do sell the windshield frame pieces, but depending on how bad yours is, there may be a better route. You can start by removing your outer moldings to give you a good look at the frame, they usually rust right down in the corner of the windshield.
Justin
Justin
If you search for 'birdcage rust' you'll find many photos of areas where they tend to rust. Some pretty severe cases out there, many aren't quite as bad.
I'd look for the easy fix first, an open seam which can be fixed easily. If that doesn't do it, my next move would be to remove the windshield moldings and inspect carefully. Rust usually starts on the header or top corners. Other problem area is the lower corners of the windshield. Sometimes a hole develops just under the surround panel, below the bottom corner of the windshield.
There's a web site, http://www.corvette-restoration.com/ where the fellow has posted many photos of his project. There are a few sections showing windshield frame rust, typical of cars driven in the rust belt.
Best of luck with yours. Hope it's an easy fix. If not there are many helpful people here who may give advice on how to fix it.
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Butyl rubber is butyl rubber. 'Caulking' is a description of the means of application. You can get butyl sealant in caulk gun cannisters for ease of application. Butyl does not fully harden and will resist UV rays pretty well. It will be good for many years to come.
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Justin
Race Director
Joined: Mar 2006
Posts: 14,112
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From: Florida
Your pics would really help.
There are really 6 different main areas that can leak, one, some or all.
The bond breaks loose above the pedal structure.
The outer windshield frame at the lower lip
The cowl metal under the fender bonding mount
The fiberglass to cowl firewall joint
The fresh air lower vent.
Windshield bond to frame.
There are really 6 different main areas that can leak, one, some or all.
The bond breaks loose above the pedal structure.
The outer windshield frame at the lower lip
The cowl metal under the fender bonding mount
The fiberglass to cowl firewall joint
The fresh air lower vent.
Windshield bond to frame.
Thread Starter
Holley HP EFI w/TPI
Joined: May 2009
Posts: 553
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From: Kanata ON
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
At the very least you have a broken bond between the firewall glass and the top of the pillar/lower windshield frame.
Worst case, the lower windshield frame in several spots is rusted thru.
Or anything in between the above.
Take off the side windshield moulding and check the frame beside the glass for holes.
In the lower windshield area where the glass stop is on the firewall, check for broken bond.
In all likely hood the windshield and at least the top fender corner will have to come off for a proper repair.
Some have tried to pour liquid sealers in the area, but doubt if that will work.
Hope you find something simple.
Post some pics.
Worst case, the lower windshield frame in several spots is rusted thru.
Or anything in between the above.
Take off the side windshield moulding and check the frame beside the glass for holes.
In the lower windshield area where the glass stop is on the firewall, check for broken bond.
In all likely hood the windshield and at least the top fender corner will have to come off for a proper repair.
Some have tried to pour liquid sealers in the area, but doubt if that will work.
Hope you find something simple.
Post some pics.
