C3 corvette floors get wet
Thread Starter
Cruising
Joined: Jul 2017
Posts: 10
Likes: 0
C3 corvette floors get wet
I have a early 1976 C3 Corvette that I have nearly replaced or rebuilt the entire car {basically a frame on restoration}. All weather stripping has been replaced and is new.
Here is my problem, when it rains the drivers and passenger side floors collect water. I have adjusted the T-tops and windows to the service manual specifications. I actually replaced both floor boards because they had some rust.
The car only sits out when I bring it home {other toys in my garage} and is normally parked in my warehouse when I am not using it.
Here is my problem, when it rains the drivers and passenger side floors collect water. I have adjusted the T-tops and windows to the service manual specifications. I actually replaced both floor boards because they had some rust.
The car only sits out when I bring it home {other toys in my garage} and is normally parked in my warehouse when I am not using it.
Le Mans Master
Joined: Nov 2004
Posts: 5,254
Likes: 768
From: Waterford WI
My best guess is that you have windshield surround (birdcage) rust issues. If you check behind the kickpanels, you will probably find rust from water that made its way down from above. Remove the a-pillar moldings and the interior trim across the top of the windshield. That will likely tell you far more. Hate to be the bearer of bad news---that's probably why you needed new floors.
Thread Starter
Cruising
Joined: Jul 2017
Posts: 10
Likes: 0
I replaced more metal on my '76 then I replaced on my old trucks. I was actually thing of pulling the windshield and resealing it. I had to replace the header bar, radiator support and the floors. The only rust that I had besides the floors on the bird cage was near the front drivers section where the upright of the bird cage meets the rocker, other then that the bird cage is solid. I will check out the windshield frame to make sure. Even my frame is nice. It's a original North East car, which was a daily driver for part of its life. Thank you for the information.
Safety Car
Joined: Mar 2003
Posts: 3,585
Likes: 504
From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
C4 of Year Finalist (stock) 2019
Have you tried having someone (a helper) spray water on the car while you check around all of your new seals? This will help either eliminate some possibilities or it might direct you right to the breach. The Assembly Manual (if you have one) has guidelines for conducting the water spray test. It might also be helpful to remove the windshield pillar covers for the test to help you see along the inside of the windshield frame.
You don't need the assembly manual though...just a helper with a hose that is willing to spray for you. Don't spray in a stream, try to simulate a heavy rain while driving as your helper sprays the front of the windshield head-on.
You don't need the assembly manual though...just a helper with a hose that is willing to spray for you. Don't spray in a stream, try to simulate a heavy rain while driving as your helper sprays the front of the windshield head-on.
Last edited by Red86Z51; Aug 7, 2017 at 02:38 PM.
Burning Brakes
Joined: Feb 2014
Posts: 1,045
Likes: 226
From: Cape Neddick Maine
2020 C3 of the Year Finalist - Modified
My 76 had the same issue of the floors getting wet.(no floor rot though) Check the windshield seal, they usually leak up by the mirror. My windshield sat low in the frame had an original butyl seal.
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
Mine was due to windshield seal failure on the passenger "A" pillar. This dampened the passenger side floor It was a poorly installed replacement windshield and I was able to remove the glass intact without tools!
I also had leaks from the T-top seals but those came through at the top both through and on the windshield header trim.
The leaks were discovered when I'd driven the car to a card game and there was an unexpected and extremely heavy rain. Fortunately the car seems to have been a garage queen before my ownership and definitely after so rusting was minor and easy to address.
Should windshield removal, rust removal, treating, painting, etc. be necessary pay great heed to warnings about the corner trim that holds the T-top pins. Remove them AFTER removing the windshield and reinstall them BEFORE the windshield or you WILL nick the edge of the windshield on at least one of the four screws in the front of those pieces. Such nick WILL make a running crack!!!
I also had leaks from the T-top seals but those came through at the top both through and on the windshield header trim.
The leaks were discovered when I'd driven the car to a card game and there was an unexpected and extremely heavy rain. Fortunately the car seems to have been a garage queen before my ownership and definitely after so rusting was minor and easy to address.
Should windshield removal, rust removal, treating, painting, etc. be necessary pay great heed to warnings about the corner trim that holds the T-top pins. Remove them AFTER removing the windshield and reinstall them BEFORE the windshield or you WILL nick the edge of the windshield on at least one of the four screws in the front of those pieces. Such nick WILL make a running crack!!!
Last edited by SwampeastMike; Aug 7, 2017 at 03:32 PM.
Team Owner
Joined: Mar 2002
Posts: 44,693
Likes: 1,834
From: Huntsville AL
My first Corvette was a 1975 I bought in 88 every time it rained I had to run by the quarter wash and vacuum out 2 inches of water from the pass floor. Back than I never did figure out how the water was getting in but now 30 years later I know. Rusted birdcage for that car as I do recall trying to remove a screw in the upper header and heard/felt crunchy rust so I just stopped right there.
I can honestly say this first Corvette was a POS rust bucket but I learned a lot about Corvette's owning that car for a couple years.
I can honestly say this first Corvette was a POS rust bucket but I learned a lot about Corvette's owning that car for a couple years.
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Michael S. Palmer
Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
When I bought my '71 in '95, it was an old show car, so only had like 130k on it, Mid Atlantic region.....convertible with hard top....car was really nice looking and the frame solid...BUT, it leaked something fierce....I traced it down to the silly stainless over the top of the windshield and down the sides, it had lots of open space to suck up water
the cure for that was to pull the stainless ALL off including the interior trim.... clean up the steel which was previously painted with w/s outta position, lucky ME.....and so with it all naked, down to the frame and glass still installed, I took many tubes of RTV black to completely fill the open spaces/channels/gaps and then put the stainless over top pieces back, then wrapped with black vinyl glued down good, then put the glass trim back, totally bedded in the RTV did not bother with the retaining clips..
the top gasket seals well to the vinyl...no leaks, the tops of the fenders and the trim is totally filled and sealed to the glass/metal/body...no gaps......
over the years, it leaks a bit around the side windows....but that's the lousy new rubber seals, nothing so bad as to get all ape over.....
the cure for that was to pull the stainless ALL off including the interior trim.... clean up the steel which was previously painted with w/s outta position, lucky ME.....and so with it all naked, down to the frame and glass still installed, I took many tubes of RTV black to completely fill the open spaces/channels/gaps and then put the stainless over top pieces back, then wrapped with black vinyl glued down good, then put the glass trim back, totally bedded in the RTV did not bother with the retaining clips..
the top gasket seals well to the vinyl...no leaks, the tops of the fenders and the trim is totally filled and sealed to the glass/metal/body...no gaps......over the years, it leaks a bit around the side windows....but that's the lousy new rubber seals, nothing so bad as to get all ape over.....
Thread Starter
Cruising
Joined: Jul 2017
Posts: 10
Likes: 0
I appreciate all the information from every one. The windshield seems to make the most sense, as it was replaced at one point or another. probably when a previous owner nosed the right side. I will inspect the windshield frame also for rust. As one reply mentioned his '75 as being a POS, I have to agree that my '76 falls into the same category {It is almost like owning a boat, Bust Out Another Thousand}. As for the black RTV, it works till you have to take it apart. Thank you