1966 interior leak

[Richard Weddle]

hello corvette experts
my 1966 327/350 converible leaks when it rains
the leak is behind the dash and rain water falls directly onto my left foot
any ideas on diagnosis and treatment?
thanks

[Bill W.]

Re: 1966 interior leak

Richard,

For what it is worth, my '66 coupe was leaking in the same place when I drove away from the dealership. I fixed mine by moving to New Mexico (no rain). I suspect the windshield gasket, but will find out for sure in a year or so when I repaint. Let's see what others have to say. Good luck, Bill

[John H.]

Re: 1966 interior leak

Could be the seal where the base of the driver's side wiper transmission attaches to the plenum panel under the wiper grille. Remove the wiper arm and the vent grille and look for cracks in the bead of sealer around the edge of the base of the wiper transmission. Get under there with a light and observe the area around the wiper linkage arm while a helper directs water through the vent grille first to see if you can find the leak path.

[Wayne K.]

Re: 1966 interior leak

Richard,

I think John has sent you to the right area to investigate. One other tip that has worked to find serious leaks is at night in a completely dark garage have a helper hold a bright light under the dash and observe from the outside for any sign of light showing through. Also you might check with a shop that installs auto glass as there are leak detecting devices used in that industry.

Wayne

[Gary S.]

Re: 1966 interior leak

Notwithstanding the advice you received from the other posters, I will relate my experiences with my 66 convert that leaked. I had replaced all of the weatherstripping with new and still had a terrible leak. I finally located it by having my son dribble water on the windshield using a very controlled source. As soon as the water hit the area of the windshield gasket at each corner, where it goes from horizontal to vertical, I had water leaking down into each footwell. My solution was to gently pry up the rubber gasket that seals the windshield to the pinchweld and lay down a heavy bead of black silicone on both the upper and lower portions of the gasket. I then pressed the gasket down into place and taped it so it wouldn't rise up. Once the silicone cured I used a sharp razor knife to trim it away. The car was never judged but I believe that if you are careful you can probably conceal this. As a side note, when I pulled the non-original windshield out, prior to a complete paint and restrip, there was dum-dum or cauld or some other "stuff" that seemed to be serving the same function as my black silicone.

If this isn't you arean, then I would highly suspect the area where the windshield wiper posts pass, as John suggests.

Gary

[Robert C.]

Re: 1966 interior leak

My 65 would fill up in the rain. A good way to test this is to duct-tape all around the front windsheild between the glass and trim and go through a car wash.
On my last road tour, rained for 300 miles,with the tape, I never got a drop inside!