Leaking 63-67 Coupe

[Roy S.]

This is hypothetical at this point because I do not currently have a 63-67 Coupe. however I have had several. Some leak when in the rain some do not. Those that leaked always were restored or had the windshield replaced. What causes the leak? How do you fix it? thought on the correct way to fix this problem would be appreciated.

Roy Sinor

[kenrobb]

Re: Leaking 63-67 Coupe

Roy, when I first got my 65 coupe in 65, it leaked like a sieve on passenger side. Keep getting Vicki's feet wet when we went around a corner int he rain. Come to find out the windshield was not caulked on top in middle third. No caulk at all. Must have been short armed guys on the line that day. Adding caulk was the solution ( I thought).. It still leaked! The design of the doors at the front edge just under the outer edge of the windshield is such that the door line and the body line don't match perfectly. we ended up putting roofing felt under the rubber gasket on the door to shim it up to seal against the body. No that might fix the next car, but think each one is a bit different. In judging cars over the years, I have seen different stuff in this area, so someone was trying to fix a leak. The coupe doors do spread over time along the top which creats a loose gap along the front upper edge of the door. Sometimes you can see daylight from inside the car looking up and out from foot well area. Long winded I am, so will quit.

[Robert C.]

Re: Leaking 63-67 Coupe

Hi Roy, Good to see you on the page! When I got my 65 coupe ,we drove to Bowling green in the rain. We had 3inchs of water in the floor on both sides. I found the place,it was pouring in. The main spot is; If you open the coupe door , you will see a rain gutter going around the door opening on the body side. Follow the channel forward to the 6inch long rubber strip mounted to the inside openning. At the inside of that rubber there was a crack and a hole back in the corner. I filled that with sealent and also the triangular weatherstrip on the door front/inside area, where the drainhole is. I am dry as hell now! We drove in a downpour two weeks ago at 80mph. My windshield has been replaced but doesn't seem to leak at all around it. I used clear silicon sealant. Later, Bob


Texas Chapter NCRS

[Jack H.]

Too simple?

Above comments regarding seal around doors are applauded -- we all know there was an 'opps' issue with respect to door/roof dimensions during initial design cycle that plauged the assy line through the 'mid years. Then compound that with differences in AO Smith vs. St. Louis body parts....

But, here's one that might be too simple that I've seen repeatedly on 'restored' cars. Windshield glass went into rubber gasket. Glass and gasket were 'sucked' into windshield frame using wire rope/string method. Then, sealant was applied around the front side windshield frame/gasket interface.

Factory method was based on caulk 'rope' that was 'stuffed' into place to fill. Almost from the 'git go' the shop manuals showed the use of gun applied caulk for windshield replacement. Hence, a minor difference between factory original front windshield install and service/replacement technique.

I've seen two things here that feed on each other:

(1) Glass is 'popped' into rubber gasket WITHOUT the use of sealant between

glass and the inside of the gasket.

(2) Use of gun applied caulk around the outside of the gasket vs. hand stuffed

caulk rope.

Issue one makes the installation rely solely on the native integrity of the compression fit of the rubber gasket squeezed by the inner glass and the outer windshield frame. If/when water manages to creep between the glass and the gasket, wind forces it to seek ANY path around the glass and into the car's interior....

Issue two fails to FORCE the gasket to lay flush against the outer surface of the glass (puckers, ripples, Etc.) and causes an interaction between fault #1 and fault #2. Lacking access to orignal caulk rope and the patience of Job to poke/prod/fill the outer frame area beneath the reveal molding, the best solution(s) is to REALLY seal the gasket to the glass well (super glue around the outside works like a hose presuming you don't want to attempt to re-use the gasket on your next windshield replacement) before you rope 'er into the frame and then apply caulk via gun LIBERALLY around the exterior....

[j. Wright]

Re: Leaking 63-67 Coupe

Roy- The answer to your question can probably be found in book available from Cincinnati, "Corvette Water Leak and Wind Noise Solutions" by Michael Davis. I have tackled this problem head on and found it best to leave the car in the garage on rainey days. J.Wright

[Loren L.]

Re: Leaking 63-67 Coupe

In many cases on restored cars, it is not the windshield at all but the wiper area - in the process of "restoring" we find this big glop of caulking/sealant piled up in the wiper grille area. It looks terrible with the grille out! (We seem to forget that wouldn't couldn't see it before.) I did this on my '63 and wondered where the water was coming from the first time I washed the car. When I finally contacted the original owner and asked him to relate stories about the car, one of his favorites was that it had been to 7 different Chevrolet dealerships across the country over a period of two years before the leak was stopped.

[Don]

Re: Leaking 63-67 Coupe

Roy,Way back when I drove a 64 coupe as a daily driver I had a similar problem.The car was only 7 years old yet it leaked on the passenger side everytime it rained.Assuming that there is no damaged areas under the wiper grills,try cleaning out the drain hole under you rocker panels.I have found these stopped up with leaves and misc.crud on several cars.When rain enters the wiper grills and can not exit the drain hole,water backs up and enters through the interior floor vent.Just another suggestion that worked fo me. Don #31753

[Don Hooper (50543)]

Re: Leaking 63-67 Coupe

Roy, I am not an expert, but have my third "mid-year" coupe and they all leak like a sive. I have heard stories of mid-years that don't leak but have put them with the "first metal split-window" stories. Don H.