Restoration - dash leak

jon_old · November 23, 2008 at 11:40 PM

I've got a leak under my dash behind the instrument cluster and on the other side behind the glove box. I've never had this area apart before, but it looks like the dash panel has support brackets that hook over the edge of the lower cowel panel and it leaks at each bracket attachment. See pic of example behind cluster: http://s461.photobucket.com/albums/qq338/j0ns_photobucket/?action=view¤t=100_0930_rev1.jpg According to the previous owner, the lower cowel panel was replaced years ago. Less than 5k miles on the car since, and always garaged, so if the panel was replaced it should still be good. I can spray lots of water into cowel vent and no leak. Only leaks when water sprayed over bracket attach points - inboard of wiper rotors. Will I need to remove the upper vent cowel panel to repair this?

C6ZZKGT · November 24, 2008 at 7:21 AM Official Post

I have a complete dash assembly out of a 65 that was removed by drilling out the spot welds. The bracket that appears to you to to be leaking is sandwiched between the cowl panel and the dash panel pieces and is spot welded together. The windshield weatherstrip fits over all of this and seals it off. If your weatherstrip is not leaking there, and many times they are, you must have a hole in the cowl below the weatherstrip. That area where the bracket is located is thicker that the rest of the seam due to the extra piece sandwiched between the two layers and is more prone to leakage.

-Fred-

jon_old · November 26, 2008 at 8:22 PM

Thanks Fred. I will replace the windshield seal. Car still has original glass so it's reasonably possible the seal is original - and a leaker.

C6ZZKGT · November 27, 2008 at 2:39 AM Official Post

Check with a local glass shop for the proper sealer. I use what they call windshield bedding compound. Do not use silicone. The windshields are tough to seal at best.

-Fred-

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