04-11-13, 07:05 PM (This post was last modified: 04-12-13, 01:59 PM by 4264door.)
With a fender off the car, you can see the cowl drain that is part of the cowling. When I took my fenders off I found both drains were plugged with crud, dried leaves, needles from trees and etc. No wonder cowls rust and leak onto the interior floor and firewall. Couple that problem with leaky pivot seals and you get the double whammy effect. You can try shooting a strong stream of water into the cowl area and watch for the water leaking under the car. With the wiper motor taken off I have also seen one fellow take a compressed air rubber line and fish it into the cowling from that opening and he shot air until he saw that same crud fly out under the car. Here is a picture of the drain hole and area from a '66 1371parts car out at my friends barn.
It is well hidden for sure. On a side note, some of our fellow Mopar racers in my area block the cowl grates or weld over with new sheet metal to eliminate the air being trapped in the cowl area. Their thinking is they are eliminating a dead air space that has a detrimental effect on aerodynamics. Kind of like an air pocket. It probably does work...on a race car. Conversely, I have also seen car builders use that turbulent air space as a source of fresh air to the carb via venting to a carburetor air box (early Nascar pictures will bare this out), much like the GM version of cowl induction. 1/2 a dozen of one, 6 of another so to speak. When the car is apart I think it is a great idea to shoot anti-rust paint in these vulnerable areas, even undercoating on the outer surfaces of the inner fender areas. Something as mundane sounding as a cowl area can sure be like opening a can or worms, something seems to crawl out of the can when you least expect it.
