leaky cab

[baileyx7]

I have an 85' I have a leak on the passender side above the kick panel, i do not think its comin from the windshield. The water is running down the kickpanel from somewhere, a door bolt or where they seal the cab up behind the cowl or fender?? any help would be greatly appreciated. New to the board, will be completley redoing the a/c system on my truck soon, i know i will have questions then too....

[gchemist]

Welcome to the site.
First check the heater core. If it's not raining, the heater core is busted. If it leaks only when it rains, the cowl area may be rusted out.

[baileyx7]

Def, not the heater core, its clear water dripping after a rain or i wash it. I did a search and got some ideas....ill post my findings later. But feel free to post more ideas guys.

[willett]

Apologies In advance if this is jumbled and doesnt make sense, im hammering It out on my iphone

I'm restoing a '73 cab right
Now that has holes in about every place that could rust through and here is what I have found:

The windshield sill that the rubber mounts to has a drain hole on either side, it will direct water down through the vent duct and to the ground. Over time that water will eventually rust the s&$t out of the upper part of the kick panel behind the dash and run down the kick panel. Sounds crazy I know, but it's happened on both sides of my cab.

Second it could be that the seam between the inner and outer firewall has gotten plugged up with crud and rusted through. I am in the process of making a plate to cover the inner firewall area where the wiper arms reside.

The next possibility is that water and condensation behind the heater motor cover has blown a hole through rye firewall. Every time it rains water is running into the firewall, through the heater motor cover > firewall seal and coming out around the heater core hole

Third is obvious: leaky heater core


You would be amazed to see what 30+ years of a minimal amount of water will do to steel that never sees sun.

If I were you I would be inclined to remove your glove box, and vent cover butterfly thing and prod at the upper bit of the kick panel first. If it's rusty its more than likely the windshield seal
Posted via Mobile Device

[burb1085]

I've heard (on another site), that there is a replacement piece that is longer, to make the water flow away from the affected area. I think you can reach it from the vent hole behind the kick panel. Not exactly sure where to buy it. http://forum.73-87chevytrucks.com/sm...c,22630.0.html

[tucsonjwt]

My 76 had a defective pinch weld from the factory in the upper right corner. Instead of laying flat, that area of the sheet metal had a slight bump outward, causing the windshield rubber not seal properly. It looked fine from the outside, but when Safelite glass finally pulled out the windshield for the third time I saw the defect and they hammered it down and applied a little silicone and all was well. On that 76, years of leaking caused water to collect on the floor next to the kick panel and caused the floor to rust out at the seam.

[baileyx7]

OK guys i found the leak!! The seal to that vaccum operated vent thingymajig was leaking, i cleaned it all up good and put some silicone around it,,,,,,,we will see. On another note, looks to me the cab is designed to shed its water down beside the cab in between the cab and fender. The water runs down right on top of this vent thingy,AND, the blower motor,,,,what the heck keeps the blower motor from getting wet?
I also shined the light down into the fender cavity and no rust so far. I also took the cowl off and cleaned it out good, a lil pine needles in there but not too much crud. WHen i pulled the cowl off there is another vaccum canister under there, what does that control?

[burb1085]

Probably has something to do with a/c or heat.