Greetings! Now where is this rust coming from?

[sixtwo]

Hello, all
BACK STORY:
New here, just picked up a 70 c10...long bed, auto, 307, nothing special....
Not my first classic, but my first living on the West coast.
She's not pretty. Dent in the bed and cancer/ rot on the doors, rockers, floor pans and kick panels. Actually not that terrible but I was still going to walk away from it. Has new tires, exhaust and shocks all around.
Was about to walk away when the seller said he's take $300 for it. How could I say no? The abundant yellow jackets came free with the truck too!

Anyway, ripped out the rubber mat flooring and say a lot of moisture and rust. Looks like it comes down the inner kick panels and onto the floor which rotted out my rockers and lower doors.
Question is, where is the water coming from. Seems to be a common issue. Is it from bad window sealing? Or does it run down the cowl some how?
I want to fix the cause before I start on the result of the cause.
Thanks for any help!


This is the photo from the ad where I picked it up

[dfj73]

Check the cowl under the windshield where the body panels come together

[18436572GMC]

Check the area around the drip rail on the top of the cab. a hole or bad seal there would allow water inside the cab.

[jorgensensc]

Windshield area. Look where the dash meets the windshield, in each corner you will see a factory hole. Water tends to accumulate there and the factory put a drain hole there to get the water off the dash and onto the floor. Hence your rotted kick panels.
Shawn

[slow-1]

Welcome...that is one fine $300 truck.

[PanelDeland]

WELCOME!!! That rust is factory!!


Take the cowl panel off and reach down the side of the cowl area.You'll find a lot of debris in there.You can pull some of it out,use a shop vac(use it thru the interior vents also) and then flush it out with water.After you do that screen the cowl before putting it back on the truck.You can glue screen to the bottom or get commercially made ones from a vendor.There are drain hole in the bottom of those vents,you want to make sure they are clean and clear.

[swamp rat]

Most of it is covered, reseal the drip rail, look under the cowl at all the seams and the antenna hole, the rubber around the windshield dries and shrinks and there are metal seams under the rubber. When you do clean out below the vent openings grab some shop wire and be sure you find the drain hole and make sure its not plugged when your flushing/vacuuming it out.

Next time it rains get under there with a flash light and look for where its coming from.

I thought i had mind fixed until i had to park my truck in the driveway to do a lift kit swap and the monsoons came, after a couple weeks i figured i'd better check and found mass water soaked into my carpet and under layment pad, still have the seat out and carpet and pad in the garage, the pad has still not dried out and is holding the water like a sponge..

Nice project truck too btw~!

[sixtwo]

Great ideas! I will check all that out. Much appreciated.