Rust Holes in the Cowl -- Help!

[3 Speed]

Reading the thread about moss and dirt in the cowl vent led me to clean out my cowl, and there I found my cab-leak source -- a few small rust-out pits/holes on the passenger side on the cowl underneath the grill, to the right of the wiper arm.

How the heck can you fix that?

[SmoothJ69]

I may be wrong but I thought the bottom of the cowl is the top of the interior back behind the dashboard so if you have holes in there I would think you'd have to fix it from inside. Basically think about where the wiper motor is.

[3 Speed]

So take out the heater box, blower, etc.. What then to repair the holes -- JB Weld, epoxy?

[SmoothJ69]

again this is only my opinion but I think if I was going to bother taking the interior apart to get to the holes, I'd cut out the bad parts and weld a patch in.

[Art]

I'd be tempted to pressure wash both sides (after stripping out the firewall pad) and wiper motor to see the extent of the damage. Then you can deal with it right. You should probably also ask yourself how long you want the repair to last.

A quick fix for a beater could be as simple as a caulking gun and silicone sealer...

If it is only light pinholes, I'd shoot some tar-based undercoating in there (Tri-Con [made in Ohio] is my preference). You can move it around in the cowl with a compressed air blow-gun, and then it will stay sealed. That stuff dries nice but doesn't get brittle. Keep in mind you don't want to create a water dam, it needs to drain.

If it has holes big enough to stick a pencil through, then it is time to weld in some patches or another panel.

[67mann]

You might find this helpful to know what or where your your problem exsist
http://www.fordification.com/forum/view ... spot+welds
go to the bottom of the page

[3 Speed]

Thanks, guys. It is obvious the truck was painted at the factory AFTER the cowl was assembled, as the rust is in a area that hardly even had primer.

I wish we could snap the thing apart and put it back together, but I assume the cowl is riveted shut, so any welding would have to be from the cab-inside side of the cowl.

[Ranchero50]

The simplest repair is to remove and replace the cab...

As said above a pressure washer will show just how bad it is. You can remove the windshield and start removing spot welds until the upper cowl is free and then repair the lower cowl but I'd rather repair the floors on a cab with a good cowl than repair the cowl on a cab with good floors.

Jamie