Rain pouring into cab through vent cavities

[67D100Pickup]

First, do those cavities below the windshield wipers where air flows to the cabin vents have a name?

It's a 67 D100.

Mine are rusted through and rain pours into the cabin.

I assume they’re supposed to drain to the ground somehow so I need to understand how that works so I can make sure those drains are clear.

Then I need to close up the rusted out steel that’s letting rain into the cabin.

The service manual doesn’t seem to have any help.

Do any of y’all have any guidance on this?

—Jeff

[PwrWgnDrvr]

It drains into the engine compartment thru 2 small holes in the firewall near the hood hinges. From the factory there was a small rubber flapper over the holes. You would call that area the cowl.

[67D100Pickup]

Ok. Then we’d say the vent cowl area is rusted through to the cabin.

How might someone close up those rusted out areas in that tight space?

And what would you use? Body putty? Fiberglass?

—Jeff

[jeffc57]

here is how i repaired my 62, best to repair with metal, but i have used epoxy like the 2part type, must clean and treat metal with anti-rust such as POR15 https://imageevent.com/jeffc/rust

[Wildergarten]

If you are not going to replace the metal, then I'd try stripping the paint, etching with naval jelly or the equivalent, rinse it CLEAN, passivate the surface with a converter such as Fertan, then go to a slow epoxy paste with glass matting to hold it if the holes are big. Once that's all cured, I'd then apply an elastomeric coating capable of taking paint to the entire interior. Then paint.

I am not at all a fan of the factory drain system, but I haven't yet conjured what I'm going to do about it. The rubber drain inserts are easy targets for rats, who then set up house inside the cabin, including the heater.

[67D100Pickup]

here is how i repaired my 62, best to repair with metal, but i have used epoxy like the 2part type, must clean and treat metal with anti-rust such as POR15 https://imageevent.com/jeffc/rust

Wow. That is quite a repair job. I’m hoping I can seal it up and have it drain properly with less work than that appears to be.

[67D100Pickup]

If you are not going to replace the metal, then I'd try stripping the paint, etching with naval jelly or the equivalent, rinse it CLEAN, passivate the surface with a converter such as Fertan, then go to a slow epoxy paste with glass matting to hold it if the holes are big. Once that's all cured, I'd then apply an elastomeric coating capable of taking paint to the entire interior. Then paint.

I am not at all a fan of the factory drain system, but I haven't yet conjured what I'm going to do about it. The rubber drain inserts are easy targets for rats, who then set up house inside the cabin, including the heater.

Yes, maybe that’s where the mice were getting in. I’ve already refurbished the heater but I’ve wondered where they were coming and going.

The holes I’m dealing with are like dime size. I’ll try the fiberglass approach and see how that goes.

[jeffc57]

You can access the inside from the cowl by removing the cowl cover and wiper linkages, you can reach your arm down to coat the inside with whatever you choose to use, though I can not recommend fiber glass unless you rust treat inside first

[Wildergarten]

The holes I’m dealing with are like dime size. I’ll try the fiberglass approach and see how that goes.

Ditto to what jeffc57 said. Remove any putty or sealant and get that metal CLEAN, both sides.

[PwrWgnDrvr]

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