plague of the 67-72 chevy truck

[MR MAGOO]

over the years all the 67-72 trucks i have seen has 1 common problem. the cowel area leaking rainwater down into the vents rotting them out then going down to the rocker panels destroying them and eventually rotting out the cab corners. i know someone has come up with a better way to prevent this from plauging trucks after the damage has been repaired. i painstakinly repaired all the damaged areas 7 years ago and now it has returned. what can be done to prevent this??

[Americanrider]

Flushing out the cowl area every couple of years helps, look at the puddle of leaves and dirt on the ground. All of that mess builds up in there and retains moisture. A screened cowl will help keep the garbage out, some vendors sell them or make your own from Stainless steel screen.

I have considered opening up the bottom drain and making it bigger so that it would dry out quicker. (see red arrow) It would also give me room to spray some undercoating in there.

Anyone else have some ideas?

[HuggerCST]

I cut a door into mine(where the red sqaure is)while the fenders were off, cleaned it out, blasted it, undercoated, and screwed a sheetmetal plate over the hole. I bought a screen to keep the leaves out of the cowl also. On the rockers and corners, I undercoated them good on the backside. Hopefully they will last a while.

[whatnow123]

What about sealing off the cowl area? I remember seeing a post of someone welding it closed. I'm not even sure what purpose it serves any more with a new style AC available or if it even had anything to do with heater/AX. The only thing I can tell is it's for the side vents in the kick panel, which I'm closing off as well.

Having just repaired the rockers and kick panels, I'm of the opinion that: 1, this isn't something I would like to do again and would like to prevent it from happening in the future (or at least minimize it, but my truck won't see much weather or water once it's done) and 2, there is no such thing as an original rust free cab.

[sleepyboy]

I cut the bottoms out of mine, undercoated the cowl channel and put in the garbage screen

[shifty]

Shave your cowl

[68speedalert]

Originally Posted by whatnow123

What about sealing off the cowl area?...... if it even had anything to do with heater/AX. The only thing I can tell is it's for the side vents in the kick panel, which I'm closing off as well.

You're right about the side vents. However, with the factory a/c &/or heat systems, the cowl is where the air that the blower blows, comes in.

[MR MAGOO]

i also like the idea of closing off the vented cowel area,welding a plate in place of the grid wood be good. maybe someone will post us some picks of how theres was done

[Aarons72s]

I clean them out and seal them as well as I can, rusty metal primer and black equipment enamel and sometimes spray in bed liner. But the main key is keeping the leaves and twigs out. The cowl trash guards are a must! If they put them in at the factory I have a filling that 90% of the cowl rust problems would be solved. The only thing that you cant prevent is salt. Just my opinion

[davidh]

Originally Posted by Aarons72s

I clean them out and seal them as well as I can, rusty metal primer and black equipment enamel and sometimes spray in bed liner. But the main key is keeping the leaves and twigs out. The cowl trash guards are a must! If they put them in at the factory I have a filling that 90% of the cowl rust problems would be solved. The only thing that you cant prevent is salt. Just my opinion

ON SOME OF MY OLDER TRUCKS THE COWL VENT SCREENS ARE THERE AND SOME ARENT. DID SOME COME FROM THE FACTORY THAT WAY?? I SAW MY 68 HAD SOME ACCUMULATION OF LEAVES IN THE KICK PANEL VENTS AND BEFORE IT SETS OUTSIDE AGAIN IT WILL GET COWL VENTS. A 67 I BOUGHT HAD THEM ALREADY AND IS ALL ORIGINAL. ANYONE KNOW?

[49studebaker]

Originally Posted by 68speedalert

You're right about the side vents. However, with the factory a/c &/or heat systems, the cowl is where the air that the blower blows, comes in.

I've been considering shaving mine also but was worried about A/C vents. Just today I read on the forum that the Vintage Air A/C System doesn't use outside air. So with this in mind, I'm back to considering shaving the cowl and using part of the kick panel vent to submerge part of my speakers.

[Aarons72s]

davidh I dont think they were factory but dont quote me on it. As there are some rarely seen options out there but I think the screens/ trash guards are aftermarket.

[shifty]

I have seen people shave. The only thing I've heard on the topic is that you need to leave the cowl bolted in while cutting out and welding in or it will lose its shape. I've never seen a factory shaved cowl. I read that No Limit Engineering was probably selling a shaved setup for our trucks, but I have yet to see it. If it was out there and less than $200, I would buy it.

[Willy Prost]

There are screens that can be installed under the cowl opening. LMC has them, I'm sure one of our favorite board vendors have them also.

But just do what I did years ago and cut a piece of window screen to fit under the cowl opening.

I'm out of town right now, or I would go out and take a picture of what mine looks like installed.

[LawMan02]

I did the same in trying to head off future problems with leaves and such by making a screen for my truck. I used aluminum screen that I had left over from covering my gutters. Easy, cheap and seems to work great. I wish I had taken more pics.

[Bob B.]

Another problem that can have the same results as trash in the cowl drains is water leaks around the door hinges, top rear fender bolts, and rear cowl bolts. All these holes go into the 'A' pillar, the box section upright that goes from the roof all the way down to the rockers. There is no drain at all in the pillar, and water in it can eventually rust out the bottom inside the rocker. If it gets really bad in there, it can rust to he point that the lower door hinge comes off. The best fix is to use sealer around the hinges and the bolts that screw into the pillar. Also, if you have the front fenders off, remove that 1" plastic plug at the front of the rocker and you can see the bottom of the pillar in the rocker. Drill a hole in it, so the pillar will drain into the rocker (just be sure that your rocker drains are clear!).

[Draggn66]

Ok for those that have put some sort of screen under there....how did you attach it?

[Aarons72s]

If you buy the aftermarket ones they just atach to the stock locations. As for home made I am unsure.

[special-K]

If you "shave" the cowl vent area,water will still be getting in.

[shifty]

Originally Posted by special-K

If you "shave" the cowl vent area,water will still be getting in.

Water drains out. It's a problem of the debris getting through the cowl and accumulating in the area pictured holding moisture. Prevent the debris from gathering by shaving the cowl and you reduce the debris, reduce latent moisture, reduce rust.

[68C15]

Originally Posted by shifty

Prevent the debris from gathering by shaving the cowl and you reduce the debris, reduce latent moisture, reduce rust.

and hopefully snow. fine powdery snow goes right through the heater and covers the whole interior at times

I will have to do something soon. is there a way to shave the cowl yet allow fresh air for the stock heater?

[shifty]

If you look at the setup of the fan, I think the heater pulls its air from the area we're *****ing about having leaf/debris buildup in (the box shown in first and second posts)

[Aarons72s]

Originally Posted by shifty

If you look at the setup of the fan, I think the heater pulls its air from the area we're *****ing about having leaf/debris buildup in (the box shown in first and second posts)

Yup. And that fan shreds it nice and fine and blows it on you until the heat or a/c box fills up with leaves. Dont ask how I know about the last part.

[davidh]

Originally Posted by shifty

If you look at the setup of the fan, I think the heater pulls its air from the area we're *****ing about having leaf/debris buildup in (the box shown in first and second posts)

That funny. I remember changing a heater core out of a 69 and it blowing out crap every time I put on the defroster, leaves dirt twigs. I found it amusing really. I sold it a while later.