Air Vents Pouring Water!

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Ricks70Duster340

Ricks70Duster340

Child of the King
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I put a hose into the cowl vent so I could clean out the drain holes. Lots of garbage came out from both sides! All of my older cars had this issue, so not unexpected. What was unexpected was that after I spent about 30 minutes cleaning out the drains, I saw the floorboards on both sides were full of water. None of the cars I had in the past with fresh air vents had that much of an issue with water pouring in from the vents.

I expected the first time I opened the fresh air doors that garbage would blow out at highwat speeds... and it did! Is there a secret I don't know about to ensuring the drain holes are really clear so this does not happen again during a rainstorm?
 
One problem is build up of leaves, mud and other debri on the cowl floor, which simply will not drain. It raises the cowl "floor" so that as water pools up, it runs over the top of the vent sleeves. Also of course, the cowl floor can rust through. You may know the drains are in the ends of the cowl, and they are not very big. "If I had the fenders off" I would be tempted to make them larger
 
There is only a 1 to 2 inch lip at the top of the vent intakes. Next time don't put as much water into the grill as you did.

As for keeping the drains in the cowel open, since we are not mind readers I'm going to assume you have a 67 dart convertible. There are drains built in on either side of the cowel visible when the fenders are off. Make sure they are open before you turn on the hose.

On another note. You might have rust at the bottom of the cowel at the vent openings OR anywhere else up there that let the water in.

Two people and a light trickle of water can help find where it is comming from.
 
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67Dart273 said:
One problem is build up of leaves, mud and other debri on the cowl floor, which simply will not drain. It raises the cowl "floor" so that as water pools up, it runs over the top of the vent sleeves. Also of course, the cowl floor can rust through. You may know the drains are in the ends of the cowl, and they are not very big. "If I had the fenders off" I would be tempted to make them larger
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Funny, I see you are from Idaho. This car was originally from Idaho. When I opened the air doors, the garbage the came out was definitely not from South Texas! I saw chunks of foliage that I've never seen her before. Guess it's been in there for a VERY long time!!!
 
Dana67Dart said:
There is only a 1 to 2 inch lip at the top of the vent intakes. Next time don't put as much water into the grill as you did.

As for keeping the drains in the cowel open, since we are not mind readers I'm going to assume you have a 67 dart convertible. There are drains built in on either side of the cowel visible when the hood is up. Make sure they are open before you turn on the hose.

On another note. You might have rust at the bottom of the cowel at the vent openings OR anywhere else up there that let the water in.

Two people and a light trickle of water can help find where it is comming from.
Click to expand...
Yeah, I used to think the trunk leaks were the bain, but this was way worse than that! Ugh. I can only imagine what would happen if I had to drive in a driving rainstorm! Batten down the hatches, dive, dive, dive!!!
 
I had the same problem. I had to remove my airbox and heater box (which was coming out anyway so you can skip pulling the heat box but its easier) and pulled and vacuumed all the crap out of the cowl then used air and blew everything in the center to the ends and repeated. The drain holes was easier for me to clear because my fenders where off. But that's how I did it I have some pictures and a video I will find them and post it uo here
 
The lip at the top of the air vent opening can be a problem spot for rust. Feel around carefully, you might be able to feel rust or pitted up metal/
 
Drains,
2001-06-23_004.jpg



Alan
 
If the lower plenum is rotted out around the air inlet standpipes, a lot of people end up doing major sheetmetal surgery in this area. The lower cowl plenum is available new from AMD as well as the upper cowl panel. If your into drilling spotwelds and reusing rust free vintage tin, theres several members here that drill apart dry area cars and sell the steel.

To repair this by replacing a rotted lower plenum you have to remove the hood, fenders, everything off the firewall including brake pedal, and steering column, windshield, and dash frame. At this point you can start removing spotwelds. Being that welding is involved to put it all back together, I also recommend taking the front seats and front carpet out.

The A pillars splice in at the corners with spot welds and lead filler. Just heat the lead with a torch and brush it out of the joints on either side with a wire brush. You can buy a lower plenum and splice in what you need, but as far as you will have to take it apart to splice it, you would be better off just changing it out.

Theres tooling holes that line all this stuff up. This aided in factory assembly, and will still work for a DIYer.

Hope this helps
Matt
 
If you drove in a driving rainstorm most of the water wouldn’t land on the flat surfaces of the car, so it would be just fine.
 
413 said:
If you drove in a driving rainstorm most of the water wouldn’t land on the flat surfaces of the car, so it would be just fine
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Not with the top down!

We still don't know what car you are working on. Just because your handle sugests a 70 duster doesn't mean that is what you are working on.
 
Debris that goes through the drains at ends of cowl falls to behind dog leg section of front fenders. Those opening get clogged also. Fenders rust. If you dont have a rocker trim molding you can remove a couple of body bolts and pull outward on the fender a little. All of B'cudas had spacer washers for panel alignment between fender and rocker. Have to put those back where they came from. 73 Valiant had rocker trim. Couldn't pull out on that fender.
 
I have a 2 foot long metal tube air blower with an angled end. I use that in most places to get rid of leaves and crap.
 
Thanks guys. Lots of good ideas. I am not a body man, so won't be taking the cowling apart. Hopefully not too much rust. Car won't be seeing many rainy days, as it sleeps in my garage and not under the stars!
 
You could install The air horns from the bottom In some cases without having to paint the car

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could try cleaning it out i remember stuffing a shop vac hose up the vents inside the car while blowing air through the cowl vents outside the car. I did have my fenders off and made sure the drains were clear.
 
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