Cowl Vent Issue

[robbz28]

I knew that my cowl vent was in need of repair, I just want sure how bad until today. I took the air conditioning unit out of my car and the passenger side was actually not that bad, perfect candidate for the little plastic hats. But today I removed the fresh air vent and OH MY GOD! It is rusted out so bad all of the studs that held the vent in place fell off. No plastic hat is going to fix this!
I know about the proper fix of drilling out the welds and replacing those areas, but I want to avoid doing that if possible...so here's my idea. Cutting out the additional rust fron underneath the dash, then buying one of those metal patches that you are supposed to install from the top...trimming it to fit my needs and then coating it in POR and sealing it and tacking it from beneath the dash. Anyone done this? Any thoughts?

 

[chris66dad]

This might be an easier solution
Boyd's Mustang: Cowl repair

 

[robbz28]

I have thought about doing it that way...would definately be a lot less spot welds to cut out and wouldnt have to worry about the structural integrity of the car as much. I still think I can fix it from beneath the dash without having to cut the top. I know it wont be as good of a fix, but its better than nothing. I am also just considering welding up the hole completely because I have a/c, i dont need the vent. I am trying to do something cheap but effective and anything dealing with the top of the cowl is going to cost me. I got a baby on the way and just had to spend 1000 bucks on a tree that fell down in my yard...

 

[72mustang]

I had a few rust holes in my cowl also I used {Automotive Goop} and some really sticky fingers and I fixed the problem.I know this is not the best way to do it, but right now was not the time for me to go in and do all the cutting.I plan on doing the right fix eventually but for right now this has to do.I put the garden hose in the vent full pressure and no water is coming in.

 

[Az Pete]

Just be sure to weld it in good as the cowl is part of the structural integrity in our frameless cars.

 

[robbz28]

I have my car reinforced, drivers and passenger torque boxes and have a set of subframe connectors just waiting to be welded in. Put my new vintage air gen IV unit it yesterday (underdash portion anyway). And it came with a plug to plug up the cowl vent hole on the passenger side. I got a big piece of flat sheetmetal I think I am going to just cap off the drivers side with. I'll fix it properly later.

 

[chris66dad]

You could also use a plastic cowl vent cover for when you wash the car, drive in the rain or park it. It will keep most of the water out.
I was lucky because mine was not rusted. I did "tin can" the ends under the fenders and painted and seam sealed everything. Here are pics and a write up : Cowl Repair

 

[tx65coupe]

Mine occasionally leaks a little at the driver side vent. Its not all rusted out though. We repaired it several years ago, and it didn't leak. A few years ago it started again. I'm not worried about it. It takes alot of water for it to leak.

I have this cowl cover. Its the best one I have found. I use if the car has to be out in the rain or if there are tons of leaves and tree debris to worry about.

COWL COVER USA 1964-1966 - CJ Pony Parts, Inc.

 

[Bitter]

I did everything I could to avoid a full cowl replacement. In the end, I had plastic hats covered in sealant and butchered partial panels. I ultimately drilled out the spot welds and did it right. I'm not discouraging you from trying it. Perhaps you'll have better luck than I did. However my experience was that they don't follow the contours of the old cowl well even after being trimmed.

 

[Az Pete]

FYI...My cowl has been replaced but I use a strip of magnetic sign material a bit larger than my cowl to keep the trash out. Car lives outside. Cost...$5 and it has been speed tested for the heck of it up to around 70mph.

 

[robbz28]

I have seriously considered the magnetic approach, but one other thing I have considered is just shaving the cowl vents completely (as I won't need them at all on the car) My a/c does not use the vent, and with a/c I won't need the fresh air vent on my drivers side...If i need a little fresh air I will roll down a window. I am doing a "resto-mod" anyway, I have never seen one with a shaved cowl, might be a neat approach. The car is not going to have any of the emblems on it, antenna, no wheel well moldings, the only thing sticking up off of the car is the drivers mirror and the door handles (not shaving them because I have had shaved door handles b4, can be a pain)...

 

[tx65coupe]

I've seen the shaved cowl and think it looks wierd. A guy I know has that doen on his 68. He says that his fresh air vents still kinda work. I like being able to use the fresh air vents under the dash. I would not eliminate them.

 

[Az Pete]

I have seen a couple of cars where the cowl was filled on. I did not like the look at all. Part of it is that it is different and part is the fact that the area is pretty big for nothing to be there...

You will still get a small amount of air thru the drain areas in the corners under the fender.

 

[robbz28]

I can see where it would look funny because the area is so big, a car with a smaller cowl area wouldnt look as bad. I am going to get under my dash this weekend and tinker on it, I am thinking about doing the "tin can" approach, but with some fiberglass involved....it won't be pretty, but hopefully effective until one day I can do it properly.