Partial cowl repair possible?

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RIBS

Well-known member
Joined
Jun 9, 2021
Messages
763
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Location
Metro Atlanta
My Car
1971 Sprint Tribute 302 C4 Convertible
Hi all,

 I am going through the 71 Mustang convertible I bought 4 months ago, I finally got the fenders off and did a cowl leak test. The passenger side Is bone dry but the water came straight in the drivers footwell.  It’s coming in from the far front corner, in-line with emergency brake and headlight dimmer.   As far as I can tell, it’s an area about the size of a golf ball that needs attention.

My question is,  anyone to a partial repair?  my budget can’t handle the expense of tearing the cowl out.My thought is, cut the corner off and get a repair in through the space marked in pic….my welder is coming to do quarter panel next week, might have him cut this corner off for inspection…

opinions?

C881AFAC-D24B-4D81-B5B9-A310734D21BE.jpeg

 
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Hi,

It can be done I guess but you are proposing a very small hole to work through. I am currently working both sides of my cowl and am cutting the corners off to get good access to the inside. I also found more rust than I bargained for...

Good luck!

Vincent.

 
The problem is the side upper frame is welded over the cowl cover….

 
I know, it's 50% of the pain when there is actually not neccesarily a problem with that part... I removed mine to get inside the cowl:

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...

 
I removed the entire top of my cowl.  The passenger side was shot above the heater/ac box.  I'm glad I took the top off instead of trying to do a partial area repair.  Yes it takes time and a lot of work plus the windshield needs to come out but to me it was worth it.  I know that my cowl is solid and rust free.   Looks can be deceiving.

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The bottom side of the top of cowl was loaded with rust.  

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I just bought a 72 mach1 survivor, and even the though cowl looks pretty decent (I can still see factory paint in it and only some minor rust), I have a very small water leak coming down the heater box on the passenger side.

Is it more likely than not that I have pin hole rust spot inside the bottom cowl ?

Screenshot 2024-09-28 at 5.42.22 PM.png
 
I just bought a 72 mach1 survivor, and even the though cowl looks pretty decent (I can still see factory paint in it and only some minor rust), I have a very small water leak coming down the heater box on the passenger side.

Is it more likely than not that I have pin hole rust spot inside the bottom cowl ?

View attachment 93501
I’d say yes. Many of our cars get leaks there.
 
Unfortunately, I did not have a choice in replacing my upper and lower cowling. Look at the state of it, that's UK weather for you. The upper and lower cowling was totally replaced but it meant a lot of equipment had to be removed. It was worth it in the end.

I think yours can be saved if its only that small area and paint the whole lot with a rust converter and then under coat it with a good metal protector.
Good Luck
 

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Glad this resurfaced. One of the reasons I’m considering removing my dash was to inspect that area.
So, is it accessible from the interior? I believe I’m in good shape but, the fact remains the car sat for 3 years, unloved and uncared for by the previous owner. The fact rodents turned it into a tenement has me worried. Again there’s the caveat this is never going to see adverse weather but you can’t plan a pop up thunderstorm along our coast creating some havoc if we’re out enjoying a Saturday or Sunday drive.
 
Glad this resurfaced. One of the reasons I’m considering removing my dash was to inspect that area.
So, is it accessible from the interior? I believe I’m in good shape but, the fact remains the car sat for 3 years, unloved and uncared for by the previous owner. The fact rodents turned it into a tenement has me worried. Again there’s the caveat this is never going to see adverse weather but you can’t plan a pop up thunderstorm along our coast creating some havoc if we’re out enjoying a Saturday or Sunday drive.
@tony-muscle Did a comprehensive write up on how to repair the cowl from inside the car without removing the cowl or the heater core.

I'm probably going to try this method, since my leak is very small

https://7173mustangs.com/threads/my-method-for-cowl-repair.30508/#post-331697
 
@tony-muscle Did a comprehensive write up on how to repair the cowl from inside the car without removing the cowl or the heater core.

I'm probably going to try this method, since my leak is very small

https://7173mustangs.com/threads/my-method-for-cowl-repair.30508/#post-331697
Yes I did. It was a fun project (spoiler: it was not until it was completed!) It needed a lot of contortionism with tools, hands and arms but it is very doable with time and patience.

This takes you to my first post: https://7173mustangs.com/threads/my-method-for-cowl-repair.30508
 
Yes I did. It was a fun project (spoiler: it was not until it was completed!) It needed a lot of contortionism with tools, hands and arms but it is very doable with time and patience.

This takes you to my first post: https://7173mustangs.com/threads/my-method-for-cowl-repair.30508
Tony, I was planning on converting one of my two cars from FMX to Manual, and this would entail removing the dash board to install the pedal assembly. I've removed the dash from a 2007 Nissan and it was not an easy task. What's the level of difficulty for the 71-73 dash w/AC? I could try the cowl repair when the dash is out, but I'm slightly worried about tearing stuff up and not being able to get it back to stock
 
After I confirmed it was the cowl leaking on my ‘72, I approached this very similar to The Heff’s first cut picture. Mine was only leaking on the passenger side. So, I cut further toward center than he did to minimize the area I had to weld/finish. I cut into the right side access hole in the cowl top allowing full access to remove, fabricate, weld in place new parts at the hat/lower area, and reinstalled the original top. When I did this, there weren’t any aftermarket parts available so I had to fabricate the lower cowl and hat. It wasn’t all that hard, just a lot of work. The major costs were a new windshield, a tube of 2K seam sealer, some paint, and a little bit of sheet metal for fabrication.
 
I have seen plastic hats for replacing the rusted out one, and these are just glued in place with silicon sealer. The repair kit I had involved cutting out the old one from underneath and glue the new one up from underneath. It had a large square collar plate around the base, probably 2 inches all the way round, and you trimmed it to suit your cut out. My cowling was way passed repairing so I opted for a total replacement, upper and lower.

One thing does puzzle me is, what stops flying insects from being sucked down through the fresh air inlet hat, chopped up by the fan and blown out through the vents into your face. Was there at one time a fabric filter that was placed over the top of the fresh air inlet hat to stop this from happening? I was debating whether to stretch a pair of the wife's stockings over the top of the hat so it acts like a filter. It is accessible to do this via the two removable plastic grills covers.
 
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