Cowl Rust Repair Step-by-Step

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69 Rustang

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I am finally re-assembling my '72 Mustang after repairing the cowl rust. Here are the images step by step.

Teardown Begins, ready to drill some spot welds:

Cowl1.JPG


A look inside the cowl before taking the top off. Lots of rags stuffed into the cowl hat and heater to absorb water?

Cowl2.JPG


Dash and HVAC is removed, here is the cowl hat area from the bottom inside the car:

Cowl3.JPG


The cowl top is off, here is the hat. Nice tin patch you can see from here.

Cowl4.JPG


I pulled a huge fiberglass patch out and it left these holes:

Cowl5.JPG


Cleaned up, cut a nice shaped hole, and ready to weld in the first patch:

Cowl6.JPG


The first patch welded in. Hmmm, do I really need a heater in California? Oh yeah, it is the A/C I want to work again... Time to cut another hole!

Cowl7.JPG


Hole and new "Hat" in place. Went to a local sheet metal shop and for $20 they rolled a edge onto a piece that became the "hat".

Cowl8.JPG


After some priming and paint, the cover is glued on using panel bonding adhesive. Welds were done on the ends and on the butt-weld/seam (after this pic).

Cowl9.JPG


Welding complete, finishing the welds with some filler. Had a near major disaster during this phase as welding sparks started a piece of cardboard under the car on fire. Thought for a few minutes I was going to lose the house as the fire was really going before I noticed. The only real damage was to the dashboard that was under the car--now I need a wiper knob and bezel--if you have one PM me.

Cowl10.JPG


Paint complete, and reassembly is underway.

Cowl11.JPG


 

downwardspiral

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nice work.. glad to see the house didnt burn down lol

 

mach71351c

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Nice job. You will be telling this story for a while.

 

droptop73

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Nice work! In Michigan we'd call your starting point "rust free".

 

Danno

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I am finally re-assembling my '72 Mustang after repairing the cowl rust. Here are the images step by step.

Teardown Begins, ready to drill some spot welds:

Cowl1.JPG


A look inside the cowl before taking the top off. Lots of rags stuffed into the cowl hat and heater to absorb water?

Cowl2.JPG


Dash and HVAC is removed, here is the cowl hat area from the bottom inside the car:

Cowl3.JPG


The cowl top is off, here is the hat. Nice tin patch you can see from here.

Cowl4.JPG


I pulled a huge fiberglass patch out and it left these holes:

Cowl5.JPG


Cleaned up, cut a nice shaped hole, and ready to weld in the first patch:

Cowl6.JPG


The first patch welded in. Hmmm, do I really need a heater in California? Oh yeah, it is the A/C I want to work again... Time to cut another hole!

Cowl7.JPG


Hole and new "Hat" in place. Went to a local sheet metal shop and for $20 they rolled a edge onto a piece that became the "hat".

Cowl8.JPG


After some priming and paint, the cover is glued on using panel bonding adhesive. Welds were done on the ends and on the butt-weld/seam (after this pic).

Cowl9.JPG


Welding complete, finishing the welds with some filler. Had a near major disaster during this phase as welding sparks started a piece of cardboard under the car on fire. Thought for a few minutes I was going to lose the house as the fire was really going before I noticed. The only real damage was to the dashboard that was under the car--now I need a wiper knob and bezel--if you have one PM me.

Cowl10.JPG


Paint complete, and reassembly is underway.

Cowl11.JPG
I have a 72 fastback that looks like what you started with. I am going to try to do a fiberglass bandaid/sheetmetal repair from the bottom and from inside the right hand cowl opening in front of the windshield. I have the interior gutted, i.e. dash, seats, and HVAC unit. I think I can do a quick and dirty repair that may last for a little while. If I keep the car I will do the real repair, and yours looks like what I would try.

You basically removed the rt fender and cut out above the hat, correct?

Then with that opened up you cut out the tophat and surrounding material, fabricated a new hat etc and put it allback together. Can this be done with the windshield and hood in place? I have toyed with the jdea of just blocking that opening, but that is the only vent on this A/C car. The A/C is inop too, too many parts missing and or removed. Luckily this is the only rust I have, but it is enough!

 

OMS

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Complete cowl is now available 420.00

When he did the repair there was no parts being made for it.

 

shafe

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Great job I have to do the same thing (glad dynacorn makes the part now)

 

Duncan Mach72

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@ Danno - it's only 4 bolts to remove the hood! I hope it's ok to leave the windshield in place, can't see why not.

I need to do mine eventually. At present I have a fabricated panel, with welded hat, secured from underneath with self tappers & a lot of sealer. It almost works...

When doing the job I drove to a local car show without heater box or glovebox fitted - oh look I can see the cylinder head thru here...

O/t - I recall there was a guy there with a General Lee tribute Charger. This is in the UK!

 
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