Firewall rustout

darth_linux

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Hi, on my '66 Newport, the passenger side of the cowl doesn't drain below the car like it should, it drains into the engine compartment, due to that area being rusted out. See photo below. Is this a structural concern, or more of just an annoyance? Thanks.

IMG_1858.jpg
 
I might suggest to discover the cause of the "no drain" issue first. Then you can braze-in some metal on the cowl area and close up that "drain" of sorts.

There was a thread on another forum about cleaning out the rocker panel drains and then coating the innards with a sealant material. I suggested an oil-based compound that would wick into the nicks and crannies of the structure and also be absorbed into any remaining debris, rather than an encapsulator compound which would seal it all.

A friend had a '70 'Cuda HEMI that he had to fix some rust issues in the cowl area, years ago. Not sure where it was on the cowl structure, but it seemed like it was toward the bottom on the rh side?

The cowl area is supposed to be one of the stiffest areas on the car body itself, from what I read years ago. FWIW.

Looks like you are making good progress toward a nice cruising season!

CBODY67
 
I might suggest to discover the cause of the "no drain" issue first. Then you can braze-in some metal on the cowl area and close up that "drain" of sorts.

There was a thread on another forum about cleaning out the rocker panel drains and then coating the innards with a sealant material. I suggested an oil-based compound that would wick into the nicks and crannies of the structure and also be absorbed into any remaining debris, rather than an encapsulator compound which would seal it all.

A friend had a '70 'Cuda HEMI that he had to fix some rust issues in the cowl area, years ago. Not sure where it was on the cowl structure, but it seemed like it was toward the bottom on the rh side?

The cowl area is supposed to be one of the stiffest areas on the car body itself, from what I read years ago. FWIW.

Looks like you are making good progress toward a nice cruising season!

CBODY67
Thank you!

To clarify, the water is draining out into the engine compartment before it can reach the proper drain holes down where the cowl vents fresh air into the passenger compartment.

I had the trim panels and vent doors off today, vacuumed out all of the debris and had Mrs. darth_linux pour water into the cowl. None of the water made it into that vent area so I'm deducing it all drained out into the engine compartment through that rusted out area.

It's odd to me: the driver's side doesn't have any rust on the firewall, and there is just a small amount of rust below the wiper motor.
 
Thanks for that information. Now, to effect a temporary closure of the perforations, put some duct tape securely over the perforated area and do the water test again, with more water, when the weather gets warm enough.

Take care,
CBODY67
 
Hi, on my '66 Newport, the passenger side of the cowl doesn't drain below the car like it should, it drains into the engine compartment, due to that area being rusted out. See photo below. Is this a structural concern, or more of just an annoyance? Thanks.

View attachment 582840
I think it would be hard for anyone to tell whether there was structural damage.
I recommend that you take off that wheel well.
I would take an exhaust cutoff wheel and cut out the rusted area above that pinch weld.
Then I would look in with a flashlight to see what damage is behind the firewall. I would hope that the body supports in the cowl are okay, but seeing is knowing.
Of course the final solution is to bend a new piece of sheet metal to fit the cut out area and weld it in place.
 
Such investigations might be a good use of a "borescope" or "Critter Cam" for more internal views.
 
That's a very common rust area on slab sides. Seeing that you are in the northwest, it was most likely caused by acidic pine needles collecting in that area of the cowl. I would not consider it a structural issue. I would cut it out and patch it to stop it from progressing further.

Jeff
 
That's a very common rust area on slab sides. Seeing that you are in the northwest, it was most likely caused by acidic pine needles collecting in that area of the cowl. I would not consider it a structural issue. I would cut it out and patch it to stop it from progressing further.

Jeff
Thank you for the info. The car is actually from Philly, and spent most of it's life near there, then later in Indiana, South Carolina, and then about 3 years ago it moved to Washington State. Everything got cleaned out 4 or so years ago when the car was painted, but who knows how much debris sat in that cowl and rotted things away, and for how long . . . if I ever have need to remove the hood, engine etc., I'll probably get that area patched. For now I think some industrial duct tape will serve to block it off and get the water draining where it's supposed to go instead of into the engine compartment.

thanks again!
 
Too bad you live so far away. I have two '66 T&C Wagons (Newport Trim) that I need to get rid of plus some '66 Newport parts including two doors. All will probably go to the scrap yard before the end of Summer. All are good for parts only. Restoration would not be practical at this point.
 
Too bad you live so far away. I have two '66 T&C Wagons (Newport Trim) that I need to get rid of plus some '66 Newport parts including two doors. All will probably go to the scrap yard before the end of Summer. All are good for parts only. Restoration would not be practical at this point.
a parts car would be nice to have, but too far away, and no where to put it :(
 
I think you should check the floor/firewall inside the car for moisture. The area of rust that you see connects to the floor pan. It’s spot welded and sealed at the factory. I’d check it out by removing the cowl panel, you won’t be able to clean everything out and reseal it any other way. Sealing it from the outside will still allow water to get into any rust you haven’t cut out. There will be rust there even if there’s no holes. This area needs to be resealed from one side to the other. The rust near the wiper motor is part of that. Take off the rubber flap and clean it out, it’s probably full of debris that is holding water. I don’t care how nice these cars are on the outside, this entire area needs to be checked/cleaned and resealed. You can also get to the bottom of the windshield seam from inside the cowl area. You’ll be surprised how easy it is to clean out. A blowgun or even a pressure washer would work well.

I had to make some repairs on my car here, it wasn’t bad and now I’m confident it will never be a problem again. After cleaning, making the repairs and sealing it, I coated everything with Eastwood’s inner frame spray the whole way down to where the water exits the car.

Just my 2 cents……. Every car out there needs to be checked and maintenance done here!!
 
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