APB - Check your cowl seam seals!

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WFO

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I'd be afraid to use Flex Seal, or anything else "As Seen on TV".
 

Goldie Driver

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I'd be afraid to use Flex Seal, or anything else "As Seen on TV".

"I sawed this boat in half !! " :eek:

:dogpile:


I would try it - the Flex Seal, not sawing the boat in half, especially since I don't have a boat, and whomever's I borrowed would probably be pissed ...
 

peats

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on my 81c10 i just laid 2 layers of fiberglass spanning the seam, then topped it with 2 layers of bed liner. it seems like a sturdy seal.
 

toddc72

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Are 73 K10 notorious for this too? Rest of truck is pretty much rusted bad in the wheel well areas and right where front fenders meet the cab in the corners at the very bottom. I doubt if water collection there anymore. Truck is used for my winter beater and bought it that way. Rest of truck seems dry but only drive it this winter and just got it after Christmas this year and drove it a few times because of snow. So I should look at it too or just don't worry about it because of how bad the rust is anyway? Thanks
 

80BrownK10

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Are 73 K10 notorious for this too? Rest of truck is pretty much rusted bad in the wheel well areas and right where front fenders meet the cab in the corners at the very bottom. I doubt if water collection there anymore. Truck is used for my winter beater and bought it that way. Rest of truck seems dry but only drive it this winter and just got it after Christmas this year and drove it a few times because of snow. So I should look at it too or just don't worry about it because of how bad the rust is anyway? Thanks
Yep a 73 is the same construction as the 73-80 series and the 81-87 models are basically the same design, cowl area is just a bit different die to the sperate hood and cowl area.

Look at it. I am sure you have some water getting through somewhere.
 

Brian J

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Thanks for the heads up on this. I took my cowl cover off yesterday and sure nuff, the seam sealer is cracked in several places. Guess that explains the holes in the passenger floorboard. Definitely should have been welded at the factory.
 

toddc72

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Yep a 73 is the same construction as the 73-80 series and the 81-87 models are basically the same design, cowl area is just a bit different die to the sperate hood and cowl area.

Look at it. I am sure you have some water getting through somewhere.


Thank you. I will maybe take a look this weekend than since truck is parked till winter and now would probably be the time to fix it if so BEFORE I need it again. Thanks
 

MikeB

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GM used seam sealer on this area but with time the sealer dries out, cracks, and begins to let water into the seam between the two sheets of metal.

On my 82, they did a terrible job with the seam sealer in some areas, allowing water to drip down behind the fuse panel. That eventually caused rust to develop on the fuse connectors, and rusted out the bottom of the kick panels. It's fixed now, but all that trouble because of some GM assembly guy who didn't use enough seam sealer in some areas.

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MikeB

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I suggest scraping out the old seam sealer as much as possible, and then cleaning the area to be repaired with wax and grease remover (AKA Prep solve). Then lay down a wide bead of good quality seam sealer. This SEM product has worked well for me.

https://www.semproducts.com/product/1k-seam-sealers/29392

It comes with a nozzle, and I bought a bag of extra nozzles on Amazon.
https://www.amazon.com/GooChan-20-Pack-Caulk-Nozzles-White/dp/B074RGZ1BJ/ref=sr_1_2?dchild=1&keywords=GooChan+20-Pack+Caulk+Nozzles+(White+/+20+Pcs)&qid=1592917123&s=hi&sr=1-2
 

eskimomann209

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I used construction adhesive. I think it was gorilla or lock tite. Hardest part is getting the edges closest to the fender area.
Also construction adhesive doesn’t “smear” well so if you’re used to caulking it’s NOT like that. It’s more like urathane sealer.
 

80BrownK10

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On my 82, they did a terrible job with the seam sealer in some areas, allowing water to drip down behind the fuse panel. That eventually caused rust to develop on the fuse connectors, and rusted out the bottom of the kick panels. It's fixed now, but all that trouble because of some GM assembly guy who didn't use enough seam sealer in some areas.

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Is that what the factory sealer looks like? If that's the case mine had already been re sealed at some point. I had big floppy gobs out of like a caulk gun tube type. I was thinking GM brush the sealer on. The stuff I reapplied was out of a tube as well. AC Delco medium sealer.
 

da_raabi

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Sumbsih had better be sealed up now. POR-15 Metal Prep, POR-15 paint, 2 coats of seam sealer, and 2 coats of Flex Seal.

Flex Seal is nifty stuff. Smells a bit like menthol, but it brushes on nice and self-levels like a dream.

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80BrownK10

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I think the best idea might be to rough it up, do all the previous things and fiber glass that whole area with matt and resin.
 

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