Author Topic: Upper to Lower Cowl Sealant / Spot Weld  (Read 2192 times)

Offline CudaDownUnder

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Upper to Lower Cowl Sealant / Spot Weld
« on: December 13, 2011 - 01:36:28 AM »
Hi All,

I have removed the upper cowl section to attend to some rust issues on the upper and lower cowl sections. That's almost done now so I'm thinking ahead about how I'm going to weld in the replacement upper cowl.

When I removed the upper cowl is was clear that the factory applied sealant between the upper and lower cowls before spot welding the two together - see pic below

Has anyone tried to replicate this process? If so, please share your method and the outcome.


1973 Plymouth 'Cuda




Offline mopardave

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Re: Upper to Lower Cowl Sealant / Spot Weld
« Reply #1 on: December 13, 2011 - 09:06:55 AM »
i would use 3m panel bonder, IT is as strong as weld, seals, wont crack or shrink, and excess is sandable.  good stuff
Mopar Dave
Rosevillemoparts.com

if I haven't replied to your post or PM email me direct    dradcliffe@mikeriehls.com




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Offline CudaDownUnder

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Re: Upper to Lower Cowl Sealant / Spot Weld
« Reply #2 on: December 13, 2011 - 04:10:43 PM »
Thanks Dave,

I'll try and source some - it sounds like an excellent product.


Can anyone answer this...

How do I apply sealer, press the two pieces together and then spot weld it together without destroying the sealer? Like the factory did.
1973 Plymouth 'Cuda

Offline jimynick

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Re: Upper to Lower Cowl Sealant / Spot Weld
« Reply #3 on: December 13, 2011 - 04:40:22 PM »
I'm in bodyshops nearly every day and the only time I've heard of what you're asking was when I was told that the shop applied the bonding agent and with a $30,000, very high tech spot welder, did a few spots while the bonding was still wet. Apparently they'd tried it once it dried and it explodes. What I'm going to do with my cowl when I replace it, is leave a few drilled and ground spots for those welds (mig for me) and let the bond do the rest. Dave wasn't kidding when he said the bond will act as a seam sealer and I'm in the process of rounding up enough of the 3M product to do every seam on the damned rust magnet. That way, you don't need to sweat getting caught in the rain anymore.  :2cents: Ian

Offline Challenger III

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Re: Upper to Lower Cowl Sealant / Spot Weld
« Reply #4 on: December 13, 2011 - 06:30:09 PM »
I saw your post on my resto thread about this subject. Sorry for not getting back to you sooner!  :misbehaving:  I welded the cowl on with no sealer. I am using NP-1 through a length of flexible tube through the vent openings to seal. I'm not sure how a guy can replicate the "Factory Technique".
Mike    Yakima, Washington

Resto Thread:  http://www.cuda-challenger.com/cc/index.php?topic=66668.0

Offline CudaDownUnder

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Re: Upper to Lower Cowl Sealant / Spot Weld
« Reply #5 on: December 14, 2011 - 12:52:58 AM »
Thanks for your replies. :thumbsup:

It's either 3M panel bonder with a few spot welds or lots of spot welds & NP-1 through a long tube.
I'll investigate these two modern day options.

It still puzzles me how the factory did it though... maybe someone who worked on the assembly line will stumble across this thread and share the secret.

1973 Plymouth 'Cuda