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Expanding foam in rocker panel?

Old 09-30-2015, 09:55 AM
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Default Expanding foam in rocker panel?

Yesterday I asked about 2x6 rocker panel replacement and a member suggested I do it by myself instead of getting a shop to do it. I'm the type of person to do stuff myself instead of getting others to, but in this case I have no choice due to not having a welder, nor any welding experience or even a buddy with one.

It got me thinking and I figured if I do end up buying a welder and start to learn how to do it, it might be a nice project to get into.. but my problem is that winter is coming fast here (north east), and the last thing I want is snow and salt doing more damage. I don't think I'll have the time before winter to get the sufficient funds and knowledge/experience to get into this. The major hole is only seen from under the panel and is less than 1/2" wide, but about 8-10 inches long. I can squeeze my fingers in there and if I pull it feels like I could rip a chunk off.

I doubt I'll be able to fix my issue before that time, so what I was wondering is if there's a temporary fix (until march-april) so I can limit/reduce the amount of salt getting inside my rockers. What I thought of is expanding foam, but I read it could actually do more damage by keeping moisture in. I also thought maybe put some bondo and paint over it with some type of rubberized paint. Keep in mind it's for about 6 months until I replace the whole thing with a 2x6.

Any suggestions is greatly appreciated!
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Old 09-30-2015, 10:20 AM
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You might want to look at using POR-15 w/fiberglass to do a temporary repair on it. (Actually applied properly POR-15 seals rust up really well and lasts a long time.) I would definitely not put expanding foam in there!
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Old 09-30-2015, 10:22 AM
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While expanding foam may seem like a good idea, it is not. As you stated, it will hold moisture longer than if it just wasn't there at all.

Your best bet would be to grind off the rust that is there and seal the bare metal from exposure. Then you would cover up the affected area and keep salt and sand from doing its thing until you are ready to properly do the repair/modification.
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Old 09-30-2015, 10:36 AM
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Originally Posted by Rambler65 View Post
You might want to look at using POR-15 w/fiberglass to do a temporary repair on it. (Actually applied properly POR-15 seals rust up really well and lasts a long time.) I would definitely not put expanding foam in there!
The consensus seems to be no expanding foam, so I'll forget about that idea.

I'll look into fiberglass and por-15.

Originally Posted by weswins View Post
While expanding foam may seem like a good idea, it is not. As you stated, it will hold moisture longer than if it just wasn't there at all.

Your best bet would be to grind off the rust that is there and seal the bare metal from exposure. Then you would cover up the affected area and keep salt and sand from doing its thing until you are ready to properly do the repair/modification.
I'll try to take a picture to show, but I'm afraid to just poke through the metal if I grind it as much as possible. Last summer I buffed the rockers, quarter panels and the bottom of doors in order to bedline the whole thing, and this rocker panel is the only one affected like this (rotted from the inside).

I wouldn't mind some rust on the outside and I'd be able to wait, but since I have no way to attach a mud flap in the front, all the snow and salt is going to go right in the hole I described, possibly affecting areas that are still intact today. I want to avoid that at all costs.
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Old 09-30-2015, 10:55 AM
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Just let it ride until you are ready to do the steel rockers. The cancer is already in there.
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Old 12-06-2015, 07:34 PM
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Also installed my brown dog mounts and 784 injectors. The mounts took about 3 hours. Had issuea lining up the passengers side. I was able to install the injectors without unhooking the fuel rail from the fuel line. The computer needs about 50 key cycles to re learn the injector parameters so i am not collecting and mileage data, but it does seem to pull harder at 3 to 4k rpms
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Old 12-06-2015, 08:38 PM
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Originally Posted by Cane View Post
I also thought maybe put some bondo and paint over it with some type of rubberized paint.
Bondo is not your friend. If you just want to keep water & salt out of it until you can get a proper repair done, try aluminum tape. Not duct tape, which is cloth backed, but the stuff that is really used for duct work, aluminum strips with a really, really good adhesive.

This stuff This stuff
.

Clean the area scrupulously, and tape that sucker up. Unless you hit gravel or a rock, it will still be in good shape come spring.

No, it won't look good, but it will do the job.
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Old 12-06-2015, 09:09 PM
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Originally Posted by XJlimitedx99 View Post
Just let it ride until you are ready to do the steel rockers. The cancer is already in there.
^^^ there's your answer. It really won't change much over a few months. You're going to hack it all off anyways.
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Old 12-07-2015, 01:03 AM
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I would just let it be tell you can fix it later in a few months.Anything you could do would be a bandaid and your gonna replace it soon so why waste your time or money?
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Old 12-07-2015, 02:51 AM
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Originally Posted by WyoCherokee View Post
Also installed my brown dog mounts and 784 injectors. The mounts took about 3 hours. Had issuea lining up the passengers side. I was able to install the injectors without unhooking the fuel rail from the fuel line. The computer needs about 50 key cycles to re learn the injector parameters so i am not collecting and mileage data, but it does seem to pull harder at 3 to 4k rpms

Dang, I was hoping it would learn after some mileage. 50 starts regardless of year? How long does it need to stay on?

+1 on aluminium tape. Maybe don't grind it down as much as possible but as even as you can get it. Just a wire brush and some light scraping if you're really worried? My rear doors have a fair bit of rot to them from very old, worn window seals. Do you know if this or another reason has caused your rust? If you end up waiting I'd at least try to solve the source of the problem ahead of getting it fixed.
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Old 12-07-2015, 02:59 AM
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A lack of under coating and road salt is why most rockers rust out.The floor pans can rust from the inside out the outside just depends where you live.
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Old 12-07-2015, 03:07 AM
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Ah, I just got lucky then. Either mine sat in a garage for a long time or some noble gentleman took the time to undercoat. I'm gonna be pulling the carpet soon, hopefully I won't end up with some of my own pics to post...
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Old 12-07-2015, 03:16 AM
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And depends where you live if they use salt on the roads,Some places it gets too cold for it and they use sand or other stuff.I live in kentucky below the rust belt and i have seen jeeps rusted out bad and i have seen them with zero rust.
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Old 12-07-2015, 03:32 AM
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I live in Maryland and salt is 100% an issue here. Once it starts to flurry there is consistently more salt than asphalt on the roads. I've never cared about a vehicle enough to power wash the undercarriage until now, and mine is rust free save for where the seals went bad and I plan to keep it that way.
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Old 12-08-2015, 09:16 PM
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Originally Posted by Kung Fuhrer View Post
I live in Maryland and salt is 100% an issue here. Once it starts to flurry there is consistently more salt than asphalt on the roads. I've never cared about a vehicle enough to power wash the undercarriage until now, and mine is rust free save for where the seals went bad and I plan to keep it that way.

Heh. First time I ever saw a PILE of salt in a gutter was up your way, at least a week after the snow was gone.

Somebody's buddy has the contract, I'm guessing.
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