TheSamba.com :: View topic - 3M 5200 Marine sealant for body under sealant repair?

Tue Dec 02, 2014 12:08 am

So I have a half tube of 5200 - a legendary marine sealant. I am planning to dig out some spots in the thick black factory coating under the body that are cracked, and reseal the spots. On my Syncro I used NAPA's grey body sealant.

Anybody use this stuff enough to say whether it would be a worthy product in this application. It's totally waterproof and approved for under the waterline use. It's tenacious as heck, UV stable, etc. I've only used it to seal deck fittings and the like but it seems tailor made to seal against water. Anyone disagree? Thanks.

Tue Dec 02, 2014 1:08 am

If your 5200 is still good and you use it on your vanagon, don't ever expect to be able to remove it. It sets like rock or rather very hard rubber. I would use a spray can of undercoat from your local parts store

Tue Dec 02, 2014 3:13 am

I have used polyurethane sealants that I can get from my local lumber yard for many uses including auto body.

Tue Dec 02, 2014 5:09 am

Wildthings wrote: I have used polyurethane sealants that I can get from my local lumber yard for many uses including auto body.

Me too.

Tue Dec 02, 2014 10:22 am

IdahoDoug wrote: So I have a half tube of 5200 - a legendary marine sealant. I am planning to dig out some spots in the thick black factory coating under the body that are cracked, and reseal the spots. On my Syncro I used NAPA's grey body sealant.

Anybody use this stuff enough to say whether it would be a worthy product in this application. It's totally waterproof and approved for under the waterline use. It's tenacious as heck, UV stable, etc. I've only used it to seal deck fittings and the like but it seems tailor made to seal against water. Anyone disagree? Thanks.

5200 is great stuff.... you'll need a plasma cuter to get it off :lol:

Tue Dec 02, 2014 10:51 am

I agree - an excellent product but overkill for what you have in mind.

I use it to seal the spokes on wire wheels so they can run w/o tubes. the stuff is great for that but would need a grinder if I ever wanted to remove it.

Tue Dec 02, 2014 11:45 am

Thanks! Went ahead and used it. The total area was about 5 inches of seam behind each rear wheel where I could pry the original black thick stuff up, and another area about an inch by two inches also in eash rear wheel well. I pried it up until I could see I was prying it off clean metal, then razor cut the edges, wire brushed and primed with self etching primer. Since it is cold here, I hit the areas with a heat gun to warm them before the 3 layers of primer, then left an electric heater on the spots for a half hour. Came back and spread the 5200 on each area with a popsicle stick. The tube turned out to be drying, so I punched a hole in the side and kneeled on it to blow fresh stuff out of the center. It gave its all for the Vanagon!!

We don't have much salt here, but I grew up in Michigan and am paranoid. The worst you can leave on a car is what I found - minor cracks in the old sealant so salty water gets in there, then cannot dry. Like a torture test. Now these spots are resealed against the corrosive sprays they use on the road bed and the odd bit of salt here and there. Looking forward to seeing how she goes with studded aggressive tread snows. Now all we need is the white stuff.

The front wheel wells are doing great. No cracking or missing chunks. This van has likely seen very little salt. It was in Germany for a couple years, then back in Georgia for the rest of its life. I hope to keep the body rustfree and living here it should not be difficult.

Tue Dec 02, 2014 8:13 pm

Doug, can I work as your apprentice for a year? I would learn so much good stuff :)

Tue Dec 02, 2014 8:54 pm

Yes, but don't bring the hightop when you come. They'll put me in jail for grand theft - auto. I would like to put a hightop on Mango some day. There's just not enough surface area for yellow and that would add 40% more by my reckoning.

Tue Dec 02, 2014 11:58 pm

Wouldn't you keep the inevitable high top white, as part of your theme?! :wink:

Wed Dec 03, 2014 9:07 am

Heh - yeah. I've seen a few high tops cleverly painted to minimize the visual height. I saved a couple pics somewhere. Definitely not all yellow though.