Sealant for fuel tank cover

[keith]

Hi All,
I'm in the middle of rewiring my 23SF and I took the fuel tank cover off to try to find places to run wires (which didn't work out). The previous owner sealed the cover down with silicone, lots of silicone. Since it is a possible intrusion point that would lead directly to the fuel tank I wanted to seal it again but with something besides silicone. Any suggestions?

[FishStretcher]

Clean it really well, wipe it with acetone- not alcohol (this is important). Scuff the bond line with at least a scotch brite pad. Wipe with acetone again. Then use 3M 4200 or 5200. There are differences in cure time and ultimately the adhesion. If you prep well, then I think the 4200 will work well for you. But you have to work fast if it is a warm humid day.

Retail is usually $16-20 for a 10 oz tube. If you look, sometimes you can get it for $13 or so. If you are in a hurry, you can pay $23 for 3oz!. Jamestown distributors had a special a little while ago- and it looks like they are still running it.

http://www.jamestowndistributors.com...hesive+Sealant

That's what I did on my fuel tank hatch. Although I didn't prep as well, as I knew I'd be digging back in there to recore the hatch this year.

[keith]

Thanks FishStretcher. That sounds like a good plan to me. I don't have a lot of experience with the 4200. I will be able to get the hatch off again without breaking it right?
Also, I live in California. We don't know what humidity is.

[FishStretcher]

I have heard complaints about 5200 pulling up gelcoat. Personally I have never had that issue. I think that using 5200 over an old silicone joint is weaker than a carefully prepped joint. As the silicone leaves a release agent. The 4200 is a bit lower strength and faster cure so it might be what you want. Again, I don't have a problem removing it. But it sure doesn't peel up like silicone.

To properly address your concern: you won't break the hatch removing it, but it might lift some gelcoat down in the bond line.

[Old'sCool]

I would suggest 4200. 5200 is a polyurethane adhesive. You dont need adhesive qualities with a hatch thats screwed down.

[FAS]

3m 5200 is listed as permanent adhesive sealant,4200 is more forgiving and is removable.both are gonna be tough to remove.8 ft of 5200 down each side is gonna give you a problem to remove.lotsa stuff out there.. polyseamseal? I will use a white pure silicone on mine,just to be able to raise the deck if needed.

[gofastsandman]

GE silicone or boat life caulk would be my choice. Take some 100# mono and tack it down
first. Let it dry and caulk as usual. Next time the hatch has to come out, just pull the mono out like a zipper. 4200 and 5200 are the devil`s spawn.

[keith]

Originally Posted by gofastsandman

GE silicone or boat life caulk would be my choice. Take some 100# mono and tack it down
first. Let it dry and caulk as usual. Next time the hatch has to come out, just pull the mono out like a zipper. 4200 and 5200 are the devil`s spawn.

I like the 100# mono idea, thanks! I will use that one for sure. I'll also check out life caulk.

[deepsushi]

I would recommend life seal for your hatch. Its a great sealant and it wont yellow in the sun. You only need a sealant for the hatch as it is held down mechanically with screws.

You or the future owner will be cursing the world if you choose 5200 if you ever have to remove the hatch!

[Chaser]

4000UV will stay white better than 4200, plus it pulls and cleans up better.

Whatever you do don't use 5200!!!

For my floor panels I plan to use a compressible foam strip on the flange that the panel will sit on. I'll screw the panel down on top of the foam strip, and then fill the gap on the edge with 4000UV to seal it. That way, when I need to pull it up, its just the seal that needs to be scraped out, and the hatch will not be adhered to the flange on the bottom. Gluing it in on the bottom is asking for damage if you have to remove it at a later date.