Sealing tank hatch

[nipper]

I removed the tank cover from my 1991 V20 cuddy last year when I had a fuel problem. I put it back on without using new caulk. My tank hatch is in great shape with no moisture or flex whatsoever. I pulled it off yesterday so that I could put down new caulk. I scraped off all of the old caulk which was still stuck on very well. I was pleased to see the tank and all fittings, hoses, etc. were in very good shape.

What caulk/sealant should I use to put the hatch cover back on? Should I put the caulk down, then put the hatch over it or should I just put the hatch on then caulk from the outside (or both).

[Seacrets]

I'd do both, but don't use 5200. Find a good silicone caulk for above waterline use. Clean up all edges before applying.

[macojoe]

I agree, 5200 will stick forever and you may want to get back in there? I used that boat life stuff, did a good job and will come off if I need to get back in there again.
And yes put a bead down, drop cover on and do it again be sealed perfect!!

[tsubaki]

[nipper]

Thanks Tsubaki. Drinking already, huh.

[phester]

just did my hatch cover as well. I ran a healthy bead around the floor, then dumped the cover on and hit it again. The material I used was the 3m 4000UV fast cure. I'm sure any compatible chaulk is fine I would just make sure it is UV tolerant.

[spareparts]

i really like teh 4000, the new boats we sell use it on anything, it holds up well

[lumberslinger178]

When the mechanic did mine he used a clear silicone and it looks great , I think he must have used a squeegie cause it came out perfect.

[randlemanboater]

I used the 3M Marine Silicon, which is clear. It works real good, and easy the make look good.