Sealing old(er) aluminium hull?

(We don't seem to have a forum for restoring metal boats and a search didn't turn up anything so I guess this is the best place to post this question....)

I have a 1966 Lone Star 24 foot riveted aluminium cabin cruiser that seems to seep water. The construction of the boat makes it difficult to tell if the water seeps in from one place or many and bucking up the rivets (in some places) is nearly impossible.

The boat very much needs new exterior hull paint so I was thinking of having it soda blasted and that would be a good time to apply some kind of exterior sealant (after I get the buckets of silicon seal off!) but there are so many products on the market that claim to be "wonderful" and "amazing" and each one has their fans but ..... hear-say doesn't cut it.

I need a sealant thin enough to wick into joints and seal up small "cracks", something that stays flexible (so it doesn't leak again), and something that doesn't require heat (since I don't know what caulking the builder used and I don't want to make the problem worse).

5200 seems to come highly recommended and everybody sings the praises of Gluvit but there are some serious detractors who say it doesn't last.

Experience? Comments?

 

This product link may help.: http://www.3m.com/product/information/Marine-101-Sealant.html

 

Have you looked into Cold Tar Epoxy?

 

Wow! Coal tar epoxy looks like an effective seal for ANY leaky metal boat! It has its drawbacks but sure has its strengths.

 

Possibly West's G/flex.

 

I did my aluminum a year ago and the coal tar is still mint, no leaks.

 

I'd be interested in hearing what sealant you went with. I have a 1950's Lone Star Cruise Master aluminum boat that leaks (probably through the rivets) so I've been reading about various solutions to the problem. I've seen everything from mechanical tightening (i.e., pounding the rivets) to applying epoxy inside then heating from the outside to welding all the seams. Some of those sound like a lot of work, especially if an external sealant works OK. What is your experience?

 

Truck bed liner works well on a clean, toothed surface. Coal tar epoxy wouldn't be anything close to the top of the list.

 

aluminum filled MCU coating - google aluthane. However cannot be shipped outside the USA

paul

 

Awe, if you soda blast it clean then prime it with zinc chromate primer, then paint with a good epoxy 2 coats. Then a good marine paint . Coal tar epoxy not necessary, but sanding /blasting and priming with zinc chromate is. Best if you can do inside and out.

 

Polyurea hot spray seems like a certain fix, even if it didn't stick in some places.

 

GLUVIT Waterproof epoxy sealer

 

Interesting, what is it? Any brand names at hand?

 

Ive seen Belzona products used to repair various metal components like tanks. Dont know much about it. You might research.

http://www.belzona.com/applications/tanks.aspx

 

http://liners.rhinolinings.com/en/p/home

http://www.linex.com/pages/2010/bedliners/linex_vs_others/