Deck Seal

[Uncle Dave]

I am about ready to redeck my Sylvan (21' alum). It was not sealed at the factory. At least where the edge of the deck meets the alum sides. Any water went into the inner liner. There is about a 1/2 to 1" gap at most places. It was covered by carpet so not readily noticable. Any ideas on how to seal this?<br />Silicone II maybe?

 

[gewf631]

Re: Deck Seal

A gap of 1" between the edge of the wood and the side? Didn't get the wood cut to the right dimension, or was this by design?<br /><br />I've heard of guys using old bicycle inner tubes to fill the gap, but to me, this almost sounds like the perfect, self-draining, floor - instead of water running the length of the boat, it can just head out the side, then out the bilge.<br /><br />If your worried about things falling through the gap, why not just run the carpet a few inches up the side? A little adhesive, and the stiffness of the carpet, should make a decent transition. Or use that rubber molding (base cove) - it's cheap, comes in different colors, and should be flexible enough to conform.<br /><br />Good luck!

 

[ED21]

Re: Deck Seal

I tend to agree w/ Ed F about leaving it open. But the edges should be sealed to keep water out of the wood.<br />If you caulk the seam, first press in backer rod. It's a closed cell flexible foam rod that comes in various diameters used in building trade.<br />I think I would use polysulfide caulk instead of silicone. Not familiar w/ silicone II.

 

[Uncle Dave]

Re: Deck Seal

Thanks, Ed and Ed.<br /><br />The achellies heel of this boat is water was allowed into the inner liner. (old story) When placing the deck back in I want to seal to keep the water out. <br />I will use High Flex 3 epoxy over the ply wood, but it will not seal the "crack" between the plywood and sides of the boat. Silicone 11 is the best of the silicone caulks and can be painted over. I do like the idea of a rubber gasget of some sort.<br /><br />Fitz.

 

[gewf631]

Re: Deck Seal

Fitz,<br /> What do you mean by "inner liner"? In an aluminum boat, doesn't the deck just sit on supports of some kind? Anything else just flows back to the bilge.<br /> If this is the case, I'd hate to spend all that time in sealing the deck, only to have to deal with flexing of the deck (from people standing), and seeing all that sealer peel away.<br /> If the Silicone 11 is really Silicone II (as in Roman Numeral 2), I wouldn't give it more than a season. If you really want a gasket, it's getting to be winter, so most home improvement stores are chock full of different gaskets. You should be able to find something that works. And if you protect it by hiding it (with the carpet), it will last much longer (UV thing).<br /><br />Good Luck!

 

[Uncle Dave]

Re: Deck Seal

Ed. F<br />The deck is supported by 3 alum stringers and foam.<br />There was water trapped between the foam and hull and ribs. No way to drain. Only defense is to prevent its entry. The foam was not waterlogged, just trapped the water and the hull was deteriorating. Under all of the deck is foam except in the I/O motor well. <br />In 8 or 10 places it was eaten thru. One hole was the size of a silver dollar. Any how all are repaired (patched with ss screw and a patch). Alum boats and decks do flex therefore the need for a good and lasting deck to side seal. Silicone 11 (2) is a 20 year rubber caulking. Lots use it on boats. However it is not sun resistant.<br /><br />Fitz.

 

[Bondo]

Re: Deck Seal

Mr. Fitz,<br />I don't know what's been Eating your hull, <br />But, I Do Know it's Not Water.....<br /><br />I'd be looking at Eletrolisis....

 

[Uncle Dave]

Re: Deck Seal

Bondo,<br />When I removed the poured foam there was water trapped between the foam and the hull and ribs.<br />It had been there an extended time. By taste it was fresh althought the previous owner had used the boat in salt water. The boat has very few hours in the water , mostly trailer time. Stored out side with a leaky tarp. Water came in but could not leave. I have no doubt that water trapped between the foam and hull caused the problem. In the motor well (bilge) where there is no foam, there is no corrosion at all. Transom is also like new. No foam is against it either.<br />There was also some bad decay where it sat on the carpeted bunks. Completely thru in several places.<br /><br />I have completely dissasembled the boat and have found no wires to the hull or support members. It could have been wired improper prior to my acquiring but not very likely.<br /><br />In summary, leave a boat in the rain and pay the price of a shelter many times over.<br /><br />Fitz.