[JasonAych]

I have a 1988 Fisher 18' Aluminum boat. It has 4 strakes riveted to the bottom. I have a leak that I have been unable to resolve. Boat takes on about 5 gallons an hour. Since I don't leave my boat in the water and I am out about 3 - 4 hours at a time it is a huge deal. Takes A while to kick the bilge pump on, but when it does, the pump takes care of it fairly quickly. Still, I would like to fix it.

I investigated by filling the boat with water this weekend. I found that water comes out of the strakes at the lowest point it can find unsealed. The strakes are designed to fill with water there are gaps at the front and back and a drain hole at the bottom edge. So the problem is I can’t be sure what rivet is leaking. Maybe even a crack in there???

My plan of action is to buy cans of expanding (highly) sealant foam (probably polyurethane) I will drill holes down the bottom edge of the strakes insert the tube into the holes and inject the foam. I will be using a collar on the drill bit so I don’t drill through the hull. The thought is it will seal it inside out. I then plan to seal the outer edges with a seam sealer. I will use and epoxy for the drilled holes. The only concern I can think of is adding buoyancy. I have to believe this would be minimal. The only reason it would be a concerned at all is that it was originally designed to fill with water???

I am trying to avoid removing the decking. I believe the boat is filled with 2 part foam for the most part so I don’t anticipate being able to find the leak easily from the inside.

Any thoughts, concerns, do you think using the expanding foam in the strakes is a good or bad idea?

[Silvertip]

The strakes were not designed to fill with water. They were designed to allow any water that did get in there to get out. There is a process called "rivet bucking" which is the manual process for setting solid rivets. I suggest you study this process (plenty of info on the web) and with the help of a buddy, tighten all the strake rivets that you can get to from inside and outside the boat. If there is no inside access then the only way you could make a permanent fix is to drill out the existing rivets and replace them with seam sealer and solid pop rivets -- obviously a fair amount of work. Your proposal may work but I had one other thought would be to pour liquid truck bed liner into the holes to fill it. Seems to me it would make a better seal. Use a turkey baster to inject the bed liner.