leaking aluminum hull

[lbdavis]

I didn't know where to put this thread and I might get rotten fruit thrown at me for this:

There is an 18' aluminum run-about at my family's camp that has a JBweld patch on the bottom of the hull where it meets the transom. The patch has failed. I'm curious if anyone has a good solution to this. I've thought of using 5200 but I'm not sure how it will bond to aluminum and JBweld. Cabella's makes a patch for aluminum boats as well, but I have no idea what that stuff's like.

Any wisdom here on this subject? I bet there is...

Sorry mods if this stinkpot question is inappropriate!

[joeybkcmo]

no one has answered or thrown rotten frut yet. let me have a go at it. never had to work with patching an aluminum boat, but know that they make the patch kits, if you have any doubts would talk it over with the guys at Cabella's, and most of all follow the directions, no short cuts.

[sailingdog]

Can you post photos of the damaged area?

[Jeff_H]

I had an aluminum jonboat which came with a boat that I owned in the early 1980's and that I used as a dinghy for a while when I kept that boat on a mooring (the jonboat carried four people which was handy, and used the same outboard as the sailboat allowing me to safely store the outboard ashore, albeit at the price of many a nervous moments transfering it from the sailboat to the Jonboat and back again, but that's another story.)

The Jon boat leaked like a sieve when I got it. I ended up cleaning the aluminum by carefully sanding with wet and dry sandpaper, then used an alum. etching material that I bought in a hardware store, and then glassed the leaking area with a patch with epoxy and fiberglass. There was one area where the aluminum was sanded thin. There I made an aluminum patch that pop riveted in place with Vulkem caulk in between the hull and the patch if I remember correctly. I also glassed over that area from the inside. It worked okay. Occasionally a new leak would show up or one of the places would leak again. Never very dramatic.

Jeff

[lbdavis]

Sorry SD, no pics. I can't get at the boat until next weekend.

I can tell you that the existing patch is faired out JBweld that is in a roughly 1'X1'X1' triangle spanning around the whole stern of the hull where it meets the transom.

The damage was from a pretty solid grounding on one of those random chunks of granite that have made Maine's inland lakes so popular for recreational boating.

I wondered if FRP would work. Thanks, Jeff, I will put that firmly on the "possible solution" list.

This boat is not meant to be pretty and not trying to set any speed records. We use it to puts around the lake, do the occasional water-ski, and beach it on gravel-ly beaches.

WIth that in mind, I was wondering if simply covering the entire patch with a half a tube of 5200 would work. I'm sure it would seal it, but I wonder if it would last. I would have to assume there is some flex in the hull back there...

Thoughts? Or rotten fruit?

[sailingdog]

I was thinking that putting a patch with a layer of sealant between the patch and the hull and through-bolting it might work. You'd probably want to use a thicker strip around the edge of the patch to give it some strength.

[bubb2]

as a kid I had a aluminum river boat it got some holes in it, Aluminum epoxy putty sticks and sheet aluminum and pop rivets. never sunk but never stopped leaking. lol