Jon boat leaks at transom

[oldgreenboat]

I recently acquired a 14' RyanCraft aluminum jon boat. The rear end of the boat has been damaged by dragging the boat over rocks. The wood transom is rotted and needs to be replaced.

The seam where the bottom of the boat meets the transom leaks. There may be a crack in the tube that makes up the drain hole. The previous owner used Alumi-weld or similar product to make repairs. That coating on the bottom of the boat has some separation. I can put a fingernail between it and the bottom of the boat.

I filled the boat with water and noticed a slight dripping about 1" forward of the drain hole. When I applied slight pressure on a new drain plug from the outside, water seeped from the hole. When I got the boat onto the lake for a test, the boat leaked and I returned only after 10 minutes.

How can I fix these leaks? Will more Alumi-weld work? Should I take the boat to an experienced aluminum repair shop?

I've read about replacing the transom. I'd have to remove the rivets holding the brace to the bottom of the boat, then use bolts.

I have attached a photo of the rear portion of the boat. Thanks for any comments or suggestions.

 

[robert graham]

Re: Jon boat leaks at transom

of course new rivets and a good weld repair would be best but if you just want a cheap and easy fix, them wire brush all the loose rivets, cracks and leaks and apply 3M yellow weatherstrip cement inside and outside and you should be good to go for at least a year, then you can go back and touch up any areas that are worn or leaking. I have a 1983 riveted aluminum canoe and this has worked great. I tried the aluma-weld stuff and the 3M cement is better, stays flexible longer. Good Luck!

 

[kciv]

Re: Jon boat leaks at transom

On the part that is scrapped down I would use J-B Weld to build back up. You can also use J-B Weld to glue on small thin pieces of aluminum. I used 2" dia tar paper disk. Make sure you use aluminum and not tin. Mine were on the flat but your could bend them and put them on the edge.

 

[oldgreenboat]

Re: Jon boat leaks at transom

I attached the photo that didn't appear on the first post. Can you explain your comment about the tar paper disc? Thanks.

 

[kciv]

Re: Jon boat leaks at transom

Disk you can buy at the lumber yard for $2.50 a pound. You get a lot in a 1/4 lb. These aluminum disk are used to hold tar paper down. You put the tar paper down place a disk on it and drive a roofing nail are staple through both. The picture shows a flat disk that you can use to patch a flat surface and one that I bent 90 degrees to use on a edge. Cut them and bend them to fit. Glue them on with epoxy and cover the edge with a epoxy bead. The previous picture showed how I patches a transom. I put a disk on both sides of the hole (inside and outside).

 

[oldgreenboat]

Re: Jon boat leaks at transom

Thank you for the information. I think that I'll try the JB Weld to build up the thin spots, then use the discs on some of the other areas.

On the seam where the stern meets the bottom of the boat, will JB Weld hold due to any flexing? Or should I use something like Cabela's Aluminum Boat Patch or Gluvit? (I currently just use an electric trolling motor, but may have access to a 3 HP. Also, I'd like to do a job that will last another five years or so.)

Again, thanks for your help!

 

[Bob_VT]

Re: Jon boat leaks at transom

Gluvit is the 2d best...... welding in new aluminum is the best.

If your hull has rivets you should use gluvit on the rivets and seams. I do not think those aluminum discs are thick enough (they are paper thin) but going to a scrap metal dealer may yield some aluminum sheet metal. Some people have scrapped whole aluminum boats and they will provide good size pieces.

MO is full of aluminum boat builders and maybe scrap is available there.