Re: 40 year old aluminum jon boat need help sealing leaks
Hi am2018. 5150abf is right. You can rebuck any loose rivets you may find. However, if they're too far gone to be fixed I would drill them out and replace them with an aluminum rivet one size larger. You can get an inexpensive blind pop rivet gun form Harbor Freight for less than $20 and rivets can be ordered in bulk, online for cheap. While you can certainly use JB weld on small holes, I wouldn't use it on anything much larger than the size of a dime. For holes larger than that, JB makes an epoxy stick/putty which is better suited to filling in larger holes. While JB is great stuff, it doesn't flex well, so you shouldn't really use it on, or near the seams of the boat or any other areas which may have a large amount of flex while underway. I wold suggest you use a product called Gluv-it to seal the seams of your boat. It's a paintable epoxy with the consistency of honey. You first clean any corrosion or oxidation off of the seams of the boat with a wire wheel, then wipe clean with acetone and let dry. You then paint the Gluv-it on the INTERNAL seams of the boat only (no need to paint the whole floor). You then let it cure for 24-36 hours. The Gluv-it will will any and all nooks and crannies in the seams while still remaining flexible and 100% water resistant. Best of all a little goes a long way. One quart should be more than enough to do your whole boat. It does require some UV protection, so you'll need to paint over it, or install a floor in the boat.
As far as the transom is concerned, that's also pretty easy. There's really only one rule with aluminum boats: NEVER USE PRESSURE TREATED LUMBER. Marie grade is fine, but PT limber will cause an electrolytic reaction with the aluminum hull of the boat which will result in pitting and metal fatigue. Instead you'll want to use high quality, exterior grade, non-PT plywood, such as Aruco brand available at Lowes/HD. You'll then need to seal it with either wax-free polyester resin, then fiberglass matt, or you can simply coat it in 2 part epoxy and paint it. Most folks here seem to prefer the epoxy route for it's ease of use and lack of fumes, and its wide variety of uses, but it does cost a bit more. You can get it a West Marine, or any other boat supply store. If your budget doesn't allow for the epoxy right now, that's ok. You can get away with using spar varnish and/or high quality exterior grade paint like porch paint, or Rustoleum professional oil based enamel. They won't make your wood waterproof by ant means, like the fiberglass mat, or epoxy, but you should get several good seasons out of them. Also, be sure you only use Stainless Steel hardware dipped in 3M 5200 (a marine caulk/adhesive available at Lowes/HD). You can get virtually everything you need at a big box store, except the epoxy and/or fiberglass supplies. Hope that helps. Holler if you get stuck.
