Need help with DIY jon boat transom replacement.

[Jogar80]

My 8yr old boy and I went on our first guided duck hunt last yr and now we are HOOKED. We booked another this year but we both want to hunt more often. I cant afford a guided hunt every weekend and the only good public land hunts down here are only accessible with a boat. Being that I’m poor and all, I went and bought a used jon boat. ‘82 1648 Lowe. Boat looks good, engine starts easy, all good but it obviously needs some work. I’ve replaced previous plugs made of self tapper screws and gasket washers with sealed rivets. Aluminum brazed and sealed some cracks. Done a lot of work on it with my boy’s help. It’s going to get a paint job next but I really need to replace the plywood transom and need ideas and guidance on how I can most easily and inexpensively do it myself. The rear looks to be a welded aluminum panel added somewhere down the line. I see on youtube about gluing 2 3/4” plywoods together and resin sealing. I thought about cutting the lip off the bottom channel and then replacing with new aluminum. I just cant figure how to get the old wood out and the new wood back in there. Here are a few pics. Show me the way please. Thank y’all for any help

 

[FuzzyGrub]

Welcome to Tin Boats!

That is quite the transom replacement. I'm not seeing a way to remove and replace the wood without cutting some of that aluminum. Maybe, if the wood doesn't go to the bottom of the bottom channel, and it is enough to clear the top wrap around alum. It would also need to be loose, ie no sealant holding it to the back skin. Most likely, going to have to cut that wrap around lip off, and remove the wood in sections.

For new wood, would recommend two sheets of 3/4" external ply, with waterproof glue. Then coated with epoxy or other good sealant.

Please keep us up to date with your progress.

 

[airshot]

Yup....gotta cut off the top cap after you remove the motor of course. Whether the corner caps need cut off or not, I can't tell from your pics. Any thru bolts or rivets will need cut off or drilled out to the wood can be lifted out. Hopefully in one piece so you have a template. You could screw or glue a smaller piece of plywood on the inside of that transom wood to keep it in one piece while removing it, if it looks p me it might come out in pieces. Worse case is having to make a cardboard template if it crumbles away when removing. Looks like a great Father/ Son project !! Keep us posted !!

 

[DaleH]

Well from what I see, especially with that top cap that’s not only welded in place, but also goes down to the new piece put on the rear of the stern … I would BEND THE SNOT out of that inside piece on the bottom that is holding it in place, or at least holding it UP and from falling down.

Note there are at least 2 bolts under the motor holding the old wood in place too.

Remove any of those such through-bolts that you see, then BEND the snot out of that bottom rail, or even cut it off and pull the old wood down. Use as a pattern, and replace.

Even if you can’t use that old rail, just use new through-bolts to secure it in place, also see new yellow holes for locations, and you should be fine.

Take a look at this post below for DIY how to make and use permanent epoxy plugs. If you dry fit your pieces first, you should be able to make similar ones work for your through bolts!

https://www.tinboats.net/threads/new-transom-–-1976-starcraft-‘holiday-15’-model.47405/

 

[lckstckn2smknbrls]

You are going to have to cut the very nice-looking welds.

 

[airshot]

Pulling it down might be a bigger problem, seeing how the wood is wider at the top than at the bottom...

 

[Jogar80]

Pulling it down might be a bigger problem, seeing how the wood is wider at the top than at the bottom...

Well from what I see, especially with that top cap that’s not only welded in place, but also goes down to the new piece put on the rear of the stern … I would BEND THE SNOT out of that inside piece on the bottom that is holding it in place, or at least holding it UP and from falling down.

Note there are at least 2 bolts under the motor holding the old wood in place too.

Remove any of those such through-bolts that you see, then BEND the snot out of that bottom rail, or even cut it off and pull the old wood down. Use as a pattern, and replace.

Even if you can’t use that old rail, just use new through-bolts to secure it in place, also see new yellow holes for locations, and you should be fine.

Take a look at this post below for DIY how to make and use permanent epoxy plugs. If you dry fit your pieces first, you should be able to make similar ones work for your through bolts!

https://www.tinboats.net/threads/new-transom-–-1976-starcraft-‘holiday-15’-model.47405/

View attachment 123972

Dale, Yours were exactly my thoughts. The bolts under the motor actually go through to the motor mount on the other side. I THINK i can do this. Still scared though.

Airshot, on that note, i wonder if the new transom HAS to go all the way to the corners?

 

[airshot]

Dale, Yours were exactly my thoughts. Still scared though.

Airshot, on that note, i wonder if the new transom HAS to go all the way to the corners?

Depends on how much HP your gonna run..small motor to put arund, then no problem, but bigger motors pushing a load...stronger and longer is better!

 

[Jogar80]

Depends on how much HP your gonna run..small motor to put arund, then no problem, but bigger motors pushing a load...stronger and longer is better!

Running an old 30hp Tohatsu. Haven’t been out on the water with it yet so don’t know what kinda power it’s making. Just wanted to be sure it’s sealed up tight before taking it out with my boy.

 

[KMixson]

I would try to use two pieces of wood for the transom. Run a strip across the bottom and up a few inches. Then take a bigger piece and push it under the lip on the top rail and then push the bottom of that onto the top of the bottom piece. The tighter the fit between the two, the better. The bigger top piece will take more of load while under power.

 

[Jogar80]

I would try to use two pieces of wood for the transom. Run a strip across the bottom and up a few inches. Then take a bigger piece and push it under the lip on the top rail and then push the bottom of that onto the top of the bottom piece. The tighter the fit between the two, the better. The bigger top piece will take more of load while under power.

Any chance you could illustrate this for me? Not really getting it. A sketch or drawing on my pic perhaps? Thank you!

 

[KMixson]

Start at the bottom. Place a piece the width needed in the bottom recessed lip and about 4 inches high. Then measure the distance from inside the top lip to the top of the piece on the bottom. Cut a piece that fits there. Push the top of it into the recessed lip at the top and then push or press the bottom of it onto the top of the piece installed at the bottom. You need to have the top piece as wide and as tall as you can get it since that is the piece that will be bearing the brunt of the load.