Transom repair question

[Ced]

Hi all,

I’m looking for a little help with the transom repair. I just bought an old 16 ft aluminum boat, with a new 25hp etec. The transom is rotten. It is 2 layers of 3/4 plywood, not sure yet what it looks like between them.

When i replace it, will i need to put one plywood on the outside and one on the inside as it is now? Or can i out 2 on the inside?

Thanks,

Ced

 

[lugoismad]

Don't use regular plywood.

And you don't want to use treated plywood because the copper in it reacts with the aluminum on the boat.

What I used on my previous 16' boat was birch plywood. You want to use the birch because it doesn't have voids in it like regular plywood, so it won't compress or break down as easily and won't hold moisture. Mount it up, drill all the holes for the bolts, and then soak both pieces in as many coats of spar urethane as you can. At least 3 coats, if not 5. Just keep letting it soak it up. Especially around the edges where its been cut. Then after the urethane has dried, paint it with some oil base paint. You want to prevent it from soaking up any water, so you need to plug all of the pores in it.

 

[Ced]

Thanks for the reply. My local hardware store said they only have “regular construction” plywood. I will have to check out another store.

 

[DaleH]

I'd put both pieces inside, see the Sea Nymph in my signature for a transom DIY 'how to'.

 

[Ced]

Thanks for your inout DaleH. I got some good information from your post. I am bringing the outboard to the local shop for a check up on Wednesday and will get to work on the transom afterwards. I’m excited and nervous to see what it looks like without the wood.

I just noticed a leak in the front of the hull...not sure how to fix it. I guess i should start another thread for that?

 

[Ced]

Anything look odd to you guys?
There was a 3/4 plywood on each side of the metal. They were not glued.

 

[Ced]

I'd put both pieces inside, see the Sea Nymph in my signature for a transom DIY 'how to'.

Dale H, had a look at your transom repair guide. Very useful. In my case when you say both pieces inside: Do you think the small transom piece (see my pictures), x2 would suffice? Or would you actually remove the knee (which is riveted) and put in a bigger piece?

 

[gorjes]

I'm planning to replace the wood in transom of my Feathercraft 12 Topper with starboard, will never rot or react w the metal

 

[DaleH]

I'd put both pieces inside, see the Sea Nymph in my signature for a transom DIY 'how to'.

Dale H, had a look at your transom repair guide. Very useful. In my case when you say both pieces inside: Do you think the small transom piece (see my pictures), x2 would suffice? Or would you actually remove the knee (which is riveted) and put in a bigger piece?

Did you see the picture of my 12’ skiff that I added new transom wood into? Two pieces, where the 1st piece against the tin went “down & around the knee”, by cutting a vertical notch for it.

See picture:

 

[Ced]

Do you have a link to the page? It is not in your signature.

Also another issue is a have a type of "L"bracket that is riveted just above the knee. Would you take it out? Cut an big notch in the transom for it? Any suggestions are welcome

 

[DaleH]

Do you have a link to the page? It is not in your signature ...

This picture is in the post a few replies above.

L-Bracket - Is that just a piece of angle aluminum? How is it attached? Can’t really tell by the picture.

Factory or added by a previous owner? Is it tied into the knee at all?

Most likely someone added it as an extra ‘stiffener’ across the transom to help prevent the center of the transom from pushing ‘in’ due to the thrust of the motor. But to me it looks barely adequate in size. However, you could easily re-fasten it to your new wood and/or tie it into the knee. Or use a larger width (legs) angle aluminum, then you can use the lip for storage of items too.

I have seen such stiffeners added to larger boats, one recently had a 6’ long, 4” wide 1/4” thick (2” legs) expen$ive ‘U’ channel bolted across where the hull’s OB transom bracket was affixed.

 

[Ced]

The L-bracket is riveted to the boat.
It seems sturdier than a typical piece of angle aluminum. I am unable to tell if it is factory or PO installed.
It is not tied to the knee.

 

[DaleH]

L-bracket looks beefy and integral. I’d just put 2 layers of ply as your new transom, sitting on that bracket, then up to match the cut-out ... and would be done with it.

 

[Ced]

I like that answer. Thanks DaleH.
I still don’t understand why there was a giant piece of plywood on the exterior.
My boat will likely stay in the water during the season and it didn’t seem right to have that much wood in contact with the water for prolonged periods