Transom Repair 16' Sea Nymph

Just picked up a 1979 16' V hull Sea Nymph on Saturday. I had been looking on craigslist for a while and decided on the V hull for the extra space I would have later on once I convince my wife that we need to mod it. [-o<

The motor, although it seems to be underpowered for this boat, runs fine. No leaks that I could see when I had it out on the water except a little from the drain plug that is starting to dry rot. The only big problems I saw were the trailer being too short for this particular boat and the transom was pretty bad. I have done my best to research this out beforehand and have a basic understanding of whats involved with replacing the transom now I think. I'm planning on using the current one as a template to cut and sandwich two pieces of A/C plywood together. Just wanted to run some things past everyone before I get started...

1. To sandwich the plywood together... will gorilla glue work? Does it also require any stainless screws or just the glue?
2. To seal the wood afterwards, what product will work best for this? I have done lots of woodworking projects but have only ever used tung oil. While it seals and hardens nicely, I'm not sure of its use for outdoor applications?


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keptrich, I was looking over your post and I noted a few things. Overall a nice pick-up. Looks like a nice safe stable boat. Boy, when SEANemph rivits a boat they rivit a boat. Your motor looks like a long shaft. See the last large flat plate just above the prop? It's my understanding that should be about even with the bottom/keel of the boat. A couple of ways to fix that. When you replace the transom, just build it up five inches or just add a Mini-Jacker (look on line) to bring the motor up about five inches. A short shaft motor is 15" and a long shaft is 20". Also look a the post "New Member and New Old Boat Project" by Boater for a real nice strong home made mod. As far as making your transom sandwich, we like to over-do things around here. Waterproof glue and stainless. Now for the nosey part. Like what ja' give for that little outfit (it's ok to lie). Good luck, welcome aboard and keep up the post.

Thanks for the quick reply. I thought the motor seemed a bit long and was going to ask about that but didnt want to slam the forum with ten million newbie questions at once!

It had never even crossed my mind to make the transom taller to account for the engine.. #-o P.S. I paid 1200 for it, hope I didn't overpay. Wanted something my buddy and I could fish from but also big enough to take the family out on the lake swimming.

Not a bad price at all. Look up what your motor would cost new and your going to feel reeeel good about yourself. Go to smalloutboards.com/shaft.htm and they can splain it better then I can. Your boat will never be a speedster but with a 9.9 you will be able to go to small limited horse power lakes. You can even make you trailer longer somewhere down the line. A little of everthing's been done around here. Just keep looking and asking.

It had a 30hp Chrysler on it originally I was told which was replaced with this 9.9 to run on all the lakes around us with HP restrictions. He bought the longshaft because he didn't feel the original motor's prop was low enough to get full thrust? Not saying he knew much more than I about the matter though.

A question about building up the transom though... Should I get something to reinforce the area being built up such as aluminum diamond plate? The tag on the boat says its rated up to 40hp, if it were built up would that change anything as far as the rating?

When I replaced my transom I used gorilla glue and screws. I all so added a 1x6 oak board so I could run a 25hp motor.
Tite bond III would be another good glue to use.

I wouldn't worry about it if you stick with the smaller motor. Later you can reinforce the transom with larger braces if need be. As long as you have room between the stern seat and the transom you can brace the transom for just about anything.

I got started today taking out the old transom. Boy am I glad I did! I'm very surprised the motor was staying on the boat.. :LOL2: After getting the old wood out, I saw many places where my thumb would push straight through the wood so it was more than time for it to be replaced.

Is it acceptable/safe to use the same hardware to mount the new plywood in or does it need to be replaced?


A lot of the nails holding the top trim on came out with just my fingers. :?

Now I can see why.... :roll:

The plywood was very rotten along the bottom and along the first notches on either side along the top.

Have to be careful how I hold/move the transom because it is close to breaking. Glad I'm replacing it now instead of putting it off.

If the hardware isn't too beat up, it should be ok to use. Once you tap the worst dents out and paint it over it will be right as rain. Just remember to NOT use pressure treated plywood. It has some kind of horror movie reaction with aluminum down the line. Use the searce option for other input about replacing your transom. Go to "Jon and V Boat Conversions" forum and look at "Material Links" for tons of replacement hardware and other cool stuff.

Going to pick up some plywood today while in town. It's going to be hard to work on my paper that is due this Friday when I know there is another project I'd rather be doing...

The boat will be there. Get the paper done. Keep the prize in your eye. Your goal is to get the Sheep Skin. That will give you your future full of tin boats to come.

Well I was finally able to start working on this again. It took a lot of fiddling with my cuts to get everything just how I wanted but I have the transom cut and glued up now. Once the glue sets up, I'll drill my holes and start sealing the whole thing. Hope to have everything done and put back together by midweek so I can get back out on the water again.