Need Help on Transom Repairs

[coleman kayak1]

Hey Guys!

I recently picked up a 9.9 johnson to go on the back of my 12' fiberglass, for times where my 3hp lightwin just doesn't have enough umph (heavy wind/current/etc.). I've been working on getting the engine running good and believe I finally may have the upper hand on that one (still need to fix the tilt lever though).

However today when I was out doing some engine testing I noticed some not so great noises which were followed by some visible cracking around the transom. The boat is rated for 14hp so it *should* be able to handle it, but I think long before I owned the boat there were some "modifications" done.

The boat is a sears gamefisher but I am unsure of the year. The title says 1900 because it pre-dates the HIN, so that makes it pre 72. Needless to say, its been well used. The transom setup is unlike any other boat I've seen. The middle is fiberglass, then on the back there is a large metal plate that runs nearly down to the keel, and about 8" wide or so. Behind that there is a piece of wood. On the inside there is a smaller metal plate on the top, a metal "strap" on the bottom, and another piece of wood. (I'll attach some pictures at the end)

I'm thinking that this 9.9 between the weight and additional power is proving a little much. It also probably was trimmed down a little much (side note, need to free up the trim pin too). The cracking seems to be at the very top of the transom from the "torque" of the top of the engine pulling backward.

So, getting to my point, what do you guys think would be the best thing to do? Does anybody know of what this should have looked like from the factory? I have several thoughts but want somebody more experienced specifically with fiberglass boats to weigh in first. Thanks in advance!

Pics:

As an aside, the day was not all lost as I did get to putt around and test my new fishfinder, works great!

 

[coleman kayak1]

Well, I couldn't resist doing a little investigation. I started by pulling off all the metal and wood pieces. It became evident at this point the transom had obviously been repaired previously, and poorly I may add. There was a sheet of fiberglass cloth running along the transom, that pulled off with next to no effort. Not sure of why the lack of adhesion- but the fiberglass underneath was very smooth so that tells me they didn't sand/prep (note I am newbie with fiberglass, but know enough to sand with 80 grit to get good adhesion)

One the fiberglass cloth was gone I figured out why the center section of the top had a bigger diameter than the sides. Yes, that's conduit.

Once I lifted that off (just sitting there), I found what was left of the original transom:

Here's my tentative plan:

1. Get a piece of aluminum flat bar 3" wide or so, and bend to match the top curve, running from gunwale to gunwale. Cover with fiberglass cloth and resin extending at least a couple inches down the stern on the front and back.

2. Lay some fiberglass cloth over the transom area. I plan to extend at least 6" past each side and use one piece from the inside keel, up and over the top, to the outside keel. I plan to do at least 3 layers of cloth

3. Re-mount the metal supports with new SS hardware

4. Cut some new transom boards and install with new hardware as well.

Alternatively, I had thought about doing away with the metal setup all together, and using some 3/4 ply on both sides of the fiberglass.

Thoughts?

 

[CaptnKingfisher]

This reminds me of the time I tried to use a 9.9 on an 8' Jon boat! The transom immediately flexed towards the water and I zipped around as if my little jon boat were a jetski. The fear of losing my outboard to the lake was overcome by excitement at how fast I could finally go. I never learned my lesson.. I later had a 40 up tiller on a 14' fiberglass flat bottom skiff.

My suggestion to you is that you've outgrown the boat. You want more out of this old thing than it can give you. If the 'crack' sound in the transom didnt cause any apparent new damage, I'd sell it to someone who is only interested in using an electric motor with it. And this boat will be perfect for doing just that. These gamefishers are pretty thin and lightweight as I recall and cutting out the transom and trying overbuild a new one to handle the outboard, plus you sitting back with a gas tank and a battery.. that's a lot of weight in the back of this little boat. That's my two cents

 

[CaptnKingfisher]

Sounds like you're pretty set on doing this so I'd say remove the old transom, use it as a template. Cut two new ones out of 1/2" plywood and glue em together so you've got 1" thick ply. Then get ready to glass it in

 

[coleman kayak1]

Thanks for the input guys. The boat is rated for 14hp so not sure why with repairs it wouldn’t be perfectly capable of handling a 9.9. I ran a 20hp on my old 10ft aluminum once. That was definitely overpowered.

I didn’t pay anything for this boat so I’d still be money ahead if I can put a few bucks in and have it functional. At this point I’m just trying to figure the best way to repair. Heck, even if I sell it I need to get some kind of transom on it