1986 GW Tournament 19 Wet Transom

[LimitingFactor]

I purchased my first boat this July, an 86 GW Tournament 19. We've used it all summer (hundreds of miles and many hours) with only minor glitches. However, now that the season is coming to a close here in Maine, I removed the outboard for two reasons: First, the boat came with a 25" shaft motor on a 20" transom so I'm looking to either add a jack plate or potentially raise the transom which leads to reason #2. I could tell that some work had been done to the transom. After removing the bang plate/trim I could see that the gap shown had been filled with epoxy filler and was cracking. The top of the transom was also starting to crack. What I found was very wet transom with what looks like the original laminate schedule inside (I can see both plywood and fiberglass layers.) The gap in the transom thickness was filled with what I assume was epoxy filler which didn't bond to either the skin or the plywood so I started chipping it out. I removed all the drain tubes and various screws in the transom. About a pint of water came out. I am looking for feedback from others who have encountered this and what they did to repair short of a full transom replacement. Try to dry it out and then repair with Git Rot or CPES? Remove as much wood as I can from above and use Carbon Core? I'm thinking that the prior repair was performed with a wet core which is why it didn't hold up.

 

[DennisG01]

Those are pretty good pictures - quite telling. Unfortunately, the prognosis is not as nice as the pictures There's lots of separation of the ply and glass - also appears to be a good amount of swelling. I think you just found your "Winter project".

I believe you're in for a "skin the cat" transom rebuild, which really isn't all that hard - just time consuming. But, hey, it's nearly 4 decades old, after all. That said, good transom building is not something Grady has ever been known for.

Cut the transom skin off - stay about an inch or two away from the outer edges and the hull bottom. There's strength in those areas and it's easiest to just leave it and then dig out any remaining core. Saturate the new core (marine ply/Coosa/whatever) completely with epoxy before putting it back in ("paint" it with epoxy - don't forget the edges - until it doesn't soak in after about 15 minutes). Use a bunch of temporary through bolts to hold everything together. Get plastic bolts - epoxy doesn't stick well to them, but they're easier to break/drill out/remove if you need to. You can take an extra step and coat them in a good wax (don't wipe it off - just let it dry).

Thickened epoxy can be used at the edges so you don't have to worry about cutting the wood "exact".

An oscillating tool is nice to do the cut.

This will also give you a chance to replace the hoses for the scuppers.

 

[LimitingFactor]

I had an independent shop come by to quote a new transom on Tuesday. The other option is to dig out as much of the rotted wood as possible from the top, dry out whatever is left and pour CarbonBond transom compound.

 

[seasick]

I had an independent shop come by to quote a new transom on Tuesday. The other option is to dig out as much of the rotted wood as possible from the top, dry out whatever is left and pour CarbonBond transom compound.

The problem with pouring a resin into the void is twofold: It is very difficult to get all the rotten material out, adequately prep the insides of the inner and outer shell especially at the lowest section and where the transom meets the hull sides.
The second problem is pouring the compound and getting it everywhere that the coring was removed. Voids are a common problem. In theory the pouring sounds good but in the real world, I am not so sure.