Transom delaminatioin

mutski · Posted: Thu Sep 01, 2022 12:33 am Post subject: Transom delaminatioin

I just got my 2005 22-Cruiser back from the shop after discovering the forward edge of the transom was delaminating... the fiberglass was separating from the foam core. I originally thought I had done the damage, but when I looked at photos from when I bought it in Washington, the crack was already there.

The shop worker told me it's a common problem with production-grade outboard boats. The C-Dory is made from two fiberglass molds, one for the hull and one for the top-sides. The joint between the two pieces runs down the top of the transom, where in my boat, they are sandwiched around a piece of medium-density closed-cell foam. The gaps were filled with putty, the top of the transom faired, and the black plastic trim hid the joint. It's a weak spot, because the two pieces aren't fiberglassed together. He said it's likely the torque of the bouncing outboard motor pulled the layers apart when the trailered boat hit bumps in the road.

He said he found minimal water intrusion, and the transom was still structurally sound. He removed the plastic trim, filled the voids with a pint of fiberglass resin, put three layers of fiberglass over the top of the transom, then painted it black to mimic the plastic trim.

I feel l like a C-Brats weenie for hiring someone else to do the work. But we've entered the rainy season here, and I have neither a dry place to work nor the tools nor the experience. I just wanted it done so I could keep on playing. Hopefully, it's stronger than when it left the factory. I want to go halibut fishing on the next nice day!

Andesite · Posted: Thu Sep 01, 2022 3:12 am Post subject:

Looks like he did a great job. Was it Tim at TNT Marine in Homer by chance? He looked my C-Dory before I bought it.

pcg · Posted: Thu Sep 01, 2022 10:42 am Post subject:

Yes, I've learned this is a weak spot on C-Dorys with the black plastic cap. I've found similar on my '99 22 Cruiser and, barring the plywood core needing more than minimal repair, I plan to grind off the top (previous owner had applied epoxy over the joint), feather the sides, then lay a fiberglass cap over everything. I had intended to also replace the black plastic cap to give added protection, but the factory no longer uses the cap. They now seal the joint with fiberglass, as it should be. I suspect that many of the boats with the black plastic cap may show similar.

thataway · Posted: Thu Sep 01, 2022 12:20 pm Post subject:

mutski · Posted: Thu Sep 01, 2022 1:49 pm Post subject:

Jeff Sinn of Morris Marine in Homer did the repair. He did thicken the resin he poured into the voids. We talked about epoxy as a quick fix, but concluded a few layers of glass over the top of the transom would be more likely to last. Interesting that C-Dory has dropped the plastic trim. A layer of glass is certainly a better idea. I also asked him about the transom saver. His opinion was that the boat and trailer flex and move so much on the road that it's probably not much help.

thataway · Posted: Thu Sep 01, 2022 2:32 pm Post subject:

Alaskadory · Posted: Sat Sep 03, 2022 2:56 am Post subject:

How was the black trim taken off? Is it glued on?
I also have a 2005 and have been wondering what’s under that trim.. I did a similar repair to my Boston whaler transom that had started to separate.

thataway · Posted: Sat Sep 03, 2022 1:21 pm Post subject:

mutski · Posted: Sat Sep 03, 2022 3:06 pm Post subject:

T.R. Bauer · Posted: Sat Sep 03, 2022 3:42 pm Post subject:

The old boats like mine don't even have the plastic cap. I'm glad you were able to get it repaired during this season. Everyone is so stinking busy!