Fiberglass not bonded to plywood

[jeffrey.bean]

I have a 1990 18’ Chawk, the aluminum fuel tank needed to be replaced. After removing the tank, I noticed that the original fiberglass de bonded from the plywood, wondering what my options are to repair?
I did find some rot where the side console is located, so I plan on cutting that out, and replacing with new plywood. As far as that, the rest of the plywood is solid.
Thanks

 

[88 Capri (2022 SOTY)]

The two reasons I have found for the delamination would be improper surface prep during construction or moisture intrusion into the wood (suspectthe latter). I'm not sure how you determined that the other wood is good ie: stringers, transom.
Did you take bore samples of the other wood?
Drill into the wood (not all the way through) and inspect the shavings (light colored = good, dark=rot) if good fill hole with marine sealant like 3M 5200.
To repair I would expect to remove all delaminated glass. In the stickies in this forum (top of page) there is lots of information in regards to glassing.

 

[jeffrey.bean]

Thanks for the info.
As far as the other wood, I was referring to the deck core material not being rotten/soft, except in the helm area.
The plywood did feel moist, so I guess that answers my question.
Looks like I’ll be installing a new deck.

The transom is on the “to do” list

 

[flashback]

Your at a place where your probably better off gutting the boat rather than trying to piece it back. Even if most of the decking is just wet but not rotted the stringers under the deck are. A total resto can be easier than repairs.