Paint failure... Dealing with hydrolized resin above the waterline?

[Zach]

guys,

I'm doing a paint job on my boat, and I've got a stretch of toe rail has hydrolized over time since 1964.

She's a bit of an oddball low production boat, in that the hull and deck are glassed together as her shear line wouldn't come out of a mold. The toe rail bulwark were glassed and faired out of the mold free hand. The mold flanges were cut off, rounded over and laminated and faired together, then gelcoated and polished/buffed. An incredible amount of work, but also an incredible amount of secondary bonding and laminating work to go with it. The white remnants of the gelcoat above the cove stripe are the filler they used before she saw the blue gelcoat.

One of the guys in the yard knows the boat and said the previous owner fought with the same problem since 1991... So I figured that since the gelcoat was still present, it might have been the culprit. So I ground it off last fall, and worked it out of the cove stripe with a sanding block... built it back up with awlgrip high build and got things slick. The primer has blistered back off.

Attached are a few pictures. The worst of it is under the top corner of the cove stripe the brown blobs are the goo that started coming out Saturday when I sanded the primer back off the area.

Any solutions to this other than put a grinder in it and see if I find a mud puddle somewhere in an inner laminate layer?