Prop strut attachment fairing

[aphil138]

While I was replacing the cutlass bearing this weekend, I noticed that there was some cracking around the area where the strut is attached to the hull. Probably just stress cracks. I knocked around the area with a hammer handle and there was a hollow sound to it. SO.... like any good boat owner, I kept picking at it until a large chunk "fell out". It looks like it was solid resin... no cloth or any other additive. Does not appear that it was even "bonded" to the metal strut.
My question is this, what to use to fill it back in with.
Marine-Tex or WestSystem? Do I need to barrier coat that small section since it just covers up the metal strut?

[sailingdog]

I would use fiberglass and reinforce the "fairing" for the strut, as that will help support the strut far more than just epoxy would. You shouldn't need to barrier coat it, since the epoxy is much more osmosis resistant than the polyester or vinylester resin.

Fair it out with a bit of thickened epoxy, and put a couple layers of glass over it, and then coat with some more thickened epoxy to finish shaping the area. Let it cure, sand lightly, and then prime and bottom paint.

I'd use West System Epoxy with their High-density filler. Not the collodial sillica filler, since that is going to be much harder to sand than the high-density filler IIRC.