I used some WestMarine Six-10 thickened epoxy to seal some holes and then re-drilled them.
the Six-10 comes in a cartridge with a mixing tip.
www.westmarine.com
Greg
the Six-10 comes in a cartridge with a mixing tip.

West System Six10 Thickened Epoxy Adhesive – Waterproof Bond | West Marine
The West System Six10 Thickened Epoxy Adhesive offers a waterproof, gap-filling bond ideal for structural repairs and bonding in marine environments. Easy to use and cures quickly for reliable results. Shop now at West Marine.

Greg