Kyle2
Member
I am fitting a new engine to my 1974 Snapdragon. The water inlet and exhaust outlet require larger holes than the old engine, so I have to fill the holes left behind. There is a 30mm hole in the transom at the water line, and three small holes (about 8mm) around the main water inlet hole. I have used polyester resin and glass fibre mat before for fixing things to the inside of the hull, but I think I need to be more careful now to fill holes where water might come in if there is anything wrong with my repairs! This is my plan - does it seem a sound one? I'll chamfer all the holes on the outside. The large hole I will then abrade the GRP for 4" around on the inside and add layers of mat and resin to a thickness of about a quarter of an inch. When that has set, then I'll add resin and glass strands chopped small to fill up the hole on the outside. Finally, when all is set, finish off the outside with gelcoat filler. The small holes I'll block with cling film on the outside and fill with resin from the inside. When set, smooth off with gelcoat filler. Comments on materials and/or method gratefully received.