Water infiltating boat

Folks,

So the issue that I am having is that. I have sealed the boat with a decent quality polyurethane sealant, primed, painted and completed the bottom of boat. I am having water infiltrate into the boat through the seam skids on the bottom of the boat. See pictures attached. I sealed the boat rivets, seams and everything inside the boat however due to no access under the bench seats was not able to seal those seams, rivets.

My question. Is it possible to drill a hole at either end of the seam skids and pump in a waterproof expandable foam to seal these skids and seams?

If you mean under the 'chines' as depicted below, what you propose is really not viable. First off it could freeze and 'pop' off the hull in the Winter, IF you boat in cold climates. But worse, it will hold water, that could make it even worse!

Now there should be a drain hole or 2 in them that allow water in there to get out, likely at the stern end, reasoning that the stern of a hull should always be positioned as the lowest point, in the water or whilst on a trailer. I suppose one could put the boat upside-down like shown, but on a slight 'tilt', with the stern positioned so that the rear of that chine 'cap' was 1-2" higher than the front of it, AND also with one side higher than the other side.

Then pour in a slow cure epoxy mix from the rear hole and hope it weeps all the way down the chine/hull interface on one side of the chine edge (inside). And once satisfied (you might even see epoxy flowing out somewhere, as more evidence for 'where' leaking) that one side of the chine INSIDE is done, tip the boat so the epoxied side is now higher, to seal the other side of the INSIDE chine edge.

Now to tell the truth, I am in this same predicament with my present, old '89 vintage 14' hull (used in saltwater too), but I have a ~10' long center chine 'cap', that luckily stops just as the bow V begins to curl up; otherwise the repair job would be WORSE! As a saltwater boat, I won't even try what I offered up above. So I have removed that chine 'cap' and it is UGLY under there - full of corrosion and weep holes! So I am cleaning it all up and will seal it permanently with slow-cure epoxy, where it will be riveted back in place with solid rivets, less any place (like you say) where access is a ***** to do; where then there I will use strong, but closed-end pop rivets.

Oh, and I also intend to clean/sand/clean and then prime (epoxy-based 2-part zinc chromate etching primer) and anti-fouling paint (special, expen$ive tin-safe AF paint) the INSIDE of that center chine 'cap' before the install. Done once, done right ... hope this helps!

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