MVD,
Post a picture or two. I'm sure Rick or Jeremy will have some excellent suggestions.
I personally like the temporary idea of stuffing it with Marinetex (or Formula 27). If the crack is 1/4" wide

is there any deformation/elongation of the trunk opening at the hull? If the board only had a minor ding, I'd guess the crack existed before this latest thump.
IIRC, the doesn't hull roll in to the trunk and extend upwards an inch or so? Then the trunk itself is wrapped, if you will, around the deck and hull "lips". I've only encountered leaks at this joint/seam between the hull lip and the trunk.
I'd assume this crack to be at the very bottom, or actually in the hull lip? If so, I'd dope it up with Marinetex (temporary mind you) and install a new Hobie #40309001 neoprene kit.
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