Re: PSC37 Forward Water Tank
The water tanks on our '37 are fiberglass and are actually part of the interior liner structure. Ours have plywood lids (that are coated with fiberglass on the underside. Though our lids have not leaked (yet) we did develop a leak on one tank caused by a cracked plastic vent fitting. The fix entailed cutting holes in the plywood tank covers to allow access to the tank interior to install new vent fittings. The holes were sized (about 4.5" dia.) to be covered with plastic screw in covers available at most marine stores. I think we used the Beckson parts with o-ring seals. We sealed the edges of the cover cutouts with epoxy prior to installing the covers. That was about 8 years ago, and no problems yet, and the covers allow me to periodically scrub out the tanks. So, the point of the story is to check out your tank fittings before tearing off the tank cover.
Crealock 37 #151