Have taken a M510 out of charter. One of the fresh water tanks (under the floor in the galley ) is leaking when filled more than half way and can expect it to "drain" when on a starboard tack. It appears there is a row of screws that hold the "lid" of fiberglass in place, down, shut. Any one had this problem, surveyor told me it was common. I am looking for a fix with out tearing our the floor etc. was thinking : remove screws and dry out with warm air over several days, rebed screws and new scres and use 3M 5200, I am trying not to tangle with fiberglass and WEST system repairs........ Any input is much appreciated.