Recently bought a 1990 Thundercraft 1560 bowrider. Have found too many needed repairs to list here, but the last one has me worried. After reading a post here that suggested sealing old screw holes in the stern by reinserting the screws coated with 3M 5200, I decided to do that. I removed three screws that were holding an old plastic transducer bracket on the bottom of the starboard side of the stern. When the third came out, it was followed by a steady stream of water, about the strength of a good beer whiz. I was suprised but figured it would only last a few seconds. More than an hour and a half later, gallons of water had come out of the hull. The drain plug was open and the bilge dry the whole time ... This water was all inside the hull and not going through the bilge or drain plug. My questions: How did it get there? Could it all have gone through this loose screw hole? If so, how come it never dripped? And if I reinsert this screw with 5200, how will I know if water is building up in there again? How do I keep it out if I don't know how it got in? Also, is there a similar compartment on the port side that could be holding water too? Do I have to bore a hole to find out? I've yet to put this boat in the water, been working on it instead, but the previous owner (a buddy) never realized his hull was full of water. Has anyone else experienced a similar situation? I am new to power boating and thought all water in the hull was supposed to go out through the drain hole or be pumped out by the bilge pump.
