To fix the leaks, the screw holes had to be localized by spotting the repaired caulking. (see above)
Drill out the hole to prepare to fill the hole in the deck with epoxy. (see right)
Finish off with new caulking.
When the teak deck was mounted, the shipyard drilled holes through the teak an into the GRP of the deck and put in screws to keep the teak deck in position. This was done during the process of gluing it down. These screws were later removed and filled up with caulking. Some of these holes started to leak into the interior of the boat.