[htillman]

I have sealed these hatches with silicone with success. They must be clean and silicone applied to the deck ledge. Then install the hatch. I tape the hatch and deck area and then fill the gap with silicone and wipe/push down with my finger, keeping it clean as I go, dipping your finger in water after cleaning and working the silicone makes it easy. You cannot let the silicone skin over. Or you will have a mess. I have learned a good pointer on the website, lie 80 pound mono in the bottom silicone so removal of the hatch at a later date will be simpified.