I have removed 10 bronze ports on my boat in order to repaint the deck.
There are 2 different styles of port - opening and fixed - each set with
approx. 75 stainless steel round head mounting bolts with washers (on the
exterior). Under every one of the washers on one set of ports is a small
rough irregular crater about the size of a wooden match head. Under the
washers holding the other ports, the metal appears unblemished. Are the
stainless bolts a likely culprit for the pits and different bronze alloys
the explanation as to why the pits are on one set of ports and not the other?