I had Beckson portholes on the previous
boat. Found out one way to stop the
leaks was to clean the gaskets as grains of
salt and dirt would compromise the sealing. Easy fix for the
gasket leaks, but still had to re-bed the porthole frames as the 20 year caulking had given up and more than half the portholes was leaking around the frames.
Ended up
buying brand new ones at a discounted
price of $155 each from Sailorman in
Fort Lauderdale. MSRP was $250. The new ones had more (green) tint and a better locking mechanism.
Ended up through bolting all 8 new portholes for a tighter fit, but had to drill 10 holes in each cover plate and another 10 holes through the side of the house, a total of 160 holes.
Big job, but no more leaks..