Last week a Brewer owner ask where to get A.B.I. Port gasket material.   The answer is Mc Master -Carr   in New Jersey.   Their phone # is 609-689-3000     The item # is 9700K15  Buna-N Square O-Ring Cord Stock   3/8" Fractional Size,   .375" Actual Size      It was  $ 1.55 /  foot   & it takes approx. 3 feet to do a port.  My boat has 16 of them.   Drive the roll pins out (there are two on each port  forming the hinge)   Once removed & the port is in your hand take a flat tipped #2 screw driver & remove the old gasket material.  Once cleaned up start mid way between the roll pins & force the new gasket material in the groove keeping the splice at the top.  When you are all the way around the port cut it at least a 1/2 inch long & then keep pushing the rubber materialout into the groove till the last part of the gasket material slips into the groove   It should be very tight & since the splice is on the top it will not leak.  It takes about 3 feet of material for each port.   If you have 16 as I do you need to buy 50 feet.  I would get some extra for future use.  Keep it in a cool place out of the sun  & it will be good many years later.

Hope this has been a help to you.  If you have further questions feel free to call me   Fred Chance  (717) 580-8191.