and Yes, George is right, the electric fuel pumps meet marine standards, and I haven't seen a marine fuel for a 455 in Years, if ever, I think the Olds pumps are a different design than the other GM pumps, if the diaphram starts leaking inside one of those, the fuel will excape into the crankcase, like the Fords, and not spray out into the bilge, and they don't have the little bleed hole in the top of them like the older Chevy automotive pumps.
You need a pump that will push about 7 to 9 psi for that 455, 4psi will runn it just fine, but thats about the minumum
I understand that the 455 olds marine application fuel pump is no longer available. Most go the electric route with a pressure regulator. You might try to find a rebuilder for the pump, or get a car pump, and use those parts to rebuild your old pump.
Good luck on this project, and post some photos. We like pics!
I'm new to the site, but have recently purchased a 1973 Glastron Carlson Jet Boat with 455 Olds. I'm having the hardest time finding a fuel pump for it. Instead of trying to go back to original I'm being told I should just install an electric fuel pump and be done with it. Do they not make a marine mechanical fuel pump for the 455 Olds motor?