Crowsbeak,
The SuperFastwin will not be in the same zip code of quiet as your ’55 Fleetwin Aquasonic. This motor will make a lot more noise. That said, the ’53-’54 SuperFastwins are right up there on my list of favorite motors. I think you will enjoy it very much once you get a chance to run it. They run so nicely. Plenty of power to push a 14 foot boat around 20mph yet troll down to a very slow speed. Really good power out of a fairly lightweight package for a classic 15hp motor. There was a certain ‘refinement’ that seemed to have taken place in 1955 with both Johnson and Evinrude where things got a bit smoother and quieter. There were lower pans and cowl gaskets added to help isolate noise and the rubber mounts were added to the towers that reduced the amount of vibration that you feel in the boat.

I did the opposite to address my desire to be able to run one tank from motor to motor. I use a 2-line pressure tank and keep all my pressure tank motors original. I run my single line motors from my pressure tank using an adapter I put together that allows the fuel pump to draw fuel from the fuel line and allows the tank to vent through the air line. I put an inline paper element fuel filter on the end of the air line to keep it from drawing dirt and whatnot into the tank. Motor side 2-line fitting on one end and a modern single line tank side fitting on the other end. Need to use a barb fitting to get the 3/16 line from the 2-line to 5/16 for the single line. I have been able to run any of my motors from 5hp up to 18hp on the lake at WOT using this setup. I personally like the pressure fuel system and have less trouble with it than I do the suction system with leaks and such. That is just a personal preference, but I thought I would offer the perspective of keeping things universal from the other side of the coin. Best of luck with your Super Fastwin and welcome to the forums.

-Ben

You’re very welcome. I’m glad to have had the viewing of my videos play a part in your getting this motor. I think you will thoroughly enjoy it. Keep us up on your progress!

-Ben