It is easier to convert a 18hp from the 1950's because they have bypass covers, but the 5.5hp motors do not. So, there has to be a different approach.
Certainly you could find and repair a pressure tank and your motor would easily run well or I could point you some articles and video of converting your 5.5hp Evinrude.
I have 1954 5.5hp Johnson, 1955 Evinrude 7.5hp and 1955 Evinrude 15hp that run great off a dual hose pressure tank.
click on video below to play.
Hey johnnyt, as a hobby I like to repair and restore old motors. If you are still interested in getting your old motor going, I would be happy to give you advice and tell you how to repair that old girl.
If that motor has good compression then it is worth fixing. The 1950's and 1960's 5.5hp and 6hp Evinrude and Johnson motors are some of the best and most reliable motors made. I have a lot of literature if you need.
You can PM me back if you are interested.
David
