Re: Correct fuel/oil ratio for mid 1950’s Johnson

[retiredoz]

The Johnson Service Manual tenth edition – which I believe somebody uploaded for online access – has a section on Lubrication and Fuel blending starting on P81. Interesting reading in that it is very specific about the mixing process. Apparently if you just put gas in the can and add oil, it sinks to the bottom, and gets consumed first (smokey ??) while the upper layer has relatively little oil in it which may have wretched consequences.
By and large, the claim is that 24:1 is appropriate for motors prior to ’64. If you use more, they claim, you may experience more spark plug fouling and maybe excessive carbon accumulation.