Dave, those motors have been made from 1952 to 1968. 68 is the exception because it does not have a intergal tank and has a hood.
1952 to 1963
– 16:1 ratio was required.
1964 to 1968
– 50:1 ratio was suggested.
With that being stated, you will get many opinions.
Between 1952 to 1968 the motor is the same except decals, knobs and addition to add a fuel pump(1964 to 1967).
1952 to 68 motors are not jeweled. They have a friction based system on the con rods going to the pistons wrist pins and the crankshaft.
1964 Presented the TCW oils which was far superior to regular 30wt motor oil, so oil fuel ratio to 50:1.
Alot of the those little motors are found to have low compression from lack of oil.
Some prefer to stick with the original 16:1 ratio.
Alot will use 24:1 ratio
Using a Synthetic blend at 16:1 or 24:1 ratio will have little smoke and excellent lubrication.
Your choice my friend. This my opinion, but does not make me 100% correct.
Cheers Dave and thanks for your help and advice over years for Mercs.
Cajuncook1
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