We have a Johnson Motor,,,the only numbers we can find on it is RD-15, 1031116. We were wondering if anyone could tell us the year and size of this motor?
1953 1/2 - 1954 25 hp Johnson.Original mix ratio for fuel was 24:1 .Some mix those engines at 32:1 since the evolution of better TCW oils as opposed what was used in the old days.In any case us TCW3 oil and fresh 87 octane gas.Use Champion J4C sparkplugs gapped at .030".
