Re: 1948-51 Evinrude
What is your serial number? Serial numbers up to 13000 are 1948 models, 13001 and up are 1949 models, and if the serial number is suffixed by a "C" she is a 1950 or 1951.
Your Sportsman uses Champion J6C plugs gapped to .030, point gap of .020, 1/3 pint of oil to a gallon of gas.