1988 Johnson Evinrude "CC" 9.9 thru 30 Service Manual, P/N 507660, Page 47Get this manual
Severe Service The fueloil ratio for recreational models approved for 100:1 operation must be increased to 50:1 (2 oil) when used in commercialrental, or extended severe service The additional oil is required to provide added protection against wear and corrosion of internal partsModels equipped with AccuMix will require 100:1 (1 oil) fuel oil mixture in the fuel tank in addition to the lubrication supplied by the AccuMix system FuelOil Mixing Instructions To be used if engine's AccuMixautomatic oiling system is not ote eSlre Gasoline is extremely flammable and highly explosive under certain conditionsAlways stop engine and do not smoke or allow open flames or spark near the boat when refueling or changing fuel tanksAlways mix in well ventilated area
rv Portable tankPour approximately gallonReplace filler cap (4 litres) gasoline into tank and add required lubricant securely Thoroughly mix by shaking tank Add balance of gasoline