4-cycle Tecumseh Snow King engines or engines used during the winter should use HD 5w-30 or 10w-30 For Service SF or SG. Do not use 10w-40 or 0w-30 oils.
With today's fuels having a very short life becuase of all the stuff they have to put in it to make it burn cleaner, Octane of 89 to 93 should be used instead of 87. Regular gasoline tends to foul more spark plugs than the higher octane fuels do.
Mix high grade gasoline with oil in your 2-cycle engines also. Get your 2-cycle fuel/oil ratios here.