The ratio of gasoline to engine oil for a Homelite gas trimmer is 50 to 1. The ratio is equal to 2.6 fluid ounces of oil for every gallon of gasoline. The mixture is made by combining unleaded automobile gasoline and two-cycle engine oil.
Only oil that is specifically designed for two-cycle engines should be used since other types, such as automotive and two-cycle outboard motor oil, contain additives that can ruin the gas trimmer's engine. The fuel should be used no more than 30 days after it has been mixed. Homelite also manufactures bottles of pre-mixed 50-to-1 ratio fuel that are specifically designed for its brand of grass trimmers.