Mixing gas and oil Four cycle engines have oil in the crankcase, and don't mix gas and oil. Two cycle engines have no oil in the base, and rely on oil mixed with the gas to lubricate the engine. If a two cycle engine has too much oil, it will foul the sparkplugs. If it doesn't have enough oil, it will be severely damaged by friction. Some engines require a 20:1 mix, others a 50:1 mix and others 100:1 mix.

A gallon is 128 liquid ounces

At a ratio of 20:1, how much oil should be used for one gallon? _________

At a ratio of 50:1, how much oil should be used for one gallon? _________

At a ratio of 100:1, how much oil should be used for one gallon? _________

How many quarts of oil is needed to mix 5 gallons of gasoline at 20:1? 50:1? 100:1?

How many quarts of oil is needed to mix a 15 gal. container at 20:1? 50:1? 100:1?

How many quarts of oil is needed to mix a whole drum (50 gallons) for a hunting trip at 20:1? 50:1? 100:1?

5 gallon

15 gallon

50 gallon

One quart is 32 liquid ounces. Convert the above ounces to quarts, as we usually buy oil in quart containers.

Make a chart with the above values and hang it on the shop wall for future reference.

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