Two-cycle engines are designed to run on a mixture of gasoline and oil. If you're unsure if you have a 2-cycle engine and need an oil mix, check to see if your lawn mower has a single fill port or one for oil and another for gas. Depending on the machine you have and its purpose (lawn mower, snow thrower or hand held equipment), you'll need a different 2-cycle engine oil mix ratio.
Mixing oil and fuel ensures that your machine stays cool during operation. It's important to find the right balance because the wrong 2-cycle oil mix can damage your engine, and running it without oil can destroy it. To confirm the correct ratio for your equipment, check your Operator's Manual .
IMPORTANT: When creating your 2-cycle oil mix, only use oil that is labeled for use in "Two-cycle" or "Two-stroke" engines. Also, never use 2-cycle oil mix in a 4-cycle engine. While it will run OK, you will damage the spark plug and your mower will not start well until it's replaced.
Mixing Ratio GAS:OIL
|UNITED STATES OIL per 1 U.S. GALLON Gasoline (128 oz.)||*INTERNATIONAL OIL per 1 IMPERIAL GALLON Gasoline (160 oz.)||*INTERNATIONAL OIL per 1 LITER Gasoline (metric)|
|32:1||4 oz.||5 oz.||31.25 mL|
|40:1||3.2 oz.||4 oz.||25 mL|
|50:1||2.6 oz.||3.2 oz.||20 mL|
*Our 2-cycle oil mix chart also shows the amount per Imperial Gallon and per Liter for our International customers located outside of the United States.
While more expensive, synthetic oil is also more slippery, which in turn causes less engine wear and can extend the life of your machine. Synthetic oil is perfectly fine to use in your 2-cycle oil mix, but it must be mixed in the exact ratio specified for the engine. Do not follow any instruction on the oil package that says otherwise.
To mix 2-cycle fuel, start by putting the correct amount of oil into an empty gas can. Use the 2-cycle oil mix chart above to see how much you need based on your machine's required ratio. Then slowly add the correct amount of gasoline. Do not try to mix the gas and oil directly in the gas tank of your lawn mower.
IMPORTANT: While you can use older fuel in a 4-cycle mower if you've used a fuel stabilizer, you should not use any fuel that is over 30 days old in your 2-cycle oil mix. (learn about issues related to old fuel). Therefore, do not mix more fuel than you are likely to use in a month.
After you've mixed your oil and added it to your lawn mower, run the machine for a few minutes in a well-ventilated area to ensure the mixture works its way through the engine before operating. When you create your 2-cycle oil mix, take time to examine your machine for other repairs or routine maintenance tasks. If you spot wear and tear on any of your lawn mower parts , order a replacement immediately. You can also order the lawn mower oil you need right from MTD Parts.