Gas-to-Oil Ratio for a Homelite Weed Trimmer

Homelite brand string trimmers are powered by small two-cycle engines that require lubricating oil to be premixed with the gasoline. Unlike four-cycle engines powering other yard equipment, these lightweight two-cycle engines have no oil pump, oil reservoir or oil conduits. The gasoline-oil blend lubricates the engine's internal parts while powering the trimmer, ensuring that the engine doesn't overheat or seize from lack of lubrication.

Mowing Lawn With A Weed Trimmer
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Only mix enough trimmer fuel to use up within 30 days.

Gas-Oil Ratio

Homelite gas-powered trimmer models such as the Trimlite, Trim 'n Edge and Easy Reach 25cc string trimmers use a 50:1 ratio of fuel to oil. Make this mixture by pouring 2.6 fluid ounces of two-cycle engine oil into a 1 gallon gas can, then add a gallon of gas. Shake well to thoroughly mix the oil and fuel. Most 1 gallon cans hold slightly more than 1 gallon, so there will be room for the oil.

Two-Cycle Oil

The Trimlite and other Homelite trimmer models require an oil made specifically for two-cycle air-cooled engines. This type of oil is formulated differently from the oils used in four-cycle auto engines or the oils for two-cycle, water-cooled outboard motors. Using the wrong oil in your string trimmer can foul the engine and its fuel system over time.

Regular-Grade Gasoline

Homelite recommends regular-grade unleaded gasoline intended for automobile use. Gasoline should have an octane rating of 87 or above. Trimmers can use regular-grade automotive gasoline that contains up to 10 percent alcohol, an additive that prevents knocking in automobile engines. Motor fuels containing more than 10 percent alcohol, such as E85, can damage the trimmer's engine and should not be used.

Filling Tank

Be sure the trimmer is off and the engine is cool before filling the fuel tank. Place the trimmer on a solid surface. Wipe dirt and dust from around the fuel tank's cap. Shake the fuel can well to ensure the gas and oil are mixed. Loosen the fuel tank's filler cap slowly and set it aside on a clean surface. Carefully pour fuel from the can into the tank, avoiding spillage. Replace the trimmer's fuel cap and hand-tighten. Wipe up any spilled fuel.

Safety Measures

Mix your two-cycle fuel in a well-ventilated outdoor area away from structures. Keep children and pets away. Never smoke while mixing or pouring trimmer fuel. Store the fuel container out of direct sunlight and well away from sources of heat, sparks and flames. Never store trimmer fuel in your house. Store trimmer fuel in a container approved for gasoline. Never use makeshift containers.