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Gas-to-Oil Ratio on a Lawn-Boy

Two-cycle gas engines that power Lawn-Boy walk-behind mowers are lightweight and strong, but you have to mix oil with gas. The Toro Company of Bloomington, Minnesota, the producer of Lawn-Boy mowers, recommends 2-cycle motor oil created by Lawn-Boy, Toro or among numerous 2-cycle motor oils that satisfies the TC-W3 standard of the National Marine Manufacturer’s Association. The gas-to-oil ratio varies by the year manufactured.

Gasoline to Utilize

Lawn-Boy recommends using petrol that’s 87 octane or near it. Employing higher-octane gas doesn’t add anything useful and some brands contain additives that are harmful to small engines. Gasoline with up to 10 percent ethanol alcohol is okay. Only buy gas you will use within a single month or even add a fuel stabilizer that will keep gas fresh from four to six months. You can buy fuel stabilizers in many dealers of small engines.

Models using a 32-to-1 Ratio

Add one 4-ounce can of recommended oil to 1 gallon of petrol, a 32-to-1 gas to oil ratio, for all these 2-cylinder Lawn-Boy models: A-10; A-11; A-12; C-10 through C-17; C-20 via C-22; C-40 via C-42; C-50 and C-51; C-60 and C-61; C-70 via C-78; C-80 and C-81.

Ratio by Date of Creation

For some Lawn-Boy models, the recommended ratio of gas to oil depends on the date it was manufactured. Add one can of lubricant a 1 gallon of petrol for all these models manufactured in 1971 or earlier: C-18 during C-19B; C-43 and C-44; D-400 through D-4008; D-405E through D-408E; D-430 and D-431; D-440 via D-448; D-445E via D-448E; D-450 via D-452; D-460 via D-462; D-475; D-480 and D-600. If those models were produced in 1972 or later, add one can a 2 gallons of gas.

Ratio of Old D-Series

For D-series models manufactured between 1954 and 1977, add one can of lubricant for 2 gallons of gas. These models include D-409, D-433, D-449, D-463, D-476, D-481, D-601, D-601E, D-640, D-641 and D-642AE.

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