Performance Fuels

All Articles

Lawn and Garden Equipment Needs the Proper Fuel, Too

by Grassroots Motorsports

Posted on 11/28/2024 at 9:00 AM




Racetracks may occasionally go quiet, but engines constantly buzz away. You can likely hear them every single day: Just listen for all of the small engines powering lawn equipment. 

Like our performance cars, these small engines can have special fuel requirements. A biggie that helps small engine performance: Fuel that is free from moisture. How does moisture get into the fuel system? Easy: The moisture that’s part of the air we breathe is attracted to the alcohol found in most fuels. As stated right there on the pump, most gasoline sold today contains up to 10% ethanol.

Where modern cars feature closed fuel systems that prevent the vapors from escaping into the atmosphere, most lawn equipment makes do with an open fuel system. A simple vented cap provides the necessary pressure equilibrium between the tank and the outside world.

And that vented cap also allows air–complete with some moisture – to enter the tank. The moisture then mixes with the fuel. The result can range from no operational issues at all to an engine that runs poorly or even won’t start.

Zachary J. Santner, senior specialist of quality at Sunoco, admits to salvaging more than one piece of discarded lawn equipment from the side of the road. The usual culprit that sends mowers and the like to the curb? A bum carburetor caused by fuel issues; he reports.

He offers an easy way to keep moisture out of your small engine’s fuel supply: Consider a gasoline that’s free from ethanol, especially for really small engines that can easily choke on moisture (like those found in string trimmers) and those that sit for a while (like rarely used rototillers, snowblowers or leaf chippers).

Most big-box home improvement stores sell ethanol-free fuel right there in the power equipment section. A 110-ounce can–not quite a full gallon–can retail for about $25.

Santner adds that Sunoco Race Fuels makes a fuel specifically engineered for storage: When properly kept, the brand’s ethanol-free Optima has a shelf life north of three years. This 95-octane fuel is also highly refined to be free of gunk–varnish, waxy residue and other trash that can stop a mower dead. A 5-gallon pail sells for about $95, making it more economical than the stuff sold in the lawn and garden center.