Ethanol-blended gasoline can be problematic, because its chemical properties can cause engines to run rough and even wear out prematurely. However, retailers report a steady increase in the sale of premixed fuel that doesn’t include ethanol.
Kris Kiser, who is the president and CEO of Outdoor Power Equipment Institute, which is a trade association, says most power equipment can run on ethanol-blended gasoline, which is known as E10. However, consumers have to worry about phase separation. This kicks in when ethanol absorbs water—either in liquid form or via humidity—and the fuel separates. This leaves water in the gasoline tank, which can kill the engine, Kiser says. Also, ethanol—even the remnants of ethanol-blended gasoline in an engine—is corrosive to a lawnmower’s carburetor and fuel lines, he says.
In the interest of keeping their products operational, Kiser says, manufacturers produce premixed fuel and promote them as an ethanol-free alternative, and he expects that trend to continue.
However, Greg Bohls, who is the general manager of Buckeye Power Sales, which sells lawnmowers and other outdoor power equipment, points out that buying only premixed fuel can become prohibitively expensive. The cans, which range in size from 1 quart to 5 gallons, can be double the cost of what you’d pay at a gasoline station for the same amount of E10. We found 1-quart cans of premixed fuel that range in price from $5.49 to $8 (or $22–$32 per gallon). That’s why Bohls says he still promotes premixed fuel as an end-of-season product to flush out ethanol mixes or residue that’s built up from the course of the mowing season rather than as an in-season substitute.
Kiser says lawnmower manufacturers are working on engine designs that handle ethanol-blended fuel better. However, Bohls says the fact that most power-equipment engines are single-cylinder models, as opposed to the multiple-cylinder engines that vehicles use, makes the equipment vulnerable to damage from ethanol.