Trips to the pump are a lot different now than they were 20 years ago. Up until about the turn of the millennium, we had choices of regular, super or premium. Different octane levels, but all 100 percent gasoline. With the integration of ethanol into our fuels, we now have to be more careful about which button we push, especially when filling a fuel tank of a small engine on our lawnmower, snowblower and log splitter. Ethanol blends, even in small concentrations, have the potential to cause some bothersome problems for our customers.
Ethanol is corrosive
Ethanol absorbs moisture like a sponge. Even blends as weak as E10 have the ability to retain up to 50 times more water than pure gasoline and carry it through your fuel system. After prolonged use, that water corrodes parts like an engine's fuel line and carburetor that can't withstand a little extra H2O until, eventually, enough rust forms in those narrow passageways to restrict fuel supply to the cylinder.
Ethanol deteriorates plastic
Consumer Reports, ethanol affects more than just metal. Rubber and plastic are also highly susceptible to ethanol corrosion, but in a different way. While composite parts like fuel pumps and hoses can't form rust, they can be dried out and hardened by ethanol, causing them to crack and fail.
Ethanol is a solvent
Sounds great for cleaning, but not so great for the fine art of internal combustion. When used in older engines that have varnish buildup, ethanol can dissolve those varnish deposits and the deposits can clog fuel lines and carburetors.
Ethanol decays quickly
Ethanol contains a higher oxygen content than pure gasoline, meaning ethanol-blended fuels can deteriorate more quickly. When left untreated for long periods of time, oxidized fuel can leave gummy deposits in your fuel system and clog it.
While ethanol use in small engines can be damaging, consumers have the choice to purchase a variety of fuel blends, including 100 percent gasoline. But with those choices, awareness of the labels on the pump as well as the actual type of fuel pump used to supply that fuel is a requirement. Single-source pumps, or pumps with several fuel blend options but only one hose, can hold up to one gallon of fuel in the hose alone, meaning you could be getting whatever the last person pumped, regardless of your selection. A gallon may not seem like much, but if the last purchase at that pump was E15 or E85 and you're filling a small tank, you could be purchasing a risky ethanol concentration. Best practice is to always fill at pumps with dedicated hoses for each fuel type.
According to the U.S. government, gasoline with an ethanol content of 10 percent or less is technically acceptable for use in small engines. Key word there is, "technically," And while The Outdoor Power Equipment Institute (OPEI) agrees, we think it's better to be safe than sorry and to use 100 percent gasoline in all gasoline-powered Ariens® and Gravely® equipment, every time. The majority of customer calls into our support line result from fuel-related issues, and we don't want yours to be next.