The People of America's Oil and Natural Gas Indusry

The 'Acute Effects' of Higher Ethanol on Outdoor Power Equipment

Mark Green

Mark Green
Posted October 31, 2013

The Outdoor Power Equipment Institute (OPEI), an international trade association representing more than 84 small engine, utility vehicle and outdoor power equipment manufacturers and suppliers worldwide, is closely watching public discussion of the Renewable Fuel Standard’s ethanol mandates and the push for wider use of E15 fuel. That’s because the small engines its members build and supply aren’t designed for higher ethanol blends. A look at E15 from OPEI and others in the small-engine sector:

Leading engine manufacturers … are warning users of all gasoline-powered lawn mowers and other outdoor power equipment to be vigilant when fueling their equipment. Gasoline blends containing more than 10-percent ethanol — such as E15 and E85 –should not be used. These blends, which are already available in several states, can cause permanent and irreversible damage that is not covered under warranty. – OPEI

“Our interest is to protect the consumer; we’re trying to prevent the harm from happening in the first place. … EPA has acknowledged there will be mis-fueling with E15; there will be engine and product failure.This is the reason the outdoor power equipment, boating, UTV, snowmobile, auto, and motorcycle industries, as well as the American Automobile Association (AAA) and the Coast Guard, oppose this higher ethanol fuel. Our interest is in protecting our customers.” – OPEI President and CEO Kris Kiser

Will this damage my lawnmower, boat, jet ski, snowmobile, or four-wheeler? It sure will if you don't pay attention. Generally, small engines are not designed to deal with the more corrosive E15 blend. And, as we mentioned in 2010, ethanol forms a brown goo when left in a fuel tank too long, which can clog fuel-system components. Two-stroke engines run hotter with an ethanol blend, which accelerates the potential damage. And ethanol can wreak havoc on fiberglass fuel tanks in older boats. Groups like the National Marine Manufacturers Association and Outdoor Power Equipment Institute have issued strong warnings to consumers to pay attention to their fuels or risk severe engine damage. Use a fuel stabilizer if the engine will sit for more than a few weeks without use; this will reduce the ethanol–water separation and potential gumming issues. Be careful to avoid using E15 in uncertified engines like these, at least until the subject is studied more thoroughly, and the engineering catches up to the fuel. – Popular Mechanics

"Ethanol has inherent properties that can cause corrosion of metal parts, to include carburetors and the degradation of plastic and rubber components. It can also reduce engine life and make them harder to start.” – Marv Klowak, OPEI member Briggs & Stratton

Are higher ethanol blends really that harmful to outdoor power equipment? Yes. You might be tempted to use a higher ethanol blended fuel since it may be less expensive. However, greater than 10 percent ethanol in outdoor power equipment can corrode metals and rubber and cause engines to break down more quickly. Most outdoor power equipment was not built, designed or warranted to run on fuel greater than E10, and using higher ethanol blends can damage or destroy it. In fact, using any fuel that contains more than 10 percent ethanol is illegal to use in outdoor power equipment. Also, the higher the ethanol blend, the lower the fuel economy. Ethanol contains 33 percent less energy per gallon than gasoline, so engines fueled with higher ethanol blended gas will attain fewer miles per gallon than those running on conventional gasoline (E10). This means you must fill your gas tank more frequently when using higher ethanol blended fuel. – OPEI

"The higher the ethanol content, the more acute the effects.” – OPEI

Manufacturers of outdoor power equipment and their engines say they will not honor the warranty of a product someone has been running with E15. The reason? Besides the above effects of ethanol, engines running even E10 gasoline run hotter. And with E15, the results can be dangerous, considering reports of "unintentional clutch engagement"—such as a powered-up chain saw that suddenly decides, because it's running so hot, that you've pressed the button to start the chain. Manufacturers see a train wreck coming because their customers will ultimately blame them for problems. – Consumer

“E15 is universally opposed by our entire industry because of the problems it causes. … Research has shown that using E15 can have harmful and costly consequences on small engines and outdoor power equipment. Most engines would have great difficulty in meeting both emissions and performance expectations with this type of alcohol range. … Most gas stations have tanks where the supplier puts the mixed gasoline into the storage tank and the pump pumps it up. Because alcohol separates from gasoline, consumers can get a higher mix of alcohol in their fuel. If you increase to 15%, the effect gets multiplied, so you might end up with double the alcohol you expected. That’s a problem.” – Brad Murphy of OPEI member Subaru Industrial Power Products


Mark Green joined API after a career in newspaper journalism, including 16 years as national editorial writer for The Oklahoman in the paper’s Washington bureau. Mark also was a reporter, copy editor and sports editor. He earned his journalism degree from the University of Oklahoma and master’s in journalism and public affairs from American University. He and his wife Pamela live in Occoquan, Va., where they enjoy their four grandchildren.