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Potent E20 gas could increase fuel woes

Some say marine engines can’t handle fuel with 20 percent ethanol, and it could mean more problems for boaters

Some say marine engines can’t handle fuel with 20 percent ethanol, and it could mean more problems for boaters

Just as boaters appeared to be recovering from problems caused by ethanol-blended gasoline, a more potent fuel with twice the amount of ethanol — E20 — could soon be unleashed on marine engines and fuel systems.

Read the other story in this package: Ethanol makes its way to the courtroom

E10, a mixture of 10 percent ethanol and 90 percent gasoline, has led to the disintegration of fiberglass fuel tanks, the gumming up of fuel lines, and piston and valve failure. Ethanol attracts water, and because boats are kept in damp environments, accumulation of moisture is inevitable in a boat’s fuel tank, particularly boats that aren’t used very often. When the ethanol-and-water mixture falls out of the fuel in what’s known as phase separation, a layer of sludge and/or water forms at the bottom of the fuel tank, which can cause engine problems.

Minnesota has led the charge for E20, and the state will mandate the switch to a 20 percent ethanol blend by 2013. “They’ve scared the crap out of us,” says John McKnight, director of environmental and safety compliance for the National Marine Manufacturers Association. “We’re drawing the line at E10. Anything more means big trouble. We’re fearful of these incremental increases.”

Proponents of the change to E20 welcomed a recent study by Minnesota State University Mankato and the University of Minnesota that states gasoline with 20 percent ethanol works just fine in most road vehicles. “The drivability study showed that E20 provided similar power and performance to 10 percent ethanol-blended fuel throughout the entire calendar year, which included a broad range of ambient weather conditions,” the study concludes.

Republican Sen. John Thune of South Dakota says the study — released in March — will help convince the federal government to approve higher blends of ethanol such as E20 for all vehicles, not just those that can run on fuel with high levels of ethanol (up to 85 percent). These are called flex fuels. Cars such as the Chevrolet Impala can run on flex fuel.

Thune says the benefits to motorists are obvious. “By increasing the blend of ethanol, consumers get more choices at the pump, we reduce dependence on foreign oil, and we lay the groundwork to build our domestic ethanol industry for years to come,” he says.

But those operating marine engines — and other gasoline-powered equipment such as string trimmers, lawn mowers and generators — won’t be happy, according to the Alliance for a Safe Alternative Fuels Environment, or AllSAFE. “If we bring these fuels to market and consumers don’t understand them or they find it’s detrimental, there’s going to be a backlash against the fuel,” says AllSAFE spokesperson Kris Kiser.

Ethanol is an oxygenate, helping gas burn more completely and thus reducing emissions. However, higher levels of oxygen in the fuel will take its toll on marine engines, which aren’t equipped to adapt to increased oxygen, says McKnight. The engines will run leaner — and hotter, leading to warped heads and damaged valves, says McKnight.

The NMMA cites a study by Australian company Orbital Engines that contradicts the university study. The 2002 study reports that E20 can cause filter blockages, swelling of plastic materials that make up the fuel system, and corrosion of metal components. “Vehicle operability may deteriorate with 20 percent ethanol blends,” the study says. “Those vehicles fitted with lean calibrated carburetors are likely to display the most significant deterioration across the drivability spectrum due to enleanment. For those vehicles fitted with closed-loop fuel injection systems, enleanment is likely to deteriorate the cold-start performance and warm-up.”

The Orbital study lacks actual testing of marine engines running on E20; its conclusions are based on physics, not test data.

The Department of Energy asked the marine industry to submit by the end of April its recommendations for testing the effects of E20 on marine engines. McKnight has outlined four areas of concern, which include the durability of fuel-system components, the compatibility of E20 with fuel-system materials, E20's effect on emissions, and overall engine durability.

“This is good news because more testing is needed to determine what exactly will happen if E20 is used in marine engines,” says McKnight. “The federal government recognizes we have to go through the proper testing.”

For boaters, E10 has become less of a problem because they — or their mechanics —now know how to deal with it, according to Rich Kolb, Volvo Penta’s engineering manager for emissions, regulations, parts and accessories.

Soundings technical consultant, Erik Klockars, agrees. As a marine mechanic, Klockars has endured the E10 learning curve over the last three years. Maintenance now includes changing all water-separating fuel filters at least once a season (twice in warm climates), using fuel filters that remove the smallest particles possible (lowest micron rating) without restricting fuel flow and being aware of ethanol-blended fuel’s shorter shelf life.

“You should fuel up when you leave the dock, not when you get back, so if you don’t use your boat for several weeks a smaller amount of [E10] fuel will be affected,” he says.

There are ways to deal with E10, but gas with double the ethanol is a different story. “Somebody needs to be honest with consumers,” Kolb says. “These [marine] engines are not designed to accept that fuel.”

And what about E85, the fuel that’s beginning to stake a claim at your neighborhood gas station? (The number of fuel stations selling E85 reached 1,200 as of September 2007, according to the U.S. Department of Energy.) A marine engine running on E85 would “quickly burn up” due to the increased levels of oxygen in the fuel, McKnight says. Marine engines lack the sophisticated electronic control modules to handle this type of fuel.

“If you have a campfire along a river and a big wind swoops down the valley, the increase in oxygen is going to make that fire flare up,” McKnight says. “That’s what will happen with E85 inside a combustion engine. It will simply burn up.”