Location: The Yahara Chain | From Boats.com
So why are we having trouble with E-10 fuel today?
"Ethanol is a fabulous solvent," said Don Schultz, who retired from Mercury Marine in 2001 after serving 14 years as that company's leading expert of fuels and lubricants and today is an independent consultant to the marine industry. "So it's going to dissolve accumulated deposits in the fuel-supply system, and those could end up in a fuel filter or elsewhere in the fuel system if they get past the filter. Ethanol also loves water, it just sucks up moisture. This is not a big problem in the sealed fuel system of a modern car, but most boats have an open-vented fuel tank that breaths and introduces humid air to the fuel tank. This can create the formation of strong organic acids as water combines with ethanol and other elements in the fuel, forming sludge and corrosive compounds."
Here is an explanation of phase separation.
NEWS From BoatU.S.
Boat Owners Association of The United States
880 S. Pickett St., Alexandria, VA 22304
BoatU.S. News Room at http://www.BoatUS.com/news/releases.asp
FOR IMMEDIATE RELEASE
Press Contact: Scott Croft, 703-461-2864, [email protected]
Date: October 23, 2006
WHAT YOU NEED TO KNOW ABOUT E-10 ETHANOL FUEL AND WINTER BOAT LAYUP
This spring and with little prior notice, recreational boaters in most parts of the country were introduced to gasoline containing higher concentrations of ethanol, a corn-based additive that replaced a known carcinogen, MTBE. The new fuel, dubbed "E-10" for its 10% ethanol content, unfortunately has the ability to attract greater amounts of water and "phase separate", or form two separate solutions in the gas tank, usually over a long period of time. Once this happens, the engine won't run and internal damage could occur. With the lengthy winter lay up period upon us, many boaters are asking how they should store their boat over the winter to prevent fuel problems next year. The BoatU.S. damage prevention newsletter, Seaworthy, tackles the problem in its October issue and has these recommendations:
• Once phase separation occurs in E-10 gasoline, additives and water separators can't help. The only remedy is to have the gas and ethanol/water professionally removed from the tank.
• With any fuel that sits in a tank for a long time, it's important to add a stabilizer. But understand that stabilizers do not prevent phase separation.
• E-10 has been a fact of life in certain areas of the Midwest for over a decade and there have been relatively few problems. The best practical recommendation learned from marina operators in the region is to top off a boat's fuel tanks to about 95% full, leaving room for expansion. A tank that is almost full limits the flow of air into and out of the vent, which reduces the chance of condensation adding water to the fuel. Draining fuel tanks of E-10 gas, while completely eliminating any chances of phase separation, is potentially dangerous and an impractical solution.
• Whether you believe your boat's fuel tanks are half full or half empty, leaving a tank partially filled is a bad move. A Midwest marina owner confirmed that phase separation problems typically occurred when boats were stored over the winter with tanks only one quarter to one-half full. In the summer, infrequently used boats with partially filled tanks are also prone to phase separation.
• Never try to plug up a fuel tank vent to prevent moist air from entering a tank. Without room to expand, the additional pressure could rupture fuel system components. |
