Boaters in colder climates are starting to winterize their boats - or they're at least thinking about it. Considering the problems that ethanol-blended gasoline can cause, proper preparation of the fuel system and engine is a critical step in preparing a boat for winter storage.
Gasoline with 10 percent ethanol (E10) has led to such problems as the disintegration of fiberglass fuel tanks, the gumming up of fuel lines, and piston and valve failure. Two properties of ethanol, in particular, can cause problems in boat fuel systems and engines. First, ethanol absorbs moisture - more so when it sits unused for long periods - so it can cause water to collect in your fuel tank and fuel system. Second, ethanol is a solvent. E10 can loosen debris in the tank or fuel lines and allow it to reach the engine.
"Fuels with ethanol are not going away," says David Meeler, Yamaha's product marketing information manager. "There's very little we can do about it except try to mitigate the risk as best we can and educate people the best we can."
Meeler and other engine manufacturer representatives recommend using a quality fuel stabilizer and conditioner. Yamaha recommends its own product, Yamaha Fuel Conditioner and Stabilizer Plus. Others include Marine Formula Sta-Bil Ethanol Treatment, Star brite Star Tron Enzyme Fuel Treatment and ValvTect Ethanol Gasoline Treatment.
The stabilizer should be added to the fuel tank before the seasonal layup and the engine should be run long enough to ensure that the stabilized fuel courses through the entire system. Stabilizers inhibit corrosion and help prevent phase separation. Phase separation occurs when ethanol-blended fuel surpasses a certain water saturation point and the ethanol and water separate from the gasoline, forming a layer at the bottom of the tank where the fuel exits and heads to the engine. The gasoline remains on top of the ethanol-water layer.
Some engine manufacturers, including Yamaha, recommend adding a second treatment to the tank before layup. Yamaha Ring Free Plus removes carbon, gum and varnish and helps keep the fuel system clean, according to the engine manufacturer. Several other companies also sell this type of carbon-cleaner treatment.
Experts say stabilizers targeting ethanol and carbon-cleaner treatments should be used during the boating season as well, not just before winter storage.
Read more at http://www.soundingsonline.com/news/dispatches/612-oct-14-2010/267622-ethanol-a-winterizing-guide