Originally Posted by Limey Linda
In the US the % ethanol must be declared by a sticker on the pump. Have not heard of anywhere selling more than 10%. Generaly the higher the octane the lower the ethanol. It still makes me very nervous of damage caused to engines, which is the big risk not leaking tanks.
The disintegrating glas fuel tanks were from a specific era (generally, I believe, the 60's and early 70's.) Prettty common on Bertram and Hatteras boats. As someone stated earlier, it's believed that the vinyl and polyester resins break down with exposure to the alcohol.
Modern fiberglass resins should not be a problem.
I believe the alcohol sticker thing is only mandated if 10% or over. Not sure about that though.
The alcohol is added as an oxygenator (not, as many surmise, to reduce the amount of gasoline per gallon as a fuel saving ploy); it is a replacement for MTBE which has been proven to remain in the environment for a lot longer than is healthy. Alcohol burns less readily than gasoline, so it should raise the octane rating of fuel (octane rating being the "explosivity" of the fuel mixture.)
There are several problems with ethanol, besides the disintegrating fuel tanks: fuel line composition must be alcohol tolerant or they fall apart; the alcohol may dissolve accumulated sludge and such that is not affected by gasoline - this then clogs filters and fuel systems; the water absorbed by alcohol may affect aluminum fuel tanks, especially if it separates out (which is not necessarily attributable to ethanol exclusively; you can get water in a straight gasoline as well); reports of phase separation causing excessively lean, low octane fuel mixtures or complete water blockage; etc.
The article referenced was pretty vague about just who was included in the class-action suit; I'd be surprised if they simply lumped everyone in, as it would be tough to prove the damage was caused by ethanol on most newer boats.