The use of E10 Ethanol in fuel has been a subject of concern for years. Many tests and studies have been conducted, but few conclusions drawn. One thing is clear; E10 Ethanol is here to stay.
Most manufacturers have found ways to handle the E10 Ethanol blend. Recent concern is the push for E15 Ethanol. Test reports regarding E15 have indicated it will create problems that manufacturers are not certain they can overcome.
The suggestion of using straight R90 gasoline has its problems. Vessels that have run on Ethanol should not switch to R90. After extended use of E10, strong odor of gasoline fumes has been noted when fueling automobiles with straight R90. Gasoline fumes that accumulate in the bottom of a boat’s bilge create a danger of explosion.
E10 Ethanol causes deterioration of rubber fuel lines as well as gaskets. It is important to renew the old practice of running your blower at least five minutes before you start your engine. Do not depend on fume detectors; they can fail.
- If your boat was built before 1990 and your rubber fuel lines are soft or brittle, it is suggested you replace them with the Coast Guard approved J1527USCG type A2 or A1-15 flexible fuel lines.
- Coast Guard approved, non-metallic fuel hoses must be date stamped by the manufacturer. When examining your fuel line, look for the date stamp and replace if expired.
For boats that are laid-up, most manufacturers agree fuel tanks should be filled to approximately 90 to 95% of capacity which leaves room for temperature expansion. A good marine grade stabilizer should be added.
- Run your engines and generators then shut off the fuel supply and run to a dry stop. Be sure to change water separators and fuel filters. There could be water in the containers that may freeze and crack.
- Do not cover your fuel vents while in lay-up. Fumes can build up in the bilge creating an explosion hazard.
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What about using fuel additives with E10 Ethanol. Is there anything you can add to prevent the deterioration of rubber fuel lines as well as gaskets?
We allow this kind of crap to happen. I am a 50 yr mechanic (retired), but I still spend many hours each summer rebuilding carburetors for my friends. Ethanol is destroying all the rubber components in these carbs and fuel lines. When a few people in the right places come to harm (read boats catching fire or exploding) maybe something will be done.
This summer I found a source for straight gas and the improvement in performance is amazing. I gained 3knots in a 47 ft cruiser with 454’s plus easier starting and smoother idling. Talk to your senators and get something done.
Yes,my mechanic several years back use to test for Mercury and race Mercury out boards. He now has his own shop in Bridge City, Texas. Its Burton Marine Service.
Thank you for that important article, with that I can go to my boat engine mechanic and ask the right questions that I need to ask.
Also, you do not get the milage or distance out of Ethonal, you will have to plan the trips better.
Welcome to the new America.. Big brother also knows what’s good for your boat.
It’s not Big Brother, it Corporate Agriculture cramming this corn-fuel down our pipes.
It is big brother and its heavily corn fed subsidies. Remove the subsidies and corn fuel goes away. All under the guise of being “green” when it takes 30% more energy to produce. An oxymoron.