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Info on E-10 in marine applications

Boat Engine Dangers and Precautions

Many Boat Owners have unknowingly used gas, blended with unsafe levels of ethanol alcohol. Running on gas with over 10 % alcohol in a marine engine will cause performance problems, and can also cause permanent damage to your marine motor and repairs due to this damage may not be covered under the terms of your warranty. Understanding the dangers and effects of alcohol gas, in addition to following all the necessary marine fuel system precautions, is now necessary to avoid any problems with E10 gasoline. There has been much controversy, misinformation and confusion since the recent (2006) increased distribution of ethanol gasoline in the United States. Recent marketing gimmicks by some fuel additive product companies have confused boaters even more. These ads falsely claim their new products can "fix" or repair ethanol water-contaminated fuel...Phase-separated fuel can not be fixed, it must be discarded. Even high level, reputable government authorities, have recently published information that conflicts with previous articles and bulletins written years ago on ethanol. Marine manufacturer fuel recommendations (eg. owners manuals), which in the past, often warned against using alcohol fuels, now document that up to 10 % ethanol in gas is acceptable. As more people are using E10, the necessary precautions and dangers are becoming more apparent and better documented. Boaters looking for instant answers and solutions will not find them. Increased knowledge and following all the necessary precautions can spare you from most of the inconvenience and problems with alcohol gas. All reputable authorities agree, that running on ethanol alcohol above 10% will cause motor damage and/or performance issues with gas-powered engines, and it is always unsafe to run on contaminated fuel.

Prevention: Your Best Weapon Against Ethanol Gas

 E10 is a gasoline blended with up to 10 % ethanol alcohol and is now in widespread use in the U.S. Ethanol, ethyl alcohol, is made from corn, sugar and other grains. Alcohol is an excellent cleaning agent, solvent, anti-freeze and most important, ethanol is hygroscopic, meaning it will absorb large amounts of water. Government regulations and laws for ethanol fuel use and labeling differ from state-to-state, and are constantly changing. The most serious boat engine problems, resulting from ethanol E10 use, have mainly occurred due to illegal amounts of ethanol (over 10 %) being incorrectly added at the gas station pumps, by the delivery truck drivers. Since using over 10 % alcohol gas is dangerous, it will invalidate all marine company engine warranties. Many ethanol problems, reported by boaters appear to be due to their lack of knowledge/information on how to properly manage alcohol fuels. Many boat engine breakdowns in recent months are directly related to the mismanagement of E10 gas. Several older engines can not use any fuels that contains alcohol. Eg. Certain fiberglass tanks, mostly manufactured prior to 1992, will decompose from alcohol. Fortunately newer outboard engines (past 5 years) have been designed to be more compatible with alcohol fuels.

 Why Do Boat Engines Have More Problems

 Boaters, often store gas in tanks longer than recommended for E10 (90 days). Cars, unlike boats, usually replace fuel every week or two, which will successfully prevent the possibility of water-contamination/phase separation. Boat engines live in a water environment. Alcohol is a magnet to moisture increasing absorption of water into fuel tanks. Ethanol's adverse effects on boat motors involve all types of performance issues and disintegration and deterioration, drying and clogging of engine parts. Signs and symptoms of ethanol problems and damage include: Stalling, prematurely worn engine parts, rusting, clogging of fuel filters and carburetor jets, release of gunk and sludge throughout the engine, frequent water-contamination/phase separation of fuel, and eventually engine breakdowns and death. Ethanol can cause a motor to run lean on fuel, due to water will not burn, which will take the place of fuel. Vapor lock (fuel starvation) is common when using ethanol fuels. Alcohol fuels are very prone to phase separation, when the weight of the ethanol and water will sink to the bottom of the fuel tank and get picked up by the motors fuel system. (Even small amounts of water can harm the fuel system). The initial symptoms, (of using a higher than acceptable concentration of alcohol in fuel, is usually engine stalling when you demand acceleration (WOT). You'll notice other performance issues, such as increased stalling, misfire, hesitation and difficulty maintaining boat speed during trolling. The long term dangers of ethanol (and other alcohol-blended fuels) are many, including deterioration of parts (rubber, aluminum, fiberglass etc.), rusting, fuel system clogging, and other varied damage to engine parts and components. Older engines are more prone to ethanol alcohol damage. The most reported and troublesome issue with marine engines and ethanol fuel has been regarding the decomposition of certain fiberglass gas tanks. There really is no solution to this issue, other than to replace the tank (very costly, time-consuming project); Lining or sealing the tank, for added protection, is sometimes possible.  

10 Things You NEED To Do Because ETHANOL IS IN YOUR FUEL

1. If possible, try to avoid using ethanol fuel blends in your outboard and marine engines. If you are unable to obtain alcohol-free fuel in your area, you SHOULD TEST THE FUEL YOU BUY to assure the ethanol content is at or below 10 %.

2. Follow engine manufacturer gas recommendations. Check with your marine motor manufacturer and/or check your owner’s manual.

3. Always use fresh, high-quality gasoline and replace it every 2-4 weeks. Always avoid storing gas in tank for greater than 90 days. Remember that gas with ethanol has a shorter shelf life - use it up and replace it quickly. Buy gas from busy gas stations - Fuel turnover is faster, gas will be fresher.

4. Check your gas tank for the presence of water and remove all water before adding an ethanol blend.

5. Avoid running on bottom of gas tank (where most water will sink).

6. Do not mix MTBE (gasoline additive) and ethanol-blended fuels. Run out or remove your old (MTBE) fuel before putting the new ethanol fuel in your tank.

7. Make sure your motor is equipped with a water separating fuel filter. Newer engines have them, other engines may or may not. The installation of a water separator in the fuel line will help with small amounts of water. Some marine engines are also equipped with water sensors.

8. Check fuel system for contaminants and clogging and replace your fuel filter often. Fuel filters should be replaced at least every 50 -100 hours.

9. Keep your engine well-tuned and lubricated.

10. If your engine has an older fiberglass gas tank, replace it. (Check with your manufacturer to see if your tank was designed to tolerate alcohol fuels). Newer fiberglass tanks are double-lined and made of special material that holds up to ethanol.  


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