Ethanol And Your Outboard

By David Randall, the Prop Boss

In the spring of 2006, most gasoline refiners switched to ethanol-blended fuels. The reason they switched was to reduce ground water pollution (and cancer causing risk) associated with MTBE (Methyl Tertiary Butyl Ether), the chemical that had been used in the past to oxygenate fuel/gasoline. Gasoline mixed with 10% ethanol is now in widespread use in most U.S. States that have recently banned MTBE.

While ethanol (alcohol) is safer to the environment than MTBE, recent concerns have been raised by the outboard, boating and marine industry, since high levels of ethanol is known to cause serious damage/problems in most engines and motors. E.G. outboards, airplanes, lawn mowers, farming equipment… As increased ethanol-blend gas is mandated, we expect outboard motor breakdowns will rise.

Briefly, ethanol’s adverse effects to motors include stalling, all types of performance issues, deterioration of engine parts, rusting, clogging of fuel filters and carburetor jets, contamination of the fuel system, release of gunk and sludge throughout the engine and eventually engine death. Boat owners, especially in New York, Connecticut and California, who unknowingly used gas with high levels of ethanol (sold since Spring 2006), have been reporting major engine problems associated with the use of these new ethanol-gas mixtures.

Ethanol has always been banned for use in airplane engines, due to the well-documented problems it will cause. The FAA issued another warning this month against using ethanol-blend gasoline in airplane engines. (November 2006 – See information source # 4 at end of article). The very dangerous effects ethanol fuels have on marine engines is similar (and for the same reasons), known for a long time in the aeronautic and farming industry. The FAA and other agencies bans/ exempts use of alcohol-blended fuels on aircraft and farming equipment. Recent fuel testing revealed that the percent of alcohol (ethanol) present at the pump varies widely. Below 10% ethanol is considered acceptable by most marine engine manufacturers. All agree, that ethanol above 10% will cause damage and/or performance/ running issues with outboard engines.

We sell a great additive, Star Brite Star tron, available in 8 fl. Oz., 16 fl. Oz., and 32 fl. oz. from Randall Marine and many other marine supply retailers.
This additive has been proven to offset many of the challenges we are seeing in relation to outboard and inboard motors. One fluid ounce of the additive treats 15 gallons of gas. A little prevention can prevent a lot of cure.

Now, Let’s Go Fishing after stopping at Randall Marine.

By David Randall, Randall Marine. Originally published in SWGA Edition of Coastal Angler Magazine.


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