Notice: Do not use fuels containing methanol in order to prevent damage and corrosion to the fuel system.

Alcohol-in-fuel can be detrimental to the fuel system components. Alcohol-in-fuel can cause driveability problems such as hesitation, lack of power, stall, no start, etc.

The problems may be due to fuel system corrosion and subsequent fuel filter plugging, deterioration of rubber components, and air fuel mixture leaning.

Various types and concentrations of alcohol are used in commercial fuel. Some alcohol is more detrimental to fuel system components than others. If an excessive amount of alcohol in the fuel is suspected as the cause of a driveability condition, the following procedure may be used in order to detect the presence of alcohol in the fuel. In this procedure, water is used to extract the alcohol from the fuel. If contaminated fuel is suspected, the fuel must be completely drained from the tank and replaced with known good fuel.

Draw the fuel sample from the bottom of the tank in order to detect any water present in the tank. The sample should be bright and clear. If the sample appears cloudy, or contaminated with water (as indicated by a water layer at the bottom of the sample), do not use this procedure. Refer to Fuel System Cleaning .

1. Fill a 100 ml cylinder with fuel to the 90 ml mark.
2. Add 10 ml of water to bring the total fluid volume to 100 ml. Install a stopper on the cylinder.
3. Shake the cylinder vigorously for 10 to 15 seconds.
4. Carefully loosen the stopper to release the pressure.
5. Close the stopper and shake the cylinder vigorously again for 10 to 15 seconds.
6. Put the graduated cylinder on a level surface for approximately 5 minutes to allow adequate liquid separation.

If alcohol is present in the fuel, the volume of the lower layer, which would now contain both alcohol and water, will be more than 10 ml. For example, if the volume of the lower layer increases to 15 ml, this indicates at least 5 percent alcohol in the fuel. The actual amount of alcohol may be somewhat more because this procedure does not extract all of the alcohol from the fuel.