THE FOLLOWING IS AN EASY ETHANOL TEST . IT DOESNT GIVE YOU A PERCENTAGE OF ETHANOL ONLY A TEST FOR PRESENCE OF ETHANOL BECAUSE IT WILL EASILY BLEND WITH THE WATER. LET SOLUTION SIT A FEW HOURS . IT ISNT A CHEMICAL INSTANT TEST .
The following test can be performed to determine the presence of ethanol in gasoline.

On a test tube or olive bottle, make a permanent line about two inches from the bottom.

Fill with water to this line, then fill the tube to the top with gasoline.

Cover the tube, agitate it then let it stand.

Ethanol mixes with water and the two will separate out together. Therefore, after mixing the water and the gasoline, if the water level appears to have increased, then the fuel contains ethanol and should not be used.

Ethanol fuels can damage the rubber and aluminum components of your aircraft fuel system. Ethanol increases the volatility of fuel, and hence the possibility of vapor lock also increases. Ethanol may vent off at altitude, reducing both range and octane. For these reasons fuel containing ethanol must never be used in airplanes.