Testing for Ethanol in gasoline

[Gerald]

Danny..... When I read the info on the test kit, it said that it would "change" color if there was ANY Ethanol in the sample. My concern is would the "test" show positive for very small amounts of Ethanol?

Note: I have considerable experience running titration test.

Example:

1/2 gallon of 10% Ethanol fuel left in a 10,000 gallon tank of gasoline.

That is 50 ppm of a 10 % mixture. So that would be 5 ppm of Ethanol in the sample.

Question...... would that be enough to make the color change and show a positive? Maybe 1 drop would make the color change on very small amounts of Ethanol and it would take several drops to make the color change in 10% Ethanol fuel.

I also, I don't think the "Test Kit" instructions said anything about sample size which would make some difference.

I would guess that 5 ppm amount of Ethanol would not hurt an outboard engine.