Forgot to mention -

Ethanol gasoline plays havoc with cellulose fuel filters. If you see trash in the carb during tear-down ...

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The test was done exactly as Ted reiterated,but I took the "waterline" to be the lowest line on the glass, not the 0 line, but below.  Instructions say the amount of water would be about one teaspoon, and I measured one teaspoon out.   Will try again with water at 0 line.

Assuming the test was done correctly, there was no ethanol in your gasoline test sample.  For that style of tester, water is added to the zero mark, then gasoline added to the fill line that’s close to the top of the cylinder, the cap is installed, shake for approximately five seconds, and then let sit for sixty seconds.  If any alcohol or ethanol is present, then it will show up above the zero mark as a distinct phase shift between the water and gasoline.

Lorena, Texas (South of Waco)

The tester should have instructions.  If the test was done correctly and the result corresponds with 10%, then that should be what it is.
My thought is that the 10 mark is 10% but can't be sure without the instructions.


Lawrenceville, GA

Update to this thread;
  Received my fuel testers kit and here is a picture of the results.  Seperation line is at the " 0" mark, and bright blue.  This was gas from  local station, supossedly 10% ethanol, and stored in plastic 5 gal fuel container about a month.  Sample was "straw colored" with no sediments.  So, as  far as everyday gas station fuel this is "normal" (10% ethanol) as advertised at the pump? 

... supossedly my local Yacht Club has ethanol free gas,

There you go, marine fuel and aviation to some extent. There are also stations that sell ethanol free but they are usually in heavily agricultural areas. Farm equipment can't run off it either.

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To help eliminate percolating I installed 3/8” phenolic spacers under both my carbs. I live in So Cal and 2 weeks without running is still one full pump to squirt both carbs and set rear choke. 3 weeks is some cranking. I’ve never checked the fuel but will do so now 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Well, we will find out the quality of the gas I've been using.  Ordering that fuel test kit today, and supossedly my local Yacht Club has ethanol free gas, and I will test that also to be sure.  Will report the findings when it happens.  Thanks again.

Usually, engine shut-down and resultant heat soak causes the fuel bowl/feed line to pressurize and possibly lose fuel through percolation or actually being forced out of the bowl into the throttle bores. Carb designs vary.. Ethanol will dissipate more quickly with heat and of course will evaporate with open bowl vents over time.

Ethanol laced gasoline is meant for today's technology with EVAP SYSTEMS. With a vented fuel tank, the fuel is constantly drawing moisture from outside air. And of course if you are buying cheap gasoline, you have no idea where it  is from or how it was blended.

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Thanks KULTULZ,
  I appreciate the link to the fuel test kit, I'm on it.