This area (upstate NY) has a BIG problem with ethanol in fuel. The ethanol will separate from the gasoline as it ingests moisture and fall out of solution with the gasoline. The end result is low octane fuel, and a layer of water in the tank. Failure to deal with this will guarantee starting issues in the fall. There are 2 popular ways of dealing with this issue, first is to avoid fuel containing ethanol (very difficult to do) or add a stabilizer that has an enzyme that is supposed to maintain the miscibility of the ethanol in gasoline.
Gasoline that uses ethanol is made to a lower octane rating and the ethanol raises the octane level. When the ethanol absorbs water (which it loves to do, think dry gas) then goes through a significant temperature swing (seasonal changes) the ethanol/water blend falls to the bottom of the tank and is often the first thing picked up by the carb. The majority of old style stabilizers only dealt with the gasoline evaporative issues (“light ends” or the main volatile component of gas evaporates readily) leaving a varnish like substance. The “new fuels” don’t survive long enough for this problem to manifest.
The water that sits in the bottom of the tank can rot steel tanks, and will foul carbs when it sits in the fuel bowl.
My advice is:
Treat ALL seasonal fuels with Star-Tron, or similar ethanol treatments.
Purchase only enough fuel for the season, and treat every batch
(you never know when the last seasonal use is going to be)
Treating all the fuel ensures the treated stuff is IN the whole fuel system.
Using a flashlight look into the fuel tanks and see if separation has occurred,
If it has, dispose of the fuel, it isn’t useable. You can dispose of small (less than 2 gallons) in your car, if you
have a mostly full tank.
Drain fuel bowls when possible, and use fuel shutoffs to empty fuel bowls (shut off fuel and run till stall)
This can reduce the amount of muck that will deposit in the jet.
If you have contaminated fuel, and the machine won’t start, or seems under powered, remove the fuel, and replace
with fresh treated fuel, including the fuel bowl. If that doesn’t fix it, you will need to have the carb serviced
replacement needle and seat kits, are available, lets can often be cleaned, DO NOT ADJUST MIXTURES,
they are set by the factory, and adjustment can violate emission laws.
Hope this helps with ethanol understanding, please look at the many online discussions of ethanol in gasoline for more tips to deal with it. Boat owners should be particularly wary of ethanol in fuel. The ethanol can destroy fiberglass tanks as well.
Thanks for your attention,
Chief Apprentice Appliantologist; Apliantology.org
ASE certified Mechanic
Nate Certified HVAC Tech