I did a RYA Powerboat course this week...part of a Safety Boat course I’m doing for my sailing club. It was interesting that they recommend disposing of fuel in the boat tank if it has been standing for over a month because of water content due to the Ethanol. Seemed a bit extreme to me as they have separation filters between tank and engine but they say they need 100% reliability and won’t take chances.
Or they could go to the nearest Airfield and buy 5 gallons of AVGAS U/L. The international standard for aircraft fuel requires a 12 month "storage" life.
