You could also try adding some gas line antifreeze with isopropyl alcohol to the fuel. If the fuel picked up moisture from condensation the isopropyl will combine with the water and allow it to burn. I use the Stabil stuff for storage and it works great. Never had a problem with 2-cycle or 4-cycles after months of non-use. It also keeps carb diaphrams pliable.
Gary in NH
46 taps with buckets, a small homemade RO , two propane fired burners with two stainless steel restaurant pans for pre-heater and evaporator.