Tucson has one Carb rebuild shop that does nearly all the rebuilds in Tucson. I was in the shop the other day and spoke to them about this topic. There recommendation was NO. They said the fuel is fine for 3 months and afterwards starts to break down. They said they are finding the fuel stabilizers are combing with the gas additive and creating even bigger issues as the fuel ages. They recommended draining if the Car/Tool or whatever is not going to be used withing 3 months. I currently have a lawn mower & old car that were not started for over 6 months and neither will start. Have confirmed both need the carbs rebuild as they are plugged up with goop from fuel sitting in the carbs. They also said they are seeing tons of rust from the water that accumulates in the pre-ethanol steel tanks. I just changed out my old Jeep's steel tank, needed replaced anyway, with a new Poly tank. You can find tons of info on the Net about how bad, both physically & economically, ethanol is. As a sidenote, I have found my 2 cycle engines with oil in the fuel are not having the aging problem.
rocmoc n AZ/Mexico