Ya see I'm the guy who actually had a tractor sit around Since April of 1999 and didn't try and start it until 2010.
Why do I know the exact date. I sued the dealer that month for not returning my tractor and inflating the work invoice without my approval. He lost the case, but in the meantime I bought a new tractor so when he returned my old 1980's Kubota it just sat. It sat long enough that weeds grew up through every crack on the tractor. Up through the seat area, up through the engine compartment etc. It was looking good as a lawn ornament.
Then I decided to either sell it or just junk it. So I dragged it out of the weeds, flat tires and all. Cut out the weeds, filled up the tires replaced the battery and shoved an old screw driver in the key hole to start it - knowing full well nothing would happen. After all it has almost 15 year old fuel in it.
She chugged, she coughed, she puffed, then she fired right up. The four of us standing around laughed and applauded at the same time.
I checked the fluids, topped them off, put some fresh fuel in and off I went to plow a field for the next eight hours in 100 degree temps.
I got off the tractor beat, and that old Kubota was begging for more.
Well that old Kubota is still around. I didn't have the heart to get rid of her. One of these days I may actually change the engine oil.