I have a 5 HP (Briggs) rear tine tiller that belonged to my FIL, I hadn't used it for at least 5 years (probably longer) since I had a tiller for my JD 74-112. Replaced the 112 with a 314 a couple of years ago, but don't have a tiller for it because of the expense & won't use it enough to justify the $$$!
Meanwhile, the MTD sat in the shed until the tires went flat! Got it out this morning, put tubes in the tires & took it to the shop. The tank was still half full of old gas, so I treated it with Star Tron. I took the air cleaner off & sprayed some carburetor cleaner in, a few pulls of the rope & it fired, few more & it was running after all these years! After it cooled, I pressure washed it, then restarted it & ran all the old gas out, refilled with fresh (treated) gas & put it in the shed --- for now. ~~ Lowell