Got out my John Deere tractor last night just before dark just to mulch-up some leaves motor ticking like crazy, checked oil, oil level was fine. So my thought was I'll fix your damn ass. I gave it a swollow of Marvels Mystery Oil , a shot in the oil & a shot in the gas. Went in house to get something , By the time that I came out noise was gone! Brother I mean " GONE " motor was purring like a Kitten!