About 56 yrs ago, I was in the MM dealership with my dad, fetching parts for his tractor. I spied a new tractor on the show room floor and wanted to sit on it. Dad asked if there was any way I could start it or otherwise mess something up. They said no, it was hard to actuate the starter so they said it would be fine for me to get up and play around on it. Well, I got up there and was steering it, pulling the levers, bouncing up and down and having a good time. I spied this knob down along side the operators platform that was in just the right position for me to put my 4 year old foot on. I did and gave it a push and it started! Not only did it start, but the throttle lever was pulled down for full throttle! Talk about getting the attention of some grownups, I did! Luckily, it was in neutral and it was shut down rather quickly. I'm almost 60 and I remember that like it was yesterday. And it was a diesel, too. All we had were on butane, except for the little Massey 30 or 35 and it was gasoline. The MM we had was a U and I think it had more to the model, but can't remember. I do remember the hand clutch.