This thread reminded me of Michigan. My grandfather had a dairy farm from after WWII until early 1970's. As a kid a JD was what I learned to drive way before getting my drivers license at 16:
http://www.gallentine.org/tractors/B40-2.jpg
To start it, you had to turn over the large flywheel on the side. It took a strong man. Fortunately they had a hill near the barn where he parked two of them. You just released the brake and rolled down until you got enough speed and let out the clutch. If it did not start by the time you reached the bottom,
I heard it from my dad
JD's sounded like a thumping Harley.