Eight-year-old farm boys like Jack dream big. Jack spends summer days sitting on the coal box of Pa's Advance-Rumely Universal steam engine wishing he was big enough to help thresh wheat. Soon, pictures in Pa's tractor book have Jack dreaming of a 16-30 Rumely OilPull belted up to an Ideal separator on Pa's back 40. Before long, Jack comes up with a secret plan to check out a Rumely OilPull. With a little mischief and the help of an unexpected friend, Jack learns a lot about his favorite tractor and becomes a little Rumely man.