Doctor Emmett Brown was pushing a DeLorean time machine up to the train station while Chuffy was there.
"Hello? Is anyone here?" Emmett asked.
"Hurr! Arn't you that mad scientist with the time machine?" Old King Coal asked from inside Chuffy's boiler.
"Great Scott! You know who I am. That's quite an odd coincidence. It's also intriguing how you live inside this locomotive of yours." Doc gasped.
"That's because I am Old King Coal! And this is Chuffy, my train."
"That's intriguing. Anyway, I came here because my time machine has run out of gas while traveling through the space time continuum, and there isn't a gas station anywhere around here."
"NO! Chuffy is not going to push your crazy car! The last train that did that back in 1885 fell into a ravine! I won't risk Chuffy's life for a stupid car!" OKC stated, being unreasonable.
"Actually, that's not why I'm here. I need some coal that I can convert into ordinary gasoline with one of my latest inventions, since I've been working on a way to be able to come across gasoline in any time period, even in the Old West."
"Are you going to go back in time to stop Chuffy's ancestor from falling into that ravine?" OKC asked rhetorically.
Emmett sighed. "You must really be obsessed with trains. Especially this one. speaking of which, did you know that I built a flying train time machine?"
"Hurr! Just take what you need and leave!"
Without another word, OKC threw a lump of coal out of Chuffy's boiler, which landed in Emmett's hands as he pushed the time machine away, personally getting tired of Old King Coal's remarks.