The governor/fuel control needs help. It sounds great, but it is running very badly. The cylinder closest to the flywheel doesn't bring much to the party. Putting a load on it would also smooth it out. If it ran smoother, it would probably bring the cylinder temp up and not smoke as much, but it would not be nearly as interesting to hear.
Following the You Tube thread, I saw great vids of an Erie B steam shovel at work and several videos of Big Muskie, the world's largest dragline.