We have a 1922 narrow gauge 7 ton Plymouth DL-2 at Ardenwood. Like the loco described it has a 4 speed transmission with a separate reverse.

We normally use 2nd gear, but in 1st it will start an 8 car train (10 and 15 ton narrow gauge cars), even more with sand. While it takes practice you can shift gears... you need to understand a crash box and have patience, but it can be done, as you work towards a top speed of 12 miles an hour in 4th gear. That is much faster than it sounds.

We tend to scoff at such primitive locomotives, but, in 1922 our loco meant a railroad could move a small train of full size narrow gauge cars without firing up a steam loco. Our loco has an electric starter,but in a museum setting its useless, it might work on a new loco being used daily. Even without the electric starter it can be reasonably started and be available for use in 15 minutes.

Ours was purchased for an industrial railroad for about 6 times the cost of a working used steam loco. It was successful and the railroad soon purchased a second.

These locos seem like toys, but in their time were effective tools.

I'm curious to see of anyone has tried shifting with them, which is a blast in itself. I know that in 1st, is rather slow, so shifting to 2nd is nice to get it moving a bit faster than a fast walk with a load. I've seen our Plymouth in 4th doing around 18-20mph wide open with a flat car, and that big Climax 4 cylinder just sings.

Dave Loyola
Niles Canyon RR

Hehe, I don't think that at all, having seen the Southern Michigan Railroad Society's success with their Plymouth (as opposed to trucking an RS-2 onto their landlocked line, their other choice at the time.)

As for syncing engine to tranny, seems like a gadget could be built with a shaft rotation sensor on each side of the tranny, and a row of LEDs to tell you how close you were to sync.