Flying Phil
Established Member
- Joined
- 18 Apr 2016
- Messages
- 1,932
On steam locomotives, with coupled driving wheels, the crank pins are arranged at 90 degrees side to side - "Quartering" so that the power strokes are evenly spaced (and the coupling rods do not bind?) with two or four cylinders. I am not sure what happens with three cylinder engines and especially when the centre cylinder is inclined relative to the outer cylinders (Bulleid pacifics etc.) are the three crank pins at 120 degrees?