Clockwork train - dead

  

1   The train body is 3 7/8" -  9.95cm long. 

The large wheel has the clock spring behind it.  

 The spring wheel cogs drive the middle wheel.

The wooden circles show where.

The Different Types of Train Wheels

The three types of wheels: The first thing to recognise is that steam locomotives have three basic types of wheels; Leading Wheels, Driving Wheels and Trailing Wheels. All locomotives have Driving Wheels but not all have leading or trailing wheels.  

source - look under People also ask.

Leading Wheels. These aren't powered and sit in front of the driving wheels. 

 Driving Wheels. Driving wheels move a steam locomotive through pistons and rods.

.............

________________________________________________

Piston valves are one form of valve used to control the flow of steam within a steam engine or locomotive. They control the admission of steam intothe cylinders and its subsequent exhausting, enabling a locomotive to move under its own power.   pagetop  Watch the useful video here.