The locomotive hit me with a lot of complicated technical things that Chinese workers were able to cram into such a small locomotive.
Among them: full Stephenson valve gear with D-valve, feed water axial pump, whistle, Roscoe lubricator, water gauge, sprung axials etc.
The operating time from one gas filling is approximately 20 minutes.
Unfortunately after several times the pressure gauge is wreck, I had to replace it with the Regner pressure gauge. Also I added a two-channel radio control to the reverser and the throttle, the Goodall valve by Regner and WeeBee safety valve. In the cab I added the figure of engineer.
Some photos:





In the cab:

Stephenson valve gear


Cylinder

Feed water pump

Video with action of the valve gear



