Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Very nice engine. I have a couple like it myself.  The one brush is on the armature contact the other one is on the shaft itself. The one on the shaft is the ground for the lamp post. The wire goes from that brush to lamp post base. Also noticed it has the square throttle valve. If you remove the plate on steam chest all 3 holes are there. I guess Jensen figured it was easier to just thread and put screws in all 3 holes instead of making the plate to cover them. I would say it is late 30s