This machine was sitting at a thrift shop, a handwritten note suggested it was a steam engine. Hmmm. two single action cylinders of different diameters, no valve gear at all.
It's almost certainly not a steam engine but possibly an homemade experimental heat engine of some sort? There is a propane burner in a rusty box (below) that fits around half of the larger cylinder, the other half of the cylinder is surrounded by a metal trough, maybe with cold water?
We applied a few pounds of air through the valve on the small cylinder and the flywheel turned a few degrees but no joy...
Any ideas?







