If you ever have a chance to look at WI&M #1 in Potlatch, Id. it has the same "Franklin Universal Valve Chest" conversion though the motion is stephenson.
At least on the engine in the attached photo, the piston valve shaft appears to be eccentric to the piston and it's bore in order to be closer to lower height of the original slide valve shaft. It also appears on this engine that an offset has been bent in the valve shafts to further correct the height difference. Early photos of the engine when it had slide valves show the shafts perfectly straight. I wonder if this was a common procedure when making the conversion.
Edited 1 time(s). Last edit at 05/31/2014 06:01PM by J.B.Bane.