single cylinder rotary valve engine design question

[Mike Rometer]

I am curious as to the function of the small 0.173 hole that goes through the valve front to back. .

Some sort of valve balancing, like slide-valves?

[wsmcycle]

Yes Mike, I agree, a valve balancing feature. I suppose the designer thought the valve would leak so little that no lubricating steam would get to the "back/opposite" side of the valve and that it would need the passage to supply the needed lube 360 degrees.

I came to a revelation this morning while looking at the valve. Someone must have re-turned the taper on the OD of the valve and that is why it has to move 0.50 toward the exhaust end to fit the valve-block taper. I just couldn't (and shouldn't have) believed the valve could wear that much. I assembled the engine with the valve moved toward the exhaust to fit the tapers and it ran very well on compressed air. I am going to shorten the exhaust end of the valve where it protrudes into the exhaust coupling so I can screw in a close nipple and then a coupling.
Also, because of the larger size of the tapered valve on the actuator end than the exhaust, there is a (pressure/area) force directed toward the actuator end. This means the valve is NOT being forced against the exhaust end as I had thought and so, I don't need a stop on the exhaust end of the valve.

[wsmcycle]

I have put a video of the rotary valve engine on youtube. See it here https://www.youtube.com/watch?v=VP82I4e ... tion=share