I couldn’t resist the temptation to see if the engine would turn with the newly finished valve gear.

I hadn’t finished the reversing gear and used some bungies to hold the expansion links and set the eccentrics by eye, and after some tweaking of the valve rod lengths to get the valves something like central, applied some compressed air (via a manifold to make it a high pressure twin)… and it turned (smiles all round)…

Thankyou YouTube for de-shaking this vid!

result!