I started building this engine about 8 years ago and could never get it to go.I put it aside while I built two Rupnow engines which fired first go.I returned occasionaly to the centaur but had no joy ,I got the exhaust valve to seat but fuel was being expelled through exhaust ,leading me to believe that the input valve wasn't seated.The other thing was that I had this valve sliding up the shaft which I should have been part of the shaft,this I corrected.After reading an article on the forum about centaur timing I changed mine to suit and today it ran for the first time.What a trial this has been all down to my faulty workmanship,now to get that peskey coffe cup hot air engine running.
Frank