Somebody in our club bought a couple of used OS Wankel engines on the internet. He brought them to the field to try them out. He could get one to run without problem, but the other had little or no compression and would not run despite the fact that there was enough fuel. Then he took the recalcitrant engine apart to see why there was no compression. I vaguely remember that there are "square" looking "gaskets" that may have to replaced, but I might be totally wrong on that one, so somebody correct me if I am wrong. These OS Wankel engines are not being produced anymore, as I understand it. PS I certainly would start off with a new glow plug or test the one that came with it.