Just re-ran and tried a zinger 7.5x4 10,500 2 head shims managed to reduce compression slightly to get contra just inside bevel edge
of head insert with my infra red temp gauge it is reading 250 at junction on head and cylinder, seems a little too warm? If compression
backed off we get the diesel miss, It could be ether% may needed to be increased slighty to lower compression and heat. Fuel Clutton
old english mix. It is rock steady and holds rpm martin