I have new cylinder, new ring, and just broke it in runtime 20 minutes very rich. AFter engine stops appears to have little/no compression. After cool down has some compress, on fast flip of propeller-but seems to leak on slow spin. Head bolts tight. Wondering, does ringed engine normally have lower compress, due to split in ring? Provided that head is bolted tight and no leaks detected around glow plug. Would a new piston help? ABC engines seem to have firmer compression in my experience. My address is
jwvoth1@msn.com Engine seems to run fine, but not fully broken in yet. Plan to run at least 1/2 gallong and see how compression improves.