Hey guys! I also posted on Honda forum but maybe there is more help here. I am nearing the end of my first rebuild project on a Honda hrm 215 push mower w/ a Gxv 140 engine. I got it back together and it ran fine but started smoking a little from air box breather hose from engine block. I ran it with the air box off so that I could make throttle and governor adjustments at the carb. I stopped the engine and it stopped dead. The piston had seized. I freed that up and noticed the oil was gray in color. Stupid me I ran it again to see if it would still start. It did and I consequently broke the connecting rod and a couple teeth on the cam were gone (maybe melted?). I have new parts coming but am not going to restart engine until I know what is going on. It seems to me like the oil is not circulating properly. It is my understanding that the oil defense pipe (the little black piece that snaps into the oil pan) at least aids in oil circulation. It only snaps in one way, though. Any guidance would be appreciated as the lawn is getting long! Thanks.