stated brand new, did the 5 hour oil change, went to Amsoil Synthetic and kept using the synthetic from 5 hours to 67 hours. Just in case the synthetic kept it from breaking in , it drained it today and went back to dino oil in hopes the rings just need seating , but synthetic of no synthetic, its been 67 hours and a light white smoke still comes out the exaust. Better seen in bright sun light, not that obvious but I can always smell it. Thougth it might be running rich with a dirty air filter, changed it today and it made no difference. I notice if I back off the throttle it gives a one second puff of smoke which should signify something but I can't remember if it mean a bad valve guide or not. Any ideas, head gasget, bad gas, unseated rings, exaust recycle doo-hicky, what causes a light constant stream of white smoke out the exaust that gives one puff when you back off the throttle or is this normal for Kohler?