I have a 2006 Lazer Z Hp with a 27hp Kohler engine on it. I bought the mower off a guy last year the mower only had 75 hours on it. I changed all the fluids at the end of the season last year and now the engine is smoking. When I first start the engine up it will bellow out white smoke then go away I figured this is just condensation. After the engine is warmed up it will smoke a little black smoke not muck though. If I pulse the throttle up and down it will also smoke a little black smoke. When I changed the oil I put Mobil-1 10W30 synthetic in it. I am wondering if it is the synthetic oil that is causing it to smoke. The mower now has 127 hours on it.