Well.......What the heck!....This mower only has 10hrs. on it & now it smokes ......A LOT!... every time I start it up. Now I changed the oil at 5hrs. like the manual said, with the Kohler oil & was very careful not to over fill . It only does it on start-ups & then stops after about 20 seconds......BUT......The smoke is very thick & heavy. Is this normal for Kohler engines??? Do they all smoke like this? I have never had a mower do this.