THe 25hp Kohler on my Dixon has been using oil for some time now, I noticed it using quite a bit at around about 200 hours, but of course I didn't take it in... Well now I have 900 hours on it and for the last several hundred Iv'e been adding oil about every other day, usually 8 to 10 ounces at a time! The engine dosn't visibly smoke other than at start-up sometimes. The exhaust does smell strong at times too. Anyway, I had the machine at the dealer to get a couple things fixed and I asked them to check it and told them how much oil it was using. I was told it was totally NORMAL! "Every engine is different" he kept telling me when I explained that I have had about 6- 22 to 25hp engined over the years and NONE have used this much oil. Even my backup machine with 2500 hours dosn't burn this much oil. They did a "leak down" test and found that I have one intake valve leaking slightly, but everything else was within specs. He said that the intake valve wouldn't account for that much oil useage, but then told me again that "it's normal". Engine warranty wouldn't cover any repairs at this point so I told them to just forget the rebuild and I'd keep dumping in oil till winter and then decide what to do. I was using mobile1 syn. from 50 hours up till about 800, but frankly I'm tired of spending that much $$ on oil that's just dissapearing! I just swiched back to cheapo 10w30. Any opinions? Thanks!