Got an exmark with 1500 total hours on it. First engine threw a rod and I got them to put a brand new engine in it (under warranty). So I would guess the new engine has 800-1000 hours. I have had to belt pulleys breake in the past month. They are breaking off right in the middle. Aside from the engine and belt replacement there may not be much more that needs replacing. What are your thoughts? With a mower getting up in hours is it time for a new one?