Is your mower blowing seals left and right and making you post on open forums complaining about the reliability of the mower itself when it's the actual engine? I didn't think so..... Are you complaining how others are getting more hours and service life out of their same exact brand mower? I didn't think so... If you're not getting the same results or better than others, how could you consider that you're doing everything right? I'm just simply trying to negotiate reasons why certain things happen. All periodic maintenance recommended in service manuals are under ideal conditions. Just as speed limits are posted for ideal conditions. Just because the curve's recommended speed limit is 45 doesn't mean you can take it with a backhoe at 45. If you're having issue with your engine you should step up your recommended maintenance schedule that is all. Yes to the OP you may have done everything right and got handed a basket full of lemons. The fact is most manufactures only use three brands and the top two used without a doubt are Kawasaki and Kohler. Yes Honda and briggs make good if not great engines they're just not found on most popular models and usually mean a sacrifice in order to get these engines. Whether it be monetary or model it usually is still a sacrifice.