A fuel filter for my Duramax is $45 while a set of injectors is $6,000 It ain't hard to get dirty fuel, especially when you buy it where we do like at gas stations with a diesil pump out back. Your signature is kind of funny, "Don't buy air cooled crap, get diesel." Then your thread talks about air cooled diesel. The leader in air cooled diesel is Dieutz. Mounted to their tractors they're not too noisy. But I tried out a 72" Gravely with a Dieutz motor. They didn't use isolating motor mounts, sound baffels or Dieutz muffler. The noise was literally unbearable! Something like combining a rock chrusher and a jack hammer! Especially when you got it between two buildings. That's what I'm wondering about your Chinese diesel. Does it clatter like a Yanmar? We have to take this equipment to customers properties and some ain't going to like the noise.