Yeah, I didn't know anything about this until it went up. But apparently around 1,000 hours. The plastic camshaft gears on these 22 horsepower Kawasaki engines fail. Looking into it, it's not that hard to repair. But I need to get it apart to see if it been any of the push rods or not before I order the parts. Probably pull the heads off of it and look at the cylinder bores as well.