I have a 3 year old Craftsman T210 with the Kohler 5400 series engine - 18HP 541CC. Here's the high level:
It is running ROUGH (sputters, not much power particularly when the blades are engaged)
hard to turn over - even replaced the battery, which helped a little, but turns a lot before it engages
can't have the throttle all the way up to "rabbit" setting (it chokes up at that level vs revving high like when it was new), I have to leave it about 2/3 up
replaced the oil, oil filter, and the air filter - no improvement
A few folks have suggested it might be the carb? Is this something I can easily fix/replace myself..? (I have tools, but this would be new for me).