I've had a PB-255LN as well for four years now. Did have the flywheel nut come loose a year and a half ago.
Other than that, it starts rite up on the first or second pull. If I remember to use the choke. :rolleyes:
Hey. Yagotta take care of the outside as well as the inside, (oil changes, etc..). Just put a coat of AutoGlym High Definition Wax on my Craftsman rider mower this week. Also changed the oil and hit the zerks with an annual supply of grease. :)