O-ring 753-05902

Remove the clutch cover. Then remove the spark plug and insert a length of rope into the cylinder, leaving a few inches out. Then pull on the starter rope until the piston comes in contact with the rope and stops the engine from turning. Then using a torx T-20 (As I remember it might be a T-25) remove the clutch drum. Then with safety glasses on, strike an edge of the clutch with a hammer and screwdriver until it is loose, once usually does it. Then remove the old starter housing assembly by removing the screws that secure it. An install the new one. Replace the clutch assembly and clutch cover in reverse order of tear down. Remove the rope from the cylinder, and install the new spark plug gapped at 0.025 I also replaced the o-ring between the cylinder and rocker cover.