Replacement Cam Shaft made from toughened metal for prolonged life.
Generator Guru says:
Rarely needs replacing. To diagnose a failed Cam Shaft you will have one of the following symptoms:
1) Valves opening at the wrong time leading to a misfire of the engine, and excess carbon build-up in the cylinder head even after rockers have been set correctly. (If you need the Valve settings please see "Cylinder Head Parts" as the settings are listed here for each unit.)
2) Bent push rods. This can be an early indication. If you replace the push rods and they bend again then it is almost certain your Cam Shaft has failed.