Doing lawn mower repair is sometimes easy to do but it may depend on the problem its experiencing. If you need to remove the camshaft or camgear, you need to read the following. First, you need to remove the camshaft driven plunger type oil pump, and inspect for damage. Next, you need to rotate the crankshaft carefully until the timing marks align which could be a line, dot, or hole on the crankshaft gear or camgear. Once the timing marks aligned, the valve pressure should be released on the camshaft. It doesn?t matter if you have removed the valves, and also it should slip out without difficulty. You have to inspect the camgear if there are chipped or broken teeth, and the cam lobes for wear or tear. There should be no damage on those. There should be no significant wear or damage on the valve lifters too. A replacement is necessary once a wear pattern is established.