Hope there are some Onan experts that read this. Have an 89 318 with Onan 18 hp at 951 hours. Oil dripping from the front of the engine. While changing the front gasket and seal noticed Welsh plug fell out in my hand and discovered the front camshaft bearing looks awful with pieces of it missing. Front crankshaft bearing looks great. Can the camshaft be removed without removing the valves? Would save a lot of cost of gaskets and time if I could just replace the cam bearings and welsh plug along with some other gaskets.