Stuff happens with all engines. From Mark's description of the wear on the cam gear, it sounds as if either the cam or crank gear was just a little bit eccentric which was bound to cause a failure. With no PMA process in place for something like a Corvair or VW engine, how do you make sure that you are getting quality parts? Are you engine builders checking your gear runout with a dial indicator? I probably would not have. It sounds as if there may be a batch of either cam or crank gears that are not quite true.
FWIW, I have my O-200 apart for some maintenance right now as well. When I built this engine, I let my machinist talk me out of replacing the exhaust valve guides. I'll mark that up to his and my learning curve with these engines. The consequence of failing to replace 4 $5.00 guides and leaving in guides that were worn beyond spec was an engine that tends to push oil out the blow by and drool oil onto the ramp. I've had this tear down scheduled for some time as routine maintenance during this year's annual inspection. When I pulled the valve cover off #3 cylinder, something fell out of the valve cover and thumped into the drain pan. I found that sometime in the last 350 hours, an outside rocker shaft boss had broken off and was laying inside the valve cover. Fortunately, the center boss is pretty beefy and held the rocker shaft in place so the failure didn't impact the engine performance. This is the type of engine problem I love to find. The broken part failed to impact the engine performance and was found with the plane parked safely in the hangar. :o) I do expect this engine to be apart for the next month as this cylinder will have to be sent out for repair. Jeff Scott Los Alamos, NM _____________________________________________________________ Smart Vacation. Stay Longer, Pay Less! Click Here. http://thirdpartyoffers.juno.com/TGL2121/fc/Ioyw6i3nJgyLAKT2DZNfdduwndZCjeiH0DHo6UMXcvf1e45NyETnAc/?count=1234567890
