What was found
(CAN) ENGINE LOG STATES STARTER CLUTCH WAS CHANGED AT AN UNDETERMINED TIME PRIOR TO THIS FAILURE. THE DOWEL ASSEMBLY THAT RETAINS THE STARTER CLUTCH ADAPTER APPEARS TO HAVE SHEARED. THIS CONDITION ALLOWED THE ADAPTER TO MOVE FREELY IN ITS BORE RESULTING IN GEAR MISALIGNMENT AND SUBSEQUENT PRESSURES THAT FAILED THE CRANKCASE. THE REASON FOR THE DOWEL FAILURE IS UNKNOWN, BUT POSSIBLE INCORRECT INSTALLATION OF THE STARTER CLUTCH ASSEMBLY (P/N 643231) CAUSED THE DOWEL TO FAIL.