As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A 100 HR INSPECTION, AN OIL LEAK WAS NOTED AROUND THE L/H FORWARD CRANKCASE AROUND THE UPPER CRANKCASE BOLT (PN 6-34A WITH PN LW-11866 NUT). THE ENGINE WAS CLEANED AND A DYE PENETRANT INSPECTION PERFORMED. A CRACK ROUGHLY 4 INCHES LONG WAS FOUND RUNNING VERTICALLY ON THE CRANKCASE FROM ABOUT 1 INCH BELOW THE CRANKCASE SEAM DOWN TO THE EDGE OF THE BEARING SURFACE OF THE BOLT HOLE, THEN DOWN ANOTHER 3 INCHES. THE ENGINE IS BEING REMOVED FOR REPAIR OF CRANKCASE (IF POSSIBLE) OR REPLACEMENT.