As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING INSPECTION OF THE OIL FILTER IT WAS NOTICED THAT THERE WAS A SMALL AMOUNT OF METAL. MEASURED VALVE CLEARANCES AN NR 4 EXHAUST WAS OUT OF TOLERANCE. THE CYLINDER WAS PULLED AND THE CAM HAD SIGNIFICANT WEAR. ENGINE WAS REMOVED AND SENT FOR REPAIR.