As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ROUTINE OIL CHANGE, METAL WAS FOUND IN FILTER. ENGINE WAS REMOVED AND DISASSEMBLED. CAUSE WAS FOUND TO BE LIFTER FACE AND CAM LOBE SPALLING ON CYLINDER CAM LOBES NR5 AND NR6 INTAKE. NO CORROSION NOTED. TWO OTHER INTAKE LIFTERS EXHIBIT PREMATURE WEAR, REMAINING CAM LOBES CHECK. OKAY FOR WEAR. CAMSHAFT WAS INSTALLED.