As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHEN THE LIFTER WAS REMOVED FOR BLEEDING AFTER A CYLINDER , IT WAS FOUND TO HAVE A SIGNIFICANT SIZE CHUNK MISSING FROM THE LIFTER FACE. THE ASSOCIATED CAM LOBE WAS INSPECTED AND FOUND TO BE IN SERVICEABLE CONDITION, THE LIFTER WAS REPLACED AND THE ENGINE RETURNED TO SERVICE.