As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AN EXCESSIVE AMOUNT OF ALUMINUM WAS FOUND IN THE OIL SCREEN DURING A 50-HOUR INSPECTION. THE METAL WAS SENT TO LYCOMING FOR EVALUATION AND IT WAS DETERMINED TO BE FROM THE PISTON PIN PLUGS. ALL CYLINDERS WERE REMOVED AND ALL PLUGS SHOW EXCESSIVE WEAR TO VARYING DEGREES. SUBMITTER SUGGESTED POSSIBLE CAUSE AS A DEFECT IN THE METAL USED TO FABRICATE THE END PLUGS. (X)