As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING ROUTINE CPC NR 2 INSPECTION, THE ACFT OIL FILTER WAS OPENED TO CHECK FOR CONTAMINATION AND ALUMINUM WAS FOUND IN THE FILTER ELEMENT. WE PROCEEDED TO REMOVE ENGINE CYLINDERS AND FOUND NR 1 CYLINDER PISTON PIN PLUG WORN, FURTHER INSPECTION OF CYLINDER WAS CARRIED OUT AND A GROOVE WAS FOUND NEAR THE BASE OF THE CYLINDER CAUSING THE PISTON PIN PLUG TO WEAR.