What was found
DURING OIL CHANGE, REMOVED AND CUT OPEN OIL FILTER, FOUND COMPLETELY CONTAMINATED WITH NONFERROUS MATERIAL. APPEARED TO BE ALUMINUM. LYCOMING NOTIFIED, INFORMED OUR SHOP THAT MATERIAL PROBABLY WAS PISTON WRIST PIN OUTER BUSHINGS. AIRCRAFT GROUNDED, WAITING ON REPLACEMENT ENGINE. NOTE: CONDITION DID NOT DEGRADE-PREVIOUS OIL CHANGE (50 HRS) DID NOT SHOW MATERIAL OF ANY SORT. LYC SB 525 AND SB 527 A AND B ARE SIMILAR. (FACTORY REBUILT/OVERHAULED ENGINE.)