What was found
WHILE PERFORMING ANNUAL INSP, ALUMINUM SHAVINGS WERE FOUND IN THE OIL FILTER. FILTER SENT TO LYC FOR ANALYSIS AND DETERMINED TO BE PISTON PIN PLUG MATERIAL. UPON REMOVAL OF ALL 4 CYLINDERS, SEVERE PITTING FOUND AT BOTTOM OF EACH CYL WALL AT THE POINT WHERE PISTON TOUCHES ITS LOWEST TRAVEL. ALL 4 CYL''S REJECTED AND FACTORY NEW INSTALLED. FACTORY STATES THIS IS RESULT OF ENG NOT REACHING PROPER OPERATING TEMP. ACFT IS OPERATED IN PHOENIZ, AZ, OIL TEMP GAUGE IS ACCURATE.