As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) NR 1, NR 2 AND NR 4 CYLINDER PISTONS CRACKED BETWEEN OIL HOLES. THEPISTONS ARE MANUFACTURED BY WELLWORTH CASTING NUMBER A470102 AND ARE DIFFERENT TO THE CONTINENTAL MANUFACTURED PISTON IN HAVINGTEN OIL HOLES UNDER THE OIL RING WHERE CONTINENTAL PISTONS HAVE EIGHT HOLES BELOW THE OIL RING. LOG BOOK INDICATES THAT NO3 PISTON WAS PREVIOUSLY CRACKED AND HAD BEEN REPLACE BY A CONTINENTAL PNO 530348.