What was found
AFTER FINDING NR 6 CYLINDER CRACKED, REFERENCE SDR YAX15091403, WE INSPECTED ALL OTHER CYLINDERS & FOUND NR 4 CRACKED AS WELL. THE TELLTALE SIGN WAS BLUE FUEL STAINING BETWEEN THE 14TH & 15TH COOLING FINS ON THE TOP OF THE INTAKE PORT SIDE OF THE CYLINDER. THE CRACKS START THERE & THEN PROGRESS. SERVICE INSTRUCTION 1553 ADDRESSES THIS PROBLEM, BOTH BY ADVISING TECHNICIANS TO LOOK FOR CRACKING IN THE AREA & TO PREVENT THE PROBLEM FROM OCCURRING BY INSTALLING A FIN STABILIZER. HOWEVER, THOUGH THAT BULLETIN WAS RELEASED OVER 2 YEARS AGO, MFG DOES NOT SHIP SPARE CYLINDERS WITH THE STABILIZER INSTALLED. ALSO, HISTORICALLY THIS IS NOT A COMMON ISSUE. THE DAMAGED CYLINDERS HAVE BEEN SENT TO MFG & OUR INVESTIGATION IS ONGOING.