What was found
CRACKED CYLINDER INSTALLED. THE ENGINE HAS APPROXIMATELY 850 HOURS ON IT SINCE OVERHAUL. DURING OVERHAUL, SIX NEW CYLINDERS WERE INSTALLED. THE ACFT RECENTLY CAME IN FOR A 50 HOUR INSPECTION AT WHICH TIME A COMPRESSION TEST WAS CONDUCTED. DURING THE COMPRESSION TEST CYLINDER NR 5 WAS NOTED TO BE LEAKING AIR FROM BETWEEN THE FINS IN THE AREA OF THE INTAKE VALVE. THE CYLINDER WAS REMOVED AND A CRACK WAS OBSERVED EMANATING FROM THE UPPER SPARK PLUG HOLE TO THE INTAKE VALVE SEAT. CYLINDER DATE OF MANUFACTURE MAY 17 2010. REFERENCE AIRMOTIVE ENGINEERING CORP 8130-3 TRACKING NR 10051710979-1-1. THE S/N OF THIS CYLINDER IS OUTSIDE THE RANGE OF APPLICABILITY AS OUTLINED IN THE AD. HOWEVER SINCE IT HAS HAD A SIMILAR FAILURE AS THOSE DESCRIBED IN THE AD, WANTED TO BRING IT TO YOUR ATTENTION, IN THE EVENT THAT WIDENING THE S/N APPLICABILITY RANGE MIGHT BE NECESSARY.