What was found
DUE TO POOR PERFORMANCE, HIGH MAGNETO DROP, ACFT WAS SENT, WO 22830 DATED 04 AUGUST 2016 FOR INSPECTION, TROUBLESHOOTING. VISUAL INSPECTION FOUND ABNORMAL WEAR OF CYLINDER, NR 1 AND NR 2 ROCKER ARMS AND PUSHROD ENDS AT MATING SURFACE. APPEARS TO BE OIL STARVATION, CHATTERING, CREATING EXCESSIVE VALVE LASH CLEARANCE AND WEAR. ENGINE TIME SINCE MAJOR O/H, 273.0 HRS. OIL USED, XC20W50, AT TIME OF DISCOVERING DEFECTIVE ENGINE PART HAD 40 HOURS SINCE LAST OIL CHANGE AND OIL ANALYSIS TEST WITH NO ABNORMALITIES.