What was found
(CAN) FUEL CONTROL P/N 1-170-240-93, S/N 5ADS1907 WAS RECEIVED DUE TO DAMAGED MAIN DRIVE SHAFT SPLINE. DISASSEMBLED AND INSPECTED FCU AND FOUND DAMAGED PUMP ASSEMBLY. RECORD OF INSPECTION IAW SB73-39. FCU S 91 AND 93 HAVE TIP SEAL PUMP, AND THEY CAN BE INSTALLED ON FOLLOWING ENGINE TYPES: T5313B, T5317A, T5317A-1 AND T5317B. INVESTIGATED TWO TIP SEAL PUMP AND MAIN DRIVESHAFT FAILURE ON FCU FITTED WITH TIP SEAL PUMPS. FAILURE OF THESE PARTS LEADS TO LOSS OF FUEL SUPPLY TO FCU, BOTH AUTOMATIC AND EMERGENCY SUPPLY, CAUSING ENGINE FLAMEOUT. IN BOTH CASES THE FCU S INVESTIGATED HAD TSO IN THE MID LIFE RANGE. WAITING FOR FURTHER CLARIFICATION AND GUIDANCE FROM THE MFG.