What was found
(CAN) THE PILOT REPORTED A RT ENGINE OIL PRESSURE FLUCTUATION IN FLIGHT AND AN OIL PRESSURE DECREASE UP TO 40 PSI WHEN THE LOW OIL PRESSURE ALARM LIGHT ON. PILOT ELECTED TO SHUTDOWN THE RT ENGINE. THE ON GROUND INVESTIGATION EVEALED OIL STAINS ON THE ENGINE COWLING AND A TRACE OF OIL LEAKAGE TO THE FUEL PUMP DRIVE SHAFT SEAL. THE SEAL AND AN OIL HOSE WERE REPLACED. THE LEAK CHECK WAS PERFORMED AND IT WAS SATISFACTORY.