What was found
ABNORMAL VIBRATION FELT THROUGHOUT THE AIRCRAFT DURING ALL PHASES OF FLIGHT. VIBRATION WAS WORSE WITH PROPS AT MAX & HIGHER TORQUE SETTINGS. UPON LANDING, NR 2 ENGINE NACELLE & PROP COATED IN FLUID. ALL ENGINE INSTRUMENT INDICATING GREEN, NO ASSOCIATED CAUTION OR WARNING LIGHTS. MX REPLACED NR 2 PROPELLER ASSY. FURTHER INSPECTION OF PROP ASSY REVEALED THE INNER BEARING RACE ON THE NR 4 BLADE HAD DISINTEGRATED, BALL BEARINGS HAD DISLODGED FROM THE BEARING SEPARATOR AND THERE WAS SIGNIFICANT DAMAGE TO THE NR 4 BLADE ROOT & HUB. THE OUTER BEARING RACE MOVE INWARD OFF IT'S SEAT AND THE OIL SEAL HAD SLIGHTLY DISLODGED OUTWARD ALLOWING OIL LEAKAGE.