What was found
(CAN) ENGINE WAS REMOVED FROM THE AIRCRAFT AND SENT TO AN OVERHAUL FACILITY FOR AN INSPECTION DUE TO A PROP STRIKE. DURING THE INSPECTION OF THE CRANKSHAFT, IT WAS NOTICED THAT THE URETHANE INTERNAL COATING (PID) WAS BLISTERING. FURTHER INSPECTION OF THE AREA REVEALED CORROSION, WHICH WAS BEYOND LIMITS, AND THE CRANKSHAFT WAS TAKEN OUT OF SERVICE. THE ENGINE WAS A FACTORY EXCHANGE WITH 4 YEARS AND 776.0-HRS ON IT. THE CRANKSHAFT WAS MARKED PID AND DID NOT REQUIRE ANY INTERNAL INSPECTIONS UNTIL OVERHAUL AT 2000-HRS (REF AD 98-02- 08, SB 530B, SB 505B).