What was found
(CAN) AFTER LANDING AND GOING TO REVERSE PITCH, PILOT REPORTED SMOKE COMING FROM ENGINE. SHORTLY AFTER LANDING, THERE WAS SMOKE ALSO IN COCKPIT. PILOT DECLARED EMERGENCY. AFTER INVESTIGATION, FOUND MAJOR OIL LEAK COMING FROM A CAPPED TRANSFER TUBE PORT ON THE L/H TOP SIDE OF THE REDUCTION GEARBOX. NOTE : ON THE TWO BOLTS HOLDING THE CAP IS ATTACHED TWO CLAMPS WHICH HOLD THE STICK PUSHER TORQUE TRANSDUCER. THE UPPER BOLT OF THE CAP HAS BEEN FOUND PROTRUDING FROM THE RGB FLANGE. THE LOWER BOLT WAS IN CORRECT POSITION. (SEE ATTACHED PICTURE) WHILE REMOVING THE BOLTS, THE HELICOIL INSERTS CAME OUT FROM THE RGB CASTING. BOTH HELICOILS WERE BROKEN AND BOTH BOLTS WERE STRIPPED FOR 1/4 OF THEIR THREADS.