What was found
EN ROUTE TO OAK FOM YVR FLT 7525, PILOTS REPORTED HAVING A LOW TORQUE INDICATION ON NR 1 ENGINE. MAINTENANCE WAS ADVISED UPON ARRIVAL IN OAK. WHEN THE MECHANIC OPENED THE LOWER COWLING ON THE ENGINE A PIECE OF METAL THAT LOOKED LIKE A PIECE OF HOUSING FELL OUT. THE MECHANICS SENT DETAILED DRAWINGS BACK TO MAINTENANCE CONTROL AND ADVISED THAT THERE WAS A HOLE IN THE LOWER SECTION OF THE ENGINE THROUGH THE HOLE HE COULD SEE COMPRESSOR BLADES. ENGINE S/N 14100 HAS BEEN REMOVED AND REPLACED WITH ENGINE S/N 16014. ENGINE RUN, LEAKS CHECKS HAVE BEEN COMPLETED, OPS CHECK OK. TEST FLIGHT PERFORMED 1/18/99. AIRCRAFT RETURNED TO SERVICE. (M)