What was found
SHIP 3329 MUSTY SMELL THROUGHOUT AIRCRAFT ONCE T/O POWER SET ON T/O, DISSAPATED 20 MINS INTO FLIGHT FOG/MIST SEEN IN A/C ON T/O ROLL. CORRECTIVE ACTION: T/S APU INTERNALLY AND EXTERNALLY WITH ULTRA VIOLET LIGHT. REMOVED AND INSPECT APU BLEED AIR DUCT ELBOW. NO LEAKS FOUND. RE-INSTALLED APU ELBOW DUCT. LEAK CK OK. INSPECTED OVERHEAD LTS + BALLAST + PAX+ PSU LIGHTS, OUTLETS, IFE EQPT, GALLEY COMPONENTS. NO DISCREPANCIES AND SMELL NOTED. PERFORMED BOROSCOPE INSP #2 ENGINE HPC. STAGES 3-5 AS PER AMM 72-00. FOUND EVIDENCE OF OIL WETTING. REPLACED #2 ENGINE. PERFORMED #1 ENG HIGH POWER RUN. OPERATED BLEED SYS + PACK SYS. NO ODORS DETECTED.