What was found
AFTER TAKEOFF, DURING CLIMB NR 1 ENGINE EXPERIENCED MULTIPLE STALLS. POWER WAS REDUCED, 160,000 POUNDS OF FUEL WERE DUMPED. AIRCRAFT RETURNED TO FIELD AND MADE A SAFE LANDING. ENGINE WAS VISUALLY AND BORESCOPE INSPECTED PER BOEING MM 72-00-00 PAGE 680Q WITH NO FAULTS FOUND. ON GROUND POWER RUN, ENGINE COMPRESSOR STALLED, ENGINE WAS GIVEN A COMPLETE BORESCOPE, TWO 3 INCH CONNECTING CRACKS WITH MISSING MATERIAL WERE FOUND ON THE AIR CLEANER ASSY UTILIZING THE B-3-1 PORT. AIRCRAFT FERRIED TO HKG WHERE THE NR 1 ENGINE WAS REPLACED. AIRCRAFT RETURNED TO SERVICE.