What was found
DURING CRUISE, FLT REPORTED HOT, ELEC SMELL IN COCKPIT & CABIN WITH RECIRC FANS OFF. WITH RECIRC FANS ON, SMELL GOES AWAY. DIVERTED TO ORD. *S/D* GROUND RUNUP REVEALED SLIGHT OIL SMELL IN COCKPIT & CABIN WHEN ISOLATED TO RIGHT PACK AND RIGHT ENG. NO ELEC OR PLASTIC SMELL DETECTED. OIL CONSUMPTION NORMAL. RT PRSOV LOCKED CLOSED & ACFT DISPATCHED TO SFO FOR ENG CHG. FOUND OIL IN LPC DRUM ROTOR, STUB SHAFT & FAN HUB. OIL CAN ENTER GASPATH THROUGH WEEP HOLES IN THE DRUM ROTOR & FAN SPINNER. THE ROOT CAUSE IS POOR SEALING OF 9TH STAGE AIR AT 1.5-2 BEARING CARBON SEAL ASSY 9TH STAGE AIR LEAKS TO THE NR 1 BEARING COMPT & UPSETS THE PRESS BALANCE ON NR 1 CARBON SEAL ALLOWING OIL TO LEAK TO LPC DRUM, SHAFT &