What was found
OPEN DIRTY SOCK ODOR OCCURRED INTERMITTENTLY AT CRUISE AND INTENSIFIED ON DESCENT. WE ACCOMPLISHED THE SMOKE AND FUME ELIMINATION CHECKLIST. EMERGENCY DECLARED. AMM 72-61-10-4, AMM 21-00-01-2, FOUND OIL AT FLIGHT IDLE ON LT ENG RUNNING FROM DRAIN MAST WHICH CONNECTS TO DE-OILER HOUSING. R & R ROTATING RING ASSY PACKINGS ON DE-OILER HOUSING. ALL OPS CHECKS ARE GOOD, RAN ENGINE UP TO TAKE OFF POWER. IAW MM 72-61-10-4, MM 21-00-01-2, AT ALL POWER SETTINGS, NO DIRTY SOCK ODOR NOTED