What was found
FUME EVENT DIRTY SOCK ODOR NOTICED BY ALL CREW ON AIRCRAFT. PACKS ON APU BLEED ODOR POSSIBLY STRONGER IN FWD CABIN, POSSIBLY PACK 1. FOLLOWED TSM 05-50-00-810-831-A. PER COSRS FOUND APU TYPE 1 AS PROBABLE CAUSE. CONFIRMED PRESENCE OF ENGINE OIL. PER TSM 49-00-00-810-921-A. INSPECTED APU & FOUND OIL LEAK ON APU ASSY, CLEANED & PERFORMED OPS CK IAW AMM 49-00-00. CONFIRMED OIL COMING FROM CENTER DRAIN LINE. PERFORMED ENGINE RUN & OPS CK OF PACK 1 & 2 PER AMM 71-00-00. NO DEFECTS NOTED. CONFIRMED NO PRESENCE OF OIL AT THIS TIME.