What was found
DIRTY SOCK ODOR THROUGHOUT AIRCRAFT. ODOR ISOLATED TO APU. PEFORMED DECONTAMINATION OF THE (ECS) IAW AMM 21-00-00-615-004-A. R & R DEOILER CASING SEAL ASSY AT ENG #1 IAW AMM 72-60-31. NO LEAKS. REMOVED & REPLACED APU COOLING FAN IAW AMM 49-52-51 & APU OIL COOLER IAW AMM 49-91-44, OPS & LEAK CHECKED OK, NO DIRTY SOCK ODOR. CLEANED APU AREA & DUCTS IAW STANDARD PRACTICES & PROCEDURES & EC A4917122-01, RAN APU & BLEED FOR SEVERAL HOURS, NO DIRTY SOCK ODOR NOTED. RAN EACH ENGINE FOR SEVERAL MINUTES, NO ODORS NOTED. AIRCRAFT IS OK FOR SERVICE.