What was found
FUME EVENT BEGAN SHORTLY AFTER TO. DIRTY SOCK ODOR UNTIL ABOUT FL200 THEN WAS MUCH BETTER. GOT STRONGER DURING DESCENT BELOW APPROX 10,000FT. AMM 21-00-21-2 JRH CH 6, & AMM 21-51-02-6, OPENED BOTH PACK BAY DOORS. INSPTED EXTERIOR OF ALL DUCTS AND PACK COMPONANTS FOR OIL CONTAMINATION, FOUND NONE. OPENED LT PACK HEAT EXCHANGER ACCESS DOOR. FOUND INSIDE OF HEAT EXCHGR CLEAN WITH NO OILY RESIDUE. CLOSED, ACCESS DOOR FOR HEAT EXCH. PERFORMED FUME CONTAM REMOVAL PROCEDURE IAW AMM 21-00-21-2. RAN BOTH PACKS, TURNED TEMP FULL HOT, COLD. DID NOT FIND ANY SMOKE OR ODOR OF FUMES. RAN ENGS, & CONTINUED PROCEDURE. DID NOT FIND ANY FUMES DURING CLEAN OUT PROCDURE, NOR ANY UNUSUAL FUMES IN COCKPIT.