What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS OUT OF 14,000 FEET VERY STRONG ODOR " DIRTY SOCK SMELL "SMELL. MAINTENANCE ACCOMPLISHED JOB CARD 26L00021001, 26L00021002, 26L00021004, DURING 2100021001. FOUND APU SOURCE OF ODOR, DURING JOB CARD 26L00021002, FOUND APU OIL COOLING FAN AND TUBE TO BE LEAKING, REMOVED AND REPLACED OIL COOLING FAN AND TUBE IAW AMM 49-52-51. OPS AND LEAK CHECK GOOD, NO ODORS FOUND AT THIS TIME.