What was found
FLIGHT ATTENDANT REPORTED A BURNING SMELL DURING TAXI OUT IN REAR OF ACFT. FLIGHT RETURNED TO THE GATE. ACCOMPLISHED JOB CARD 26L00021001, TROUBLESHOOT CABIN AIR QUALITY. CHECKED ENG, PACK INLETS & APU INLETS. NO PROBLEMS FOUND. FOUND APU SERVICED PAST 1LT MARK. REMOVED EXCESS OIL. CHECKED AFT GALLEY CHILLER & COFFEE MAKERS, NO PROBLEM FOUND. FOUND AFT GALLEY AIR EXHAUST FILTERS CLOGGED. REPLACED FILTERS, RAN APU BLEED & PACKS. NO SMELL RETURNED. RAN ENG, NO SMELL FOUND. OK FOR SERVICE.