As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN CLIMB EXPERIENCED HEAVY BURNING SMELL IN ACFT. TURNED OFF RT PACK. SMELL RETURNED WHEN WAITING FOR A GATE ON THE GROUND. FOUND OIL LEAKING ON INLET SIDE OF APU DUCT. PLACARDED APU INOP. LATER CLEANED APU COMPT AND SURROUNDING AREA. RAN APU FOR 2 HOURS AND NO LEAKS OR ODOR. POSSIBLE SERVICING PROBLEM. CHECK-C 8-2-98 STL.