As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: STRONG OIL ODOR WITH APU BLEED ON. PERFORMED JC'S 26L00021001 AND 26L00021002. FOUND APU TO BE SOURCE OF ODOR. FURTHER T/S IAW TSM 49-00-81-810-874-A. APU COMP. HAS NO EVIDENCE OF LEAKS. FOUND AFT HYD. SEAL DRAIN COLLECTOR TANK OVERFLOWING AND LEAKING OVER KEEL BEAM AND UP THE BELLY TO APU. DRAINED TANK IAW AMM 29-17-00 AND RAN EACH CONTRIBUTING SYST. WITH NO LEAKS FOUND.