As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER NR 1 ENG START LOUD HARMONIC VIBRATION NOISE UNDER FLT DECK FLOOR, STARTED ENGINE 1 & OBSERVED LOW HARMONIC HUM OR BUZZ. STARTED ENGINE 2 BUZZ REMAINED. DESELECTED ENGINE 1 HYD PUMP & THEN ENGAGED PUMP AGAIN. NO FLUCTUATIONS OBSERVED IN GREEN SYS QTY OR PRESSURE. PRESSURE REMAINED ABOVE 3000 PSI. RAN BOTH ENGINES FOR 15 MINS. UPON SHUTDOWN OF BOTH ENG 1 & 2, NOTICED OIL ODOR. R & R NOSE STEERING CONTROL MODULE IAW AMM 32-51-51. OPS CHKD IAW 32-51-00, CHKD GOOD.