As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED A LAVATORY SMOKE WARNING, ACCOMPANIED BY THE ODOR OF SMOKE. THE F/A ALSO REPORTED SMOKE AND ODOR. THE ACFT RETURNED TO DEPARTURE AND LANDED WITHOUT INCIDENT. MX INSPECTED AND REPLACED THE NR 2 ENGINE. OPS CHECKED GOOD. CAUSE OF SMOKE WAS OIL LEAKING UNDER NR 4 SEAL RUNNER. SB 72-401 INSTALLS A NEW DESIGN SPACER AND HIGER TEMP SEALS.