What was found
BWI - FLT 1243 - FLIGHT HAD JUST LEVELED OFF AT 28,000 FEET WHEN CREW NOTICED THE NR 1 ENGINE OIL QUANTITY BEGAN TO DECREASE TOWARDS ZERO. FLIGHT DIVERTED TO BWI AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED AND NO ENGINE SHUT-DOWN OCCURRED IN-FLIGHT. MAINTENANCE FOUND THE NR 1 ENGINE STARTER GARLOCK SEAL LEAKING. REPLACED SAME ALONG WITH STARTER SHAFT SEAL HOUSING ASSEMBLY. PULLED NR 1 ENGINE OIL SCREEN AND CHECKED FOR CONTAMINATION. NONE FOUND. REPLACED FILTER ASSEMBLY. SERVICED OIL AND GROUND RAN THE NR 1 ENGINE. ENGINE RUN AND LEAK CHECK GOOD. (X)