What was found
CLE - FLT 691 - APPROX 50 MILES OUT FROM CLE, THE NR 1 ENGINE OIL FILTER BYPASS LIGHT ILLUMINATED. CAPTAIN WENT THROUGH PROCEDURES, THEN SHUT DOWN THE NR 1 ENGINE IN FLIGHT. AN EMERGENCY WAS DECLARED. FLIGHT LANDED WITHOUT INCIDENT AT CLE. TOTAL SINGLE TIME WAS 12 MINUTES. MAINTENANCE REMOVED AND REPLACED THE NR 1 ENGINE MAIN OIL FILTER. INSPECTED REMOVED FILTER AND FOUND NO CONTAMINANTS. REMOVED AND REPLACED THE NR 1 ENGINE OIL FILTER BYPASS SWITCH. RAN ENGINE. LEAK CHECK GOOD. OPS CHECK GOOD. (M)