What was found
BOS - FLT 786 - CLIMBING OUT FROM BOS ABOUT 8,000 FEET, THE NR 1 ENGINE OIL FILTER BYPASS LIGHT ILLUMINATED. CREW SHUT DOWN THE NR 1 ENGINE, DECLARED AND EMERGENCY AND RETURNED TO FIELD AT BOS. FLIGHT LANDED WITHOUT FURTHER INCIDENT. TOTAL SINGLE ENGINE TIME WAS 10 MINUTES. MAINTENANCE CHECKED THE NR 1 ENGINE OIL AND FILTER FOR CONTAMINATION. CHECKED GOOD. REMOVED AND REPLACED THE OIL FILTER BYPASS SWITCH AND CANNON PLUG. LEAK CHECK AND OPERATIONAL CHECK GOOD. (M)