What was found
DURING CRUISE FROM KLAX, NR 4 ENGINE FIRE WARNING ILLUMINATED. THE CREW PERFORMED COM EMERGENCY PROCEDURES, THE CREW DISCHARGED NUMBER ONE FIRE BOTTLE, AFTER TWO MINUTES FIRE WARNING ILLUMINATED AGAIN AND DISCHARGED NR 2 FIRE BOTTLE. THE CREW SHUT NR 4 ENGINE DOWN. THE CREW LANDED IN KICT WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED LEFT AND RIGHT FAN DETECTOR, LEFT AND RIGHT CORE, AND FIRE DETECTOR CONTROL UNIT. REPLACED BOTH FIRE BOTTLES. OPERATIONAL CHECK GOOD IAW MM 26-10-2, MM 26-11-16, 20-50-0, FCD 7-18-08, ERH 70.01, MM 26-11-07, AND GMM 3.124. AIRCRAFT WAS RETURNED TO SERVICE.