What was found
DURING CRUISE, THE NR FOUR ENGINE FIRE WARNING LIGHT ILLUMINATED. THE ENGINE WAS SECURED AND THE FIRE BOTTLES WERE DISCHARGED. LIGHT REMAINED ON. FLIGHT REROUTED TO DEN. LANDED WITHOUT INCIDENT. FOUND LOWER FIRE LOOP LOOSE AND CONNECTOR FULL OF OIL. SECURED FIRE LOOP, CLEANED CONNECTOR, REPLACED FIRE BOTTLES AND SQUIBS. SYSTEM OPS CHECKED GOOD IAW DC-8 M.M., CHAPTER 26. OVERWEIGHT LANDING INSPECTION COMPLIED WITH IAW ABX CARD DC-8-3A. NO DISCREPANCIES NOTED.