What was found
DURING CLIMB, FIRE WARNING INDICATION OCCURRED ON THE NR 4 ENGINE. DISCHARGED BOTH FIRE EXTINGUISHERS, BUT FIRE WARNING INDICATION REMAINED. COMPLETED INFLIGHT SHUTDOWN OF THE NR 4 ENGINE. REPLACED LOWER FIRE LOOP ASSEMBLY AND UPPER AFT FIRE LOOP ASSEMBLY ON THE NR 4 ENGINE. REPLACED BOTH FIRE EXTINGUISHERS ON THE RIGHT WING. COMPLETED PNEUMATIC LEAK CHECK OF THE NR 4 ENGINE AND NO LEAKS WERE NOTED. NO INDICATIONS OF A FIRE ON THE NR 4 ENGINE WERE NOTED.