What was found
DURING CRUISE, NR 2 ENGINE FIRE WARNING LIGHT AND BELL CAME ON INTERMITTENTLY AND THEN WOULD NOT TEST. NR 2 ENGINE SCAN REVEALED NO VISUAL CONFIRMATION OF FIRE. SHUTDOWN THE NR 2 ENGINE AND THEN FIRE WARNING TESTED OK. NR 2 ENGINE MAINTAINED 25 PSI OF OIL PRESSURE WHILE WINDMILLING. PERFORMED FIRE DETECTION SYSTEM LOOP GROUND CHECK ON THE NR 2 ENGINE IAW DC8 WDM, CHAPTER 26-11-1 AND SYSTEM CHECKED GOOD. PERFORMED GROUND OPS CHECK IAW DC8 MM, CHAPTER 26-10-1 AND SYSTEM CHECKED GOOD. GROUND RAN ENGINE TO TAKEOFF POWER AND NO DEFECTS OR WARNINGS WERE NOTED.