What was found
AFTER TAKEOFF, NR 4 ENGINE FIRE WARNING ILLUMINATED WITH BELL AND NR 4 NACELLE TEMP AT 9. ACCOMPLISHED TROUBLESHOOTING PER FIM 36-11-00, FOUND PNEUMATIC PRESSURE RELIEF VALVE SPRING TENSION FAILED CAUSING VALVE TO STICK OPEN. REPLACED NR 4 ENGINE PNEUMATIC RELIEF VALVE IAW AMM 36-11-11. ACCOMPLISHED HIGH POWER ENG RUN SATISFACTORY. REPLACED NR 4 ENGINE HIGH PRESSURE SHUTOFF VALVE DUE TO SCHEDULING ERROR IAW AMM 36-11-06. OPS CHECKED, ENGINE RUN SATISFACTORY. REPLACED NR 4 ENGINE HIGH STAGE BLEED VALVE CONTROLLER FOR VALVE SCHEDULE ERROR IAW AMM 36-11-06. ENGINE OPERATIONS AND BLEEDS NORMAL DURING HIGH POWER ENGINE RUN-UP. ACFT OK FOR SERVICE.