What was found
DURING CRUISE, NR 4 ENGINE GENERATOR UNPARALLEL LIGHT FOLLOWED BY GENERATOR DRIVE OIL LIGHT, MANIFOLD PRESSURE LIGHT ILLUMINATED WITH HIGH PRESSURE MANIFOLD AIR PRESSURE OVERTEMP LIGHT CAME ON, LOSS OF EGT INDICATION, ZERO FUEL FLOW AND ZERO EPR. THE CREW SHUTDOWN NR 4 ENG AND RETURNED TO DEPARTURE WITHOUT FURTHER INCIDENT. MAINTENANCE INSPECTED ENGINE AND FOUND ELBOW DUCT ON PNEUMATIC PRESSURE REGULATOR DISCONNECTED AND NUMEROUS WIRES DAMAGED. THEY RECONNECTED ELBOW DUCT AND REPAIRED DAMAGED WIRES. OPERATIONAL CHECK GOOD IAW DC8 MAINTENANCE MANUAL 36-11-11, BOEING SWPM 20-10-01, 20-10-03, WD 24-2-4, 28-5-0 AND 72-2-0. AIRCRAFT WAS RETURNED TO SERVICE.