KAISERAIR, INC.

AN OIL LEAK WAS FOUND ON THE ENGINE LUBRICATION UNIT WHERE THE AFT SUMP OIL SCAVENGE TUBE CONNECTS TO THE LUBRICATION UNIT. THE OIL SCAVENGE TUBE WAS REMOVED AND A NEW GASKET WAS INSTALLED. THE FOUR ATTACHING BOLTS WERE INSTALLED AND TORQUED PER THE AMM, USING A CALIBRATED TORQUE WRENCH. THE ENGINE RUN WAS ACCOMPLISHED WITH NO OIL LEAKS NOTED. A FLIGHT WAS INITIATED AND WHILE IN FLIGHT THE SCAVENGE OIL LINE LEAKED AT THE LUBRICATION UNIT, REQUIRING AN INFLIGHT SHUTDOWN OF THE ENGINE. MAINTENANCE REMOVED THE OIL LINE FROM THE LUBRICATION UNIT. INSPECTION FOUND THE THREADED INSERTS IN THE FOUR ATTACHING HOLES OF THE LUBRICATION UNIT HAD BACKED OUT AND WERE PROTRUDING ABOVE THE SURFACE OF THE LUBRICATION UNIT. THIS CONDITION PREVENTED THE GASKET FROM SEALING BETWEEN THE UNIT AND OIL LINE. THE LUBRICATION UNIT WAS SUBSEQUENTLY REPLACED WITH NO FURTHER LEAKS. THE THREADED INSERTS IN THE LUBRICATION UNIT SHOULD BE INSPECTED TO MAKE SURE THEY ARE SECURE, INSTALLED CORRECTLY AND NOT PROTRUDING ABOVE THE MATING SURFACE WHEN OIL LINES ARE ATTACHED TO THE LUBRICATION UNIT.

AIRCRAFT SLOWLY LOST PRESSURIZATION AT 300 FPM DURING CRUISE FLIGHT. TROUBLESHOT THE PROBLEM USING THE BOEING 737 FIM. DETERMINED TO BE LOW AIR DUCT PRESSURE COMING FROM THE RIGHT ENGINE. USING STEPS LISTED IN THE FIM TO TEST VALVES ON THE RIGHT ENGINE, DETERMINED THE RIGHT PRESSURE REGULATING AND SHUTOFF VALVE NEEDED TO BE CHANGED. CHANGED THE VALVE AND PERFORMED ENGINE RUNS. RIGHT ENGINE AIR DUCT PRESSURE WAS NOW CORRECT.

IN CRUISE FLIGHT THE LEFT ENGINE SURGED REPEATEDLY. THE ENGINE STOPPED SURGING WHEN AT FLIGHT IDLE. AIRCRAFT LANDED WITH THE LEFT ENGINE AT IDLE POWER.

CORROSION FOUND ON THE AFT LAVATORY INBOARD SUPPORT FITTING. STATION 947, LBL 25, WL208.

CORROSION FOUND ON THE L1 DOOR LOWER SILL WEB (MOP SILL) AND C CHANNEL.

CORROSION FOUND ON THE UPPER SURFACE OF THE UPPER CHORD OF THE FLOORBOARD FLOOR SUPPORT @STATION 360, RBL 5 TO RBL 66.

CORROSION FOUND ON THE UPPER SURFACE OF THE UPPER CHORD OF THE FLOORBOARD FLOOR SUPPORT @ STATION 312, RBL 8, WL208.

CORROSION FOUND ON THE L2 DOOR LOWER SILL INNER CHORD (MOP SILL) AND WEB.

CORROSION FOUND ON THE UPPER SURFACE OF THE UPPER CHORD OF THE FLOORBOARD FLOOR SUPPORT @ STATION 344, LBL 66 TO RBL 10.

CORROSION FOUND ON THE UPPER SURFACE OF THE UPPER CHORD OF THE FLOORBOARD FLOOR SUPPORT @STATION 986.5, LBL 25 TO RBL 24.

CORROSION FOUND ON THE FORWARD CARGO SIDE PLATE (Z CHANNEL) AT RBL 21.8 BETWEEN BS 482 AND BS 482A.

CORROSION FOUND ON THE UPPER SURFACE OF THE LEFT AND RIGHT WINGS ALONG STRINGER HI-LOK ROWS. LEFT WING LOCATION STRINGERS S-11 AND S-12 FROM APPROX WBL 183.4 TO WSTA 479. RIGHT WING LOCATION STRINGERS S-10, S-11 AND S-12 FROM APPROX WBL 70.85 TO WSTA 505.00. BOEING ENGINEERING CONTACTED FOR REPAIRS.

ENGINE BLEED AIR 5TH STAGE CHECK VALVES ON BOTH ENGINES INSPECTED FOR EMERGENCY AD 2020-16-51. BOTH CHECK VALVES SHOW SIGNS OF CORRODED FLAPPER PLATES, BUSHINGS AND WILL BE REPLACED.

THE WING FUEL TANKS BECAME IMBALANCED BY 800 LBS. AFTER THE CENTER FUEL TANK WAS EMPTIED. THE FUEL CROSSFEED VALVE WAS DETERMINED TO BE LEAKING. REPLACED THE FUEL CROSSFEED VALVE WITH NO FURTHER INDICATIONS OF FUEL LEAKAGE.

THE ELEVATOR TRIM WHEEL INDICATION GUIDE PIN CAME OUT OF THE GROOVE ON THE ELEVATOR TRIM WHEEL. THE GUIDE PIN JUMPED FORWARD TO ANOTHER GROOVE BECAUSE IT IS SPRING LOADED FORWARD. THE TRIM INDICATOR IS RELIED ON TO BE ACCURATE TO DETERMINE TAKE OFF CONFIGURATION. THE PILOTS SET THE ELEVATOR TRIM INDICATOR IN THE TAKE OFF BAND AND PROCEEDED TO TAKE OFF WITH THE ELEVATOR TRIM TABS BEING ALMOST FULL NOSE UP. THE ELEVATOR TRIM WHEEL ATTACHING SCREWS WERE FOUND TIGHT. THE GUIDE PIN ARM WAS FOUND SLIGHTLY BENT WHICH MAY HAVE CONTRIBUTED TO THE PIN JUMPING OUT OF THE GROOVE ON THE WHEEL. THE GUIDE PIN WAS PLACED BACK IN THE CORRECT GROOVE WITH POSITIVE ENGAGEMENT AND THE ELEVATOR TRIM SYSTEM WAS CHECKED FOR CORRECT RIGGING.

CORROSION FOUND ON THE BOTTOM FRAME ON THE LEFT OVERWING ESCAPE HATCH. MATERIAL THICKNESS REMAINING AFTER CORROSION REMOVAL FROM THE DOOR NOT WITHIN THE LIMITS OF SRM 52-20-02. REPLACED THE LEFT OVERWING ESCAPE HATCH.

CORROSION FOUND ON THE BOTTOM FRAME ON THE RIGHT OVERWING ESCAPE HATCH. MATERIAL THICKNESS REMAINING AFTER CORROSION REMOVAL FROM THE DOOR NOT WITHIN THE LIMITS OF SRM 52-20-02. REPLACED THE RIGHT OVERWING ESCAPE HATCH.

THE LEFT AIR CONDITIONING BLEED AIR VALVE CIRCUIT BREAKER IS POPPING. FOUND THE 3 O'CLOCK STRUT WIRE HARNESS THAT CONNECTS TO THE BLEED AIR VALVE SHORTED. REPLACED THE WIRE HARNESS AND OPERATIONAL CHECK NORMAL.

10EA VARIABLE STATOR VANE SECOND STAGE ACTUATOR BUSHINGS FOUND MISSING OR BROKEN ON ENGINE. ENGINE REMOVED AND SENT TO SHOP.

LEFT CENTER TANK FUEL PUMP LOW PRESSURE ANNUNCIATOR CAME ON BRIEFLY WITH THE FUEL LEVEL IN THE CENTER TANK OVER HALF FULL. REPLACED THE LEFT CENTER TANK FUEL OVERRIDE PUMP MOTOR IMPELLER. OPERATIONAL CHECK NORMAL.

FLANGED BUSHINGS WERE FOUND LOOSE OR MISSING FROM THE STAGE 2 UNISON RING ON THE NR 2 ENGINE. THE STAGE 2 UNISON RING WAS REPAIRED BY REPLACING 18 EA FLANGED BUSHINGS.

APU INTERMITTENTLY DOES NOT START ON BATTERY POWER. PERFORMED AN APU BITE CHECK FOR CURRENT FAULTS. FOUND MAINTENANCE MESSAGE 49-41248. TROUBLESHOT THE SYSTEM DOWN TO THE START CONVERTER UNIT USING THE FAULT ISOLATION MANUAL. REPLACED THE START CONVERTER AND OPERATIONAL CHECK NORMAL.

ENGINE WOULD AUTO SHUTDOWN WHEN POWER LEVER WAS ADVANCED PAST IDLE. VSV UNISON RINGS AND LEVER ARMS WERE INSPECTED. MULTIPLE LEVER ARMS WERE FOUND DISCONNECTED FROM THE STAGE 2 UNISON RING AS WELL AS SOME ARMS WERE BROKEN. SUSPECT UNISON RING BROKE AND REPOSITIONED ITSELF TO DISENGAGE SOME VSV ARMS AS WELL AS BREAKING SOME VSV ARMS. ENGINE WILL HAVE TO BE REMOVED AND SENT TO SHOP FOR REPAIR.

RIGHT ENGINE START VALVE WOULD NOT OPEN FAR ENOUGH TO ALLOW FOR ENGINE START. REPLACED START VALVE AND OPERATIONAL CHECK NORMAL.

APU GENERATOR WOULD NOT COME ONLINE WHEN SELECTED ON AFTER APU START. REPLACED APU GENERATOR AND OPERATIONAL CHECKED NORMAL.

LEFT CENTER FUEL TANK BOOST PUMP LOW PRESSURE LIGHT CAME ON. RESET SWITCH AND WORKED INTERMITTENTLY. REPLACED LEFT CENTER FUEL TANK BOOST PUMP AND OPERATIONAL CHECK NORMAL.

INTERMITTENT LEFT DUCT OVERHEAT LIGHT ON WITH NORMAL DUCT TEMPERATURE INDICATION. DETERMINED TO BE AN INDICATION PROBLEM. REPLACED THE 190 DEGREE AND 250 DEGREE SWITCHES IN THE AIR CONDITIONING DUCT/PLENUM. OPERATIONAL CHECK NORMAL.

APU SHUTDOWN AFTER AN HOUR OF RUN TIME ON THE GROUND. PUT A PRESSURE GAUGE IN THE FUEL LINE BETWEEN THE FUEL CONTROL AND FUEL ATOMIZER. FOUND FUEL PRESSURE AT 25 PSI WITH A REQUIREMENT FOR 50-60 PSI. REMOVED FUEL CONTROL UNIT AND FOUND DRIVE SHAFT SHEARED. REPLACED THE FUEL CONTROL UNIT AND OPERATIONAL CHECK NORMAL.

DUCT PNEUMATIC PRESSURE DURING CRUISE WAS 40 PSI BUT VERY LOW FLOW IN CABIN. FOUND LEFT 35 DEG SENSOR FAULTY. REPLACED THE SENSOR AND OPS CHECKED OK.

APU DRAGS DOWN DURING MAIN ENGINE START. REPLACED APU PROPORTIONAL CONTROL VALVE. ENGINE START AND APU OPERATIONAL CHECKS NORMAL.

UNSTABLE CABIN PRESSURIZATION. PERFORMED FUNCTIONAL CHECK OF CABIN PRESSURIZATION CONTROLLER WITH NO FAULTS FOUND. FOUND RESIDUAL PRESSURE IN THE BLEED AIR MANIFOLD WITH APU NOT RUNNING. REPLACED THE APU LOAD CONTROL VALVE.

START VALVE ON RIGHT ENGINE WAS INTERMITTENT OR SLOW TO OPEN WHEN START WAS INITIATED. REPLACED START VALVE AND OPERATIONAL CHECK NORMAL.

DURING AIR CONDITIONING PACK OPERATION ON THE GROUND, LEFT AIR CONDITIONING PACK INDICATED A PACK TRIP AND DUCT OVERHEAT AT PACK START UP. INDICATION FOR THE DUCT TEMPERATURE DID NOT SHOW A DUCT OVERHEAT. DETERMINED THIS TO BE AN INDICATION PROBLEM USING THE FIM. REPLACED THE AIR CONDITIONING ACCESSORY UNIT AND OPERATIONAL CHECK WAS NORMAL.

BITE CHECK OF THE CABIN TEMPERATURE CONTROLLER INDICATED AN INTERNAL FAILURE OF THE CONTROLLER. REPLACED THE CABIN TEMPERATURE CONTROLLER AND OPERATIONAL CHECK NORMAL.

ON GROUND, PACKS DO NOT DELIVER COLD AIR DISCREPANCY WAS WRITTEN BY FLIGHT CREW. TROUBLESHOOTING DETERMINED THE AIR CONDITIONING ACCESSORY UNIT (ACAU) TO BE INTERMITTENT OR FAILED INTERNALLY. REPLACED THE ACAU AND OPERATIONAL CHECK NORMAL.

LEFT PACK OUTPUT TEMPERATURE APPEARS TO BE WARMER THAN THE RIGHT PACK ON THE GROUND. PERFORMED BITE CHECK ON THE CABIN TEMPERATURE CONTROLLER PER THE FIM WITH NO FAULTS DISPLAYED. PERFORMED BITE CHECK OF LEFT AND RIGHT 35 DEG CONTROLLERS. CONTROLLER FAULT WAS DISPLAYED ON THE LEFT CONTROLLER. REPLACED LEFT 35 DEG CONTROLLER. OPERATIONAL CHECK NORMAL.

LEVEL 3 CORROSION FOUND ON THE UPPER SURFACES OF THE LEFT AND RIGHT WING UNDER THE EMERGENCY EXIT WING WALK PAINT. RIGHT WING UPPER SURFACE LOCATIONS STRINGERS 2,3,4,5,7,8 AND REAR SPAR AT APPROX WBL 71.24-92.5. LEFT WING UPPER SURFACE LOCATIONS STRINGERS 1,4,5,9 AND REAR SPAR AT APPROX WBL 71.24-92.5 AND 165-235. CORROSION DEPTH IS GREATER THAN THE SRM LIMITS AND REQUIRES ENGINEERING FOR REPAIRS.

THE RIGHT PACK TEMPERATURE INDICATOR SHOWED 0 DEGREES WITH THE RIGHT PACK OPERATING NORMALLY. THE FIRST ITEM TO CHECK IN THE FIM WAS THE PACK OUTLET TEMPERATURE BULB. THE LEFT AND RIGHT PACK TEMPERATURE BULBS WERE SWAPPED. WITH THE PACKS OPERATING, THE LEFT PACK SHOWED 0 DEGREES AND THE RIGHT WAS CORRECT. THIS INDICATED A FAILED TEMPERATURE BULB. THE TEMPERATURE BULBS WERE RETURNED TO THE PREVIOUS POSITIONS AND THE RIGHT TEMPERATURE BULB WAS REPLACED. OPERATIONAL CHECK OF THE PACKS NOW SHOWED CORRECT TEMPERATURES FOR BOTH SIDE.

THE NR 2 SOURCE OFF/ GENERATOR OFF LIGHT CAME ON IN CLIMB AND WOULD NOT RESET. ON THE GROUND, THE GENERATOR CONTROL UNIT SHOWED AN IDG FAULT LIGHT. RESET THE GCU AND PERFORMED AN ENGINE RUN WITH NO FAULTS RECURRING ON THE GCU. WHILE PERFORMING AN INSPECTION OF THE IDG, FOUND THE DIFFERENTIAL PRESSURE INDICATOR POPPED. INSPECTED THE IDG FILTER AND FOUND NO DEFECTS. EACH TIME THE DPI WAS RESET AND THEN AN ENGINE RUN WAS PERFORMED THE DPI WOULD POP IN A FEW MINUTES. REMOVED AND REPLACED THE IDG. OPERATIONAL CHECKS NORMAL.

THE STANDBY ALT SELECT KNOB ON THE PRESSURIZATION PANEL WAS FOUND TO BE INTERMITTENTLY SLIPPING INTERNALLY WHEN ATTEMPTING TO MAKE NUMBER CHANGES. REPLACED THE PANEL AND OPERATIONAL CHECK NORMAL.

NR 2 ENGINE FIRE LOOP LIGHT DID NOT TEST. WHILE PERFORMING RESISTANCE CHECKS ON THE #2 ENGINE LOOP A DETECTORS NOTICED RESISTANCE CHANGES WHEN THE FIRE DETECTOR HARNESS WAS MOVED OR DISTURBED. REPLACED THE FIRE LOOP HARNESS AND #2 FIRE LOOP LIGHT TESTED OK.

#2 ENGINE FIRE LOOP LIGHT DID NOT TEST. PERFORMED A BITE CHECK ON THE ENGINE FIRE DETECTION MODULE AND FOUND ENGINE 2 LOOP A CORE RIGHT FAULT DISPLAYED. REPLACED THE #2 ENGINE LOOP A CORE FIRE DETECTOR AND FIRE LOOP LIGHT TESTED OK.

DURING MAINTENANCE ENGINE RUNS, NOTED LEFT ENGINE BLEED PRESSURE WAS LOWER THAN THE RIGHT ENGINE AT IDLE POWER SETTINGS. THE LEFT ENGINE BLEED AIR PRESSURE WOULD RISE AND MATCH THE RIGHT PRESSURE ONCE THE POWER LEVERS WERE ADVANCED TO CHANGE THE ENGINE BLEED SOURCE FROM HIGH TO LOW STAGE. USING THE FIM AND A DESCRIPTION OF THE SYSTEM OPERATION DETERMINED EITHER THE HIGH STAGE REGULATOR OR HIGH STAGE VALVE TO BE AT FAULT. REPLACED THE HIGH STAGE REGULATOR AND NO PRESSURE INCREASE OCCURRED AT IDLE. SEE SDR COZA20161217101 FOR REPLACEMENT OF THE HIGH STAGE VALVE.

DURING MAINTENANCE ENGINE RUNS, NOTED LEFT ENGINE BLEED PRESSURE WAS LOWER THAN THE RIGHT ENGINE AT IDLE POWER SETTINGS. THE LEFT ENGINE BLEED AIR PRESSURE WOULD RISE AND MATCH THE RIGHT PRESSURE ONCE THE POWER LEVERS WERE ADVANCED TO CHANGE THE ENGINE BLEED SOURCE FROM HIGH TO LOW STAGE. USING THE FIM AND A DESCRIPTION OF THE SYSTEM OPERATION, DETERMINED EITHER THE HIGH STAGE REGULATOR OR HIGH STAGE VALVE TO BE AT FAULT. REPLACED THE LEFT HIGH STAGE VALVE. PERFORMED AN ENGINE RUN AND THE LEFT AND RIGHT ENGINE BLEED PRESSURES MATCHED AT IDLE POWER SETTINGS CORRECTING THE PROBLEM.

RIGHT ENGINE DRIVE LIGHT ILLUMINATED AT ENGINE START. USING THE FAULT ISOLATION MANUAL, DETERMINED RIGHT IDG TO HAVE AN INTERNAL FAULT THAT CAUSED AN AUTOMATIC DISCONNECT. REPLACED THE IDG AND OPERATIONAL CHECKED NORMAL.

LEFT RAM AIR DOOR ACTUATOR REPLACED AS PART OF TROUBLESHOOTING FOR A PACK LIGHT APPEARING ON RECALL.

RIGHT PACK LIGHT ILLUMINATED DURING RECALL TEST DURING DESCENT INTO OAKLAND. PERFORMED BITE CHECK ON RIGHT PACK/ZONE TEMPERATURE CONTROLLER PER FIM 21-61 TASK 801. FOUND RAM AIR ACTUATOR, TRIM VALVE ZONE FWD, TCV AND FLIGHT DECK TRIM AIR VALVE LIGHT ILLUMINATED. INSTALLED RIGHT CONTROLLER ON THE LEFT SIDE AND FOUND SAME LIGHTS ILLUMINATED ON LEFT SIDE. WHEN LEFT CONTROLLER WAS INSTALLED ON RIGHT SIDE NO FAULT LIGHTS ILLUMINATED. INSTALLED LEFT CONTROLLER IN ITS ORIGINAL POSITION. REMOVED AND REPLACED RIGHT PACK/ZONE TEMPERATURE CONTROLLER AND PERFORMED A BITE CHECK ON BOTH PACK/ZONE TEMPERATURE CONTROLLERS. NO FAULT LIGHTS ILLUMINATED.

PERFORMED ENGINE STARTER CHIP DETECTOR INSPECTION. FOUND EXCESSIVE METAL PARTICLES ATTACHED TO THE CHIP DETECTOR. REPLACED ENGINE STARTER.

PERFORMED AN OIL QUANTITY INSPECTION ON THE LEFT PACK AIR CYCLE MACHINE. FOUND THE OIL LEVEL BELOW LIMITS IN THE SIGHT GLASS AND SIGNS OF FLUID LEAKAGE FROM THE AIR CYCLE MACHINE. REPLACED THE LEFT PACK AIR CYCLE MACHINE.

FMC CDU ENGINE 1 BITE TEST SHOWED "OIL FILTER SIGNALS DISAGREE MESSAGE" 79-31121. FIM 79-05 TASK 817 WAS USED TO TROUBLESHOOT THE SYSTEM IN THE ORDER OF STEPS GIVEN. A VISUAL INSPECTION OF THE ELECTRICAL CONNECTORS AND RECEPTACLES OF THE OFDPS, EEC AND J7 HARNESS WAS ACCOMPLISHED WITH NO DEFECTS NOTED. A CHIP DETECTOR AND SCAVENGE SCREEN INSPECTION WAS COMPLETED ON THE LEFT ENGINE WITH NO METAL PARTICLES FOUND. THE CLOGGING TRANSMITTER S125 WAS REPLACED. THE REPAIR CONFIRMATION PART POWER LEAK CHECK WAS ACCOMPLISHED. NO OIL FILTER SIGNALS DISAGREE MESSAGE WAS DISPLAYED.