PA-31Navajo · Chieftain

Parts most often named Crankcase (37) · Camshaft (34) · Crankshaft (26) · Stud (17)

AT CRUISE ALTITUDE, AN OIL PRESSURE FLUCTUATION WAS OBSERVED ON NO.1 ENGINE INSTRUMENTS. ALSO NOTICED A SMALL OIL STREAK ON NO. 1 ENGINE COWL. DECISION WAS IMMEDIATELY MADE TO RETURN TO BASE, FOR FURTHER INVESTIGATION BY ENGINEERS.

(CAN) DURING REGULAR OIL CHANGE ABNORMAL AMOUNTS OF FERROUS METAL NOTED IN OIL FILTER INSPECTION. CYLINDERS NR 4 & 6 REMOVED FOR INSPECTION & DISCOVERED GALLING DAMAGE TO CYLINDER NR 6 EXHAUST LOBE & CAM FOLLOWER. ENGINE REMOVED FOR REPAIR.

(CAN) DURING REPETITIVE TROUBLESHOOTING FOR REPORTED LT ENGINE OIL LEAK, MAINTENANCE FOUND ENGINE CRANK CASE CRACKED APPROXIMATELY 6" LONG, EXTENDING FROM NR 6 CYLINDER BASE, UPWARD INTO CASE. ENGINE WILL BE REPLACED.

Parts most often named Cylinder (83) · Stud (17) · Cylinder Head (12) · Valve Seat (11)

PILOT REPORTED ENGINE NOT MAKING POWER. FOUND EXHAUST ROCKER SHAFT HOLDER BROKEN AND NO LONGER ATTACHED TO CYLINDER ASSEMBLY. CAUSING EXHAUST VALVE TO NOT OPEN WHEN REQUIRED.

RIGHT ENGINE #1 CYLINDER INDICATED ZERO DURING A COMPRESSION CHECK. UPON CLOSER EXAMINATION A CRACK WAS DISCOVERED AROUND THE UPPER SPARK PLUG HOLE THAT EXTENDED INTO THE INTAKE PORT BETWEEN COOLING FINS 14 AND 15. THIS IS THE 2ND FAILURE ON THIS AIRCRAFT AND THE 3RD TOTAL AMONG BOTH COMPANY AIRCRAFT.

PILOT REPORTED ROUGH RUNNING ENGINE AFTER START UP. INVESTIGATION BY MAINTENANCE DETERMINED THAT THE #3 CYLINDER EXHAUST VALVE SEAT/VALVE HAD DROPPED OUT OF CYLINDER HEAD. LYCOMING FACTORY OVERHAULED ENGINE WITH 637.5 TSOH, 1646.2 TTSN.

Parts most often named Turbocharger (52) · Bearing (12) · Seal (8) · Bolt (8)

PILOT WAS IN CRUISE FLIGHT AND EXPERIENCED A PARTIAL POWER LOSS AND THEN OIL PRESSURE LOSS OF THE RIGHT ENGINE. PILOT SHUT DOWN ENGINE AND LANDED WITHOUT FURTHER INCIDENT. UPON INSPECTION OF ENGINE IT WAS FOUND THAT THE SHAFT WAS BROKEN AND BOTHER TURBINE AND COMPRESSOR BLADES WERE DAMAGED. TURBO WAS A RECENT INSTALL AFTER OVERHAUL BY ATC AND HAD 87.9 HOURS TSO. MECHANICS VERIFIED THAT THE TURBO WAS PRE-OILED PRIOR TO RETURN TO [S/N removed] AND NO ISSUES WERE REPORTED POST-INSTALL.

DURING ROUTINE 100 HOUR INSPECTION, THE LEFT TAILPIPE WAS FOUND TO HAVE BURNT OIL ON IT. THE TAILPIPE WAS REMOVED FOR FURTHER INVESTIGATION AND BURNT OIL WAS VISIBLE IN THE TURBOCHARGER AROUND THE TURBINE BEARING. DUE TO THIS OIL LEAK THE TURBOCHARGER WAS REMOVED AND REPLACED WITH [S/N removed].

(CAN) PILOTS REPORTED LEFT DE-ICE BOOT WAS NOT INFLATING. UPON INSPECTION THE DE-ICE LINE RUNNING THROUGH THE LT NACELLE WAS COMPLETELY MELTED. THE UPPER TAIL-PIPE COMING OUT OF THE TURBOCHARGE HAD SPLIT AND TORN, ALLOWING HOT EXHAUST GASES TO HIT THE FIREWALL AND SEEP THROUGH THE COWL FLAP HINGE CUT OUTS. THE DEICE LINE SAT RIGHT BEHIND THE COWL FLAP HINGE. NO OTHER DAMAGE WAS FOUND IN THE NACELLE AREA.

Parts most often named Downlock (13) · Arm (9) · Rod End (8) · Hook (7)

NOSE GEAR WARNING LIGHT DID NOT ILLUMINATE WHEN EXTENDED. LIGHT CAME ON AT TOUCH DOWN. LUBED GEAR AND AJUSTED NOSE ACTUATOR. TEST GOOD. AMENDMENT TO 2022F00098 02/23/2022 ONLINE

LH MLG RED LIGHT ON WHEN GEAR SUPPOSED TO BE DOWN. CYCLED GEAR, PUMPED GEAR DOWN, ACTIVATED NITROGEN BOTTLE TO BLOW DOWN. NO CHANGE. VISUAL CONFIRMATION GEAR WAS DOWN AND A/C LANDED.

PILOT REPORTED THAT HE WAS NOT GETTING A DOWN AND LOCK INDICATION ON LEFT MAIN. AFTER HE WAS ON GROUND, INSPECTION REVEALED THAT THE LEFT RETRACT ARM PN 42042-000 WAS CRACKED AND SEPARATED SUFFICIENTLY ENOUGH TO PREVENT THE DOWN LOCK SWITCH FROM CLOSING. REPLACED RETRACT ARMS ON BOTH SIDES OF ACFT, AFTER LEARNING OF PIPER SL 1092C.

Parts most often named Magneto (65) · Capacitor (12) · Distributor Blk (11) · Coil (8)

THE RT ENGINE WOULD NOT START OR EVEN FIRE. A STARTER VIBRATOR SYSTEM IS USED AND WAS FOUND TO BE FUNCTIONAL THROUGH TROUBLESHOOTING. THE LT MAGNETO WAS REMOVED, DISASSEMBLED. INSPECTION FOUND THAT THE PLASTIC COM LOBE HAD SIGNIFICANT WEAR CAUSED BY PRIMARY BREAKER TAB CONTACTING THE RETARD BREAKER AND NOT BEING ABLE TO FULLY OPEN. THIS CONTACT AND WEAR ON THE LOBE PREVENTED THE RETARD BREAKER FROM FULLY OPENING. THIS MAGNETO WAS PART OF A NEW ZERO TIMED ENGINE WITH ONLY 12.8 HRS TIS.

PILOT WENT TO DEPART AND COULD NOT GET THE RT ENGINE TO START. MAINTENANCE WAS DISPATCHED TO THE AIRCRAFT AND FOUND THE POINTS ON THE RT ENGINE LT MAG WERE NOT OPENING. REPLACED POINTS, TIMED ENGINE AND RETURNED TO BASE.

EXPERIENCED ENGINE ROUGHNESS ON LEFT ENGINE, 5-10 MINUTES AFTER DEPARTURE, AT CRUISE ALTITUDE OF APPROXIMATELY 2,500 FEET MSL. ISOLATED THE PROBLEM TO THE RIGHT SIDE OF LEFT ENGINE DUAL MAGNETO AND CONTINUED THE FLIGHT ON THE LEFT SIDE OF DUAL MAGNETO(RIGHT SIDE COCKPIT SWITCH OF DUAL MAGNETO TURNED OFF ON LEFT ENGINE UNTIL REACHING THE AIRPORT.

Parts most often named Regulator (39) · Heater (8) · Valve (7) · Switch (7)

PILOT REPORTED SMOKE IN THE COCKPIT UNKNOWN LOCATION. UPON INVESTIGATION BY OUR LEAD MECHANIC WE FOUND THE HEATER FLAMED OUT. OPS CHECKED GOOD NO DEFECTS WERE FOUND. AND AIRCRAFT RETURNED TO [S/N removed]. THE JANITROL HEATER WAS CLOSE TO TBO. AND WAS REPLACED WITH A OVER HAULED HEATER. THE FOLLOWING MONTH.

HEATER SMELLED HOT DURING DESCENT. MAINTENANCE INSPECTED THE HEATER NO EXTERNAL DEFECTS NOTED. FURTHER INSPECTION REVEALED THAT THE COMBUSTION BLOWER MOTOR AND FUEL REGULATOR REQUIRED REPLACEMENT IN ORDER TO RETURN THE HEATER TO A [S/N removed] CONDITION.

PILOT REPORTS SMELLS OF RAW FUEL AFTER SHUTTING OFF HEATER. MAINTENANCE INSPECTED AND REPLACED COMBUSTION AIR BLOWER MOTOR BRUSHES, NO FURTHER DEFECTS NOTED.

Parts most often named Switch (41) · Downlock Switch (12) · Bulb (5) · Downlock (4)

GEAR NOT LOCKED LIGHT ILLUMINATED. FOUND LEFT UPLOCK ROD ASSEMBLY WOULD NOT EXTEND AND ALLOW HOOK TO FULLY CAPTURE ROLLER ON LOWER STRUT ASSEMBLY. CLEANED INSPECTED AND UPLOCK ROD ASSEMBLY, CYCLED GEAR SEVERAL CYLES ON JACKS AND FOUND OPERATION SATISFACTORY.

DURING APPROACH THE PILOT SELECTED THE LG HANDLE TO THE EXTEND POSITION, RECEIVED GREEN DOWN & LOCKED LIGHTS ON THE NOSE & LT MAIN GEAR, THE RT MAIN GEAR REMAINED OFF. PILOT TRIED TO MANUALLY EXTEND THE LG WITH THE SAME INDICATION. DIVERTED, DECLARED AN EMER & LANDED WITHOUT FURTHER INCIDENT. TROUBLESHOOTING REVEALED A FAULTY RT MLG DOWN LOCK LIMIT SWITCH. R & R SWITCH. PERFORMED OPERATIONAL CHECK OF LG SYS, ALL SYSTEMS CHECKED WERE NORMAL.

LANDING GEAR DID GIVE A DOWN LOCK INDICATION ON THE LT MLG. PILOT PERFORMED TOWER FLY-BY & TOWER CONFIRMED ALL THREE LG VISIBLE. PILOT THEN MADE A HIGH SPEED PRECAUTIONARY LANDING & CONFIRMED ALL THREE LG DOWN & LOCKED. PILOT THEN LANDED THE ACFT.

Parts most often named Pump (54) · Fuel Pump (6) · Shaft (4) · Gasket (4)

DURING FLIGHT, THE PILOT REPORTED THAT RIGHT ENGINE HAD FUEL FLOW FLUCTUATIONS THAT CAUSED INTERMITTENT ENGINE POWER LOSS. SHUTDOWN AND SECURED THE ENGINE. AIRCRAFT LANDED SAFELY. MAINTENANCE INSPECTED THE AIRCRAFT AND DETERMINED THAT THE RIGHT ENGINE DRIVEN FUEL PUMP HAD FAILED. MAINTENANCE REPLACED THE DEFECTIVE PUMP. NO FURTHER DEFECTS WERE NOTED.

ENGINE WOULD NOT SHUT DOWN WITH MIXTURE CONTROL AT IDLE CUTOFF. FOUND ENGINE DRIVEN FUEL PUMP LEAKING FROM RELIEF VALVE INTO DECK PRESSURE REFERENCE LINE INTO INTAKE. ENGINE DRIVEN FUEL PUMP REPLACED WITH NEW.

OVERHAULED ENGINE DRIVEN FUEL PUMP FAILED AFTER 23.2 HOUR TIS. FUEL PUMP FAILED TO MAINTAIN FUEL PRESSURE AT IDLE RPM. MAJOR PROBLEM INDUSTRY WIDE.

Parts most often named Engine (52) · Tube (2) · Pushrod (1) · Support Bracket (1)

PILOT PERFORMED PRECAUTIONARY INFLIGHT ENGINE SHUTDOWN OF THE LEFT ENGINE DUE TO THE FOLLOWING: CHT INDICATING 500, OIL PRESSURE HIGH RED LINE, OIL TEMP CREEPING UP TOWARDS 200. ENGINE CONFIGURATION AS FOLLOWS: COWL FLAPS OPEN, MANIFOLD PRESSURE OF 20'. MAINTENANCE IS ASSESSING THIS CONDITION, NO FURTHER INFORMATION AT THIS TIME.

PILOT REPORTED " RIGHT ENGINE FAILURE ON TAKEOFF". MAINTENANCE INSPECTED THE RIGHT ENGINE AND DETERMINED THAT THE HARDWARE FOR #2 ENGINE , #2 CYLINDER INTAKE TUBE WAS LOOSE. REMOVED ASSOCIATED GASKET AND O-RING FOR INTAKE TUBE AND SECURED INTAKE TUBE AS REQUIRED. ENGINE GROUND RUNS WERE PERFORMED WITH NO OTHER DISCREPANCIES NOTED.

DURING CRUISE FLIGHT, THE PILOT REPORTED THAT THE RT ENG OIL PRESS DROPPED INTO THE YELLOW RANGE. THE PILOT REPORTED THAT THE MANIFOLD PRESS STARTED TO FLUCTUATE, AT THIS POINT THE PILOT ELECTED TO PERFORM A PRECAUTIONARY SHUTDOWN OF THE RT ENG. THE PILOT DECLARED AN EMER & LANDED WITHOUT INCIDENT. FOUND THE RT ENG HAD EXCESSIVE METAL IN THE MAIN OIL FILTER, SUSPECT THE OIL PUMP IS FAILING. THE RT ENG REPLACEMENT IS IN PROGRESS.

Parts most often named Valve (37) · Vernatherm (7) · Bypass Valve (3) · Nut (2)

AFTER 162.0 HOURS OF OPERATION SMOH THE RIGHT ENGINE OIL TEMPERATURE WAS REPORTED TO STILL BE 20 TO 30 DEGREES HIGHER THAN LEFT ENGINE AND IN WARMER AIR TEMPERATURES THE COWL FLAP NEEDED TO BE OPENED TO KEEP IN THE GREEN. DURING TROUBLESHOOTING IT WAS DISCOVERED THAT THE VERNATHERM OIL CONTROL VALVE SPRING AND PLUNGER STUD HAD FAILED AT RETAINING NUT DRIFT PIN LOCATION. A NEW REPLACEMENT VALVE WAS INSTALLED RESULTING IN SATISFACTORY OIL TEMPERATURE.

LOOSE CRIMP NUT FOUND AS DESCRIBED IN MFG MANDATORY SB NR 518C. IAW SB 518C, THE THERMOSTATIC BYPASS VALVE FOUND FAULTY IS NOT ONE OF THE AFFECTED MODELS LISTED. WE RECOMMEND THAT 518C SHOULD BE UPDATED TO INCLUDE ANY BYPASS VALVE USING THE CRIMPED NUT.

(CAN) IN CRUISE, THE PILOT NOTICED THAT THE RT ENGINE OIL TEMP WAS CLIMBING TO THE RED LINE WITH A DECREASE IN OIL PRESSURE. THE PILOT DECIDED TO SHUT DOWN AND SECURE THE ENGINE ONCE THE OIL TEMP REACHED THE RED LINE. THE PILOT RETURNED TO BASE WITHOUT INCIDENT. MX FOUND THAT THE VERNATHERM VALVE SPRING WAS BROKEN AND WAS PROTRUDING OVER THE SEAT WHICH WOULD NOT ALLOW THE VERNATHERM TO DIRECT THE OIL THROUGH THE OIL COOLER. A NEW VERNATHERM VALVE WAS INSTALL AND THE ENGINE OIL TEMP RETURNED TO NORMAL.