IO-540Lycoming IO-540

Parts most often named Magneto (111) · Impulse Coupling (30) · Bearing (26) · Block (21)

SLICK MAGNETO (MODEL NR 6350 [S/N removed]) FOLLOWER ARM OF CONTACTOR POINTS BROKE AFTER 76 HOURS SINCE NEW. THE BREAK OCCURRED AT THE BEND ON THE SIDE OF THE SPRINGY METAL FOLLOW ARM. THIS CAUSED THE MAGNETO TO FAIL (DEAD MAG) DURING BEFORE TAKEOFF MAGNETO CHECKS. THE BEND IN THE SIDES OF THE FLAT METAL SPRING FORMED A CRACK THAT PROGRESSED ACROSS THE METAL WHICH FAILED AFTER ONLY 76 HOURS IN [S/N removed]. PREVIOUS FOLLOWER ARMS WERE SLIGHTLY THICKER MATERIAL AND NO BEND ON SIDES OF FOLLOWER ARM.

THE MAGNETO IMPULSE COUPLER LOCKED UP AND BROKE THE GEARS INSIDE THE BACK OF THE ENGINE. THIS SHEARED THE DOWEL PIN IN THE BACK OF THE CRANKSHAFT CAUSING ENGINE STOPPAGE.

MAGNETO FAILURE, ENGINE STARTED RUNNING ROUGH. PILOT COULD HEAR WHAT WAS DESCRIBED AS A RUBBING SOUND. THE MAGNETO WAS SENT BACK TO THE MANUFACTURER. INSTALLED A REPLACEMENT MAGNETO, AND IT FAILED WITH IN 1.5 HOURS. FAILED IGNITION MAG CHECK. ROUGH RUNNING. AFTER REMOVING THE MAGNETO, COULD HEAR SMALL PARTS RATTLING AROUND INSIDE.

Parts most often named Cylinder (43) · Exhaust Valve (27) · Pushrod (25) · Intake Valve (15)

DURING PREFLIGHT PILOT NOTICED THE ENGINE HAD AN OIL LEAK. MAINTENANCE INSPECTED AND DETERMINED THAT THE CRANKCASE NEAR NUMBER 6 CYLINDER WAS CRACKED NEAR THE FORWARD UPPER CYLINDER HOLD DOWN STUD.

DURING BORE SCOPE INSPECTION OF CYLINDER ASSEMBLIES THE NUMBER 3 CYLINDER EXHAUST VALVE WAS FOUND TO BEY HEAVILY PITTED ON VALVE BELL. THE ENGINE HAS ACCUMULATED 398.4 HOURS SINCE MAJOR OVERHAUL. NEW CYLINDER ASSEMBLIES INCLUDING VALVES WERE INSTALLED AT OVERHAUL AT ENGINE TOTAL TIME 2041.0. THIS IS THE JUST LATEST EVENT IN A GROWING TREND OF INTAKE AND EXHAUST VALVE DEFECTS AND FAILURES IN OUR FLEET OF LYCOMING POWERED AIRCRAFT.

DURING A SCHEDULED VISUAL INSPECTION OF THE ENGINE, EVIDENCE OF OIL SEEPING FROM THE CYLINDER ROCKER BOX COVER AREA WAS DISCOVERED ON TWO CYLINDERS. USING SOAP BUBBLES AND AIR, OIL SEEP WAS ISOLATED TO SEVERAL SMALL PIN HOLES AROUND THE RAISED STAMPED AREA ON THE ROCKER BOX COVER WHERE "LYCOMING" IS STAMPED. FURTHER INSPECTION WITH A 10X MAGNIFYING GLASS CONFIRMED THE STAMPED AREA TO HAVE SMALL HOLES/CRACKS DIRECTLY AROUND THE EDGES OF THE STAMPED LETTERING.

Parts most often named Crankcase (17) · Crankshaft (14) · Camshaft (9) · Connecting Rod (9)

THIS ENGINE HAS BEEN REMOVED FROM [S/N removed] DUE TO A CRACK ON THE RT SIDE OF THE CASE BELOW THE NR 3 CYLINDER AT THE FORWARD LOWER CYLINDER HOLD DOWN NUT. CRACK STARTS FROM THE FORWARD LOWER CYLINDER HOLD DOWN NUT AND CONTINUES ABOUT 3 INCHES. ENGINE REMOVED FROM AIRCRAFT REFERENCING PA-32-301 MAINTENANCE MANUAL SECTION 71-00-04.

PILOT REPORTED, ENGINE MADE A LOUD NOISE THEN LOST POWER AND STOPPED TURNING. AIRCRAFT WAS FORCED TO MAKE A LANDING IN SEMI-FROZEN TUNDRA AND FOLDED THE NOSE GEAR, FOLDED RIGHT HAND MAIN LANDING GEAR, AND BROKE LEFT HAND MAIN LANDING GEAR AXLE. ENGINE TEAR DOWN INSPECTION SHOWED THAT THE CRANKSHAFT HAD BROKE AT NUMBER THREE MAIN BEARING JOURNAL.

ENGINE LOST POWER IN FLIGHT, RESULTING IN AN EMERGENCY LANDING. INSPECTION REVEALED THAT THE NUMBER 1 CYLINDER INTAKE VALVE FAILED, DAMAGING THE PISTON.

Parts most often named Pump (82) · Diaphragm (3) · Motor (1) · Drive Shaft (1)

(CAN) AUXILIARY FUEL PUMP LOW PRESSURE WARNING ILLUMINATED DURING FLIGHT. PUMP REPLACED AFTER LANDING. DEFECT RECTIFIED.

(CAN) THE FUEL PUMP WAS NOTED TO BE LEAKING FUEL BY GROUND CREWS AFTER 2.1 HOURS’ TIME SINCE NEW. THE FUEL PUMP HAD BEEN INSTALLED NEW ON THE ENGINE. AS PART OF A NEW EXCHANGE ENGINE PURCHASED & INSTALLED DURING AN OVERHAUL. THE FUEL PUMP WAS LEAKING FROM THE OVERBOARD DRAIN HOSE, WHICH IS A TATTLE TALE THAT CAN EITHER LEAK ENGINE OIL OR FUEL, DEPENDING ON WHICH PART OF THE FUEL PUMP FAILS.

DURING CLIMB THE PILOT REPORTED THE RT FUEL PRESS WOULD NOT REMAIN IN THE GREEN ARC. THE ENG DRIVEN FUEL PUMP WAS REPLACED & OPERATIONAL & LEAK CHECK WERE ACCOMPLISHED NO DEFECTS NOTED. THE ACFT WAS RELEASED FOR A FLIGHT CHECK & NO DISCREPANCY WAS REPORTED.

Parts most often named Starter (56) · Gear (5) · Drive Gear (2) · Ring Gear (2)

(CAN) DURING ACFT 50 HR INSPECTION, THE STARTER WAS FOUND TO HAVE A CRACK APPROXIMATELY 1.5" IN LENGTH IN THE GEAR CASING. STARTER REPLACED.

(CAN) ON ENGINE START PILOT NOTED A BANG THEN THE STARTER MOTOR SPUN UP FAST. HE GOT OUT TO INVESTIGATE AND FOUND THE BENDIX GEAR LAYING ON THE GROUND. THE GEAR SHAFT SHEARED ON THE FWD END IN SIDE OF THE STARTER HSG. IT APPEARS TO HAVE BEEN CRACKED FOR SOME TIME. A NEW STARTER WAS INSTALLED.

(CAN) DURING ENGINE START, STARTER WOULD NOT ENGAGE THE FLYWHEEL. STARTER WAS REPLACED WITH [S/N removed] UNIT. NEW STARTER FUCTION TESTED, NO DEFECTS FOUND.

Parts most often named Starter Gen (41) · Housing (5) · Gear (5) · Starter (3)

THE STARTER BENDIX DRIVE WOULD STICK OUT AND GET STUCK ON RT WING GEAR AND WOULD NOT RETRACT. THE STARTER WOULD NOT TURN ENGINE OVER.

(CAN) DURING A DI CONDUCTED BY MX IT WAS NOTED THAT THE HOUSING WAS FOUND CRACKED. STARTER RING GEAR WAS ALSO REPLACED DUE TO DAMAGED TEETH. STARTER WAS REPLACED AND NO ISSUES ISSUES WERE NOTED.

(CAN) GRINDING NOISE WAS HEARD DURING START. ONE CORNER OF THE MOUNT FLANGE WAS FOUND BROKEN OFF DURING REMOVAL. STARTER WAS REPLACED AND NO FURTHER ISSUES WERE NOTED.

Parts most often named Engine (32) · Manifold (3) · Crankcase (2) · Gear (2)

PILOT REPORTED ENGINE SHUT DOWN AND FEATHERED ON ITS OWN ON TAKE-OFF. MAINTENANCE INSPECTED THE LT AND RT ENGINE FUEL SYSTEM, INTAKE SYSTEM, IGNITION SYSTEM AND PROPELLER. PERFORMED LT AND RT ENGINE FULL POWER RUN UP SEVERAL TIMES WITH ALL PARAMETERS GOOD. NO DISCREPANCIES FOUND. AIRCRAFT WAS RETURNED TO [S/N removed] AND HAS BEEN OPERATING NORMALLY.

DURING INSPECTION OF RIGHT ENGINE AFTER FAILED ENGINE CHANGE FUNCTIONAL CHECK FLIGHT; MAINTENANCE NOTED LARGE AMOUNTS OF METAL IN OIL SAMPLES. FURTHER INVESTIGATION REVEALED DAMAGED SPARK PLUGS, PISTON, AND CYLINDER WALL AT THE NR 2 CYLINDER. DURING REMOVAL OF CYLINDER AT INSTRUCTION OF LYCOMING, UNIDENTIFIABLE OBJECT WAS FOUND IN SECTION OF INTAKE TUBE. NR 2 CYLINDER ASSEMBLY, INCLUDING PISTON, AND THE OIL SUMP WERE REPLACED WITH [S/N removed] PARTS.

PILOT REPORTED THAT IN FLIGHT, ENGINE MADE SOME NOISES FOLLOWED BY LOSS OF ENGINE POWER, LT ENGINE. PROP WENT TO UN-COMMANDED FEATHER WITH A SUDDEN INCREASE IN RPM BEFORE ENGINE STOPPED RUNNING. INVESTIGATION ON THE GROUND REVEALED NO MOVEMENT OF THE PISTONS IN CYLINDERS 3, 4, 5, 6 ON LT ENGINE WITH PROP ROTATION, BUT PISTONS IN NR 1 AND 2 CYLINDERS ARE MOVING WITH PROP ROTATION. NO DISASSEMBLY OF ENGINE HAS BEEN DONE, BUT SUSPECT THAT THE CRANKSHAFT HAS BROKEN BETWEEN CYLINDERS 1 AND 2 AND 3 AND 4.

Parts most often named Oil Filter (6) · Baffle (6) · Seal (5) · Gasket (4)

THE OIL RELIEF SPRING WAS DEFORMED AND THE FILTER WAS OFF THE SEAL ALLOWING OIL TO BYPASS THE FILTER. THE ENGINE WAS PROBABLY STARTED WITH COLD OIL CAUSING THE FILTER TO COME OFF THE SEAT AND DEFORM THE SPRING. THE FILTER WAS NOT CLOGGED WITH ONLY 23 HOURS ON THE OIL.

PILOT REPORTED MINOR ENGINE SURGING DURING FLIGHT. AFTER TROUBLESHOOTING AND REPAIRS, FOUND TO BE THE ENGINE DRIVEN FUEL PUMP INTERMITTENTLY DROPPING FUEL PRESSURE. ON INVESTIGATION THE OIL SEAL IN THE DIAPHRAGM PUMP WAS FOUND TO BE LEAKING AND OIL WAS IN THE AIRSPACE ABOVE THE DIAPHRAGM AND ALMOST COMPLETELY FILLING ONE SIDE UNDER THE LOWER DIAPHRAGM.

OPERATOR WAS COMPLAINING OF HIGHER THAN NORMAL OIL TEMPERATURES. FOUND VERNATHERM VALVE TO HAVE BROKEN. THE NUT THAT HOLDS THE SEATING VALVE HAD BROKEN OFF THE THREADED PORTION OF THE PART. IT HAD BROKEN WHERE A ROLL PIN SECURES THE NUT TO THE THREADS. THE NUT WAS FOUND IN THE OIL COOLER HOSE WHERE IT COMES OFF THE ACCESSORY CASE GOING TO THE COOLER AND HAD RESTRICTED THE FLOW ENOUGH TO THE COOLER THAT CREATED THE HIGHTER TEMPERATURE. THE FAILED PART WAS NOT OEM BUT A MFG PART.

Parts most often named Servo (11) · Fcu (4) · Fuel Servo (2) · Fuel Control (2)

WITH A FACTORY OVERHAULED ENGINE, THE FUEL SERVO FAILED AFTER 32.4 HOURS. AFTER REPAIRED IT LASTED 12.2 HOURS. THEN INSTALLED A NEW SERVO AND IT ONLY LASTED 3 HOURS. ALL THREE FAILURES WERE THE SAME, THE MIXTURE SHAFT CAME OUT SLIGHTLY CAUSING A MISALIGNMENT WITHIN THE SERVO WHILE ATTEMPTING RE-START. THIS COULD BE A SERVO PROBLEM AND OR A FUEL SYSTEM PROBLEM. HAVE YET TO CONFIRM WHAT IS CAUSING THIS PROBLEM. A [S/N removed] OLDER STYLE SERVO SEEMS TO BE ABLE TO OPERATE FINE ON THIS ENGINE.

(CAN) DURING SCHEDULED INSPECTION OF THE AIRCRAFT, THE FCU MIXTURE ARM WAS FOUND TO BE STIFF AND OPERATION DID NOT IMPROVE AFTER LUBRICATION. FCU REPLACED.

INSPECTED FUEL SERVO PLUG IAW SBPRS-107, REVISION 1, DATED MARCH 6, 2008. NO DAMAGE FOUND ON THE THREADS OF THE PLUG OF THE SERVO UNIT. INSTALLED PLUG AND SAFETIED IAW INSTRUCTIONS.

Parts most often named Controller (15) · None (6) · Governor (6) · Tachometer (2)

(CAN) ENGINE TACH WAS NOT READING AND THE GOVERNOR WAS NOT WORKING. TACH POINTS ON THE MAGNETO FOUND FAULTY UPON REMOVAL AND INSPECTION.