PA-34Seneca

Parts most often named Servo (57) · Controller (12) · Fuel Control (2) · Joint (1)

(AUS) ENGINE FCU SERVO STEM SEAL LEAKING FUEL. FURTHER INVESTIGATION FOUND THAT THERE WERE MANY SMALL PARTS OF BLUE RUBBER THROUGH OUT THE UNIT. THESE RUBBER PARTS HAD COME FROM A POSSIBLE DAMAGED O RING SEAL DURING ASSEMBLY. ON TOTAL STRIP OF THE UNIT NONE OF THE O RINGS SHOWED SIGNS OF DAMAGE INDICATING THAT THE DAMAGED ORING MAY HAVE BEEN CHANGED BUT THE RUBBER NOT REMOVED.

COULD NOT ADJUST OVERLY RIGHT MIXTURE. SENT FOR FACTORY [S/N removed]. INSTALLED ON AIRCRAFT STILL COULD NOT ADJUST. SENT BACK TO FACTORY FOR REPAIRS. NOTE THESE UNITS ARE INSTALLED ON NEW AIRCRAFT, THIS IS 3RD SET OF [S/N removed] ON THIS AIRCRAFT.

FUEL SERVO GOUGED AT BASE BY SHOCK MOUNT ATTACHED TO ENGINE. SUBMITTED STATED SHOCK MOUNT DOES NOT COVER COMPLETE BASE OF SERVO. (X)

Parts most often named Tube (7) · Mount (4) · Line (4) · Link Assy (4)

AFTER A NORMAL LANDING, THE AIRCRAFT ROLLED 50 FT AND THE NLG COLLAPSED. DURING INSPECTION, FOUND THE NLG DOWNLOCK LINK ASSY BROKEN.

WHEN MOVING THE GEAR SELECTOR SWITCH TO THE GEAR UP POSITION FOLLOWING TAKEOFF, THE GEAR SELECTOR SWITCH PHYSICALLY BROKE OFF AT THE STEM, BETWEEN THE SWITCHES PIVOT POINT AND THE ROUND PLASTIC HANDLE, NEAR THE DETENT USED TO KEEP THE SWITCH IN THE GEAR-UP POSITION DURING FLIGHT. THIS IS NOT THE FIRST TIME THAT A LANDING GEAR SWITCH HAS FAILED THIS WAY: A SIMILAR INCIDENT TOOK PLACE WITH THIS AIRCRAFT MARCH 10, 2009.

UPON LANDING, GEAR EXTENSION, DURING APPROACH TO LANDING, PILOT NOTED AN EXCEPTIONALLY LONG TIME BETWEEN GEAR SWITCH ACTUATION AND INDICATION OF ALL DOWN AND LOCKED. OUTSIDE TEMP +9 F. BELIEVE THAT SWITCH ARM FOR DOWNLOCK HAD FROZEN IN PLACE (UP) AND REQUIRED TIME TO ACTUATE. (K)

Parts most often named Cylinder (15) · Stud (6) · Tube (5) · Retainer (3)

ROCKER ARM SHAFT RETAINER CONTINENTAL P/N # 631996. FOUND CRACKED RETAINERS DURING ANNUAL INSPECTION WHILE PERFORMING VISUAL INSPECTION. ORDER REPLACEMENTS. OLD PARTS ARE CAST AND NEW STYLE REPLACEMENT WITH SAME PART NUMBER LOOKS TO BE BILLET.

PILOT NOTED REDUCTION IN MANIFOLD PRESSURE AND OIL PRESSURE ON LT ENGINE. PILOT REDUCED POWER TO IDLE AND REQUESTED LANDING AT NEAREST AIRPORT. POST LANDING INSP OF ENGINE REVEALED CRACK IN CYLINDER WALL AND PART OF PISTON MISSING.

(CAN) ON ROUTINE INSP, NR 4 CYL UPPER CTR HOLD DOWN STUD WAS FOUND [S/N removed] OFF. THE CYL WAS REMOVED AND A WASHER WAS FOUND IN BETWEEN CYL AND CRANKCASE. THIS CAUSED CYL TO BE ON SLIGHTLY ANGLED CAUSING STRESS ON THE HOLD DOWN STUDS CAUSING ONE TO BREAK. ENGINE WAS REMOVED FOR INSP AND OR REPAIR. CRANK CASE HAD DAMAGE WHERE THE WASHER CONTACTED THE CASE. CYLINDERS HAD NOT BEEN REMOVED SINCE LAST O/H. ABOUT 1550 AIRTIME HOURS AGO.

Parts most often named Crankshaft (10) · Crankcase (7) · Bearing (2) · Cotter Pin (2)

(CAN) DURING A ROUTINE INSPECTION, A CRACK WAS DISCOVERED ON THE ENGINE CRANKSHAFT FLANGE, WHERE THE PROPELLER MOUNTS. THE CRACK WAS VERY SEVERE AS VERY TINY PIECES OF THE FLANGE HAD BROKEN OFF. THE CRACK APPEARS TO EXTEND THROUGH THE FLANGE OTBD OF THE DOWEL PIN HOLE TO THE RADIUS AND POSSIBLY AROUND THE RADIUS OF THE CRANKSHAFT. THERE HAVE BEEN NO REPORTED OR DOCUMENTED PROPELLER STRIKES SINCE THE ENGINE WAS INSTALLED APRIL OF 2012, FOLLOWING AN O/H.

DURING ANNUAL INSP, OIL WAS FOUND AT FRONT OF ENGINE. FURTHER INVESTIGATION REVEALED A CRACK OF THE CRANKSHAFT AT THE PROP MOUNTING FLANGE. CAUSE HAS NOT BEEN DETERMINED. (K)

DURING THE PROCESS OF INSPECTING (6 EA) CONNECTING RODS IAW SB 07-1 AND SB 00-3, IT WAS FOUND THAT ALL WRIST PIN BUSHINGS WERE INSTALLED NOT IAW THEIR POSITIONS AS REQUIRED IN THE APPLICABLE SB AS REFERENCED. SPLIT LINE OF BUSHING ON WRONG SIDE OF CENTERLINE. PARTS AS RECEIVED FROM MFG. (K)

Parts most often named Pump (24) · Fuel Pump (3) · Shaft (1) · Pump Valve (1)

LEFT ENGINE FUEL FLOW DROPPED FROM 25 GALLONS AN HOUR AT TOP OF CLIMB TO 7 GALLONS AN HOUR AT ALL POWER SETTINGS. ELECTRIC FUEL PUMP SWITCH ALSO FAILED. PILOT USED ENGINE PRIMER BUTTON TO KEEP ENGINE RUNNING. USE OF PRIMER BUTTON INCREASED FUEL FLOW TO 25 GALLONS AN HOUR. ALL OTHER ENGINE ENGINE INDICATIONS WERE NORMAL.

INSTALLED A FACTORY REMANUFACTURED ENGINE FROM CONTINENTAL THAT CAME WITH A NEW FUEL PUMP. UPON DOING THE ENGINE GROUND RUNS AND INITIAL ENGINE SET UP THE FUEL PUMP WOULD NOT SHUT OFF THE FUEL AFTER THE MIXTURE HAD BEEN PULLED BACK. INSPECTED SYSTEM FOUND TO HAVE A DEFECTIVE FUEL PUMP, REPLACED FUEL PUMP WITH A FACTORY NEW PUMP FROM CONTINENTAL. NO FURTHER ACTION NEEDED.

PILOT SQUAWKED THAT THE FUEL FLOW FOR THE RIGHT ENGINE WAS LOW AND ERRATIC IN-FLIGHT. MAINTENANCE INSPECTED AND TRIED TO ADJUST THE FUEL SYSTEM, REPLACED FUEL PUMP. NO FURTHER ACTION NEEDED.

Parts most often named Magneto (6) · Distributor Blk (3) · Distributor Gear (3) · Coil (2)

POINTS WERE FOUND NOT MAKING CONTACT, UPON FURTHER EXAMINATION, FOUND THE STATIONARY CONTACT LOOSE IN MAG. IT SEEMED TO HAVE COME OFF THE END, THE CONTACT DISK SEPARATED FROM THE BASE. (K)

PILOT REPORTED A "POPPING" SOUND COMING FROM THE LT ENGINE, AFTER INVESTIGATION MAINT FOUND THAT THE LT ENGINE LT MAGNETO CAM FOLLOWER EXCESSIVELY WORN. REPLACED MAGNETO AS NEEDED NO FURTHER PROBLEMS NOTED. (K)

WHILE PERFORMING AD 96-12-07, THE MECHANIC NOTICED THAT THE STOP PIN FOR THE IMPULSE COUPLING WAS MISSING. INSPECTED THE ACCESSORY SECTION AND FOUND THE PIN WEDGED BETWEEN THE CRANK CASE AND A GEAR. REMOVED THE PIN, NO FURTHER DAMAGE WAS FOUND.

Parts most often named Trunnion (3) · Stud (3) · Fitting (2) · Bolt (2)

NOSE GEAR RETRACTED ON LANDING. FOUND BOLT PN 401-421 (AN6-41A) LOOSE WHERE NOSE GEAR MOUNT BOLTS TO BULKHEAD AT STA 49.5. THIS RELEAVED DOWNLOCK LINK OVER CENTER POSITION. BOLTS SHOULD BE CHECKED EACH 500 HRS. (K)

(AUS) LT AND RT MAIN LANDING GEAR FORWARD TRUNNION WASHERS INCORRECT PARTS. CORRECT WASHERS HAVE A CHAMFER ON THE INTERNAL BORE WHICH ALLOWS CLEARANCE FOR THE TRUNNION SHOULDER RADIUS. THE WASHERS FITTED DID NOT HAVE THE CHAMFER. IN THIS CASE THE DAMAGE WAS MINIMAL. PERSONNEL/MAINTENANCE ERROR. UNAPPROVED PART.

NO LOG BOOKS WITH A/C. RT TACH: 1,993.5 HRS. HM-2,232.1 HRS. LEFT MAIN GEAR SEPARATED FROM A/C WHILE BEING TAXIED AFTER LANDING. FAILURE BELIEVED TO BE CAUSED BY REAR TRUNNION ASSY WITH CRACKS/BREAKS AT 3 OF 4 ATTACH AREAS. WHEN FINAL ATTACH AREA FAILED, THIS ALLOWED GEAR TO DAMAGE FORWARD ATTACH AND GEAR TO SEPARATE A/C. RECOMMEND FORWARD AND AFT TRUNNIONS BE INSPECTED AS MM REQUIRES DURING INSPECTION. (X)

Parts most often named Landing Gear (4) · Bolt (3) · Spring (3) · Bracket (3)

PILOT INSTRUCTOR AND STUDENT WERE FLYING THIS ACFT DOING TOUCH AND GOES. ON THE SECOND TOUCH AND GO THE NOSE GEAR WOULD NOT EXTEND. AFTER SEVERAL ATTEMPTS TO EXTEND THE NOSE GEAR BY THE PILOT, HE TRIED TO FREE FALL THE GEAR, BOTH MAINS EXTENDED BUT THE NOSE GEAR WOULD NOT.

(CAN) AFTER TOUCHDOWN, DURING ROLL OUT, THE NOSE GEAR RETRACTED CAUSING BOTH PROPELLERS TO STRIKE THE GROUND. DURING ASSESSMENT INSPECTION, LOWER TUNNEL BRACKET, PN 95554-00 WAS FOUND TO HAVE 4 RIVETS PULLED THROUGH CAUSING THE GEOMETRY TO CHANGE ON DOWN LINK ASSY. SB 1123B WAS BEING ACCOMPLISHED EVERY 50HRS ON THIS ACFT. SB 1123B DOES NOT REFERENCE THESE RIVETS. THESE RIVETS ARE EXTREMELY DIFFICULT TO INSPECT ON ACFT. WOULD RECOMMEND INSTALLING INSPECTION PANEL ACCESS IN BELLY.

(CAN) DURING A WALK AROUND, THE STUDENT PILOT NOTED THE SHIMMY DAMPENER AT AN AWKWARD ANGLE. THE SHAFT WAS BROKEN NEXT TO THE ROD END. NO OTHER VISIBLE DAMAGE WAS EVIDENT. THE PART WAS REPLACED.

Parts most often named Heater (3) · Line (3) · Regulator (2) · Pump (2)

(CAN) WHILE PERFORMING A PRESSURE DECAY TEST AS REQUIRED BY AD 2004-21-05 AN EXTENSIVE LEAK WAS DISCOVERED IN THE COMBUSTION TUBE. THE COMBUSTION TUBE WOULD NOT HOLD PRESSURE (6 PSIG) FOR MORE THAN A COUPLE OF SECONDS. UPON REMOVAL OF THE FORWARD DUCT A LARGE CRACK WAS DISCOVERED IN THE COMBUSTION TUBE. (TC# 20101217010)

PILOT REPORTED FUEL SMELL IN THE CABIN WHEN CABIN HEATER IS ON. FURTHER INVESTIGATION REVEALED A PIN HOLE CAUSED BY CORROSION IN THE CABIN HEATER FUEL LINE JUST AFT OF THE AFT SPAR CARRY THRU. (K)

WHILE PERFORMING AD 04-21-05, THE HEATER FAILED THE PRESSURE DECAY TEST. REMOVED UNIT AND FOUND CRACKS IN END OF COMBUSTION LINER. UNIT WAS REMOVED AND REPLACED WITH OVERHAULED UNIT. UNIT INSTALLED MAY 1998, AND CONTAINED NEW STYLE CERAMIC LINER.

Parts most often named Trunnion (10) · Bracket (3) · Fitting (1) · Nut Plate (1)

AIRCRAFT HAD A GEAR UNSAFE LIGHT DURING FLIGHT. FOUND RIGHT MAIN GEAR FORWARD TRUNNION ATTACH FITTING HARDWARE LOOSE. FURTHER INSPECTION REVEALED 4 BROKEN NUTPLATES.

DURING A VISUAL INSPECTION OF THE MLG, LEFT AFT TRUNNION MOUNTING PLATE WAS FOUND TO BE CRACKED AND BROKEN AT THE BEARING HOUSING AT THE 3 AND 9 O`CLOCK LOCATIONS, DURING CHECK OF OTHER TRUNION PLATES, FOUND MOUNTING BOLTS BELOW TORQUE AND MINOR HOLE ELONGATION, REPLACED ALL TRUNION MOUNTING PLATES WITH NEW.

DURING A VISUAL INSPECTION OF THE MLG, RT AFT TRUNNION MOUNTING PLATE PT WAS FOUND TO BE CRACKED ON THE STIFFENERS THAT FORM PART OF THE UPPER MOUNTING ARMS.