# Service difficulty reports: Lycoming AEIO-540 series

A list on [Lycoming AEIO-540 series](https://openairdocs.org/engine/lycoming-aeio-540-series.md).

Newest first. General aviation reporting is voluntary.

- [SDR 2026FA0000637](https://openairdocs.org/sdr/2026FA0000637.md): Servo · faulted · Aug 13, 2026 · N3041B · Piper PA32RT300 · Engine Fuel Distribution
  > PILOT REPORTED THE FUEL PRESSURE PEGGED MAX PRESSURE CAUSING THE GAUGE TO BECOME INOP. IT WAS REPLACED AND AGAIN THE GAUGE WENT TO MAX & BECAME INOP, THE FUEL FLOW AT FULL THROTTLE NOW EXCEEDS 30GPH INDICATED WHERE IT USED TO BE 28GPH & ALL THE CYLINDER HEAD T
- [SDR 2026FA0000344](https://openairdocs.org/sdr/2026FA0000344.md): Thrust Button · melted · May 9, 2026 · Reciprocating Engine Cylinder Section
  > UPON INSPECTION AFTER MAJOR ENGINE OVERHAUL, IT WAS DISCOVERED THAT ALL ROCKER SHAFT THURST BUTTONS HAD EITHER PARTIALLY OR COMPLETELY MELTED. MELTED PLASTIC DEBRIS WAS DISCOVERED IN THE ROCKER COVERS AND OIL SUMP SCREEN. DEFECTIVE THRUST BUTTONS WERE REMOVED
- [SDR 2015FA0000194](https://openairdocs.org/sdr/2015FA0000194.md): Relay · faulty · May 4, 2015 · N706M · Found FBA2C1 · Rudder Tab Control System
  > ON CLIMBOUT WHILE MANUALLY DRIVING THE RUDDER TRIM WITH THE RUDDER TRIM SWITCH, THE RUDDER TRIM "RAN AWAY" FULL RT. PILOT COULD DRIVE IT BACK TO THE LT WITH THE TRIM SWITCH, BUT WHEN HE TRIED ADDING RT RUDDER TRIM IT WOULD KEEP DRIVING TO FULL DEFLECTION RT.
- [SDR 2011FA0000535](https://openairdocs.org/sdr/2011FA0000535.md): Control Cable · failed · Aug 19, 2011 · N867AF · Grob G120A · Mixture Control
  > PILOT REPORTED DURING FLIGHT HE EXPERIENCED A TOTAL LOSS OF MIXTURE CONTROL. INVESTIGATION REVEALED THE MIXTURE CONTROL CABLE HAD BROKEN AT THE CONTROL IN THE CABIN. NO RECOMMENDATIONS AT THIS TIME.
- [SDR CA100824004](https://openairdocs.org/sdr/CA100824004.md): Handle · binding · Aug 24, 2010 · Grob G120A · Landing Gear Selector
  > INSTRUCTOR AND STUDENT WERE CONDUCTING THEIR 11TH TAKEOFF WHILE PRACTICING LOCAL CIRCUITS WHEN THE STUDENT DISCOVERED THAT THE LANDING GEAR HANDLE COULD NOT BE SELECTED UP FOR THE CLIMB-OUT. THE INSTRUCTOR TOOK CONTROL OF THE ACFT AND VERIFED THAT THE HANDLE
- [SDR 2008FA0000495](https://openairdocs.org/sdr/2008FA0000495.md): Fuel Sys · malfunctioned · May 25, 2008 · N22MW · Rhnflu EA300L · Aircraft Fuel System
  > APPROX 9 GALLONS OF FUEL IN CENTER TANK BECAME INACCESSIBLE DURING FLT, PRECAUTIONARY LANDING. AFTER DEPARTING USING CENTER TANK FUEL FOR A 120 MILE FERRY FLIGHT, SWITCHED TO THE WING TANKS FOR THE PREPONDERANCE OF THE TRIP. NEARING THE DESTINATION WITH T
- [SDR 2007FA0000397](https://openairdocs.org/sdr/2007FA0000397.md): Bearing · broken · Mar 31, 2007 · N7178P · Piper PA24250 · Main Landing Gear
  > BEARING ROD END BROKEN AT THREAD EXP BEARING (452377) CONDUIT BENT. CONTROL ASSY (455180).
- [SDR 2006FA0001183](https://openairdocs.org/sdr/2006FA0001183.md): Bracket · cracked · Dec 8, 2006 · N497AF · Extra EA300 · Flight Compartment Equipment
  > DURING A ROUTINE INSPECTION IT WAS NOTICED THE 76201.113 TOUNGE BRACKETS LT AND RT WHICH ATTACH THE REAR SEAT BACKREST TO THE LOWER SEAT ASSEMBLY WERE CRACKED THRU THE BOLT HOLES ATTACHING TO THE BACKREST. FURTHER CLOSE EXAMINATION (REMOVED UPHOLSTERY)OF THE R
- [SDR 2007FA0000003](https://openairdocs.org/sdr/2007FA0000003.md): Pump · out of limits · Nov 10, 2006 · N864AF · Grob G120A · Pneumatic System
  > PILOT REPORTED SUCTION INDICATOR WAS BELOW LIMITS, AC RETURNE TO BASE. UPON TROUBLESHOOTING, THE MECHANIC REMOVED THE AIR PUMP AND NOTICED THE SHAFT WAS VERY EASY TO ROTATE, HAD NO RESISTANCE TO IT. NO PROBABLE CAUSE OR RECOMMENDATIONS AT THIS TIME. (K)
- [SDR 2007FA0000007](https://openairdocs.org/sdr/2007FA0000007.md): Pump · worn · Oct 30, 2006 · N865AF · Grob G120A · Vacuum Distribution System
  > DURING FLIGHT SUCTION PRESSURE READING DROPPED TO ZERO, DURING FURTHER TROUBLESHOOTING, TECH FOUND THE ENGINE DRIVEN AIR PUMP WAS NOT PRODUCTING ENOUGH SUCTION. PROBABLE CAUSE COULD BE FROM PISTION WEARING INSIDE OF PUMP. RECOMMENDATION AT THIS TIME IS FOR T
- [SDR 2007FA0000006](https://openairdocs.org/sdr/2007FA0000006.md): Shaft · broken · Sep 26, 2006 · N865AF · Grob G120A · Vacuum System
  > DURING ENGINE START, SUCTION PRESSURE WAS READING ZERO, DURING FURTHER TROUBLESHOOTING, TECH FOUND THE ENGINE DRIVEN DRIVEN DRY AIR PUMP HAD A BROKEN SHAFT. PROBABLE CAUSE COULD BE FROM VIBRATION OR HARD START. NO RECOMMENDATION AT THIS TIME. (K)
- [SDR 2007FA0000005](https://openairdocs.org/sdr/2007FA0000005.md): Pump · worn · Sep 22, 2006 · N862AF · Grob G120A · Vacuum System
  > DURING FLIGHT SUCTION PRESSURE READING DROPPED TO ZERO, DURING FURTHER TROUBLESHOOTING TECHICIAN FOUND THE ENGINE DRIVEN DRY AIR PUMP SHAFT HAD BROKEN. PROBABLE CAUSE COULD BE FROM ENGINE VIBRATION OR POOR PARTS. RECOMMENDATION AT THIS TIME IS FOR THE MFG T
- [SDR SJ3R020511](https://openairdocs.org/sdr/SJ3R020511.md): Hub · damaged · Aug 9, 2006 · Inland S300 · Propeller Hub Section
  > PROPELLER MOUNTING FLANGE HAS EXCESSIVE FRETTING DAMAGE. HUB IS SCRAP.
- [SDR 2005FA0001579](https://openairdocs.org/sdr/2005FA0001579.md): Longeron · cracked · Dec 14, 2005 · N78EX · Rhnflu EA300L · Fuselage Main, Longeron/Stringer
  > DURING ROUTINE 1,000 HR INSPECTION CRACKS WERE FOUND IN THE UPPER LONGERON AT THE HORIZONTAL STABILIZER ATTACHMENT, THESE WERE VERIFIED USING A FLUORESCENT DYE CHECK PENETRANT METHOD, CRACKS WERE ALSO FOUND IN THE VERTICAL TUBE SUPPORTING FORCES FROM THE TAIL
- [SDR 2005FA0001526](https://openairdocs.org/sdr/2005FA0001526.md): Canopy · departed · Nov 3, 2005 · N114RM · Ayres S2C · Flight Compartment Windows
  > CANOPY ASSEMBLY PN S2C503, DEPARTED AIRCRAFT DURING NORMAL FLIGHT ATTITUDE AND CRUISE SPEED. NO APPARENT COMPONENT FAILURE NOTED ON AIRCRAFT COCKPIT STRUCTURE OR CANOPY RETAINING COMPONENTS. SINCE CANOPY ASSEMBLY WAS NOT RECOVERED. NO PROBABLE CAUSE FOR SEP
- [SDR X6PA200500005](https://openairdocs.org/sdr/X6PA200500005.md): Crankcase · cracked · Jun 10, 2005 · N6934J · Piper PA32R300 · Engine (Reciprocating)
  > ENGINE INSPECTED DUE TO AN OIL LEAK. DURING THE INSPECTION THE RIGHT CRANK CASE WAS FOUND CRACKED SIX INCHES IN LENGTH AROUND THE BOTTOM PERIMETER OF THE NR 3 CYLINDER. ENGINE TTSMOH 1028.22
- [SDR 2005FA0000801](https://openairdocs.org/sdr/2005FA0000801.md): Plate · debonded · May 13, 2005 · N867AF · Grob G120A · Rudder, Spar/Rib
  > DURING FLEET-WIDE INSPECTION OF AIRCRAFT, TECH FOUND EXCESSIVE MOVEMENT BETWEEN RUDDER AND RUDDER LEVER ASSY. FURTHER INSPECTION SHOWED DISBONDING BETWEEN THE RUDDER SPAR AND THE RUDDER LEVER ASSY SPACER PLATE. PROBABLE CAUSE APPEARS TO BE EXCESSIVE FLEXING
- [SDR 2005FA0000112](https://openairdocs.org/sdr/2005FA0000112.md): Ignition Switch · inoperative · Jan 18, 2005 · N865AF · Grob G120A · Ignition Switching
  > PILOT REPORTED STARTER WOULD NOT ENGAGE, AFTER FURTHER INVESTIGATION FOUND IGNITION SWITCH WAS BAD. NO PROBABLE CAUSE OR RECOMMENDATIONS AT THIS TIME. (K)
- [SDR 2005FA0001122](https://openairdocs.org/sdr/2005FA0001122.md): Bearing · failed · Nov 4, 2004 · N864AF · Grob G120A · Main Landing Gear
  > DURING INSPECTION OF MAIN LANDING GEAR, DISCOVERED EXCESSIVE FORE AND AFT PLAY IN RT MLG LEG. RT MAIN LEG COULD MOVE FORE AND AFT 4MM OR MORE. GEAR LEG WAS REMOVED. INSPECTION OF THE AFT TRUNION ASSY REVEALED THAT THE BEARING HAD FAILED AND HAD EXCESSIVE PL
- [SDR 2004FA0000717](https://openairdocs.org/sdr/2004FA0000717.md): Ignition Switch · intermittent · Jul 27, 2004 · N864AF · Grob G120A · Ignition Switching
  > AFTER INSTALLING IGNITION SWITCH, THE MECHANIC NOTICE THE SWITCH WAS HARD TO PUSH IN AND INTERMITTENT AT THE START POSITION. NO PROBABLE CAUSE OR RECOMMENDATIONS AT THIS TIME.
- [SDR 2004FA0000720](https://openairdocs.org/sdr/2004FA0000720.md): Starter · intermittent · Jul 27, 2004 · N864AF · Grob G120A · Engine Starter
  > PILOT REPORTED STARTER WOULD NOT ENGAGE, PROBABLE CAUSE AT THIS TIME UNKNOWN.

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
SELECT sdr_id, difficulty_date, n_number, aircraft_make, aircraft_model, part_name, part_condition, jasc_code, discrepancy
FROM 'https://openairdocs.org/data/latest/faa_service_difficulty_report.parquet'
WHERE engine_model_key = 'AEIO540'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/engine/lycoming-aeio-540-series/reports

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