# Service difficulty reports: Lycoming O-540-F1B5

A list on [Lycoming O-540-F1B5](https://openairdocs.org/engine/lycoming-o-540-f1b5.md).

Newest first. General aviation reporting is voluntary.

Page 1 of 8 · 378 reports

- [SDR 2025FA0000661](https://openairdocs.org/sdr/2025FA0000661.md): Bracket · loose · Aug 8, 2025 · N829AK · Robsin R44 · Engine Starter
  > INSTALLED 3 DIFFERENT HARTZELL 149-12HT-H2 STARTERS (S/NS H-X112418, H-Z112422 & H-Z050870) BETWEEN 03/28/2025 AND 07/24/2025 ON A ROBINSON R44. EACH FAILED IN THE SAME MANNER AT 105.19, 82.66 & 9.91 HOURS TIME IN SERVICE RESPECTIVELY. IN EACH CASE THE ST2405
- [SDR 2NVA202408210020](https://openairdocs.org/sdr/2NVA202408210020.md): Control Rod · deformed · Aug 18, 2024 · N740RH · Robsin R44 · Tail Rotor Control System
  > DURING ATTEMPTED ROTOR ENGAGEMENT FOLLOWING ENGINE START, TAIL ROTOR PEDALS DEFLECTED FULL LEFT. ENGINE WAS IMMEDIATELY SHUT DOWN AFTER LESS THAN 45 DEGREES OF ROTOR MOVEMENT. INSPECTION REVEALED CONTACT BETWEEN AFT FLEX PLATE AND TAIL ROTOR CONTROL ROD. FURTH
- [SDR 2NVA202407090010](https://openairdocs.org/sdr/2NVA202407090010.md): Intake Valve · failed · Jul 9, 2024 · N328SS · Robsin R44 · Reciprocating Engine Cylinder Section
  > ABOUT 30 MINUTES INTO A TOUR, PILOT HEARD A SOUND AND EXPERIENCED LOSS OF POWER AND HIGH MANIFOLD PRESSURE. INITIATED POWER ON LANDING ON AN ADJACENT OPEN FIELD. VISUAL INSPECTION REVEALED OIL LEAK NEAR CYLINDER # 6. UPON REMOVAL OF VALVE COVER A BROKEN OFF VA
- [SDR 8HBR20240520062](https://openairdocs.org/sdr/8HBR20240520062.md): Ignition Unit · failed · May 19, 2024 · N4056V · Robsin R44 · Ignition System
  > PILOTS REPORTED A ROUGH ENGINE RUNNING ON THE LEFT IGNITION UNIT (EIS). IT WAS DETERMINED THE EIS UNIT HAS FAILED. THIS IS THE SECOND EIS IGNITION UNIT TO FAIL ON THIS AIRCRAFT.
- [SDR YV3R2023120100590](https://openairdocs.org/sdr/YV3R2023120100590.md): Dual Tachometer · defective · Nov 11, 2023 · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-5 ENGINE NEEDLE WAS OVERREADING 2%.
- [SDR 2NVA202311010001](https://openairdocs.org/sdr/2NVA202311010001.md): Intake Valve · damaged · Oct 28, 2023 · N328SS · Robsin R44 · Reciprocating Engine Cylinder Section
  > PILOT IDENTIFIED HIGH MANIFOLD PRESSURE REQUIRED AFTER TAKE OFF AND PERFORMED A PRE CAUTIONARY LANDING OFF AIRPORT. INSPECTION REVEALED A WET SPARK PLUG ON CYLINDER # 6. AFTER REMOVAL OF THE VALVE COVER, A BROKEN INTAKE VALVE TIP WAS DISCOVERED. NEW STYLE ROTA
- [SDR YV3R2023120100588](https://openairdocs.org/sdr/YV3R2023120100588.md): Governor · defective · Oct 5, 2023 · Robsin R44 · Engine (Reciprocating)
  > CUSTOMER REPORTED GOVERNOR ASSEMBLY P/N: B247-9 WAS INOPERATIVE.
- [SDR YV3R2023071000575](https://openairdocs.org/sdr/YV3R2023071000575.md): Clutch · faulty · May 30, 2023 · Robsin R44 · Main Rotor Drive System
  > CUSTOMER REPORTED HEAVY YAW MOVEMENTS WITH LOUD NOISES, C018-4 CLUTCH ASSEMBLY HAS ALUMINUM AND STEEL PARTICLES IN OIL.
- [SDR YV3R2023061400571](https://openairdocs.org/sdr/YV3R2023061400571.md): Switch · defective · May 19, 2023 · Robsin R44 · Main Rotor Drive System
  > CUSTOMER REPORTED SWITCHES ASSEMBLY P/N: C053-2 HAS LOOSE CONNECTIONS.
- [SDR YV3R2023061500572](https://openairdocs.org/sdr/YV3R2023061500572.md): Governor · defective · May 19, 2023 · Robsin R44 · Standard Practices/Structures
  > CUSTOMER REPORTED GOVERNOR ASSEMBLY P/N: B247-5 HAS POSSIBLE FRICTION LOSS AT ARM.
- [SDR YV3R2023061400570](https://openairdocs.org/sdr/YV3R2023061400570.md): Shield · cracked · May 18, 2023 · Robsin R44 · Engine Exhaust System
  > CUSTOMER REPORTED SHIELD ASSEMBLY P/N: D314-1 WAS FOUND CRACKED.
- [SDR YV3R2023042700560](https://openairdocs.org/sdr/YV3R2023042700560.md): Timer · defective · Apr 12, 2023 · Robsin R44 · Fuel Flow Sensor
  > CUSTOMER REPORTED TIME DELAY ASSEMBLY, LOW FUEL P/N: G655-1 LOW FUEL INDICATION INOPERATIVE.
- [SDR YV3R2023042700558](https://openairdocs.org/sdr/YV3R2023042700558.md): Dual Tachometer · defective · Apr 11, 2023 · N7102Z · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER P/N: C792-5 NEEDLES GET STUCK BETWEEN 68% - 90%.
- [SDR YV3R2022092300540](https://openairdocs.org/sdr/YV3R2022092300540.md): Governor · defective · Sep 15, 2022 · Robsin R44 · Engine Indicating System
  > CUSTOMER REPORTED GOVERNOR ASSEMBLY P/N: B247-5 ARM FRICTION WAS LOW.
- [SDR YV3R2022091400536](https://openairdocs.org/sdr/YV3R2022091400536.md): Governor · faulted · Aug 24, 2022 · Robsin R44 · Engine RPM Indicating System
  > CUSTOMER REPORTED GOVERNOR ASSEMBLY P/N: B247-5 ARM FRICTION WAS HIGH.
- [SDR 2022FA0000442](https://openairdocs.org/sdr/2022FA0000442.md): Intake Valve · burned · May 19, 2022 · N41LY · Robsin R44 · Reciprocating Engine Cylinder Section
  > LOW CYLINDER COMPRESSIONS WERE NOTED AT ANNUAL FOR AN ENGINE THAT WAS REPAIRED BY LYCOMING ONLY 180 HRS PRIOR TO CURRENT INSPECTION. BORESCOPE REVEALED BURNED INTAKE VALVES. CRANKSHAFT EXPANSION PLUG HAD A SUNSTANTIAL OIL LEAK AND CRANKSHAFT SEAL WAS LOOSE IN
- [SDR 2022FA0000523](https://openairdocs.org/sdr/2022FA0000523.md): Exhaust Valve · broken · Mar 22, 2022 · N7197V · Robsin R44 · Reciprocating Engine Cylinder Section
  > DURING CRUISE FLIGHT ENGINE BEGAN TO RUN ROUGH AND AN INCREASED POWER SETTING WAS REQUIRED TO MAINTAIN LEVEL FLIGHT. THE HELICOPTER IMMEDIATELY RETURNED TO THE HELIPAD AND MADE A NORMAL LANDING. BORE SCOPE INSPECTION REVEALED THAT THE #3 CYLINDER EXHAUST VALVE
- [SDR YV3R2022021000516](https://openairdocs.org/sdr/YV3R2022021000516.md): None · none · Jan 25, 2022 · N988DC · Robsin R22 · Fuel Quantity Sensor
  > CUSTOMER REPORTED FUEL SENDER (LEVEL) P/N: D252-1 CAUSED ERRATIC READINGS ON GAUGE ASSEMBLY.
- [SDR YV3R2022011000506](https://openairdocs.org/sdr/YV3R2022011000506.md): None · none · Dec 14, 2021 · Robsin R22 · Engine RPM Indicating System
  > GOVERNOR CONTROLLER P/N: D278-1 UNRESPONSIVE DURING AUTOROTATION RECOVERY TRAINING.
- [SDR YV3R2021110900501](https://openairdocs.org/sdr/YV3R2021110900501.md): None · none · Nov 2, 2021 · N161WP · Robsin R22 · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-1 COLUMN SWITCH FAILED.
- [SDR YV3R2021110900500](https://openairdocs.org/sdr/YV3R2021110900500.md): Collector · cracked · Oct 20, 2021 · Robsin R22 · Engine Exhaust System
  > CUSTOMER REPORTED COLLECTOR P/N: C169-5 EXHAUST (LH) WAS CRACKED.
- [SDR YV3R2021082800480](https://openairdocs.org/sdr/YV3R2021082800480.md): Actuator · defective · Aug 13, 2021 · Robsin R44 · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-1 WILL NOT DISENGAGE DURING SWITCH SPRING TEST METHOD 1.
- [SDR YV3R2021081100479](https://openairdocs.org/sdr/YV3R2021081100479.md): Governor · defective · Jul 29, 2021 · Robsin R44 · Engine (Reciprocating)
  > CUSTOMER REPORTED GOVERNOR ASSEMBLY P/N: B247-5 WAS UNSERVICEABLE.
- [SDR YV3R2021081000475](https://openairdocs.org/sdr/YV3R2021081000475.md): Gauge · faulted · Jul 22, 2021 · Robsin R44 · Engine Air Intake System
  > CUSTOMER REPORTED CARBURETOR AIR TEMPERATURE GAUGE P/N: C604-8 WAS FAULTY.
- [SDR YV3R2021081000476](https://openairdocs.org/sdr/YV3R2021081000476.md): Gauge · defective · Jul 22, 2021 · Robsin R44 · Manifold Pressure (MP) Indicating
  > CUSTOMER REPORTED MANIFOLD PRESSURE GAGE P/N: A600-4 WAS FAULTY.
- [SDR YV3R2021070700468](https://openairdocs.org/sdr/YV3R2021070700468.md): Dual Tachometer · defective · Jun 29, 2021 · N46SG · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER P/N: C792-4 ROTOR NEEDLE WAS INTERMITTENT, AND THEN FAIL COMPLETELY.
- [SDR YV3R2021062200463](https://openairdocs.org/sdr/YV3R2021062200463.md): Actuator · defective · Jun 8, 2021 · Robsin R44 · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-1 DID NOT COLLAPSE A COLUMN.
- [SDR YV3R2021060900461](https://openairdocs.org/sdr/YV3R2021060900461.md): Dual Tachometer · defective · Jun 1, 2021 · N715SG · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER P/N: C792-4 ENGINE NEEDLE PEGS WITH POWER APPLIED.
- [SDR YV3R2021052800453](https://openairdocs.org/sdr/YV3R2021052800453.md): Switch · defective · May 11, 2021 · N8330G · Robsin R22BETA · Electrical Power System
  > CUSTOMER REPORTED SWITCHES ASSEMBLY P/N: C053-2 HAD A FAULTY SWITCH.
- [SDR 2021FA0000119](https://openairdocs.org/sdr/2021FA0000119.md): Gauge · defective · Apr 20, 2021 · N988DC · Robsin R44 · Manifold Pressure (MP) Indicating
  > CUSTOMER REPORTED MANIFOLD PRESSURE GAGE P/N: A600-4 WILL NOT DISPLAY CORRECT PRESSURE.
- [SDR YV3R2021043000452](https://openairdocs.org/sdr/YV3R2021043000452.md): Gauge · defective · Apr 20, 2021 · N988DC · Robsin R44 · Manifold Pressure (MP) Indicating
  > REVISED UNIQUE CONTROL #: CUSTOMER REPORTED MANIFOLD PRESSURE GAGE P/N: A600-4 WILL NOT DISPLAY CORRECT PRESSURE.
- [SDR 2021FA0000162](https://openairdocs.org/sdr/2021FA0000162.md): Cylinder Head · cracked · Apr 4, 2021 · N306M · Reciprocating Engine Cylinder Section
  > DURING FLIGHT, THE PILOT NOTICED A 20 KNOT LOSS UNDER MAXIMUM CONTINUOUS POWER. UPON LANDING AND INSPECTION, OIL SPRAY WAS FOUND ON RIGHT SIDE OF ENGINE AND FIREWALL. OIL QUANTITY, PRESSURE, AND TEMPERATURE INDICATORS WERE IN THE GREEN. OIL CONSUMPTION WENT FR
- [SDR 2021FA0000163](https://openairdocs.org/sdr/2021FA0000163.md): Cylinder Head · cracked · Apr 4, 2021 · N306MB · Reciprocating Engine Cylinder Section
  > DURING FLIGHT, THE PILOT NOTICED A 20 KNOT LOSS UNDER MAXIMUM CONTINUOUS POWER. UPON LANDING AND INSPECTION, OIL SPRAY WAS FOUND ON RIGHT SIDE OF ENGINE AND FIREWALL. OIL QUANTITY, PRESSURE, AND TEMPERATURE INDICATORS WERE IN THE GREEN. OIL CONSUMPTION WENT FR
- [SDR YV3R2021031300447](https://openairdocs.org/sdr/YV3R2021031300447.md): Motor · defective · Mar 5, 2021 · Robsin R44 · Main Rotor Drive System
  > CUSTOMER REPORTED GEARMOTOR ASSEMBLY P/N: D276-1 OPERATION TOO SLOW.
- [SDR YV3R2021031200444](https://openairdocs.org/sdr/YV3R2021031200444.md): Motor · defective · Mar 1, 2021 · Robsin R44 · Main Rotor Drive System
  > CUSTOMER REPORTED GEARMOTOR ASSEMBLY P/N: D276-3 WAS INTERMITTENT IN OPERATION.
- [SDR YV3R2021031200445](https://openairdocs.org/sdr/YV3R2021031200445.md): Gauge · defective · Mar 1, 2021 · Robsin R44 · Manifold Pressure (MP) Indicating
  > CUSTOMER REPORTED MANIFOLD ABSOLUTE PRESSURE GAGE (M.A.P) P/N: A600-4 WAS INTERMITTENT IN OPERATION.
- [SDR YV3R2021022200435](https://openairdocs.org/sdr/YV3R2021022200435.md): Transmitter · defective · Feb 16, 2021 · Robsin R44 · Fuel Quantity Sensor
  > CUSTOMER REPORTED SENDER-FUEL LEVEL PN: D252-1 WAS READING INCORRECTLY.
- [SDR YV3R2021022200436](https://openairdocs.org/sdr/YV3R2021022200436.md): Gauge · defective · Feb 16, 2021 · Robsin R44 · Manifold Pressure (MP) Indicating
  > CUSTOMER REPORTED MANIFOLD ABSOLUTE PRESSURE GAGE (M.A.P) P/N: A600-4 NEEDLE INDICATING INCORRECTLY.
- [SDR YV3R2021022200437](https://openairdocs.org/sdr/YV3R2021022200437.md): Gauge · defective · Feb 16, 2021 · Robsin R44 · Manifold Pressure (MP) Indicating
  > CUSTOMER REPORTED MANIFOLD ABSOLUTE PRESSURE GAGE (M.A.P) P/N: A600-4 INDICATING NEEDLE STUCK.
- [SDR YV3R2021030300440](https://openairdocs.org/sdr/YV3R2021030300440.md): Dual Tachometer · defective · Feb 16, 2021 · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-5 ENGINE RPM INDICATION WAS IRREGULAR.
- [SDR YV3R2021022200434](https://openairdocs.org/sdr/YV3R2021022200434.md): Governor · defective · Feb 10, 2021 · N888SN · Robsin R44 · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY (GOVERNOR) PN: D278-1 WAS INOPERATIVE WHEN TURNED ON ABOVE 80%.
- [SDR YV3R2021022200433](https://openairdocs.org/sdr/YV3R2021022200433.md): Dual Tachometer · defective · Feb 9, 2021 · N72SL · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY PN: C792-4 ROTOR NEEDLE WAS INOPERATIVE.
- [SDR 2021FA0000030](https://openairdocs.org/sdr/2021FA0000030.md): Governor · failed · Feb 3, 2021 · N888SN · Robsin R44 · Engine Controls
  > DURING AIRCRAFT RUN-UP PROCEDURES PILOT ENGAGED GOVERNOR SWITCH INCREASED THROTTLE TO 832% FOR GOVERNOR TO TAKE OVER. GOVERNOR FAILED TO ENGAGE, AIRCRAFT SHUT DOWN NORMALLY. MECHANIC PERFORMED TROUBLESHOOTING PROCEDURES FOUND GOVERNOR CONTROLLER PN D278-1 TO
- [SDR YV3R2021020400431](https://openairdocs.org/sdr/YV3R2021020400431.md): Dual Tachometer · defective · Feb 1, 2021 · N34TB · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-4 WAS INDICATING ERRATIC.
- [SDR YV3R2021020400430](https://openairdocs.org/sdr/YV3R2021020400430.md): Indicator · defective · Jan 20, 2021 · Robsin R44RAVENII · Attitude Gyro and Indicating System
  > CUSTOMER REPORTED ATTITUDE INDICATOR P/N: B823-12 WAS READING INACCURATELY.
- [SDR YV3R2021011100419](https://openairdocs.org/sdr/YV3R2021011100419.md): Shield · cracked · Jan 7, 2021 · Robsin R44 · Engine Exhaust System
  > CUSTOMER REPORTED EXHAUST SHIELD ASSEMBLY P/N: D314-1 WAS CRACKED.
- [SDR YV3R2021012000423](https://openairdocs.org/sdr/YV3R2021012000423.md): Dual Tachometer · defective · Jan 7, 2021 · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: ROTOR NEEDLE WAS INTERMITTENT.
- [SDR YV3R2021012000421](https://openairdocs.org/sdr/YV3R2021012000421.md): Dual Tachometer · defective · Jan 6, 2021 · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-4 ROTOR NEEDLE GOES FULL SCALE.
- [SDR YV3R2021010500412](https://openairdocs.org/sdr/YV3R2021010500412.md): Dual Tachometer · defective · Dec 18, 2020 · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-4 ROTOR NEEDLE WAS UNSERVICEABLE.
- [SDR YV3R2021010700414](https://openairdocs.org/sdr/YV3R2021010700414.md): Dual Tachometer · reads low · Dec 18, 2020 · Robsin R44 · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C972-4 RPM NEEDLE READS LOW (INACCURATE).

Next page: https://openairdocs.org/engine/lycoming-o-540-f1b5/reports.md?page=2

## 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 = 'O540F1B5'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/engine/lycoming-o-540-f1b5/reports

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