# Service difficulty reports: Lycoming O-360-A4M

A list on [Lycoming O-360-A4M](https://openairdocs.org/engine/lycoming-o-360-a4m.md).

Newest first. General aviation reporting is voluntary.

Page 1 of 12 · 559 reports

- [SDR 2026FA0000604](https://openairdocs.org/sdr/2026FA0000604.md): Carburetor · faulted · Jul 2, 2026 · N172KJ · Cessna 172N · Fuel Control/Reciprocating Engines
  > AFTER ONLY 360.49 TACH HOURS IN SERVICE FOUND THROTTLE GETTING STUCK BEFORE FULL THROTTLE STOP. SUSPECTED ACCELERATOR PUMP PLUNGER GETTING STUCK NOT ALLOWING THROTTLE ARM TO HIT FULL THROTTLE STOP.
- [SDR 2026FA0000201](https://openairdocs.org/sdr/2026FA0000201.md): Impulse Coupling · defective · Mar 20, 2026 · N314AV · Cessna 172M · Magneto/Distributor
  > MAGNETO PULLED DURING ROUTINE MAINTENANCE TO CHECK FOR THE PRESENCE OF A CHAMPION MANUFACTURED IMPULSE COUPLING. ONE WAS FOUND INSTALLED AND THUS REMOVED FOR REPLACEMENT WITH A NEW ES3163 IMPULSE COUPLING. AFTER REMOVAL OF THE OLD IMPULSE COUPLING, I DISASSEM
- [SDR 2025FA0000633](https://openairdocs.org/sdr/2025FA0000633.md): Cylinder Head · cracked · Sep 9, 2025 · N99040 · Cessna 172P · Reciprocating Engine Cylinder Section
  > NR 4 CYLINDER HEAD CRACKED ACROSS COOLING FINS IN FLIGHT. CREW NOTICED LOSS OF POWER/SHUDDER.
- [SDR 2025FA0000253](https://openairdocs.org/sdr/2025FA0000253.md): Retaining Ring · defective · Apr 8, 2025 · N43753 · Piper PA28181 · Nose/Tail Landing Gear
  > DURING THE INSTALLATION OF THE RETAINING RING IT IMMEDIATELY BROKE. SENT THE STRUT TO ANOTHER SHOP THEY ATTEMPTED AND BROKE 2 MORE. SPOKE WITH PIPER TECHNICIAN AND RECEIVED THIS AS A RESPONSE. "AS PER OUR PHONE CONVERSATION YESTERDAY REGARDING THE INSTALLATION
- [SDR 2025FA0000204](https://openairdocs.org/sdr/2025FA0000204.md): Carburetor · faulted · Nov 15, 2024 · N113SW · Piper PA28181 · Fuel Control/Reciprocating Engines
  > FARGO, ND (FAR): N113SW, P28A, FAR-FAR, DECLARED AN EMERGENCY DUE TO A ROUGH RUNNING ENGINE. ACFT RETURNED TO FAR ARPT, LANDED, AND TAXIED TO THE RAMP WITHOUT FURTHER INCIDENT. 11/15/2024 2238Z. OVERHAULED CARBURETOR INSTALLED ON NOVEMBER 8TH, 2024.
- [SDR 2024FA0000288](https://openairdocs.org/sdr/2024FA0000288.md): Bulkhead · cracked · Apr 4, 2024 · N644FT · Piper PA28181 · Propeller System
  > FWD SPINNER BULKHEAD DEVELOPED CRACKS NEAR BOLTS, OBSERVED THAT CRACKS CONTINUE TO DEVELP AFTER REPLACEMENT, AFTER ONLY A FEW HOURS IN SERVICE.
- [SDR 2024FA0000061](https://openairdocs.org/sdr/2024FA0000061.md): Rivet · loose · Jan 15, 2024 · N475TA · Magneto/Distributor
  > MAGNETO P/N 4371 S/N 22071298. LOOSE RIVETS FOUND ON IMPULSE COUPLING DURING 500 HOUR INSPECTION. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2024FA0000060](https://openairdocs.org/sdr/2024FA0000060.md): Rivet · loose · Jan 11, 2024 · N662A · Magneto/Distributor
  > MAGNETO P/N 4371 S/N 22070051. LOOSE RIVETS FOUND ON IMPULSE COUPLING DURING 500 HOUR INSPECTION. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2024FA0000059](https://openairdocs.org/sdr/2024FA0000059.md): Impulse Coupling · damaged · Dec 14, 2023 · N959G · Magneto/Distributor
  > MAGNETO P/N 4371 S/N 21030390. LOOSE RIVETS FOUND ON IMPULSE COUPLING DURING 500 HOUR INSPECTION. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2024FA0000058](https://openairdocs.org/sdr/2024FA0000058.md): Rivet · loose · Nov 9, 2023 · N348D · Magneto/Distributor
  > MAGNETO P/N 4371 S/N 22010949. LOOSE RIVETS FOUND ON IMPULSE COUPLING DURING 500 HOUR INSPECTION. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2024FA0000057](https://openairdocs.org/sdr/2024FA0000057.md): Rivet · loose · Oct 18, 2023 · N935G · Magneto/Distributor
  > MAGNETO P/N 4371 S/N 21091251. LOOSE RIVETS FOUND ON IMPULSE COUPLING DURING 500 HOUR INSPECTION. REPLACED IMPULE COUPLING WITH NEW.
- [SDR 2024FA0000055](https://openairdocs.org/sdr/2024FA0000055.md): Rivet · loose · Sep 13, 2023 · N792A · Magneto/Distributor
  > MAGNETO P/N 66GC20SFNN S/N 21080300. LOOSE RIVETS FOUND ON IMPULSE COUPLING DURING 500 HOUR INSPECTION. REPLACED IMPULE COUPLING WITH NEW.
- [SDR 2023FA0000528](https://openairdocs.org/sdr/2023FA0000528.md): Unknown · unknown · Sep 8, 2023 · N792A · Piper PA28181 · Ignition System
  > PILOT REPORTS THAT THE INITIAL MAGNETO CHECK, THE ENGINE WAS RUNNING ROUGH, ON SECOND MAGNETO CHECK ENGINE SMOOTH OUT. ON TAKE OFF THE ENGINE POWER FLUCTUATED AND AIRCRAFT DID NOT MAKE POWER. PILOT ABORTED TAKE-OFF. WE PERFORMED A VISUAL INSPECTION OF THE ENGI
- [SDR 2023FA0000494](https://openairdocs.org/sdr/2023FA0000494.md): Impulse Coupling · loose · Aug 18, 2023 · N151G · Magneto/Distributor
  > FOUND MAGNETO IMPULSE COUPLING RIVETS LOOSE AND REPLACED WITH NEW IMPULSE COUPLING.
- [SDR 2023FA0000493](https://openairdocs.org/sdr/2023FA0000493.md): Impulse Coupling · loose · Aug 10, 2023 · N147G · Magneto/Distributor
  > FOUND MAGNETO IMPULSE COUPLING RIVETS LOOSE AND REPLACED WITH NEW IMPULSE COUPLING.
- [SDR 2023FA0000491](https://openairdocs.org/sdr/2023FA0000491.md): Impulse Coupling · loose · Jul 6, 2023 · N412A · Magneto/Distributor
  > FOUND MAGNETO IMPULSE COUPLING RIVETS LOOSE AND REPLACED WITH NEW IMPULSE COUPLING.
- [SDR 2023FA0000492](https://openairdocs.org/sdr/2023FA0000492.md): Impulse Coupling · loose · Jul 6, 2023 · N219A · Magneto/Distributor
  > FOUND MAGNETO IMPULSE COUPLING RIVETS LOOSE AND REPLACED WITH NEW IMPULSE COUPLING.
- [SDR 2023FA0000490](https://openairdocs.org/sdr/2023FA0000490.md): Impulse Coupling · loose · Jun 30, 2023 · N991A · Magneto/Distributor
  > FOUND MAGNETO IMPULSE COUPLING RIVETS LOOSE AND REPLACED WITH NEW IMPULSE COUPLING.
- [SDR 2023FA0000210](https://openairdocs.org/sdr/2023FA0000210.md): Impulse Coupling · loose · Apr 7, 2023 · N386D · Ignition System
  > MAGNETO IMPULSE COUPLING RIVETS FOUND LOOSE, REPLACED COUPLING WITH NEW.
- [SDR 2023FA0000208](https://openairdocs.org/sdr/2023FA0000208.md): Impulse Coupling · loose · Apr 5, 2023 · N358G · Ignition System
  > MAGNETO IMPULSE COUPLING RIVETS FOUND LOOSE, REPLACED COUPLING WITH NEW.
- [SDR 2023FA0000197](https://openairdocs.org/sdr/2023FA0000197.md): Impulse Coupling · loose · Mar 15, 2023 · N449A · Ignition System
  > ENGINE LEFT MAGNETO IMPULSE COUPLING RIVETS FOUND BENT, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2023FA0000196](https://openairdocs.org/sdr/2023FA0000196.md): Impulse Coupling · loose · Mar 14, 2023 · N877G · Ignition System
  > ENGINE LEFT MAGNETO IMPULSE COUPLING RIVETS FOUND LOOSE, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2023FA0000191](https://openairdocs.org/sdr/2023FA0000191.md): Impulse Coupling · loose · Mar 13, 2023 · N394D · Ignition System
  > ENGINE LEFT MAGNETO IMPULSE COUPLING RIVETS FOUND BENT, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2023FA0000131](https://openairdocs.org/sdr/2023FA0000131.md): Impulse Coupling · defective · Mar 3, 2023 · N592K · Ignition System
  > MAGNETO IMPULSE COUPLING FOUND TO HAVE LOOSE RIVETS, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2023FA0000097](https://openairdocs.org/sdr/2023FA0000097.md): Battery Pack · mismanufactured · Feb 22, 2023 · N12492 · Cessna 172M · Emergency Locator Beacon
  > A NEW ARTEX ELT WITH A NEW BATTERY WAS INSTALLED IN THE AIRCRAFT ON 8/16 AND THE BATTERY PACK LABEL HAD A MANUFACTURE DATE OF 5/16 AND AN EXPIRATION DATE OF 10/23. UPON ROUTINE INSPECTION ON 2/23, THE BATTERY DID NOT HAVE ENOUGH ENERGY TO PASS ITS INTERNAL TES
- [SDR 2023FA0000339](https://openairdocs.org/sdr/2023FA0000339.md): Attach Bolt · loose · Feb 14, 2023 · N28AU · Piper PA28181 · Vertical Stabilizer
  > ALL 4 BOLTS HOLDING VERTICAL STABILIZER SPAR TO REAR BULKHEAD WERE LOOSE. I SAW BLACK ALUMINUM DUST AROUND THE LOWER TWO DURING A ROUTINE INSPECTION. I REMOVED THE BOLTS AND DID NOT FIND SIGNIFICANT WEAR ON THE STRUCTURES. THE NUTS HAD TORQUE STRIPE ON THEM, C
- [SDR 2023FA0000192](https://openairdocs.org/sdr/2023FA0000192.md): Impulse Coupling · loose · Feb 1, 2023 · N485A · Ignition System
  > ENGINE LEFT MAGNETO IMPULSE COUPLING RIVETS FOUND LOOSE, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2023FA0000056](https://openairdocs.org/sdr/2023FA0000056.md): Impulse Coupling · defective · Jan 24, 2023 · N598A · Magneto/Distributor
  > ENGINE LEFT MAGNETO MODEL 4371 S.N. 21090440, FOUND IMPULSE COUPLING RIVETS LOOSE. REPLACED IMPULSE COUPLING
- [SDR 2023FA0000054](https://openairdocs.org/sdr/2023FA0000054.md): Rotor Shaft · defective · Jan 4, 2023 · N869G · Magneto/Distributor
  > ENGINE RIGHT MAGNETO MODEL 4370 S.N. 21011028, FOUND ROTOR SHAFT SHEARED AT BALL BEARING. REPLACED MAGNETO WITH NEW.
- [SDR 2023FA0000053](https://openairdocs.org/sdr/2023FA0000053.md): Impulse Coupling · defective · Dec 30, 2022 · N952A · Magneto/Distributor
  > ENGINE LEFT MAGNETO MODEL 4371 S.N. 21080467, FOUND IMPULSE COUPLING P/N M3163 TO HAVE LOOSE RIVETS. REPLACED WITH NEW.
- [SDR 2023FA0000195](https://openairdocs.org/sdr/2023FA0000195.md): Impulse Coupling · loose · Dec 9, 2022 · N676A · Ignition System
  > ENGINE LEFT MAGNETO IMPULSE COUPLING RIVETS FOUND LOOSE, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000749](https://openairdocs.org/sdr/2022FA0000749.md): Impulse Coupling · loose · Dec 6, 2022 · N710A · Magneto/Distributor
  > DURING 500HR MAGNETO INSPECTION FOUND MAG 4371, S.N. 18071029 IMPULSE COUPLING RIVETS LOOSE. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000748](https://openairdocs.org/sdr/2022FA0000748.md): Impulse Coupling · loose · Dec 1, 2022 · N861P · Magneto/Distributor
  > DURING 500HR MAGNETO INSPECTION FOUND MAG 4371, S.N. 21080836 IMPULSE COUPLING RIVETS LOOSE. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000747](https://openairdocs.org/sdr/2022FA0000747.md): Impulse Coupling · loose · Nov 30, 2022 · N547K · Magneto/Distributor
  > DURING 500HR MAGNETO INSPECTION FOUND MAG 4371, S.N. 19080251 IMPULSE COUPLING RIVETS LOOSE. REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2023FA0000194](https://openairdocs.org/sdr/2023FA0000194.md): Impulse Coupling · loose · Nov 22, 2022 · N845G · Ignition System
  > ENGINE LEFT MAGNETO IMPULSE COUPLING RIVETS FOUND LOOSE, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000709](https://openairdocs.org/sdr/2022FA0000709.md): Impulse Coupling · loose · Nov 18, 2022 · N684A · Magneto/Distributor
  > SLICK MAG P/N 4371, S.N. 21071346 FOUND LOOSE RIVETS ON IMPULSE COUPLING DURING INSPECTION, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000710](https://openairdocs.org/sdr/2022FA0000710.md): Impulse Coupling · loose · Nov 18, 2022 · N487A · Magneto/Distributor
  > SLICK MAG P/N 4371, S.N. 20120811 FOUND LOOSE RIVETS ON IMPULSE COUPLING DURING INSPECTION, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000720](https://openairdocs.org/sdr/2022FA0000720.md): Impulse Coupling · loose · Nov 17, 2022 · N514A · Magneto/Distributor
  > SLICK MAG P/N 4371, S.N. 18110538 FOUND LOOSE RIVETS ON IMPULSE COUPLING DURING INSPECTION, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000719](https://openairdocs.org/sdr/2022FA0000719.md): Impulse Coupling · loose · Nov 7, 2022 · N731AC · Magneto/Distributor
  > SLICK MAG P/N 4371, S.N. 21030576 FOUND LOOSE RIVETS ON IMPULSE COUPLING DURING INSPECTION, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000618](https://openairdocs.org/sdr/2022FA0000618.md): Muffler · cracked · Oct 21, 2022 · N7374E · Cessna 172N · Engine Exhaust System
  > NEWLY "OVERHAULED" MUFFLER CRACKED AFTER ONLY 81.3 HOURS OF OPERATION. VISIBLE INDICATION OF FAILURE WAS EXHAUST SOOT ON THE EXTERIOR OF THE MUFFLER SHROUD. MUFFLER WAS SOLD AS OVERHAULED WITH FORM 8130-3 AND WORK ORDER WHILE ALL PARTS APPEARED TO BE MANUFACTU
- [SDR 2022FA0000722](https://openairdocs.org/sdr/2022FA0000722.md): Impulse Coupling · loose · Oct 19, 2022 · N384G · Magneto/Distributor
  > SLICK MAG P/N 4371, S.N. 20060297 FOUND LOOSE RIVETS ON IMPULSE COUPLING DURING INSPECTION, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000721](https://openairdocs.org/sdr/2022FA0000721.md): Impulse Coupling · loose · Oct 12, 2022 · N935G · Magneto/Distributor
  > SLICK MAG P/N 4371, S.N. 21091251 FOUND LOOSE RIVETS ON IMPULSE COUPLING DURING INSPECTION, REPLACED IMPULSE COUPLING WITH NEW.
- [SDR 2022FA0000736](https://openairdocs.org/sdr/2022FA0000736.md): Bushing · unsecure · Oct 1, 2022 · N9825W · Engine (Reciprocating)
  > ENGINE STOP UNCOMMANDED WHILE TAXIING BACK TO MY HANGAR AT MY HOME AIRPORT. DISCOVERED AFTER REMOVING ACCESSORY CASE THAT THE IDLER GEAR BRONZE BUSHING FELL OUT AND CRANKSHAFT GEAR PIN/DOWEL WAS SHEARED OFF AND CRANKSHAFT GEAR AND BOLT WERE LOOSE AND THE TAB O
- [SDR 2022FA0000183](https://openairdocs.org/sdr/2022FA0000183.md): Carburetor · loose · Apr 1, 2022 · N2231Y · Piper PA28181 · Fuel Control/Reciprocating Engines
  > WHERE THE 2 HALVES MEET AND MATE. THE SCREWS HOLDING THEM TOGETHER WERE STILL LOCKED INTO POSITION BY SPECIAL DEVICES. BUT THE HALVES HAD SOME SLIGHT MOVEMENT THAT ALLOWED A SMALL AMOUNT OF FUEL TO LEAK OUT OF THIS POINT. I DID NOT DISASSEMBLE THIS UNIT, BUT I
- [SDR FQAR20210603003](https://openairdocs.org/sdr/FQAR20210603003.md): Capacitor · broken · Jun 3, 2021 · N823PA · Piper PA28181 · Magneto/Distributor
  > DURING RUN UP FOUND RT MAG DEAD, REMOVED MAG AND OPENED UP, FOUND TERMINAL ON CAPACITOR LEAD BROKEN, MAG HAD 138HRS SINCE A 500HR INSPECTION.
- [SDR 2020FA0000530](https://openairdocs.org/sdr/2020FA0000530.md): Control Cable · binding · Dec 10, 2020 · N5907E · Cessna 172 · Mixture Control
  > APPROXIMATELY 20 HOURS AFTER ANNUAL, THE VERNIER MIXTURE CONTROL BECAME VERY STIFF. THERE WERE NO KNOWN ANOMALIES OR WEAR NOTED AT THE ANNUAL. DUE TO THE AGE OF THE PART, IT WAS REPLACED. UPON, DISASSEMBLY THE VERNIER PART OF THE CONTROL APPEARED TO STILL W
- [SDR 2020FA0000506](https://openairdocs.org/sdr/2020FA0000506.md): Impulse Coupling · damaged · Nov 18, 2020 · N526G · Piper PA28181 · Magneto/Distributor
  > RIVETS LOOSE ON IMPULSE COUPLING PAWLS ON SERIAL RANGE OUTSIDE OF S.B.2-19A.
- [SDR 2020FA0000450](https://openairdocs.org/sdr/2020FA0000450.md): Magneto · inoperative · Oct 15, 2020 · N931G · Piper PA28181 · Magneto/Distributor
  > FOUND LOOSE RIVETS ON MAGNETO S/N 18060695 IMPULSE COUPLING. SLICK SB2-19 WAS PREVIOUSLY COMPLIED WITH ON 10/30/2019 AND NEW UNAFFECTED IMPULSE COUPLING HAD BEEN INSTALLED AT THAT TIME. THE PROBLEM FOUND IS THAT NEW IMPULSE COUPLING UNAFFECTED BY SB2-19 STIL
- [SDR FQAR20200916008](https://openairdocs.org/sdr/FQAR20200916008.md): Muffler · deformed · Sep 13, 2020 · N545MA · Piper PA28181 · Engine Noise Suppressor
  > DURING AN INSPECTION BOTH MUFFLERS WERE FOUND WITH HEAT DEFORMATIONS UNDER THE CABIN HEAT SHROUD.
- [SDR FQAR20200916009](https://openairdocs.org/sdr/FQAR20200916009.md): Muffler · deformed · Sep 5, 2020 · N746PA · Piper PA28181 · Engine Noise Suppressor
  > DURING AN INSPECTION BOTH MUFFLERS WERE FOUND WITH HEAT DEFORMATIONS UNDER THE CABIN HEAT SHROUD.

Next page: https://openairdocs.org/engine/lycoming-o-360-a4m/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 = 'O360A4M'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/engine/lycoming-o-360-a4m/reports

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