# SDR 2026FA0000796

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 30, 2026
- Submitted: September 30, 2026
- Operation: General aviation
- Aircraft: [N621K](https://openairdocs.org/aircraft/N621K), registered now
- Make and model: Cirrus SR22
- Registry model: [Cirrus SR22](https://openairdocs.org/model/cirrus-design-sr22) (OpenAirDocs)
- Aircraft serial: 5063
- Aircraft time: 594 hours
- Engine: Cont IO550N
- Engine time: 594 hours
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Lock Tab
- Part number: 501868
- Condition: Misinstalled
- Location: Engine
- Part time: 594 hours
- Stage of operation: IN
- How discovered: V
- Nature of condition: W
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2026FA0000796

## Discrepancy

REMOVED THE #2 AND #4 CYLINDER INTAKE AND EXHAUST ROCKER COVERS FOR ROUTINE GASKET REPLACEMENT. UPON INSPECTION OF THE VALVE ASSEMBLY, I FOUND THE LOCKING TAB WASHER P/N: 501868, FOR THE CYLINDER ROCKER ARM SHAFT HOLD DOWN BOLTS TO NOT BE BENT INTO THE LOCKING POSITION. THIS COULD CAUSE THE ROCKER ARM SHAFT HOLD DOWN BOLTS TO BACK OUT LETTING THE ROCKER ARM PULL OUT OF POSITION CAUSING CATASTROPHIC ENGINE FAILURE.

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