# SDR L48S2016FA0000447

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 18, 2016
- Submitted: September 20, 2016
- Operation: General aviation
- Aircraft: [N705LU](https://openairdocs.org/aircraft/N705LU), registered now
- Make and model: Cessna 172S
- Registry model: [Cessna 172S](https://openairdocs.org/model/cessna-172s) (OpenAirDocs)
- Aircraft serial: 172S11426
- Aircraft time: 1,269 hours
- Engine: Lyc IO360L2A
- Engine time: 1,269 hours
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Cylinder
- Part number: 05K21104
- Condition: Worn
- Location: Engine
- Part time: 1,269 hours
- Component: Engine, Lyc, IO360L2A
- Component part number: IO360L2A
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/L48S2016FA0000447

## Discrepancy

DURING ANNUAL, 100 HR INSPECTION, MAINTENANCE PERFORMED A DIFFERENTIAL PRESSURE LEAK CHECK OF ENGINE, CYLINDER NR 4 FAILED, 0/80 PSI, LEAKING BY EXHAUST VALVE.  VISUAL INSPECTION CONFIRMED STUCK EXHAUST VALVE.

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