# SDR 2016FA0000439

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 19, 2016
- Submitted: September 19, 2016
- Operation: General aviation
- Aircraft: [N709LU](https://openairdocs.org/aircraft/N709LU), registered now
- Make and model: Cessna 172S
- Registry model: [Cessna 172S](https://openairdocs.org/model/cessna-172s) (OpenAirDocs)
- Aircraft serial: 172S11419
- Aircraft time: 391 hours
- Engine: Lyc IO360L2A
- Engine time: 391 hours
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Exhaust Valve
- Condition: Leaking
- Location: Nr 1 Cylinder
- Part time: 391 hours
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2016FA0000439

## Discrepancy

DURING SCHEDULED 50 HOUR OIL CHANGE AND INSPECTION, CYLINDER NR 1 FAILED DIFFERENTIAL CYLINDER LEAK CHECK, 57/80 PSI, LEAKING BY EXHAUST VALVE.

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