# SDR 99ZZZX1429

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 11, 1999
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: N4689U
- Make and model: Cessna U206G
- Registry model: [Cessna U206G](https://openairdocs.org/model/cessna-u206g) (OpenAirDocs)
- Aircraft serial: U20605058
- Engine: Cont IO520F
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Valve
- Part number: 654651A2
- Condition: Worn
- Location: Engine
- Stage of operation: IN
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/99ZZZX1429

## Discrepancy

AT ENGINE TT 378.8 HOURS, REMOVED ALL CYLINDERS AND HONED DUE TO 'GLAZING'. AT ENGINE TT 380.0 HRS, PILOT REPORTED ENGINE RUNNING ROUGH. REPLACED NR 6 CYLINDER ASSY DUE TO 'LOW' COMPRESSION 20/80 PSI.  FURTHER INSPECTION OF CYLINDER REVEALED EXCESSIVELY WORN INTAKE VALVE AND SEAT.  CSB9811B C/W AND SUBMITTED 8-7-98 AT ENGINE TT 285.6 HRS.

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