# SDR 97ZZZX5142

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 12, 1997
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: [N491K](https://openairdocs.org/aircraft/N491K), registered now
- Make and model: Dhav DHC3
- Aircraft serial: 434
- Engine: Pwa R134059
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Cylinder
- Part number: 126743
- Condition: Failed
- Location: Nr 8 Exh Rocker
- Stage of operation: CR
- Nature of condition: E, R
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/97ZZZX5142

## Discrepancy

AKN - EN ROUTE AIRCRAFT EXPERIENCED ENGINE ROUGHNESS.  PILOT LANDED AIRCRAFT AT REINDEER BAY, NAKNEK LAKE.  PROBLEM WAS DETERMINED TO BE EXHAUST SIDE ROCKER CHAMBER CRACKED THROUGH ROCKER AXLE PIN BORES.  SUSPECT CAUSES:  COULD BE INCORRECT ROCKER AXLE TORQUE OR VALVE STICKING.

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