# SDR 2001F00021

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 20, 2001
- Submitted: June 20, 2001
- Operation: Air carrier
- Aircraft: [N6865Z](https://openairdocs.org/aircraft/N6865Z), registered now
- Make and model: Cessna 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (OpenAirDocs)
- Aircraft serial: 421C1068
- Engine: Cont GTSIO520N
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Nut
- Part number: 652241
- Condition: Cracked
- Location: Engine
- 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/2001F00021

## Discrepancy

DURING ANNUAL INSPECTION FOUND NUT CRACKED.  NOTHING UNUSUAL NOTICED AS FAR AS INSTALLATION WAS CONCERNED.  FOUND THAT NUT CRACKED IN THE CENTER OF THE V ON THE SMALLEST DIAMETER PART OF THE NUT.  INSTALLED NEW NUT AND TORQUED TO SPECS.  OTHER ENGINE CHECKED AND FOUND TO HAVE A DIFFERENT STYLE NUT.

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