# SDR 2000ZZZX232

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 18, 1999
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: N500AB
- Make and model: Cessna 421B
- Registry model: [Cessna 421B](https://openairdocs.org/model/cessna-421b) (OpenAirDocs)
- Aircraft serial: 4210369
- Engine: Cont GTSIO520H
- System (JASC): [7200 · Engine (Turbine/Turboprop)](https://openairdocs.org/jasc/7200)
- Part: Nut
- Part number: 652541
- Condition: Cracked
- Location: Lt 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/2000ZZZX232

## Discrepancy

FOUND LOWER FORWARD ENGINE CASE THROUGH-BOLT NUT (LEFT) CRACKED ENTIRELY THROUGH.  THIS IS THE NEW TWELVE POINT FLANGED NUT REQUIRED BY TELEDYNE CONT M92-9.

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