# SDR 99ZZZX1200

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 1, 1999
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N215MP](https://openairdocs.org/aircraft/N215MP), registered now
- Make and model: Cessna 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (OpenAirDocs)
- Aircraft serial: 421C1231
- Engine: Cont GTSIO520N
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Bolt
- Part number: 6419311075
- Condition: Broken
- Location: Nr 5 Cylinder
- 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/99ZZZX1200

## Discrepancy

WHILE TROUBLESHOOTING AN OIL LEAK, THE LOWER THRU-BOLT BETWEEN THE NR 4 AND NR 5 CYLINDER WAS FOUND BROKEN APPROXIMATELY .50 INCH FROM THE END.  AFTER CYLINDER REMOVAL AND COMPLETE CRANKCASE AND TORQUE INSPECTION, NO OTHER DEFECTS WERE FOUND.

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