# SDR 421C120803

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 5, 2003
- Submitted: December 10, 2003
- Operation: Air carrier
- Aircraft: [N321FL](https://openairdocs.org/aircraft/N321FL), registered now
- Make and model: Cessna 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (OpenAirDocs)
- Aircraft serial: 421C0207
- Engine: Cont GTSIO520L
- Engine time: 1,031 hours
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Crankcase
- Part number: GTSIO520L1B
- Part serial: 292488
- 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/421C120803

## Discrepancy

AT ROUTINE 50 HOUR OIL CHANGE, MAINTENANCE PERSONNEL NOTICED OIL RT ENGINE CYLINDER BASE.  VISUAL INSPECTION INDICATED CRACK BETWEEN NR 1 AND NR 3 CYLINDERS IN CRANKCASE WEB STRUCTURE.

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