# SDR HLF2003F00001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 6, 2003
- Submitted: October 22, 2003
- Operation: Air carrier
- Aircraft: N148MA
- Make and model: Cessna 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (OpenAirDocs)
- Aircraft serial: 421C0078
- Engine: Cont GTSIO520*
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Crankcase
- Condition: Cracked
- Location: Engine
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/HLF2003F00001

## Discrepancy

CRACKED CRANKCASE AT NR 7 STUD, BETWEEN CYLINDERS NR 1 AND NR 3.  CRACK IS ON CRITICAL AREA AND EXCEEDS THE MAX ALLOWED IAW SBM 90-17.  PROBABLE CAUSE: OVERTORQUED NUT OR DEFECTIVE CRANKCASE.  REPORTED TO MFG.

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