# SDR 99ZZZX576

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 16, 1997
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N707DM](https://openairdocs.org/aircraft/N707DM), registered now
- Make and model: Cessna 421B
- Registry model: [Cessna 421B](https://openairdocs.org/model/cessna-421b) (OpenAirDocs)
- Aircraft serial: 421B0145
- Engine: Cont GTSIO520H
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Journal
- Condition: Clogged
- Location: Crankcase
- 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/99ZZZX576

## Discrepancy

TWO OIL JOURNALS IN CRANKCASE CLOGGED CAUSING TWO PISTONS TO FREEZE AND FAIL.  ON LEFT SIDE OF CRANKCASE THE PISTON BROKE THROUGH CAUSING A FIST SIZE HOLE ON THE RIGHT SIDE OF THE PISTON BROKE THROUGH CAUSING A SILVER DOLLAR SIZE HOLE.

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