# SDR 2020FA0000072

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 13, 2018
- Submitted: January 22, 2020
- Operation: General aviation
- Aircraft: [N63SA](https://openairdocs.org/aircraft/N63SA), registered now
- Make and model: Cessna 172M
- Registry model: [Cessna 172M](https://openairdocs.org/model/cessna-172m) (OpenAirDocs)
- Aircraft serial: 17261610
- Engine: Lyc O320D2G
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Cylinder Head
- Part number: LW12416
- Part serial: 13914S04
- 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/2020FA0000072

## Discrepancy

APPROXIMATE 1.5 INCH RADIAL CRACK IN CYLINDER HEAD ADJACENT TO AND OUTSIDE OF THE INTAKE VALVE.  EXTERNAL EVIDENCE OF EXHAUST GASSES ESCAPING FROM CRACK WAS PRESENT AND COMPRESSION TEST PRODUCED FREE FLOW OF SHOP AIR FROM CYLINDER HEAD BETWEEN THE 9TH AND 10TH HEAD FINS ON THE INTAKE SIDE.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.