# SDR NX422026031600011

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 13, 2026
- Submitted: March 16, 2026
- Operation: General aviation
- Filed by: [Embry-Riddle Aeronautical University Inc, repair station NX42404M](https://openairdocs.org/faa-repair-station/NX42404M/embry-riddle-aeronautical-university-inc.md) (OpenAirDocs)
- Aircraft: [N979ER](https://openairdocs.org/aircraft/N979ER), registered now
- Make and model: Cessna 172S
- Registry model: [Cessna 172S](https://openairdocs.org/model/cessna-172s) (OpenAirDocs)
- Engine: Lyc IO360L2A
- Engine time: 2,450 hours
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Crankcase
- Part number: LW184025
- Part serial: L3968951E
- Condition: Gouged
- Location: Engine
- Part time: 2,450 hours
- 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/NX422026031600011

## Discrepancy

UPON DISASSEMBLY FOR ITS FIRST OVERHAUL, DAMAGE WAS FOUND ON THE LEFT HAND CRANKCASE HALF TO THREE THRU STUD BORE LOCATIONS. THE DAMAGE APPEARS TO BE A GOUGE WITH DISPLACED METAL JUST UNDER THE CYLINDER PADS JUST INSIDE THE THRU STUD BORES. SIMILAR DAMAGE ON OTHER ENGINES WAS PREVIOUSLY REPORTED. IN ADDITION, ONE OF THE THRU STUDS HAS DAMAGE UNDER THE THREADED PORTION ON THE SHOULDER OF THE THRU STUD.

---
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.