# SDR 2015FA0000555

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 15, 2015
- Submitted: November 6, 2015
- Operation: General aviation
- Aircraft: [N13444](https://openairdocs.org/aircraft/N13444), registered now
- Make and model: Waco UBF
- Registry model: [Waco UBF](https://openairdocs.org/model/waco-ubf) (OpenAirDocs)
- Aircraft serial: 3763
- Engine: Cont W670*
- System (JASC): [8500 · Engine (Reciprocating)](https://openairdocs.org/jasc/8500)
- Part: Lock Nut
- Condition: Broken
- 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/2015FA0000555

## Discrepancy

ON REMOVING THE REAR CASE OF THIS ENGINE, FOUND Y BROKEN .3125 LOCK NUTS.   ALSO FOUND 3 BROKEN NUTS ON THE OIL PUMP WHICH IS ATTACHED TOTHE REAR CASE SOME OF THOSE NUTS WERE BROKEN IN 3 SECTIONS.  THE ENGINE WAS O/H.

---
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.