# SDR 98ZZZX3684

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 24, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- System (JASC): [2410 · Alternator-Generator Drive](https://openairdocs.org/jasc/2410)
- Part: Nut
- Part number: 642589
- Condition: Cracked
- Location: Alternator
- Component: Teledynecntl, 649304
- 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/98ZZZX3684

## Discrepancy

NEW REPLACEMENT ALTERNATOR CAME WITH THIS NUT ON DRIVESHAFT.  THE CRACK WAS FOUND WHEN NUT WAS REMOVED TO INSTALL DRIVE COUPLING.  COULD BE VERY BAD AS NUT IS INSIDE ENGINE WHEN ASSEMBLED.  SUBMITTER SUSPECTS HYDROGEN EMBRITTLEMENT.

---
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.