# SDR 98ZZZX3311

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 20, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N61SD](https://openairdocs.org/aircraft/N61SD), registered now
- Make and model: Bell 47G-3B-1
- Registry model: [Bell 47G-3B-1](https://openairdocs.org/model/bell-47g-3b-1) (OpenAirDocs)
- Aircraft serial: 3551
- Engine: Lyc VO435A1F
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Gear
- Part number: 67687
- Condition: Fractured
- Location: Crankshaft
- Stage of operation: NR
- Nature of condition: Y
- Precautionary procedure: E
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/98ZZZX3311

## Discrepancy

ENGINE FAILED WITHOUT WARNING.  UPON INVESTIGATION, FOUND TIMING GEAR FRACTURED STOPPING THE MAGS.  SUBMITTER STATED SUPPLIER REPORTED THEY HAVE HAD AT LEAST 5 OF THESE FAILURES IN THE LAST 5 YEARS.  THEY CANNOT COME UP WITH A REASON, THEY SAID POSSIBLY TIMING MAY BE SLIGHTLY OFF, TIMING ON THIS ENGINE WAS ON CENTER AND RAN VERY SMOOTH.  SUBMITTER SUGGESTED REPLACING THIS GEAR AT OVERHAUL WITH NEW.

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