# SDR DMV2002F00000

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 21, 2002
- Submitted: February 6, 2002
- Operation: Air carrier
- Aircraft: [N81HR](https://openairdocs.org/aircraft/N81HR), registered now
- Make and model: Cessna 421B
- Registry model: [Cessna 421B](https://openairdocs.org/model/cessna-421b) (OpenAirDocs)
- Aircraft serial: 421B0651
- Engine: Cont GTSIO520H
- System (JASC): [8010 · Engine Cranking](https://openairdocs.org/jasc/8010)
- Part: Bearing
- Part number: 680468T
- Condition: Failed
- Location: Starter Adapt
- Part time: 608 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/DMV2002F00000

## Discrepancy

STARTER ADAPTER HOUSING MAIN BEARING FAILURE,  RESULTS IN EXCESSIVE PLAY TO REAR ENGINE GEAR ASSEMBLY ADVISE UPGRADING TO BETTER STYLE OF BEARING DESIGNED FOR BETTER LOADS.  PROVIDE A 500 HOUR INSPECTION THAT MIGHT REQUIRE REMOVAL AND INSPECTION OF BEARING TO PROVIDE BETTER SAFETY MARGIN.  THIS UNIT HAD ALL UPDATES PRIOR TO FAILURE.  HAVING A SPINNING VISCOUS DAMPENER MAY HAVE HAD SOMETHING TO DO WITH ADDED VIBRATION CAUSING BEARING FAILURE.

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