# SDR 97ZZZX1049

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 27, 1997
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N411MZ](https://openairdocs.org/aircraft/N411MZ), registered now
- Make and model: Cessna 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (OpenAirDocs)
- Aircraft serial: 421C1002
- Engine: Cont GTSIO520*
- System (JASC): [8540 · Reciprocating Engine Rear Section](https://openairdocs.org/jasc/8540)
- Part: Starter Drive
- Part number: 653583A
- Condition: Worn
- Location: Rt Engine
- Part time: 700 hours
- Component: 646209TMD
- 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/97ZZZX1049

## Discrepancy

STARTER DRIVE GEAR WEAR UNACCEPTABLE IAW TELEDYNE CONTINENTAL CSB 94-4 EVEN THOUGH THE SERVICE KIT REQUIRED BY TCM CSB 94-4 HAD BEEN PREVIOUSLY INSTALLED AT ENGINE OVERHAUL.  SUBMITTER SUGGESTED CSB 94-4 MAY NOT BE SUFFICIENT.  RECOMMENDED FLEET DATA BE EXAMINATED TO DETERMINE NUMBER AND FREQUENCY OF OCCURRENCES.

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