# SDR 2016FA0000513

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 18, 2016
- Submitted: October 18, 2016
- Operation: General aviation
- Aircraft: [N12LC](https://openairdocs.org/aircraft/N12LC), registered now
- Make and model: Cirrus SR22
- Registry model: [Cirrus SR22](https://openairdocs.org/model/cirrus-design-sr22) (OpenAirDocs)
- Aircraft serial: 3952
- Aircraft time: 877 hours
- Engine: Cont IO550N
- Engine time: 877 hours
- System (JASC): [8520 · Reciprocating Engine Power Section](https://openairdocs.org/jasc/8520)
- Part: Bolt
- Part number: 656990
- Condition: Sheared
- Location: Crankshaft
- Part time: 877 hours
- Component: Crankshaft, Cont
- Component part number: 649899
- 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/2016FA0000513

## Discrepancy

DURING START FOR MAINTENANCE THE PROPELLER JERKED TO A STOP. SUBSEQUENT START ATTEMPTS SHOWED NO MOVEMENT OF PROPELLER WHILE STARTER WAS RUNNING. REMOVAL OF THE STARTER AND STARTER ADAPTER REVEALED ALL SIX BOLTS THAT ATTACH THE LARGE GEAR TO THE CRANKSHAFT HAD SHEARED ALLOWING THE LARGE GEAR TO SPIN FREELY ON THE CRANKSHAFT.

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