# SDR CHIR1425

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 15, 1995
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N237CH](https://openairdocs.org/aircraft/N237CH), registered now
- Make and model: Boeing 234
- Registry model: [Boeing 234](https://openairdocs.org/model/boeing-vertol-234) (OpenAirDocs)
- Aircraft serial: MJ003
- System (JASC): [6320 · Main Rotor Gearbox](https://openairdocs.org/jasc/6320)
- Part: Clutch Shaft
- Part number: 414D62102
- Condition: Bearing Damaged
- Location: Spiral Bevel
- Part time: 1,294 hours
- Component: 234D62006
- 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/CHIR1425

## Discrepancy

ON AND OFF THRUST LOADING OF THE INNER CLUTCH SHAFT CAUSES AXIAL MOVEMENT OF THE SHAFT.  AS THE ALUMINUM SPACERS (PN 414D6215-1 AND PN 114D6261-1) WEAR, THE AXIAL MOVEMENT INCREASES UNTIL THE INNER SHAFT SHOULDER NEXT TO THE PN 114DS661-1 BEARING CONTACTS THE ROLLERS OF THE 114DS661-1 BEARING.  THIS ON AND OFF CONTACT CREATED A SEVERE SCALLOPING OF THAT SHOULDER ON THE INNER SHAFT.  POSSIBLE SOLUTION WOULD BE TO FABRICATE THE ALUMINUM SPACERS OUT OF A MORE WEAR RESISTANT STEEL TO RESTRICT MOVEMENT.  (X)

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