# SDR BIGA2012022301

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 20, 2012
- Submitted: February 23, 2012
- Operation: Air carrier
- Aircraft: [N700WJ](https://openairdocs.org/aircraft/N700WJ), registered now
- Make and model: Cessna 425
- Registry model: [Cessna 425](https://openairdocs.org/model/cessna-425) (OpenAirDocs)
- Aircraft serial: 4250036
- Aircraft time: 10,877 hours
- System (JASC): [3243 · Master Cylinder/Brake Valve](https://openairdocs.org/jasc/3243)
- Part: Master Cylinder
- Part number: 57170411
- Condition: Worn
- Location: Brake System
- Part time: 10,877 hours
- Stage of operation: TX
- How discovered: C
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/BIGA2012022301

## Discrepancy

AFTER RETURNING THE PILOT REPORTED A "SPONGY" LEFT BRAKE AND REDUCED BRAKING DURING TAXI.  THE MASTER CYLINDER WAS DISASSEMBLED.  THE FLUID OUT OF THE CYLINDER WAS BLACK AND APPEARED TO HAVE BLACK O-RING MATERIAL CONTAMINATING THE FLUID.  THE MASTER CYLINDER WAS CLEANED, INSPECTED, AND REPACKED WITH NEW O-RINGS.  THE SYSTEM WAS FLUSHED, BLED, AND OPS CHECKED NORMAL.  THE O-RINGS APPEARED VERY WORN.

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