# SDR 98ZZZX4514

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 1, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N7459T](https://openairdocs.org/aircraft/N7459T), registered now
- Make and model: Cessna 172A
- Registry model: [Cessna 172A](https://openairdocs.org/model/cessna-172a) (OpenAirDocs)
- Aircraft serial: 47059
- System (JASC): [7820 · Engine Noise Suppressor](https://openairdocs.org/jasc/7820)
- Part: Seal
- Part number: 05501570
- Condition: Missing
- Location: Muffler
- Part time: 4,774 hours
- Component: Hanlon
- 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/98ZZZX4514

## Discrepancy

EACH MUFFLER REQUIRED 3 SEALS, 0550157-29-30 AND -31 WHICH PROTECTS THE HEATER PINS FROM DAMAGING THE WALL OF THE MUFFLER FROM FRACTURING RESULTING IN OXYGEN ENTERING THE CABIN.  THERE WAS ONLY ONE SEAL TOTAL IN THE 2 UNITS.  REP ADVISED 6 SEALS ARE REQURIED TO ENSURE AIRWORTHINESS.  THE LAST ANNUAL INSPECTION THAT C/W WITH THE MANUFACTURER'S REQUIRED FORMAT WAS JULY, 1985.  SUBSEQUENT INSPECTIONS MADE NO REFERENCE IN MAINTENANCE RECORDS OF C/W MUFFLER INSPECTIONS.

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