# SDR 98ZZZX2031

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 11, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N557DC](https://openairdocs.org/aircraft/N557DC), registered now
- Make and model: Hughes 269C
- Registry model: [Hughes 269C](https://openairdocs.org/model/hughes-269c) (OpenAirDocs)
- Aircraft serial: S1630
- Engine: Lyc HIO360D1A
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Valve Guide
- Part number: 75838
- Condition: Defective
- Location: Nr 3-4 Exhaust
- Part time: 108 hours
- Stage of operation: IN
- Nature of condition: E
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/98ZZZX2031

## Discrepancy

DURING PRE-TAKEOFF RUNUP, ENGINE STARTED VIBRATING AT MID-RPM RANGE AND WOULD NOT ACCELERATE.  FOUND NR 3 AND NR 4 EXHAUST VALVES STICKING.  REAMED GUIDES TO PROPER DIMENSION.  ENGINE HAS 107.6 HOURS SINCE FACTORY OVERHAUL.  THIS OPERATOR HAS HAD NUMEROUS LOW TIME ENGINES WITH THIS PROBLEM.  AIRCRAFT HAVE DASH 10 FUEL INJECTORS AND RUN ON 15W50 OIL AND ALSO RECEIVE PROPER COOL DOWN.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.