# SDR 2018FA0000455

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 9, 2018
- Submitted: October 30, 2018
- Operation: General aviation
- Aircraft: [N56681](https://openairdocs.org/aircraft/N56681), registered now
- Make and model: Maule MX-7-235
- Registry model: [Maule MX-7-235](https://openairdocs.org/model/maule-mx-7-235) (OpenAirDocs)
- Aircraft serial: 10048C
- Engine: Lyc IO540T4B5
- System (JASC): [7322 · Fuel Control/Reciprocating Engines](https://openairdocs.org/jasc/7322)
- Part: Servo
- Part number: RSA5AD1
- Part serial: 70181704
- Condition: Failed
- Location: Engine
- Stage of operation: NR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2018FA0000455

## Discrepancy

WITH A FACTORY OVERHAULED ENGINE, THE FUEL SERVO FAILED AFTER 32.4 HOURS.  AFTER REPAIRED IT LASTED 12.2 HOURS.  THEN INSTALLED A NEW SERVO AND IT ONLY LASTED 3 HOURS.  ALL THREE FAILURES WERE THE SAME, THE MIXTURE SHAFT CAME OUT SLIGHTLY CAUSING A MISALIGNMENT WITHIN THE SERVO WHILE ATTEMPTING RE-START.  THIS COULD BE A SERVO PROBLEM AND OR A FUEL SYSTEM PROBLEM.  HAVE YET TO CONFIRM WHAT IS CAUSING THIS PROBLEM.  A SERVICEABLE OLDER STYLE SERVO SEEMS TO BE ABLE TO OPERATE FINE ON THIS ENGINE.

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