Squawk Box

August 2019 Issue




Fuel Injection Systems

The following information is derived from the FAA’s Service Difficulty Reports and Aviation Maintenance Alerts.

Cessna T206H Turbo Stationair
Failed Fuel Servo

After installation of a factory-rebuilt engine, a ground-run was performed. At all settings, the engine ran too rich, and adjustments had no effect. Aircraft was not airworthy. Removed fuel servo from engine, sent out for repair. Reinstalled fuel servo after repair, and engine performed satisfactorily. Returned aircraft to service.

Part total time: 0.0 hours
Cessna 310R
Dirty Injectors

Pilot reported a rough-running engine and made a precautionary landing. Inspection revealed small amounts of dirt in the injectors of the affected cylinders. Injectors were cleaned and lines removed, flushed and reinstalled. Technicians found no contamination in the fuel tanks. Fuel transducers had been installed in the fuel lines as part of an engine monitor installation approximately five hours prior to this occurrence. Personnel are speculating that the contamination in the injectors may have been a result of that installation, but could not determine for sure.

LycomingInjectionPartsDiagram

Part total time: Unknown
Cirrus SR22
Failed Injector

While removing the #2 cylinder injector nozzle (p/n 6576682234) for scheduled cleaning, the part in question was found to shear at the cylinder upon removal attempt. This is the second such failure of this type on this engine in recent months. Due to suspicion of other nozzles failing, all six nozzles were replaced with new ones.

Part total time: Unknown
Piper PA-28RT-201 Arrow IV
Failed Servo Plug

During post-accident inspection, a brass plug on the fuel injector servo (model RSA-5AD1, p/n 2524297-10, s/n 55603) was found popped out of the fuel injector servo with its safety wire still attached. This servo contributed to the accident. The aircraft was a total loss.

Part total time: 2350.0 hours
Piper PA-31-350 Navajo Chieftain
FODed Fuel Injectors

During takeoff, the left engine failed to develop full power. The takeoff was rejected. Upon inspection, small unknown foreign debris was found in cylinders #1, #3 and #5 fuel injector nozzles (p/n 2541946). The fuel control unit screen was inspected with no debris found inside. Fuel lines were inspected with no debris inside. All left engine fuel injectors were replaced and the aircraft returned to service with no further issues.

Part total time: Unknown