Engines And Accessories

Bendix Magneto

Two different Cirrus SR22 aircraft (powered by Continental IO-550-N27 engines) were discovered by the same shop to have broken magneto gear teeth.

The first instance was discovered as a result of engine

roughness during a pre-takeoff engine run-up: The l/h magneto was not firing properly and, upon inspection, the distributor gear (p/n: 10-357586) was found to be missing approximately ten teeth. The second instance was discovered during a routine 500-hour inspection. There was no pre-inspection indication of a problem with the magneto.

Part Average Time: 1665.7 hours.

During an annual inspection, a crack running from the fuel injection nozzle port toward the spark plug port on the number five cylinder (p/n 655932) was discovered.

Part Total Time: 368.9 hours

A technician removed the number six cylinder. While inspecting associated components, spalling was found on the number five exhaust lifter (p/n 653888) and on the numbers five and six intake lifters, causing damage to the camshaft lobes.

Part Total Time: 1250.0 hours

Valve keys (p/n 60009) were pulled through the spring seat (p/n AEL 10077), according to a repair station. As a consequence, the rocker arm tip was destroyed. A hole wore through the valve cover from the upper spring seat, and the valve keys were stuck on the valve stem. The valve stem was damaged and would not pass through the valve guide.

Part Total Time: (unknown)

During an annual inspection of a Piper PA-46-350P, the left turbocharger mounting bracket (p/n 07A19870) was found broken in two places. The submitter speculates the cause was a combination of heat and vibration.

Part Total Time: 1683.8 hours

A technician working on a Piper PA-31-310 with Lycoming TIO-540-J2B engines reports at least two, and possibly three, engine-driven fuel pump failures. Each pump failed as a result of a sheared drive shaft.

Part Average Time: 77.7 hours