Multiple EGT Probe Failures
I have 270 hours on my 912iS and have had a total of four EGT probe failures in the last 80 hours. The failure always happens at startup, and the failure mode is always the same. There is a small porcelain sensor element located inside the cage on the end of the sensor, and this element breaks loose causing an immediate failure. When I remove the probe the element is laying loosely in the cage and obviously broken. I suspect that either the exhaust flow is breaking the element or it’s happening from the sharp momentary vibration when the iS engine starts. The aircraft is a Bristell and they make their own exhaust systems, but I have verified that the sensor bungs are located properly as per the Rotax guidelines. I know these EGT probe failures are somewhat common, but this seems excessive. Anyone have any ideas?
