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timotb
03-24-2014, 03:19 PM
My RV7 with Lycoming IO-360 M1B and AFS 3500 with engine sensors has not flown yet but shows about an hour AFS tach and 3 on the hobbs ground time. Today I fired the engine up first time since January. Engine sounded normal and nice. I noticed within a few minutes the number 4 CHT was off the scale above 700. I was preparing to shut down but instead gave the throttle a quick pump. The temp began to drop immediately and continued to fall below normal temp to 140s. Other cylinders were 350 plus or minus. All four EGT's were are consistent during this run. Engine sounded, smelled, behaved normal at all times. I suspect a connection issue or sensor failure? Comments?

Tim

Rob Hickman
03-25-2014, 08:28 AM
My RV7 with Lycoming IO-360 M1B and AFS 3500 with engine sensors has not flown yet but shows about an hour AFS tach and 3 on the hobbs ground time. Today I fired the engine up first time since January. Engine sounded normal and nice. I noticed within a few minutes the number 4 CHT was off the scale above 700. I was preparing to shut down but instead gave the throttle a quick pump. The temp began to drop immediately and continued to fall below normal temp to 140s. Other cylinders were 350 plus or minus. All four EGT's were are consistent during this run. Engine sounded, smelled, behaved normal at all times. I suspect a connection issue or sensor failure? Comments?

Tim

It is most likely a bad wire or connection between the EMS connector and probe.