since 1940

Cracked oil cooler -Continental engines

2. Excessive engine vibration. Check with a vibration analyzer. High frequency vibrations, are dampened by the engine mount and are not felt by the pilot. The oil cooler has a lot of overhang weight and if it's natural frequency of vibration coincides with the vibration of the engine will vibrate in resonance. Either the cooler needs to be dampened or the engine vibration needs to be changed or reduced. Continental provides a support arm kit p/n EQ 5968 that fastens to the rocker cover on one end and the end of the oil cooler on the other end to reduce oil cooler vibration. This kit is available for O-470 and IO-520 engines. See "vibration" symptom for discussion about counterweight vibrations.