When does my Cutlass Bearing need changing?
Generally you should change your cutlass bearing before it rattles and causes extensive damage. It's worth checking it everytime the boat is out of the water. In practice they seem to last approximatley 10 to 15 years.
The fluting allows water to pass through the bearing - water cooling itself, it is generally this fluting that becomes worn. The weight of the shaft presses down due to gravity on the lower fluting and eventually wears it away.
There should not be any noticable movement if you try to wobble the shaft. Sometimes when the cutlass bearing has dried out and the rubber has contracted there is a minimal noticable movement.
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