Cutlass bearing wear signs

Cutlass bearings (also called cutless) are the rubber-lined bronze sleeves that support the propeller shaft where it exits the strut. Wear signs: (1) Play in the shaft you can feel by hand when the shaft is spinning slowly, grab the shaft between strut and prop, feel for lateral movement. Any movement means the bearing is worn. (2) Vibration at cruise that wasn't there before, often accompanied by a slight thump at idle in gear. (3) Grooving visible on the shaft where it passes through the bearing, pull the prop and inspect. (4) Water intrusion via the shaft seal if the vibration has been ignored long enough to damage the packing gland or dripless seal. Service life: typically 5-8 years for a well-cared boat, 3-5 years in silty water or where the boat sits in slip most of the season (bearings dry out and crack). Replacement requires shaft removal, plan for haul-out. A common mistake: assuming the vibration is a bent prop and repitching it, when the bearing is the real cause. Check the bearing before touching the prop.