When last did you undertake a critical evaluation of your boat’s propeller? If it’s been a while since you checked the status of your prop, then it is time to do this easy
task when your boat next comes out of the water. It is easy to assess what maintenance needs to be done after a thorough inspection. Here is Leisure Boating’s prop inspection checklist that’ll keep your boat running smoothly on the plane.
THE BLADES
Whether your boat has an inboard motor, sterndrive or outboard motor, this step requires you to carefully check the blades for damage. Larger dings and chunks missing from the blades are easy to spot whereas slightly bent propeller blades might not be as apparent. Bent blades will often create vibrations when under way.
If you look at the propeller from the side it is often easier to detect if one of the blades is out of alignment. Alternatively, measure the distance from the outer edge of the blade to a fixed object or point, such as a spot on the hull to determine the variances between the different blades. If there are discrepancies in this distance, it means that the blades are bent and need to be realigned to the correct pitch and rebalanced by a marine dealer.
THE SHAFTS
A clear indicator that you might have a bent prop shaft is vibration when you are under way. If you’ve ruled out a bent or damaged propeller is causing the vibration, your next step is to check the status of the prop shaft.
Check the bearings on inboard motors. If you suspect that your prop shaft is bent, you will need to get a prop shop to either straighten out the current shaft or replace it with a new one.
The marine dealer attending to the bent prop shaft should also check couplers, seals and bearings that could have been damaged by the continual vibration of the prop.
If you are replacing the prop shaft yourself, make sure it has liberal amounts of marine grease on it before it is replaced as this will make removal much easier the next time.
