How to Take Out an Inboard Ski Boat Drive Shaft

If your prop shaft is bent, you may need to replace it.

The drive shaft of an inboard ski boat may need replacement once or twice throughout the boat's lifetime. Fortunately, ski boats tend to have plenty of room to work, making the process much simpler than automobiles. You need to remove the rudder before uncoupling the drive shaft so you have room to pull the shaft through the stuffing box and out of the hull. You'd be wise to remove the propeller as well to prevent it from getting damaged.

Things You'll Need

• Wrench set
• Flat head screwdriver
• Coupling wrench
• Heat gun

Instructions

1. Remove the floorboards behind the engine compartment by unscrewing the screws that hold it in place.

2. Remove the rudder by taking its supporting cotter pin out and loosening the pinch bolt that holds the rudder in place. Make sure the rudder is supported from underneath, and gently slide it out.

3. Remove the propeller by removing the cotter pin and loosening the propeller nut. Gently tap the hub and slide the propeller off. Be careful not to drop or damage the propeller, as even the smallest dings are expensive to repair.

4. Loosen the four lock nuts that hold the shaft to the transmission coupler with a wrench, and use a coupling wrench to separate it from the drive shaft. Additionally, remove the coupler's set screws. Use a heat gun to heat up the nuts and bolts if they are difficult to remove.

5. Pull the shaft through the stuffing box and out through the bottom of the hull. Gently place it aside in a secure place where it will not roll around or get damaged.

References

• Skidim: Inboard Ski Boat Tech Tips
• Mastercraft: Questions and Answers
• Yacht Survey: Drive System Alignment