Look for one looseness in the linkage from the shift handle to the shifter dog clutch. Loose screws and worn parts can reduce the amount of clutch movement. This will accelerate ware, as the clutch will not fully engage.
Condition of the propeller is also a factor. Damaged blades can induce cavatation. The propeller clutch must not slip below 150 foot pounds of torque. It is also defective If it doesn’t slip at 180 Foot pounds. . . 🙂
