A rubber clutch is used in the hub of many motors to ease the shock of shifting as well as hitting obstructions. These outboards use a stainless steel drive pin. The slippage torque varies with the horse power. The propeller hub should be replaced on your motor if it slips at less than 84 foot pounds of torque. It should also be replaced if it does NOT slip at 104 foot pounds of torque. If you choose to "lock" the clutch with the three screws as suggested, you should also switch from the steel drive pin to a brass shear pin. . . 😉
