Abstract: A drive mechanism for a boat having the motor located inboard. The mechanism disclosed includes a gearbox located outboard of the transom with an input shaft extending toward the inboard motor and an output shaft extending aft toward a propeller shaft. A univerasl joint coupling is provided to drive the propeller shaft while a gimbal ring is employed to universally mount a propeller shaft housing such that the propeller may be used for steerage as well as forward thrust. The gearbox is disclosed as including a first gear pair capable of being changed to provide different output ratios. A second drive link in the gearbox gives a selection of directions of rotation of the propeller shaft. In a first instance, a gear pair is employed. In a second instance, a chain drive is employed. Access is provided into the gearbox by a plate located between the gearbox and the transom. This plate provides a mounting for the drive links within the gearbox.

Abstract: A drive mechanism for power boats having an inboard motor and a stern drive propeller mounting. The device includes a gimbaled propeller shaft housing located outboard of the transom. A gear pair mounted within the propeller shaft housing provides a lower propeller shaft relative to the hull of the boat without requiring a greater propeller shaft angle relative to the hull and without requiring a lowered inboard motor position.

Abstract: A drive mechanism for a boat having the motor located inboard. The mechanism disclosed includes a gearbox located outboard of the transom with an input shaft extending toward the inboard motor and an output shaft extending aft toward a propeller shaft. A universal joint coupling is provided to drive the propeller shaft while a gimbal ring is employed to universally mount a propeller shaft housing such that the propeller may be used for steerage as well as forward thrust. The gearbox is disclosed as including a first gear pair capable of being changed to provide different output ratios. A second drive link in the gearbox gives a selection of directions of rotation of the propeller shaft. In a first instance, a gear pair is employed. In a second instance, a chain drive is employed. Access is provided into the gearbox by a plate located between the gearbox and the transom. This plate provides a mounting for the drive links within the gearbox.