A jet pump assembly includes a marine engine, a jet drive and a shield adapted to be secured to a transom of a watercraft. The shield has arms to which the marine engine is secured and legs to which an intake mount is secured. The jet drive is supported by the intake mount. The shield has at least one flange adapted to be secured to a middle toon of a pontoon boat. The shield covers an opening in the middle toon through which the marine engine is passed during assembly. A gasket between the shield and opening prevents water from entering the middle toon.

A jet pump assembly includes a marine engine, a jet drive and a shield adapted to be secured to a transom of a watercraft. The shield has arms to which the marine engine is secured and legs to which an intake mount is secured. The jet drive is supported by the intake mount. The shield has at least one flange adapted to be secured to a middle toon of a pontoon boat. The shield covers an opening in the middle toon through which the marine engine is passed during assembly. A gasket between the shield and opening prevents water from entering the middle toon.

An outboard motor includes a first exhaust passage connected to an exhaust port and extending downward from the exhaust port through a support frame on a lateral side of a cylinder head. A first case accommodates an engine. A second case accommodates a propeller shaft. A third case is between the first case and the second case in a vertical direction. An exhaust pipe is between the first case and the second case in the vertical direction. The exhaust pipe is connected to the first exhaust passage. At least a portion of the exhaust pipe is outside the third case as seen in a side view of the outboard motor. An exterior cover is between the first case and the second case in the vertical direction. The exterior cover covers the exhaust pipe.

An outboard motor includes a first exhaust passage connected to an exhaust port and extending downward from the exhaust port through a support frame on a lateral side of a cylinder head. A first case accommodates an engine. A second case accommodates a propeller shaft. A third case is between the first case and the second case in a vertical direction. An exhaust pipe is between the first case and the second case in the vertical direction. The exhaust pipe is connected to the first exhaust passage. At least a portion of the exhaust pipe is outside the third case as seen in a side view of the outboard motor. An exterior cover is between the first case and the second case in the vertical direction. The exterior cover covers the exhaust pipe.

A torque fluctuation absorber includes a first outer helical spline, an intermediate member, an outer member, a first spring, and a second spring. The first outer helical spline is rotatable integrally with a torque transmission shaft. The intermediate member is able to move in a first axial direction and in a second axial direction. The intermediate member is linked with the torque transmission shaft through a first helical spline coupling including the first outer helical spline. Axial movement of the outer member with respect to the torque transmission shaft is regulated. The outer member is linked with the intermediate member through a second helical spline coupling. The first spring biases the intermediate member in the first axial direction. The second spring biases the intermediate member in the second axial direction.

A torque fluctuation absorber includes a first outer helical spline, an intermediate member, an outer member, a first spring, and a second spring. The first outer helical spline is rotatable integrally with a torque transmission shaft. The intermediate member is able to move in a first axial direction and in a second axial direction. The intermediate member is linked with the torque transmission shaft through a first helical spline coupling including the first outer helical spline. Axial movement of the outer member with respect to the torque transmission shaft is regulated. The outer member is linked with the intermediate member through a second helical spline coupling. The first spring biases the intermediate member in the first axial direction. The second spring biases the intermediate member in the second axial direction.

The invention comprises an improved nut for securing a propeller to a drive shaft of a vehicle engine. The invention further comprises a nut that may be securely fastened to the end of the drive shaft of a trolling motor engine without the use of separate tools, such as wrenches or drivers. The invention even further comprises a nut with an exterior portion and a shaft portion that communicates along an axis of the drive shaft of a marine engine against the propeller assembly, the shaft portion having elastomeric materials to interface with the propeller assembly and at least one channel which together absorb vibration, heat and sound from the propeller assembly.

A human driven water propulsion apparatus includes a propeller and a human powered drive coupled to the propeller for driving the propeller. The propeller and human powered drive are connected to and supported by a chassis. Foot pedals are slidably engaged with the helical drive shafts. The helical drive shafts are connected to the propeller through one-way clutches and a gear train such that the propeller is driven by the helical drive shafts when driven by the pedals. In a watercraft application, the chassis is rotatably mounted for rotation between a first position where the propeller is faced in a forward direction and a second position where the propeller is faced in a rearward direction. In a swimmer application, a seat is attached to the chassis by a seat post and straps secure the seat to a user.

A human driven water propulsion apparatus includes a propeller and a human powered drive coupled to the propeller for driving the propeller. The propeller and human powered drive are connected to and supported by a chassis. Foot pedals are slidably engaged with the helical drive shafts. The helical drive shafts are connected to the propeller through one-way clutches and a gear train such that the propeller is driven by the helical drive shafts when driven by the pedals. In a watercraft application, the chassis is rotatably mounted for rotation between a first position where the propeller is faced in a forward direction and a second position where the propeller is faced in a rearward direction. In a swimmer application, a seat is attached to the chassis by a seat post and straps secure the seat to a user.