A self-propelling watercraft system is provided. The watercraft has a base with a plurality of sidewalls extending from the base to form a cockpit. The base also has a recess, where a pump can detachably connect to the hull within the recess. The pump has an intake valve on a first end and a nozzle on a second end that is opposite the first end. The intake valve can intake water. The nozzle can jettison water received in the pump from the intake valve and agitate water surrounding the nozzle.

A jet propulsion system for a watercraft includes a duct defining an inlet, a venturi unit, an impeller housing disposed between the inlet and the venturi unit, and an impeller disposed within the impeller housing. The impeller is rotatable in a forward direction and a reverse direction. The venturi unit includes a venturi conduit and at least one door connected thereto. The venturi conduit has a peripheral wall defining at least one aperture. The at least one door is movable between a closed position when the impeller rotates in the forward direction, and an open position when the impeller rotates in the reverse direction. In the closed position, the at least one door closes the at least one aperture. In the open position, the at least one door opens the at least one aperture such that water flows into the venturi conduit via the at least one aperture.

A jet propulsion system for a watercraft includes a duct defining an inlet, a venturi unit, an impeller housing disposed between the inlet and the venturi unit, and an impeller disposed within the impeller housing. The impeller is rotatable in a forward direction and a reverse direction. The venturi unit includes a venturi conduit and at least one door connected thereto. The venturi conduit has a peripheral wall defining at least one aperture. The at least one door is movable between a closed position when the impeller rotates in the forward direction, and an open position when the impeller rotates in the reverse direction. In the closed position, the at least one door closes the at least one aperture. In the open position, the at least one door opens the at least one aperture such that water flows into the venturi conduit via the at least one aperture.

A multipurpose maintenance tool for a mechanical assembly. The tool includes a central body and an elongated shank extending in a longitudinal direction from the central body to a lever end. A foreign object removing element has a foreign body engaging surface. The element extends from the central body generally opposite the shank. A fastener engaging formation is formed on the shank, the removing element, and/or the central body. The formation is sized and shaped for engaging a fastener on the assembly to selectively tighten and loosen the fastener. A lateral extension extends from the central body to span an opening in the assembly and engage opposite margins adjacent the opening. As the shank is pivoted about the extension, the removal surface pivots about the lateral extension in a direction corresponding to the angular direction of the shank to dislodge foreign objects from the opening in the assembly.

A self-propelling watercraft system is provided. The watercraft has a base with a plurality of sidewalls extending from the base to form a cockpit. The base also has a recess, where a pump can detachably connect to the hull within the recess. The pump has an intake valve on a first end and a nozzle on a second end that is opposite the first end. The intake valve can intake water. The nozzle can jettison water received in the pump from the intake valve and agitate water surrounding the nozzle.

A self-propelling watercraft system is provided. The watercraft has a base with a plurality of sidewalls extending from the base to form a cockpit. The base also has a recess, where a pump can detachably connect to the hull within the recess. The pump has an intake valve on a first end and a nozzle on a second end that is opposite the first end. The intake valve can intake water. The nozzle can jettison water received in the pump from the intake valve and agitate water surrounding the nozzle.

A marine propulsion system includes a water intake guide block with a flow guide passage, a propulsion device including a housing connected to the water intake guide block and a propeller mounted in the housing, a fixed nozzle connected to the housing of the propulsion device, a swinging nozzle connected to the fixed nozzle and biasable leftward and rightward relative to the fixed nozzle, and a contra type bossing pivotally connected to the fixed nozzle and biasable up and down relative to the fixed nozzle. When rotating the propeller, water is sucked into the flow guide passage and propelled by the propeller to eject backward through the fixed nozzle, and the swinging nozzle is biased leftward/rightward to control leftward/rightward turning of the boat, and the contra type bossing is biased upward/downward to control the pitch angle of the boat and forward/backward movement of the boat.

An underwater propulsion unit including a propeller, a motor, and a housing. The motor is disposed further forward in a propulsion direction than the propeller and drives the propeller into rotation. The housing that accommodates the motor and the propeller includes a first portion and a second portion. In the second portion disposed further rearward in the propulsion direction than the first portion, an introduction inlet and a spout outlet are provided. The introduction inlet (21) introduces water into the housing, and water introduced from the introduction inlet and delivered by the propeller is spouted out of the housing. When viewed in a direction parallel to the propulsion direction, the introduction inlet is disposed further outward than the first portion and introduces water into the housing in a direction parallel to the axis of the propeller.

A waterjet propulsion apparatus comprising a motor, an impeller driven by the motor via a drive shaft, and a power source. A fluid flow-path is formed through the apparatus, the flow-path extending from at least one fluid inlet, through two propulsion passages, each propulsion passage extending from a propulsion inlet to an outlet located at a rear end of the apparatus. The impeller is located within the flow-path, after the at least one fluid inlet, and before the propulsion inlet of the each of the propulsion passages. The motor is located outside of the flow-path, between the two propulsion passages, and behind the impeller. The apparatus is advantageous in that it provides a compact and lightweight construction that can, for example, be used as part of a personal marine propulsion device that can be used by an individual.

A self-propelling watercraft system is provided. The watercraft has a base with a plurality of sidewalls extending from the base to form a cockpit. The base also has a recess, where a pump can detachably connect to the hull within the recess. The pump has an intake valve on a first end and a nozzle on a second end that is opposite the first end. The intake valve can intake water. The nozzle can jettison water received in the pump from the intake valve and agitate water surrounding the nozzle.