Kawasaki Jukogyo Kabushiki Kaisha

Yasuo Okada

Yoshimoto Matsuda

Atsufumi Ozaki

Hideaki Ebisui

Yoshinobu Tanaka

Toshio Araki

Akio Miguchi

Hiroshi Yagii

A personal watercraft comprises an engine which is mounted in a body of the watercraft and is equipped with an open-loop water cooling system; a coolant passage in which water for cooling the engine flows; a water flow generator configured to operate in association with the engine to generate a water flow in the coolant passage; and a valve unit configured to restrict a flow of the water in the coolant passage.

Personal watercraft

In a personal watercraft equipped with a multi-cylinder engine including an exhaust collecting system configured to discharge an exhaust gas from the engine, the exhaust collecting system comprising a plurality of exhaust passages respectively corresponding to a plurality of cylinders provided in the multi-cylinder engine, an exhaust collecting passage which is located downstream of the plurality of exhaust passages in a flow direction of the exhaust gas and is configured to collect the plurality of exhaust passages, a water jacket formed at an outer peripheral region of each of the plurality of exhaust passages, for cooling the exhaust gas flowing in the exhaust passages, and a connecting passage configured to connect at least two of the plurality of exhaust passages.

Personal watercraft with engine having exhaust collecting system

An engine for a personal watercraft uses an open-looped cooling system and comprises a cylinder block having a water jacket within which cooling water flows, and a piston that reciprocates within the cylinder block, and a dimension of the water jacket in a reciprocation direction of the piston is equal to or less than a half of a reciprocation distance of the piston.

Engine and personal watercraft

An oil cooler of an engine for small watercraft. The oil cooler typically includes a mounting portion configured to mount the oil cooler on an outer wall face of an engine of the small watercraft, an oil passage configured to allow oil to flow therethrough and lead to outside of the oil cooler at the mounting portion, and a coolant passage through which coolant for cooling the oil flows, wherein the oil cooler is capable of being disassembled such that an inside of at least the coolant passage is exposed.

Oil cooler and small watercraft

A small watercraft including an engine mounted in a body such that an axial direction of a crankshaft corresponds with a longitudinal direction of the body, an oil tank provided such that a longitudinal direction thereof corresponds with the axial direction of the crankshaft, a first communicating port and a second communicating port formed in the oil tank at least two positions spaced apart from each other in the longitudinal direction, a gas-release chamber having a third communicating port and a fourth communicating port provided at two positions spaced apart from each other, and at least one fifth communicating port located to communicate with an ambient side, the gas-release chamber having a bottom face located higher than a liquid level of oil inside the oil tank, wherein the first communicating port communicates with the third communicating port and the second communicating port communicates with the fourth communicating port.

Small watercraft

A small watercraft comprises an engine for propelling a body of the watercraft, an oil tank configured to reserve oil for lubricating the engine, an oil separator configured to separate the oil from a blow-by gas of the engine, and an oil return passage configured to return the separated oil to the oil tank, wherein a baffle member is provided in the vicinity of an opening portion at which the oil return passage opens in the oil tank so as to inhibit the oil from moving from a predetermined direction toward the opening portion of the oil return passage within the oil tank.

An oil separator comprises an oil chamber having a first space on an upper side and a second space on a lower side which communicate with each other. An air-fuel mixture transport pipe is connected to a peripheral portion of the oil chamber so as to communicate with the second space. An oil discharge pipe is connected to a lower end portion of the oil chamber. A blow-by gas discharge pipe is connected to an upper end portion of the oil chamber. The second space communicates with the first space so as to inhibit the oil from flowing from the second space into the first space. The first space communicates with the blow-by gas discharge pipe so as to inhibit the oil from flowing from the first space into the blow-by gas discharge pipe. The flow direction at one end portion of the air-fuel mixture transport pipe substantially corresponds with the circumferential direction of the oil chamber.

Oil separator for engine, and personal watercraft

Disclosed is a jet-propulsion watercraft having a simple structure for drawing water as cooling water, the inside of which may be cleaned easily. The watercraft typically comprises an engine, a water jet pump driven by the engine, a two-part pump casing, at least one water drawing passage provided so as to communicate with an inside of the water jet pump in a portion where the two parts of the pump casing are connected to each other, and a component cooled by cooling water taken through the water drawing passage.

Jet-propulsion watercraft

A first exhaust chamber and a second exhaust chamber are disposed within a body of a watercraft. The first exhaust chamber communicates with an exhaust port of an engine through a first exhaust pipe. A first space of the first exhaust chamber communicates with the second exhaust chamber through a first inverted-U shaped pipe. The second exhaust chamber communicates with another space of the first exhaust chamber through a second inverted-U shaped pipe. The first and second inverted-U shaped pipes are each positioned in the flow path of the exhaust gas and bent to be substantially inverted-U shaped. The other space of the first exhaust chamber communicates with an outside of the body through a second exhaust pipe. An uppermost portion of the first inverted-U shaped pipe and an uppermost portion of the second inverted-U shaped pipe are located higher than a waterline of the watercraft.

Disclosed is a personal watercraft capable of separating and eliminating water contained in fuel without inspecting whether or not the water is present in a fuel tank. The personal watercraft comprises a water separator in a fuel supply passage from a fuel tank for reserving fuel supplied to an internal combustion engine to an air-fuel mixture generating means for mixing fuel with air to generate air-fuel mixture.

Disclosed is a personal watercraft having a water cooling system of an engine, which allows inside of a cooling water passage of an engine or a water passage connected to the cooling water passage to be sufficiently cleaned and a clogged water-supply hole in an expansion chamber to be easily inspected or cleaned. The personal watercraft comprises a first water passage from a water jet pump to a cooling water passage of an engine . Water is forcibly sent by the water jet pump and led to the cooling water passage through the first water passage . The water flows through the cooling water passage while exchanging heat, and the resulting water is discharged outside the watercraft. The personal watercraft further comprises a second water passage opened in a surface of a body of the watercraft and communicating with the first water passage , and an opening/closing means for opening/closing the second water passage

Disclosed is a jet-propulsion watercraft capable of maintaining cooling capability in an exhaust passage even when one cooling water passage is clogged with substances. The jet-propulsion watercraft comprises: an engine having a cooling water passage; an exhaust passage having a double-walled structure comprised of inner and outer walls between which a cooling water passage is at least partially formed; a water jet pump, the water jet pump pressurizing and accelerating water and ejecting the water from the outlet port, and supplying part of the water to the cooling water passages of the engine and the exhaust passage; a water-supply hole formed in the inner wall of the double-walled structure; a first cooling water passage for supplying the cooling water to the cooling water passage between the outer wall and the inner wall; and a bypass passage formed independently of the first cooling water passage.

A deck structure for a personal watercraft is disclosed, wherein, a body of the personal watercraft comprises a hull and a deck having an opening in the rear upper surface thereof. The opening has a substantially rectangular shape in plan view along a length of the body. A seat is placed over the opening. A side opening is formed in an upright portion of the deck under the seat. A detachable hatch is disposed in the side opening, thereby facilitating the mounting and dismounting of an engine in/from a body and the maintenance of the engine.

Growing community of inventors

Akashi, Japan

Yasuo Okada