Yamaha Hatsudoki Kabushiki Kaisha

Kouhei Natsume

Katsumi Ochiai

Shinichi Hoshiya

A vessel propulsion apparatus includes an exhaust passage guiding an exhaust, discharged from combustion chambers into an exhaust collecting passage, to a catalyst housed in a catalyst housing passage, and a cooling water passage guiding cooling water. The cooling water passage includes an upstream water passage, guiding the cooling water taken into the interior of the vessel propulsion apparatus by a water pump, and a first and second parallel water passage connected in series to the upstream water passage and connected in parallel to each other. The cooling water passage supplies the cooling water from the upstream water passage to each of the first and second parallel water passages to cool the catalyst housing passage by the first parallel water passage disposed along the catalyst housing passage and cool the exhaust collecting passage by the second parallel water passage disposed along the exhaust collecting passage.

Vessel propulsion apparatus and vessel

A V-type engine includes two exhaust manifolds connected to two cylinder banks. First and second exhaust ports, respectively provided in the two cylinder banks, are disposed at an inner side of V-shaped lines. Each exhaust manifold includes N branch pipes and a collecting pipe, where N is an integer not less than 2. The N branch pipes are respectively connected to N exhaust ports including at least one of the first exhaust ports and at least one of the second exhaust ports. The collecting pipe is disposed adjacent to N cylinders that are aligned in a direction parallel or substantially parallel to a crank axis direction and extends from one end to the other end of the N cylinders.

Growing community of inventors

Shizuoka, Japan

Kouhei Natsume