Constraints on arrangement of catalysts are reduced, and early activation and long-term performance maintenance of the catalysts are both achieved. An exhaust pipe includes a first catalyst provided in a first exhaust pipe extending upward on the side of an exhaust manifold, and a second catalyst provided in a second exhaust pipe that extends downward from a bent pipe extending from the first exhaust pipe and that is adjacent to the first exhaust pipe. The second catalyst is disposed at a position offset to a higher location from an up-down middle position of the first exhaust pipe.

A marine cooling system performs a temperature adjustment of an object to be cooled such as an internal combustion engine of a marine vessel. The marine cooling system includes a water supply flow passage to supply cooling water to the object, a water drain flow passage to drain the cooling water from the object to reduce an amount of the cooling water that contacts the object, and a flow passage controller to shut off the water to the drain flow passage.

A cooling device for a power source for a boat propulsion apparatus includes a cooling water passage. The cooling water passage includes a passage provided in the power source, in which an engine or an electric motor is used as the power source of the boat propulsion apparatus that propels a boat. Water from outside the boat is taken into the cooling water passage as cooling water to cool the power source, and the cooling water after cooling the power source is drained from the cooling water passage. From the cooling water flowing through the cooling water passage, foreign substances having a size that clogs the cooling water passage are removed. The cooling water passage is provided with a filter device which can filter residual foreign substances remaining in the cooling water.

A marine cooling system performs a temperature adjustment of an object to be cooled such as an internal combustion engine of a marine vessel. The marine cooling system includes a water supply flow passage to supply cooling water to the object, a water drain flow passage to drain the cooling water from the object to reduce an amount of the cooling water that contacts the object, and a flow passage controller to shut off the water to the drain flow passage.

An engine-generator set with a single-cylinder diesel engine and an electrical generator with a rotor secured to the engine crankshaft. The rotor is cantilevered on an end of the crankshaft. The engine has an electrically activatable fuel injector connected to a continuously pressurized fuel supply, such as in a common rail injection system. The engine exhaust passes through a catalyst bed. In a marine version, the catalyst bed is disposed within an injection elbow.

A marine engine has a powerhead, a crankcase and a crankshaft disposed in the crankcase. A cooling system has a cooling passage that conveys cooling water for cooling the crankcase, a pump that pumps the cooling water from a body of water in which the marine engine is operated through the cooling passage, and a valve that controls discharge of the cooling water from the cooling passage.

A cooling system for a marine inboard internal combustion engine includes at least one engine cooling passage disposed in thermal communication with heat emitting portions of the engine. A pump is in fluid communication with the at least one engine cooling passage. The pump draws cooling water out of the at least one engine cooling passage. At least one outlet drain is downstream of the pump for discharging the cooling water that was pumped out of the at least one cooling passage. A switch activates the pump in response to the following: an operator command to stop the engine and/or a speed of the engine being below a threshold speed.

A cooling system is for cooling a marine engine having an engine block and a cylinder head, and a supercharger configured to provide charge air for combustion in the marine engine. The cooling system has a charge air cooler configured to cool the charge air prior to combustion in the marine engine. The cooling system is configured to circulate cooling water from a body of water in which the marine engine is operating to the marine engine and then back to the body of water. The cooling system is further configured to convey the cooling water in parallel to the marine engine and the charge air cooler. A sprayer is configured to spray the cooling water into exhaust gas discharged from the marine engine. The cooling system is configured to convey the cooling water in series to the charge air cooler and then to the sprayer.

An arrangement of exchangers for marinization of a marine engine, including an engine block with in-line cylinders or cylinders in a V, cooled by a cooling fluid, at least one turbocompressor with a hot chamber connected to an outlet and a cold chamber connected to the cylinders of the engine block, a reverser including a housing and containing oil, wherein the arrangement includes: a radiator hose for supplying cooling water, a turbocompressor exchanger, an engine exchanger, a reverser exchanger, a radiator hose for discharging cooling water toward an outlet of combustion gases, downstream from the hot chamber of the at least one turbocompressor,
with these three exchangers being placed in this order and inserted in the circulation direction of the water between the radiator hose for supplying the cooling water and the radiator hose for discharging this same cooling water.

An arrangement of exchangers for marinization of a marine engine, including an engine block with in-line cylinders or cylinders in a V, cooled by a cooling fluid, at least one turbocompressor with a hot chamber connected to an outlet and a cold chamber connected to the cylinders of the engine block, a reverser including a housing and containing oil, wherein the arrangement includes: a radiator hose for supplying cooling water, a turbocompressor exchanger, an engine exchanger, a reverser exchanger, a radiator hose for discharging cooling water toward an outlet of combustion gases, downstream from the hot chamber of the at least one turbocompressor,
with these three exchangers being placed in this order and inserted in the circulation direction of the water between the radiator hose for supplying the cooling water and the radiator hose for discharging this same cooling water.