A system includes an engine defining a water jacket fluidly coupled to a heat exchanger. An exhaust manifold defines an exhaust manifold cooling passage. A pump is fluidly coupled to the water jacket, and to each of the heat exchanger and the exhaust manifold cooling passage. An engine cooling circuit includes the water jacket, the heat exchanger, and the pump. An exhaust cooling circuit is selectively fluidly coupled to the engine cooling circuit. The exhaust cooling circuit includes the water jacket, the exhaust manifold cooling passage, and the pump. A control valve includes an inlet fluidly coupled to a first portion of the water jacket. A first outlet is fluidly coupled to a second portion of the water jacket. A second outlet is fluidly coupled to the exhaust cooling circuit. The control valve is structured to selectively control flow of coolant fluid through the second outlet.

The present invention relates to a gas heat pump system. The gas heat pump system, according to one embodiment of the present invention, comprises: an air conditioning module comprising a compressor, an outdoor heat exchanger, an expansion apparatus, an indoor heat exchanger and a refrigerant line; and an engine module comprising an engine for combusting a mixture of fuel and air, thereby providing power for driving the compressor. The engine module comprises: a mixer for mixing and discharging the air and fuel; a supercharging means for receiving the mixture discharged from the mixer, compressing same, and then discharging same; an intercooler for receiving the mixture compressed in the supercharging means, cooling same by a heat exchange method, increasing the density thereof, and then discharging same; an adjustment means for receiving the mixture discharged from the intercooler, adjusting the quantity thereof, and then supplying same to the engine; and an exhaust gas heat exchanger for exchanging heat between a coolant and exhaust gas discharged from the engine, wherein the exhaust gas heat exchanger is directly connected to an exhaust manifold of the engine.

A system includes an engine defining a water jacket fluidly coupled to a heat exchanger. An exhaust manifold defines an exhaust manifold cooling passage. A pump is fluidly coupled to the water jacket, and to each of the heat exchanger and the exhaust manifold cooling passage. An engine cooling circuit includes the water jacket, the heat exchanger, and the pump. An exhaust cooling circuit is selectively fluidly coupled to the engine cooling circuit. The exhaust cooling circuit includes the water jacket, the exhaust manifold cooling passage, and the pump. A control valve includes an inlet fluidly coupled to a first portion of the water jacket. A first outlet is fluidly coupled to a second portion of the water jacket. A second outlet is fluidly coupled to the exhaust cooling circuit. The control valve is structured to selectively control flow of coolant fluid through the second outlet.

A fluid-cooled manifold is configured to cool exhaust from an engine. The fluid-cooled manifold includes a plurality of exhaust runners. Each of the exhaust runners includes a runner body having an inlet end and an outlet end, an exhaust conduit extending through the runner body, and a coolant passage extending through the runner body. The fluid-cooled manifold also includes an exhaust collection manifold including a plurality of inlets. Each inlet of the exhaust collection manifold is coupled to the exhaust outlet opening of a respective one of the exhaust runners. The fluid-cooled manifold also includes a coolant feed pipe and a coolant exit pipe. The coolant feed pipe includes a plurality of outlets coupled to the coolant inlets of the exhaust runners. Likewise, the coolant exit pipe includes a plurality of inlets coupled to the coolant outlets of the exhaust runners.

An exhaust conduit for a marine exhaust system includes an inlet end portion connectable to an exhaust manifold, an outlet end portion that directs exhaust gases toward an exhaust system outlet, a catalytic converter assembly arranged between the inlet and outlet end portions, and inner and outer tubes. The inner tube directs exhaust gases from the exhaust manifold to the catalytic converter assembly, and the outer tube surrounds the inner tube to define a cooling liquid passage between the inner and outer tubes. A flange is secured to the inner and outer tubes at inlet ends thereof, the flange being connectable to an outlet of the exhaust manifold. The inner tube has a uniform diameter between the flange and the catalytic converter assembly, and is welded to the flange independently of the outer tube. First and second welds join the inner and outer tubes to the flange at radially inner and outer faces, respectively, of a flange rim.

A cooling structure for an outboard motor comprises an oil case which has an oil chamber for storing lubricant oil for an engine. Said cooling structure further comprises: a main exhaust gas passage which guides exhaust gas to a lower side; a cooling water outbound path which guides cooling supply water taken from outside the outboard motor to an upper side, and cools the periphery of the main exhaust gas passage in the oil case by means of the cooling supply water; a cooling water inbound path which guides cooling discharge water that has cooled the engine to the lower side and cools the oil chamber by means of said cooling discharge water; and a mixed fluid passage which, on a side below the oil case, cools the exhaust gas by mixing the exhaust gas and the cooling discharge water.

An exhaust device of an engine is provided, which includes an exhaust port formed in a cylinder head and connected to an exhaust aperture of a cylinder, an exhaust manifold disposed on a side surface of the cylinder head and formed with a first exhaust passage, an exhaust path constituting part disposed on a side of the exhaust manifold opposite from the cylinder head, and formed with a second exhaust passage, a catalyst disposed on a downstream side of the exhaust path constituting part, an upstream gasket disposed between the side surface of the cylinder head and an upstream connecting member of the manifold, and a downstream gasket disposed between a downstream connecting member of the manifold and an exhaust-manifold-side connecting member of the exhaust path constituting part. The upstream gasket has a larger thermal resistance in an exhaust gas flow direction than the downstream gasket.

An exhaust system is for a marine propulsion device having an internal combustion engine. A catalyst housing has a housing inlet end that receives an exhaust gas flow from the internal combustion engine into the catalyst housing and an opposite, housing outlet end that discharges the exhaust flow out of the catalyst housing. A catalyst is disposed in the catalyst housing. The catalyst has a catalyst inlet end that receives the exhaust gas flow and an opposite, catalyst outlet end that discharges the exhaust gas flow. A catalyst mantel is on an outer periphery of the catalyst. The catalyst mantel has a mantel inlet end and an opposite, mantel outlet end. A radial flange is on at least one of the mantel outlet end and mantel inlet end. A connector mates with an inner diameter of the catalyst housing. The radially extending flange of the catalyst mantel is axially sandwiched between the connector and a radially inner shoulder of the catalyst housing.

A prechamber assembly includes a cylinder head including a coolant cavity, a prechamber body located within the cylinder head, the prechamber body including a nozzle, and an annular sleeve radially surrounding a portion of the prechamber body. The sleeve includes a plurality of coolant inlet holes. A portion of the prechamber body is radially spaced from the sleeve to form a coolant sleeve annulus extending along a length of the prechamber body above the coolant inlet holes. The coolant cavity and the coolant sleeve annulus are in fluid communication through the plurality of coolant inlet holes.

An outboard motor includes a catalyst housing passage disposed inside the V-shaped line, a cooling water passage including at least a portion disposed at a periphery of a catalyst and that guides cooling water that cools an exhaust passage and a vent hole disposed higher than the catalyst and that connects the interior of the cooling water passage to the exterior of the cooling water passage.