Abstract: An exhaust gas heat exchange system for an internal combustion engine (10) includes an intake manifold (12) including an inlet (16) for recirculating exhaust gases and an exhaust manifold (28) having at least one inlet (30) for receiving exhaust gas from the engine (10) and an outlet (36), (60), for discharging exhaust gas and spaced from the inlets (30). An exhaust gas heat exchanger (32) includes a first flow path having an inlet (50) connected to the exhaust manifold (32) to receive exhaust gas therefrom, an outlet (52) for discharging cooled exhaust therefrom and a second flow path in heat exchange relation with the first flow path for receipt of a coolant whereby exhaust gas flowing in the first flow path may be cooled.

Abstract: An apparatus and method of attaching an exhaust manifold to an engine's cylinder head utilizing an oversized hole in the manifold, a stud fastener extending through the oversized hole, a spacer element around the stud fastener, and a nut adapted to be tightened to engage the spacer element and the flange wherein a flat gasket is compressed to a desired extent which is not so excessive that it inhibits sliding movement caused by thermal growth of the manifold.

Abstract: An exhaust header system for an internal combustion engine having improved exhaust gas flow characteristics. Primary pipes extend from openings in a flange bolted to the engines exhaust ports. The primary pipes come together at a collector pipe into which the primary pipes extend slightly. The ends of the primary pipes are substantially parallel, uniformly spaced around the collector pipe axis and have end surfaces lying substantially in a single plane. A generally pyramidal transition piece has a base corresponding to, and secured to, the primary pile end surfaces so as to cover the area between the pipe ends. The pyramid apex extends along the collector pipe centerline toward the exit end. The length and cross section of the transition piece is selected to provide a smooth transition from the greater combined internal cross section of the primary pipe ends to the lesser cross section of the collector pipe exit end.

Abstract: An exhaust gas heat exchange system for an internal combustion engine (10) includes an intake manifold (12) including an inlet (16) for recirculating exhaust gases and an exhaust manifold (28) having at least one inlet (30) for receiving exhaust gas from the engine (10) and an outlet (36), (60), for discharging exhaust gas and spaced from the inlets (30). An exhaust gas heat exchanger (32) includes a first flow path having an inlet (50) connected to the exhaust manifold (32) to receive exhaust gas therefrom, an outlet (52) for discharging cooled exhaust therefrom and a second flow path in heat exchange relation with the first flow path for receipt of a coolant whereby exhaust gas flowing in the first flow path may be cooled.

Abstract: An exhaust manifold of an internal combustion gasoline engine includes first, second, third and fourth runners and mixing pipe, one end of each runner being connected to a cylinder head and another end of each runner being connected to the mixing pipe wherein the runners are connected to the mixing pipe in a longitudinal direction such that exhaust gases are introduced into the mixing pipe without colliding into an inner wall of the mixing pipe.

Abstract: An exhaust manifold is constructed of material varying in thickness. Auxiliary cooling, such as from an air flow, to a portion of the exhaust manifold, permits making this portion thinner than a portion shielded from the auxiliary cooling. This lowers the heat capacity of the thinner material, allowing the exhaust manifold to heat rapidly to the activation temperature of a catalyst. Thus, the catalyst is capable of removing harmful elements from the exhaust gases of an internal combustion engine more quickly, thereby reducing pollution to the atmosphere. Furthermore, an exhaust manifold having this structure is lighter and requires less material than conventional exhaust manifolds, thereby making production easier and less costly.

Abstract: Several embodiments of personal watercraft employing exhaust systems that incorporate not only a catalyst, but also an exhaust silencing device for silencing the sounds of the exhaust gases. The components are laid out in such a way that there will be minimum heat transfer from the exhaust gases to the engine compartment, and also so that there will be a cooling air flow across the exhaust system to further provide this result. In one embodiment, the silencing device is mounted transversely at the front of the engine, and in other embodiments it is disposed longitudinally to the rear of the engine. In all embodiments, the components are laid out to maintain good fore and aft and side to side balance.

Abstract: An exhaust manifold cooling assembly for an internal combustion engine having a turbocharger, an exhaust a manifold, heat exchanger, and an outer shell. Exhaust gas from the engine passes through the exhaust manifold, the turbocharger, and the heat exchanger. The cooled exhaust gases pass through a cooling passageway disposed about, generally surrounding and spaced from the exhaust manifold. Heat is further absorbed by the cooling exhaust gasses.

Abstract: A watercraft includes a monitoring and control system to sense the operational state of a catalytic device and a cooling system used with an exhaust system of the watercraft. The monitoring and control system includes a collection port formed downstream of the catalytic device. During diagnostic testing of the engine and the catalytic device, a collection element is inserted into the collection port. A plug, however, normally closes the collection port during normal engine operation. A cover extends over the collection port and a substantial portion of the surrounding exhaust pipe. The cover, or at least a portion thereof, is readily removable so as to provide access to the collection port. The exhaust system also includes a water trap located downstream of the collection port. A foam core support member supports the water trap within a hull of the watercraft, with an insulator positioned between the support member and the water trap.

Abstract: A two-cycle, multi-cylinder engine maintains roughly equal temperatures between cylinders, despite differing exhaust efficiencies between the cylinders. Several ways of reducing the temperature of one of the cylinders in comparison to the other are disclosed. One embodiment involves supplying more coolant to the cooling passages around the hotter running cylinder. Other ways involve reducing the compression ratio or retarding ignition timing in the hotter running cylinder in comparison to the other cylinder.

Abstract: A number of the embodiments of exhaust systems and oil tank arrangements for four-cycle internal combustion engine powered outboard motors. In all of the embodiments, idle exhaust gases are discharged to the atmosphere through a path that extends above the oil tank. A cooling jacket is formed around an exhaust pipe that depends through a cavity in the oil tank and coolant from this cooling jacket is discharged to the exterior surface of the exhaust pipe so as to cool it. Cooling water from the engine and from the exhaust pipe cooling jacket is isolated from the idle exhaust gas discharge so as to ensure that this cooling water cannot enter the engine through the idle exhaust gas discharge path.

Abstract: An internal combustion engine of the type utilized to power an outboard motor and having a cooling arrangement for reducing the transmission of heat from exhaust gases flowing through an exhaust passage from the engine to the combustion chambers of the engine, is disclosed. In general, the cooling arrangement comprises an air-filled space formed in the cylinder block between the combustion chambers and the exhaust passage. In a first arrangement, when the engine is of the in-line variety and the combustion chambers are vertically arranged, air spaces are formed between a common vertically extending exhaust passage leading to an exhaust pipe, and each combustion chamber. In a second arrangement, when the engine is of the "V" type, an air space is formed in the portion of the cylinder block defining the inside wall of each cylinder bank, between each combustion chamber and a common exhaust passage extending through the valley between the cylinder banks.

Abstract: An improved exhaust probe arrangement within an exhaust system of a small watercraft increases the accuracy of the probe's readings. The aperture is located upstream of a point where cooling water is introduced into the exhaust system for silencing purposes. As a result, the ingress and egress of exhaust gases flow into and out of the aperture is generally unimpeded by the cooling water. The tendency of water to enter and clog the aperture is also reduced. The precision of the exhaust probe measurements consequently is greatly increased.

Abstract: Disclosed herein is an internal combustion engine including a reactor including opposed first and second ends, an outer shell extending between the opposed ends, and a flow path extending between the opposed ends and including an entry opening at the first end, and a discharge opening at the second end, and an engine member including a plurality of spaced combustion chamber portions each including an exhaust port, an exhaust manifold communicating with the exhaust ports and with the entry opening and including a generally vertically extending open side including a portion closed by the reactor outer shell, and an outer wall spaced from the open side of the manifold and also engaging the outer shell of the reactor.

Abstract: A liquid cooling arrangement for an internal combustion engine having a cylinder block with a cylinder head connected thereto and defining at least one combustion chamber, a common exhaust passage extending through the cylinder block and an exhaust passage leading from each combustion chamber to the common exhaust passage, is disclosed. The liquid cooling arrangement includes a pump for pumping cooling liquid from a cooling liquid source first through at least one passage extending through the cylinder head generally adjacent the exhaust passages leading from the combustion chambers, and through at least one passage extending through the cylinder block generally adjacent the common exhaust passage. Once the cooling liquid has passed through these passages, the cooling liquid is delivered to one or more passages extending through the cylinder head or block generally adjacent the combustion chamber(s).

Abstract: An exhaust gas pipe for multicylinder, supercharged internal combustion engines has an outer gas-tight casing (2) and an inner hot gas pipe (1) made up of segments (5) of cast parts securable by screws (8) which project into the casing (2) from the outside.

Abstract: An exhaust system for a supercharged internal-combustion engine in which of the exhaust-gas-carrying components, the exhaust gas pipes leading from the cylinder outlets to the turbines, or the turbines, or the turbines and the exhaust gas pipes are arranged jointly in an exhaust-gas-tight housing. Openings in the exhaust-gas-carrying components cause the space formed between the exhaust-gas-carrying components and the housing to be filled with exhaust gas. By way of a bypass pipe which is connected with the space and leads to the turbine, exhaust gas can be blown off from the space. A blow-off valve is arranged in the bypass pipe.

Abstract: An internal combustion engine assembly comprising an internal combustion engine including an exhaust port, an exhaust conduit communicating with the exhaust port and having an inner surface, the conduit including first and second conduit portions having respective ends, the first and second conduit portions being connected end-to-end, a catalyst which is located within the conduit and which includes catalytic material and a sleeve surrounding the catalytic material, the sleeve having a length and an outer surface spaced from the inner surface of the conduit along substantially the entire length of the sleeve, the sleeve having thereon a rigid, radially outwardly extending flange captured between the ends of the conduit portions, and a flexible gasket between the flange and the end of one of the conduit portions.

Abstract: In a water-cooled exhaust pipe which is essentially assembled from cylindrical components, the sections of the interior pipe consist of cylindrically bent, rectangular sheet metal blanks which are elastically inserted into an intermediate wall. The construction minimizes the manufacturing costs of the exhaust pipe.

Abstract: The invention relates to new and useful improvements in those types of internal combustion engines which employ a single poppet valve to alternately control both the intake and exhaust flows through the same valve port. The exhaust and intake air interact within a common manifold wherein mixing is prevented by means of pneumatic elements comprising a nozzle and diffuser combination which direct the flow. The invention improves the separation of intake air and exhaust gases within the manifold of engines of this character by curving the flow axis of the diffuser such that its exit plane is more or less aligned with the logitudinal flow axis of the exhaust pipe. A means of throttling the engine by proportionally distributing the intake air within the said manifold between the airchest and exhaust gas circuits in a manner relative to the engine speed is a further improvement.

Abstract: An exhaust gas duct for a row of a plurality of combustion engine cylinders has an exhaust pipe section extending alongside the cylinders and a cooling housing in which the exhaust pipe section is mounted. The cooling housing has a middle longitudinal section and two end sections, one of which is a cover and the other is a mounting connector duct end ring. The middle section has substantially circular end portions with cooling liquid flow ducts therein and a flange portion for mounting to a cylinder head. The middle section is made of extruded standardized stock of light metal which facilitates the manufacture and assembly of the duct. A compact structural volume is also achieved thereby. The extruded stock material assures a good dimensional accuracy, a high surface quality, and good sealing characteristics.

Abstract: An exhaust gas duct for a row of cylinders of an internal combustion engine is so constructed that corrosion, especially fretting corrosion, is minimized by mounting the exhaust gas pipe section in a cooling housing so that contact between the pipe section and the cooling housing is limited to the end portions of the exhaust gas pipe section, thereby leaving an uninterrupted gap between the pipe section and the housing all along the pipe section. The end mountings permit an axial movement, and, if desired, also a radial movement of the pipe section relative to the liquid cooled housing for compensating thermal expansions and contractions. The end mountings are easily accessible for inspection and additionally, permit an easy assembly and disassembly of the components.

Abstract: A small watercraft embodying an improved exhaust system that is substantially completely watercooled by a cooling jacket. The exhaust system includes an elastic joint that is also completely surrounded by the cooling jacket so as to insure adequate cooling under all running conditions. A damming arrangement is incorporated so as to insure that all of the exhaust portions being cooled will be completely encircled with cooling water even when low amounts of water are being circulated and a drain system is also provided so as to insure that the cooling jackets will be drained when the watercraft is removed from a body of water.

Abstract: The present invention provides an improved exhaust emission control arrangement for an outboard motor. A catalyst material holding structure is mounted within an exhaust passage of an engine. A thermally insulating interstice is located between an inner wall of the exhaust passage and the outer periphery of the catalyst material holding structure, so that the interstice physically separates the catalyst material holding structure from the inner wall of the exhaust passage. The interstice prevents significant heat transfer between the catalyst material reaction sites at which exhaust gas cleansing takes place and engine components which are positioned proximate thereto. The invention permits the effective cleansing of exhaust gases under all engine operating conditions.

Abstract: An exhaust gas cleaning system is provided for use with a watercraft engine. A plurality of horizontally positioned exhaust ports are located within an engine cylinder head. An exhaust manifold communicates with each of the exhaust ports at a first end and forms a gas collecting pipe at its second end. The second end of the gas collecting pipe is positioned above the exhaust ports. A generally horizontally positioned exhaust pipe extends from the second end of the gas collecting pipe and continues in a rearward direction. Means are provided for introducing coolant from the engine into the rearwardly extending portion of the exhaust pipe. A removable catalyst member is located within and across the exhaust pipe between the exhaust manifold and the area where coolant is introduced into the exhaust pipe. The catalyst is provided with a plurality of small holes therein, so that exhaust gases may be effectively cleaned.

Abstract: The invention relates to an exhaust gas line for internal-combustion engines which is essentially free of tension at normal engine operating temperature. The exhaust gas line is enclosed by a water-cooled and gastight housing and is manufactured from a helically wound metal strip. Tensions that are the result of axial thermal expansion due to the temperature of the engine are avoided because the edges of the metal strip, in a cold state of the exhaust gas line, are aligned with respect to each other to produce a helical gap therebetween. The gap is just closed due to axial expansion of the exhaust gas line at normal engine operating temperature. Tensions that result from a radial expansion of the exhaust gas line are avoided because the exhaust gas line is mounted in a cold state while being subjected to a radial prestress. The prestress is just compensated for as a result of radial expansion at the normal engine operating temperature.

Abstract: A water-jacketed exhaust manifold for a multi-cylinder internal combustion engine has a plurality of inlet ports which are connected via a cavity in the manifold to an outlet port formed in a face of the manifold. At least one septum member is disposed in the manifold to subdivide the cavity into at least two chambers with each of which are associated at least two inlet ports. Each septum extends in the outlet port to the manifold outlet face. A water-jacketed header pipe is connectible to the manifold face. A gas flow passage in the header pipe is subdivided by at least one septum over the length of the passage. Each header pipe septum is arranged to substantially align with and register with a corresponding manifold septum upon connection of the header pipe to the manifold.

Abstract: An improved liquid cooled heat management system for a snowmobile vehicle is described. To maintain the under-the-hood air temperature at optimum operating values while providing the necessary cooling for the vehicle's internal combustion engine, an air inlet opening is formed in the hood or other body panel of the snowmobile defining the engine compartment and disposed within this engine compartment is an appropriately sized heat exchanger through which the liquid coolant is made to flow when the engine is running. The air inlet opening in the hood or body panel leads into a duct or shroud designed to enclose the heat exchanger or radiator on the fan suction side and a engine-driven fan also disposed within the duct draws outside air through the heat exchanger at a rate that is directly related to engine speed. Because of the manner in which the duct work is structured, warmer, under-the-hood air is effectively isolated from the stream of cold outside air drawn through the heat exchanger.

Abstract: The invention provides a marine propulsion device comprising a powerhead including an exhaust gas discharge port, a gearcase rotatably supporting a propeller shaft connected to the powerhead and including an exhaust gas discharge, and a lower unit including an upper portion supporting the powerhead and a lower portion connected to the gearcase, with the lower unit comprising an inner exhaust housing having a generally vertical wall, an open top in communication with the powerhead exhaust gas discharge port, a bottom having therein a first exhaust gas outlet and a second exhaust gas outlet at the top portion of the wall, and an outer exhaust housing also having a generally vertical wall in surrounding relation to the inner exhaust gas housing and defining a vertically extending generally annular space between the inner and outer exhaust gas housings, the space communicating with the second exhaust gas outlet.

Abstract: Hot exhaust gases from individual cylinders of a diesel engine are cooled and partially cleansed in respective selected heat exchangers. The cooled and partially cleansed exhaust gases discharged from the plurality of heat exchangers are combined and then passed to a single electrostaic precipitation device for further cleansing. When it becomes necessary to regenerate one or more of the heat exchangers, only a single heat exchanger is transferred to a regeneration mode of operation. At this time, all of the other heat exchangers continue to operate in the partial cleansing mode. During the regeneration of the one heat exchanger, the exhaust gases therefrom continue to be mixed with the exhaust gases of the remainder of the heat exchangers. All of the exhaust gases from a given cylinder of the engine always pass through only a single of the heat exchangers.

Abstract: An outboard motor having an improved cooling system wherein liquid coolant is circulated through an exhaust manifold cooling jacket then through a cylinder head cooling jacket and then through an upper portion of the cylnder block cooling jacket. A thermostatic valve controls the flow from the upper cylinder block cooling jacket through a lower cylinder block cooling jacket so as to avoid quenching of the intake charge by coolant which has not reached operating temperature.

Abstract: A liquid cooling system for a four-cycle internal combustion engine utilized as a power plant for an outboard motor. The cooling system is designed so that coolant is first delivered to cool an exhaust manifold in the cylinder block, then the exhaust ports of the cylinder head and the other cylinder head components and then the cylinder block cooling jacket surrounding the cylinder bores.

Abstract: Disclosed herein is a stern drive unit comprising an engine including a coolant jacket and an exhaust port, an exhaust gas discharge system including an exhaust gas manifold communicating with the exhaust port, a high-rise elbow communicating with the exhaust gas manifold, and an exhaust pipe communicating with the high-rise elbow and adapted to convey exhaust gas to an overboard discharge, a high-rise elbow and exhaust gas manifold coolant jacket surrounding the exhaust gas manifold and at least partially surrounding the high-rise elbow and communicating with the exhaust pipe for discharge of coolant from the high-rise elbow and exhaust gas manifold coolant jacket and through the exhaust pipe to an overboard discharge, which high-rise elbow and exhaust gas manifold coolant jacket includes a coolant discharge surface over which coolant is discharged from the high-rise elbow and exhaust gas manifold coolant jacket for flow to the exhaust pipe, a coolant conduit communicating between the engine coolant jacket a

Abstract: The fastening of the thin-walled exhaust pipe inside the liquid-cooled covering takes place by means of screws which are distributed in a cross-sectional plane of the exhaust pipe at the circumference. For receiving the screws, brackets are arranged in the wall of the exhaust pipe which have an internal thread corresponding to the screws. In the mounted state, in the area of each bracket, a radially smaller dimensioned space exists between the exhaust pipe and the covering, which smaller space is eliminated after the tightening of the screws. Instead, the pipe is deformed in the cross-sectional plane of the screws in the sections between the brackets. The extent of the deformation depends on the magnitude of the thermal expansion of the pipe to be expected at the operating state, no constraining forces therefore occur at the pipe which endanger the operation and which result from an obstructed thermal expansion.

Abstract: A heat-resistant casing for an internal combustion engine comprises an outer wall member made of an aluminum alloy by casting and an inner wall member made of ceramic and embedded in the outer wall member at the time of casting of the outer wall member. A coolant jacket is formed in the outer wall member and is communicated with a source of cooling medium so that cooling medium circulates through the coolant jacket.

Abstract: A cooling system is provided for an air-cooled internal combustion engine, and includes at least a first fan for causing air to flow along a path directly surrounding individual air-cooled cylinders of the engine and a radiator disposed in the air-flow path. A first liquid flows around the exhaust manifold, for cooling the same, and through the radiator which is cooled by the air-flow that has passed around the air-cooled engine cylinders.

Abstract: A number of embodiments of cooling systems for internal combustion engines powering marine watercraft wherein the engine cooling jacket delivers its coolant to an exhaust manifold cooling jacket adjacent the inlet end of the exhaust manifold and wherein coolant is delivered from the exhaust manifold cooling jacket to a further cooling jacket around the inlet portion of an exhaust elbow. In one embodiment, a closed cooling system is provided for the engine cooling jacket, exhaust manifold cooling jacket and the elbow cooling jacket. In another embodiment, the system discharges coolant back to the body of water in which the watercraft is operating through a further cooling jacket of the exhaust elbow that communicates with its discharge end.

Abstract: A small watercraft embodying an improved exhaust system that is substantially completely watercooled by a cooling jacket. The exhaust system includes an elastic joint that is also completely surrounded by the cooling jacket so as to insure adequate cooling under all running conditions. A damming arrangement is incorporated so as to insure that all of the exhaust portions being cooled will be completely encircled with cooling water even when low amounts of water are being circulated and a drain system is also provided so as to insure that the cooling jackets will be drained when the watercraft is removed from a body of water.

Abstract: A combination exhaust manifold and exhaust elbow for an internal combustion engine includes an exhaust cavity for receiving exhaust from the engine, an exhaust passage leading from the exhaust cavity, and an exhaust discharge outlet. A first water jacket is provided around the exhaust cavity and a second water jacket is provided around the exhaust discharge passage. A dam is provided between the first and second water jackets, having a passage therein for allowing fluid communication between the first and second water jackets. A warm water inlet is provided in the first water jacket around the exhaust cavity for receiving cooling water which has been warmed by the engine, and which flow is controlled by a temperature sensitive thermostat. A cold water inlet is provided adjacent the discharge exhaust passage.

Abstract: A number of embodiments of exhaust arrangements for two cycle multiple cylinder internal combustion engine. In each embodiment, the cylinder block has exhaust ports that communicate with the cylinder bores and extend through a side surface of the cylinder block. This side is closed by a cover that forms a manifold for receiving the exhaust gases and lengthening the distance between the port and the junction with the manifold. In line and V-type embodiments are disclosed.

Abstract: A muffler cooling device for a V-type engine which includes an engine cooling fan disposed at an end of a crankshaft. An air guide plate is provided at a part of a duct through which air sucked by the cooling fan flows, and the duct has at least one opening through which the air flows as being guided by the air guide plate. The arrangement is such that the air having flown through the opening is led, through a space surrounded by a V-bank formed by cylinder heads and an intake manifold, to an area in which a muffler and exhaust pipes extending from the cylinder heads to the muffler are arranged.

Abstract: A marine drive exhaust system (10, 12, 14) is provided with resilient, shaped rubber O-ring seals (20, 74) between facing surfaces (16, 18) of the exhaust manifold (10) and exhaust elbow (12), and the facing surfaces (70, 72) of the exhaust elbow (12) and the exhaust pipe (14). Each of the shaped O-ring seals has an inner peripheral rib (22, 76) extending peripherally around the exhaust passage and generally conforming to the shape thereof and being spaced laterally between the exhaust passage and the peripheral water passages. Each of the shaped O-ring seals has an outer peripheral rib (28, 82) extending peripherally around the water passages and spaced laterally outward of the inner rib by a gap (30, 84) through which the water passages extend.

Abstract: A divider (25, 22) is integrated into the upper end of an outboard motor exhaust tube (17) so that the exhaust discharging from a pair of engine ports (12a) remains separated for a portion of its downward travel through the tube. The divider separates the exhaust tube itself into multiple individual channels. More specifically, a longitudinally extending vertical plate (25) is disposed within the exhaust tube and extends thereacross. The opposed vertical plate edges are anchored to the vertical exhaust tube walls (18, 19). In the present embodiment, a longitudinally extending cooling tube housing (22) effectively forms part of one of the exhaust tube walls (18) and with the housing itself forming part of the divider.

Abstract: A heat exchanging exhaust manifold is provided, including a manifold casing for collecting the exhaust gases of an internal combustion engine having a rack mounted for sliding inside said manifold casing. The rack includes a water flow cooling circuit. Such a manifold is used with all internal combustion engines whose exhaust gases must be cooled, and in particular with the engines used on oil drilling platforms.

Abstract: A manifold and cooling system for V-type marine engines utilizing two novel exhaust manifold/cooling jacket units, each unit having separate cavities and a flow-through heat exchanger whereby engine coolant circulates through the engine block pumped by a water pump first into a forward cavity of one unit in fluidic communication with an exhaust manifold channel wall then traveling adjacent to the heat exchanger into a rearward cavity and into fluidic communication with a second portion of an exhaust manifold channel wall and then out of the unit via piping to a second unit into a rear cavity with similar fluidic communication with a second exhaust manifold channel wall then along a heat exchanger into a forward cavity and further channel wall contact, out of this unit and back into a engine block to complete the coolant circuit. Raw water is pumped (segregated from the coolant) through each heat exchanger and expelled back to the sea.

Abstract: A liquid cooled exhaust manifold with spaced and separated passages associated with each exhaust port of an associated internal combustion engine and with a transversely extending common coolant distributing passage to evenly supply the separated coolant passages.

Abstract: An improved exhaust system for water craft engines is disclosed, which consists in the main an exhaust manifold connected to the cylinder exhaust port of the engine, an exhaust pipe joined at one end to the exhaust manifold and a diffuser connected at one end to the other end of the exhaust pipe and at the other end to the rest of the exhaust system including a muffler and steam separator. The exhaust pipe is divided into two axial parts, the first vertical, largely U-shaped pipe portion for direct connection to the exhaust pipe at downstream thereof and the second horizontal pipe portion for connection at one end thereof to the first pipe portion at downstream thereof and at the opposite end to the diffuser. The second pipe portion is disposed to extend adjacent to the exhaust manifold and made integral therewith in a rigid assembly, with the first pipe portion being releasably secured to the exhasut manifold and second portion through bolts for easy disassembly in servicing.

Abstract: A method is provided for manufacturing a heat shield for an exhaust system component. The exhaust system component preferably is of tubular nonlinear configuration. The heat shield is formed from a larger pipe having an internal diameter greater than the outer diameter of the exhaust system component. Appropriately dimensioned inwardly directed supports are formed in the larger pipe. The larger pipe then is bent into a nonlinear configuration substantially identical to the configuration of the exhaust system component. The outer pipe then is cut longitudinally in half along its entire length to define a unitary nonlinear heat shield which can be mounted to the exhaust system component. A portion of the remaining half of the larger pipe can be reattached to the heat shield to provide an air gap pipe along a portion of the length of the exhaust system component.

Abstract: Heat shield assemblies are normally connected to engines which have exhaust systems in order to reduce the temperature of the outer surface. The skin temperature of the outer surface of the heat shield assembly must be cooled so that persons coming in contact with such a surface is not burned. The subject heat shield assembly includes a heat source, an inner member and an outer member which respectively define first and second cooling flow paths. The first cooling flow path being adapted to convect heat away from the heat source and the inner member as air passes therethrough and the second cooling flow path being adapted to convect heat away from the inner member and the outer member as air passes therethrough. The air passing through the first and second cooling flow paths effectively reduces the temperature of the outer member so that no one would be burned upon contact therewith.

Abstract: An adapter for isolating vibration and thermal shock incident to the use of water cooled manifolds attached to internal combustion engines comprises a substantially annular resilient flange conformed to receive the water cooling jacket of a manifold in one side thereof and adapted for attachment at the other side to the exhaust ports of an internal combustion engine. The water jacket around the manifold is provided with a sealing peripheral bead which opposes the compression of the hose clamp surrounding the annulus of the adapter. The adapter, furthermore, includes an attachment flange enclosing on the interior thereof an annular stiffener plate through which attachment may be made to the engine. The internal combustion engine includes water cooling cavities around the exhaust ports thereof and contacting surfaces of the adapter are thus constantly cooled, allowing for the use of low temperature materials like neoprene or the like.