Abstract: An apparatus and method for the removal of carbon particles (soot), odor, gas and particulate from the exhaust of a diesel engine. The method includes a carbon (soot) collector which collects the carbon (soot) and noxious odor which is connected to the catalytic converter of the engine, then enters a heat exchanger for cooling and condensing a major portion of the exhaust into a liquid condensate. The condensate enters a first reactor which neutralizes any acids present in the condensate and passes through an automatic drain into a holding tank. The non-condensed gases flow into a second reactor connected to a holding tank. Gases are reacted in the second chemical reactor with a substance which absorbs the carbon monoxide and nitrogen oxide. The two reactors remove a large quantity of nitrogen oxides and particulate matter. The treated gases then flow into a the soot bath for removal of minute carbon (soot) particles and thence into a vapor remover.

Abstract: The invention relates to a marine wet exhaust system and a method for treating the exhaust from a marine engine. The system comprises a first conduit for receiving an exhaust flow including gaseous, liquid and particulate solid components, a separator for separating the liquid and particulate components from gaseous component, and a second conduit for expelling the gaseous component. A third conduit is provided for receiving from the separator the liquid and particulate solid components, which then pass to a filter for separating the particulate solid component from the liquid component, and the liquid component is discharged via a fourth conduit.

Abstract: Embodiments of personal watercraft that incorporate improved exhaust silencing systems. The silencing systems include an exhaust silencer that silences higher frequency sounds that are difficult to silence with expansion chambers. The silencer is positioned between the water trap and the atmospheric discharge and is disposed substantially vertically so as to facilitate drainage of any water therefrom and to provide further assurances that water cannot enter the engine through the exhaust system.

Abstract: A method and apparatus for treating exhaust gas produced from the combustion of fuels is disclosed. Pollutants such as unburnt hydrocarbons, carbon monoxides, oxides of nitrogen and oxides of sulfur are oxidized by ozone in an ozone contractor, and then resolved by water vapor in a muffler, so that they can be reduced.

Abstract: A water jacketed exhaust pipe comprising an inner liner, an outer shell, and a spray ring. The inner liner includes an internally tapered section which clips the turbulence that occurs along the inner walls of the liner. As a result, fluid expelled from the spray ring will not migrate into the inner liner where it can cause severe corrosion. The outer liner includes an internally tapered section which scatters the stream of water expelled from the spray ring and further redirects water onto the inner liner and into the center of the exhaust path. The redirected water particles are easily vaporized and in the process, extract a significant amount of heat from the exhaust system.

Abstract: An apparatus is disclosed for cleansing and filtering exhaust gas of a vehicle having an internal combustion engine including an exhaust gas cleansing chamber having an exhaust gas inlet and an exhaust gas outlet, the exhaust gas inlet connected to the exhaust pipe of an internal combustion engine, a vaporizer connected to the exhaust pipe so as to introduce water vapor into the exhaust gas before the exhaust gas enters the exhaust gas cleansing chamber, and a sprinkler connected to the exhaust gas cleansing chamber so as to provide a spray curtain of water between the exhaust gas inlet and the exhaust gas outlet to filter impurities from and reduce the temperature of the exhaust gas.

Abstract: A corrosion-resistant, thermally insulative riser elbow for a marine engine. The riser elbow has an exhaust gas conduit made of fiber reinforced ceramic matrix composite (FRCMC) material formed from a polymer-derived ceramic resin in its ceramic state and fibers. Employing a FRCMC material results in a low-cost, light-weight, corrosion-resistant exhaust gas conduit not available with existing riser elbows. In addition, a FRCMC exhaust gas conduit is thermally insulative and so more of the heat of the exhaust is retained rather than being transferred to the conduit. This allows the cooling requirements for the riser elbow to be lowered, while still maintaining a touch temperature below prescribed levels. FRCMC can also be formed into practically any shape and size desired and can be very ductile thereby making the exhaust gas conduit fracture resistant and capable of withstanding thermally-induced strains typical of the environment of a marine engine's exhaust system.

Abstract: An improved exhaust pressure pulsation control apparatus for a marine propulsion system has a front ring, a reflector disk located downstream of the front ring, and a plurality of connecting members connecting the front ring to the reflector disk. Each connecting member has a concave outer edge to facilitate mounting the apparatus within an exhaust tube. A clamp outside of the exhaust tube clamps the exhaust tube against the concave outer edges of the connecting members to secure the apparatus longitudinally within the exhaust tube. The apparatus is preferably made of a fiberglass reinforced thermoplastic material, such as 33% fiberglass reinforced polythalamide or nylon 4,6, through an injection molding process.

Abstract: An apparatus and method for removing gasses and particulate matter from automobile exhaust. The apparatus includes a heat exchanger connected to an automobile exhaust system for cooling exhaust and condensing at least a portion of the exhaust into a liquid condensate. A fluid separator is connected to the heat exchanger and separates the condensate and at least some of the particulate matter from non-condensed gasses. The condensate is passed into a fluid holding tank. The condensate is treated in a first chemical reactor which neutralizes any acids present in the liquid. Non-condensed gasses flow into a second chemical reactor connected to the fluid separator. Gasses are reacted in the second chemical reactor with a substance which absorbs carbon monoxide and carbon dioxide and removes more of the particulate matter. The treated gasses are vented to atmosphere through an exhaust outlet.

Abstract: In an exhaust expansion chamber or tuned pipe of a two-cycle engine in a watercraft, variable amounts of water are injected, thus cooling the temperature within the expansion chamber and matching the sonic wave speed with that of the correct rpm of the motor. Thus, by regulating the temperature of the exhaust gases in the tuned pipe with water, the efficiency of the two-cycle engine at varying revolutions per minute, is improved.

Abstract: A water jacketed exhaust pipe comprising an inner liner, an outer shell, and a spray ring. The inner liner includes an internally tapered section which clips the turbulence that occurs along the inner walls of the liner. As a result, fluid expelled from the spray ring will not migrate into the inner liner where it can cause severe corrosion. The inner liner is longer than the outer shell. The outer liner includes an internally tapered section which scatters the stream of water expelled from the spray ring and further redirects water onto the inner liner and into the center of the exhaust path. The redirected water particles are easily vaporized and in the process, extract a significant amount of heat from the exhaust system.

Abstract: An exhaust pressure pulsation control apparatus for a marine propulsion system has a front ring and a reflector disk located downstream of the front ring. There is a space between the front ring and the reflector disk that is sufficiently large so that the mixture of water and water cooled exhaust passing through the apparatus does not have a significant pressure drop. The apparatus attenuates pressure pulsations in the exhaust system, thereby significantly reducing water ingestion through the exhaust system into the engine. The apparatus does not create significant exhaust back pressure, and typically increases engine maximum power output.

Abstract: An exhaust pipe construction for a motor vehicle includes a connecting device, a discharge device, and a filter disposed between the connecting device and the discharge device. The connecting device is a tee tube having a first port connected to an exhaust port of the engine compartment the motor vehicle, a second port connected to an intake port of the filter tank and a third port opened to the outside environment. The filter tank has a space for accommodating at least one filter unit. The filter tank has the intake port at a front end thereof and a discharge port at a rear end thereof, the discharge port being connected to the discharge device. The space inside the filter tank accommodates treated alkaline water of a predetermined amount. The filter unit has two guide tubes and three fork tubes, all of which have inlets at a baffling frame behind the intake port.

Abstract: A number of embodiments of personal watercraft having catalytic exhaust systems for treating and purifying the exhaust gases. In all of the embodiments, the catalyst is positioned and disposed so as to be protected from water. In addition, arrangements are provided for cooling the catalyst, for circulating ventilating air across it, for isolating it from other components such as the fuel tank, and for permitting its flushing with fresh water after operating in a salt water environment.

Abstract: A catalytic exhaust system for an outboard motor wherein the catalyst is positioned in the drive shaft housing to remove this source of heat from the power head. However, the catalyst is contained within a sealed compartment in the drive shaft housing lower unit. In order to protect the catalyst from water, a trap section is positioned in the power head and this is water cooled by a source of water which has not passed through the engine for its cooling prior to delivery to the trap section. In addition, the guide plate that separates the power head from the drive shaft housing and through which the exhaust gases pass is also water cooled. An arrangement is incorporated for permitting replacement and servicing of the catalytic converter. Although both above the water and below the water exhaust gas discharges are employed, all gases flowing to the atmosphere must pass through the catalytic converter.

Abstract: An exhaust system for a marine propulsion outboard drive wherein the exhaust gases are normally discharged to the atmosphere at a point below the level of the body of water in which the watercraft is operating. A catalyst bed is provided in the exhaust system and the catalyst bed is protected from damage by precluding the flow of water in the exhaust conduit to the catalyst bed in response to certain conditions. These conditions may be either rapid deceleration of the engine or watercraft, stopping of the engine, or any of a combination of sensed factors. The water is precluded either by purging it through air pressure or from generating heat in the exhaust conduit, by providing a heat source in the exhaust conduit that will cause water to vaporize and increase the pressure or by a valve in the exhaust conduit positioned below the catalytic bed. The preclusion of water is initiated for only a predetermined time or until the sensed condition no longer is existent.

Abstract: A marine engine exhaust system (10) and method for use with a marine engine. The exhaust system (10) includes a muffler body (20) defining an internal cavity (22) for receiving exhaust gases from a marine engine (12), the cavity (22) defining a reservoir portion (28) for holding water. The exhaust system (10) also includes at least one inlet passageway (24) communicating with the cavity (22) for receiving exhaust gases from the engine (12) and communicating them to the cavity (22). At least one water supply passageway (32) is provided which communicates with the cavity (22) and which is placed in fluid communication with a water supply such that water can be communicated to the reservoir portion (28). Further, at least one outlet passageway (40) is provided through which exhaust gases and water are ejected from the cavity (22). The outlet passageway (40) has an inlet port (42) disposed in the reservoir portion (28) of the cavity (22) and has an outlet port (44) exterior to the muffler body (20).

Abstract: Two embodiments of exhaust systems for small watercraft that include cooling jackets circling a portion of the exhaust conduit. At least a portion of the water from the cooling jacket is mixed with the exhaust gases but at a point spaced substantially downstream of the cooling jacket so as to reduce the likelihood of water entering the engine through the exhaust system. In one embodiment, an additional cooling jacket is provided to which the coolant from the first cooling jacket is introduced and then discharged into the exhaust conduit. The second cooling jacket is disposed substantially downstream of the first cooling jacket.

Abstract: Disclosed herein is an outboard motor comprising a cylinder block including a lower horizontal drive shaft housing mounting surface, and a cylinder head mounting surface extending upwardly from the drive shaft housing mounting surface, a drive shaft housing including a peripheral outer surface including an upper end, a cylinder block mounting surface at the upper end, and a portion extending rearwardly from the cylinder block mounting surface and having therein a vertically open bore located forwardly of the outer surface, and a cylinder head comprising a cylinder block mounting surface fixed to the cylinder head mounting surface and including vertically spaced first and second recesses adapted to respectively form portions of first and second combustion chambers and respectively including first and second exhaust ports, a bottom surface extending transversely rearwardly from the cylinder block mounting surface of the cylinder head, a projection extending downwardly from the bottom surface and into the bore,

Abstract: An apparatus for controlling automotive emissions by treating of the exhaust gases with treatment chemicals such as cyanuric acid, alcohol, pulverized limestone and/or tetradecylpyridinium bromide. The apparatus for treatment includes a reservoir affixed to an automobile such as in the trunk adapted to receive the fluid chemicals therein and the reservoir conduit for carrying the treatment chemicals to a fluid pump. The fluid pump device is adapted to transfer the fluid chemicals through a pump conduit to an injector housing device which includes an interior plenum chamber for receiving of the liquid chemicals therein. The injector housing includes an outlet with injector members positioned therein for dispersing of the fluid outwardly from the injector housing.

Abstract: The invention includes a method of reducing hydrocarbon emissions from electronic port fuel injected engines by feeding to the catalytic converter an amount effective to reduce hydrocarbon emissions from the engines of chlorine or a chlorine compound.

Abstract: An exhaust system for a small watercraft that includes a water trap device for precluding water entering the exhaust system if the watercraft becomes inverted from entering the engine through the exhaust system. Coolant from the engine is delivered to a cooling jacket that encircles the entire exhaust system and is introduced into the exhaust gases downstream of the water trap so that in the event of inversion and righting the engine coolant will also not enter the exhaust system. This also provides protection for catalyzers in the exhaust system.

Abstract: Methods and apparatuses for muffling steam exhausted from a power plant, in one aspect, the method including flowing the steam into and through a submerged hollow pipe having a plurality of holes spaced apart along it and one or more water eduction tubes through which, due to the effect of the flowing steam, water is sucked into the hollow pipe.

Abstract: An improved exhaust treatment apparatus includes a particulate filter assembly connected to the exhaust system of a diesel engine for removing the solid particulate soot matter entrained in the engine exhaust. The particulate filter assembly includes a disposable low-temperature filter element that can be readily replaced when it becomes clogged. Heat insulated catalyst assemblies located upstream of the particulate filter assembly reduce the amounts of solid particulate matter and other gaseous pollutants in the engine exhaust. A self-cleaning exhaust gas heat exchanger located between the catalyst assemblies and the particulate filter cools the hot, catalyzed exhaust gases before they reach the low temperature filter element. The self-cleaning heat exchanger also includes an intermittent water injection system for periodically removing soot accumulations from the heat exchanger.

Abstract: A marine engine exhaust system and method utilizes first and second enclosed, generally tubular chambers having generally parallel lengthwise dimensions and internal intermediate exhaust passageways spaced along the lengthwise dimension of the second chamber for circulating the exhaust gases through the first chamber, laterally through the intermediate exhaust passageway into the second chamber, along the lengthwise dimension of the second chamber and thence out of an outlet exhaust passageway which passes through the second chamber wall. An outer portion of the second chamber is integrally formed with an outer portion of the first chamber to enhance structural integrity.

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 number of embodiments of exhaust systems for marine watercraft, particularly, those of the jet propelled type. The exhaust systems all include an exhaust pipe which terminates in a discharge opening formed in a lower surface of the hull for discharging exhaust gases through the body of water in which the watercraft is operating. In addition, the exhaust pipe has an ascending and descending section with an expansion chamber communicating with the upper portion thereof through an opening so as to accumulate water if the watercraft becomes inverted and to direct the accumulated water back to the exhaust outlet opening when righted so as to preclude water from flowing to the exhaust ports of the engine. The expansion chamber also acts as a silencing device and may comprise a portion of a Helmholtz resonator.

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: An exhaust gas and pollutant trap is provided for an exhaust system of a motor vehicle, in which the exhaust system is of the type having an engine exhaust pipe and a muffler. The trap consists of a solid support and connection pipe affixed between the engine exhaust pipe and the muffler of the exhaust system of the motor vehicle. A first mechanism included in the trap is carried by the solid support and condenses water vapor from the exhaust gases coming through the engine exhaust pipe. A second mechanism included in the trap, sprays condensed water into the exhaust gases entering the muffler, whereby exhaust gases and solid pollutants are saturated with water and to fall downward to reduce atmosphere contamination.

Abstract: An improved exhaust gas muffler for diesel engines comprises a housing of generally oval shaped cross-chamber, a partition plate disposed therein dividing the housing into an upper chamber and a lower chamber, a first and second generally cylindrical filters rotatably secured within respective lower and upper chambers of the housing, an external rotation means such as an electric motor enabling the rotation of the first and second filters, and a quantity of alkaline cleaning fluid partially filling the lower chamber of the housing and partially immersing a lower portion of the first filter. Wherein, exhaust gas enters the lower chamber of the housing through an inlet and passes through an asbestos sleeve of the first filter permeated with cleaning fluid, which removes carbon precipitates from the exhaust gas.

Abstract: An exhaust system for use with automobile engines and industrial plants for filtering exhaust emissions. An exhaust system comprises the exhaust pipe from the combustion chambers, the dehydrating filters and the cleaning device for the removal of detrimental matter from exhaust gases to protect the environment against pollution. The cleaning device includes the container with an inlet, an outlet and a vertical partition to separate the container into two chambers which contain the water solution of chemical substances to remove the detrimental matter from the exhaust gases. The cleaning device also includes the dehydrating filters. The exhaust gases passing through the water solution and dehydrating filters are caused to give up and deposit the hydrocarbons, the particulate material and to dissolve the pollutant gases, for example, the carbon dioxide and to form the carbonic acid.

Abstract: A valve having a housing including an inlet, an outlet, an internal passage connecting the inlet and the outlet, a pressure responsive member movably supported by the housing for opening and closing the internal passage, and a spring located between the member and the inlet for biasing the member away from the inlet.

Abstract: A marine engine exhaust system and method utilizes first and second enclosed, generally tubular chambers having generally parallel lengthwise dimensions and internal intermediate exhaust passageways spaced along the lengthwise dimension of the second chamber for circulating the exhaust gases through the first chamber, laterally through the intermediate exhaust passageway into the second chamber, along the lengthwise dimension of the second chamber and thence out of an outlet exhaust passageway which passes through the second chamber wall. An outer portion of the second chamber is integrally formed with an outer portion of the first chamber to enhance structural integrity.

Abstract: The invention relates to an improved muffler for an automobile that filters the exhaust and eliminates noise and odor as well as forces steam back into the engine to improve gas mileage. The muffler uses replaceable cartridges that serve as filters to divide the muffler into chambers that filter and eliminate the noise of the exhaust. Each filter can be removed and cleaned as the need arises.

Abstract: A pollution control apparatus is shown for use on automobiles and trucks. This pollution control apparatus fits on the automotive exhaust pipe. A collector unit is secured between the exhaust pipe and tail pipe. The collector unit has a pair of blowers or bladed rotors which are impinged by a mixture of exhaust gases and water which causes the water droplets and dissolved and entrained materials to separate and drain through outlet drains. Water is injected into a U-shaped trap between exhaust pipe and the collector unit. Water from the bottom of the collector unit is pumped by a pump to a reservoir and entrained material is separated by a filter. Water from the filter drains by gravity through a radiator coil and thence to the reservoir from which it flows through vacuum valve to a U-shaped fitting. The water is injected into the exhaust gas stream to wash out entrained and soluble material. The mixture flows through blowers which cause the entrained and water-dissolved material to separate as described.

Abstract: A marine exhaust assembly (10) includes a manifold portion (14), an elbow portion (24), a water jacket portion (38), and exhaust runner walls (40, 42, 44, 70, 72, 74, 76, 78, 80), providing a smooth continuous transition of exhaust gas flow from intake exhaust passages (16, 18, 20, 22) in the manifold portion (14) to transfer exhaust passages (26, 28, 30, 32) in the elbow portion (24) around a bend (34) to a discharge exhaust passage (36), minimizing turbulent flow of exhaust through the manifold portion (14) and elbow portion (24). Each transfer exhaust passage has its own water supply inlet (96, 98, 100, 102) at the upstream end of the respective intake exhaust passage.

Abstract: An exhaust gas purifier unit has a bridged stream corona generator, an oil feeder for feeding oil to the bridged stream corona generator and an oil supplier for supplying an engine with oil stored in and flowing out of the bridged stream corona generator, so as to remove harmful gases contained in the exhaust gas, reliably over an extended period of time.

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: An engine exhaust system for a small watercraft. The engine is fixed to a hull through a damper, while an expansion chamber is fixed directly to the hull. An exhaust port of the engine and an inlet of expansion chamber are connected by an exhaust pipe, and the inlet of expansion chamber and an outlet of exhaust pipe are connected by a fitting with thermal durability and flexibility. In the case where the expansion chamber is followed by a muffler, at least a latter half of the expansion chamber is inserted into the muffler.

Abstract: An apparatus for removing soot from an exhaust gas stream wherein the exhaust gas stream is contacted with water to provide a substantially water saturated exhaust gas stream, particles and droplets in the water saturated gas stream then are electrically charged to produce a gas stream containing electrically charged particles and droplets, and an electric field is established for electrostatically attracting and de-entraining soot and soot containing water droplets from the gas stream containing electrically charged particles and droplets to provide a substantially soot free exhaust gas stream. The present invention includes a precipitator wherein the insulators are positioned in low dew point relatively clean locations and, in one embodiment, includes the use of the exhaust gas stream to maintain the temperature level of the insulators above dew point.

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: This invention relates to a muffler having a purifying system for separating solid contents and eliminating poisonous gases such as carbon monoxide by means of an electrolysis apparatus which continuously provides oxygen separated from water to react with the carbon monoxide into carbon dioxide.

Abstract: A heat exchanger for lowering the temperature of exhaust gas emitted from an internal combustion engine has a container body adapted to store water which serves a heat exchanging medium therein, an exhaust gas discharging chamber adapted to discharge the exhaust gas from the engine into the water in the form of gas-bubbles, a partition member mounted above the surface of water stored within said container body so as to catch splash of water, water-bubbles and vapor generated by evaporation of water and drop them within the container body; an exhaust gas inlet formed in the peripheral side surface of the container body and connected to exhaust pipe for the engine; an exhaust gas introduction passage for connecting the exhaust gas inlet and the exhaust gas discharging chamber; an exhaust gas exit chamber defined in the uppermost part of the inside of the container body; and an exhaust gas outlet pipe connected to the top of said container body to discharge the exhaust gas within the exhaust gas discharge chambe

Abstract: A two stroke internal combustion engine (5) having a transfer port (9) and an exhaust port (8) in a cylinder (6) which are opened and closed in a timed relationship by the reciprocating movement of a piston (7). The exhaust port (8) communicates with an exhaust passage that is tuned to provide a pressure pattern in the exhaust passage that will create at the exhaust port (8) a predetermined pressure pattern while the exhaust port (8) is open. Coolant is supplied to the exhaust passage when the engine is subject to increasing transient load conditions, at engine speeds below the tuned speed, and at a controlled rate to establish a tuned state in the exhaust passage during the transient condition.

Abstract: A method and apparatus for removing soot from an exhaust gas stream wherein the exhaust gas stream is contacted with water to produce a substantially water saturated exhaust gas stream, particles and droplets in the water saturated gas stream then are electrically charged to produce a gas stream containing electrically charged particles and droplets, and an electric field is established for electrostatically attracting and de-entraining soot and soot containing water droplets from the gas stream containing electrically charged particles and droplets to produce a substantially soot free exhaust gas stream. The present invention includes a precipitator wherein the insulators are positioned in low dew point relatively clean locations and, in one embodiment, includes the use of the exhaust gas stream to maintain the temperature level of the insulators above dew point.

Abstract: An improved exhaust system and bearing arrangement for a small displacement outboard motor that is rotatable through substantially 360 degrees for reverse operation. The drive shaft housing is formed with a reduced diameter cylindrical portion that is journaled within the swivel bracket by a bearing arrangement comprised of plastic elements and O-ring elements. The engine has an exhaust system with an exhaust pipe that at least in part encircles the drive shaft and which extends into the drive shaft housing below at least one the bearings to provide sufficient length for tuning and to avoid undue heating of the bearing.

Abstract: A water jacketed exhaust elbow (10) for a marine propulsion system includes an intake exhaust passage (22) communicating with a discharge exhaust passage (26), a water jacket (27) around the exhaust passages, and a trough member (200) extending longitudinally along a water channel (44) along the exterior of the discharge exhaust passage (26) to guide water therealong to mix with exhaust at the end (42) of the discharge exhaust passage (26). The trough member (200) extends beyond the end tip (42) of the discharge exhaust passage (26) and has a sharp edge (202) providing a clean parting surface for the coolant water and preventing ingestion of water back into the discharge exhaust passage (26).

Abstract: An air pollution prevention device that is designed in the preferred embodiment to operate downstream from an existing muffler. The device comprises an oil filled lower chamber with turbulence causing means such as plastic netting through which the exhaust gasses pass. Two upper chambers having turbulence causing means such as steel wool receive the gasses and oil from the lower chamber. The particulate matter in the gasses is coated with oil and being heavier than the exhaust gas will drop out of the exhaust gas and run into the lower oil chamber where it can be periodically removed along with the oil when clean oil is added to the device.

Abstract: An underwater exhaust system which acts to increase the speed of a boat, to reduce fuel consumption, to improve handling and to reduce the skin friction of the water in high seas. The exhaust system basically comprises an exhaust box built into the hull over the bottom of the boat and a diffuser positioned between the exhaust box and the boat bottom. The engine exhaust is directed through the exhaust box and out the exhaust holes of the diffuser into the water. A pump is used to pump seawater into the exhaust box for cooling of the exhaust. Also, there is a step in the hull. The step is positioned approximately 25% from the transom of the stern. The combination of the step and the directing of the exhaust under the hull enhances the speed of the boat and its handling.

Abstract: An exhaust system for a marine propulsion unit having an exhaust conduit into which the exhaust gases and engine coolant are discharged. The exhaust conduit has a separator portion that is affected to separate the coolant from the exhust gases under high speed running conditions so as to achieve maximum power output through a reduction in back pressure but no substantially no separation is provided at low speeds so that silencing will not be adversely affected.