0324679 EVINRUDE O-RING, Valve core,

Illustration 1 g00637221
Air Inlet And Exhaust System With Turbocharger For A High Pressure Fuel System (1) Gas pressure regulator. (2) Balance line. (3) Carburetor. (4) Air cleaner. (5) Turbocharger. (6) Gas Supply. (7) Governor. (8) Aftercooler. (9) Air inlet manifold. (10) Cylinder. (11) Differential pressure regulator. (12) Exhaust manifold.
Illustration 2 g00637450
Air Inlet And Exhaust System With Turbocharger For A Low Pressure Fuel System (AA) Exhaust gas. (BB) Air and gas to cylinders. (CC) Gas supply. (DD) Low pressure gas. (EE) Air inlet. (1) Gas pressure regulator. (2) Balance line. (3) Carburetor. (4) Air cleaner. (5) Turbocharger. (6) Gas supply. (7) Governor. (8) Aftercooler. (9) Air inlet manifold. (10) Cylinder. (11) Differential pressure regulator. (12) Exhaust manifold.Some air inlet and exhaust systems have an attachment for a gas shutoff valve in the supply line. This valve is electrically operated from the ignition system. The valve can be operated manually in order to stop the engine. When the engine has been stopped, the valve must be manually reset.Engine installations that use dual fuel systems have similar components to the components in the above illustration. Engines that use dual fuel systems use a negative pressure regulator for one of the fuels. These engines have a load valve that can be used to adjust one of the fuels. Adjustments for differences in the BTU content of the gas that is being used can be made with the additional components. Engines that use dual fuel systems can change fuels automatically. Engine timing must be adjusted when the fuel is switched.Changes in engine load and changes in the fuel that is being burned cause changes in the rpm of the turbine wheel. Changes in engine load also cause changes in the turbine wheel of the turbocharger (5) .When the turbocharger gives a pressure boost to the inlet air, the temperature of the air increases. A water cooled aftercooler (8) is installed between the carburetor (3) and the air inlet manifold (9). The aftercooler reduces the air temperature from the turbocharger.Aftercooler
The aftercooler is installed on the top of the inlet manifold. Water flow through the aftercooler lowers the temperature of the inlet air from the turbocharger. With cooler air, an increase in weight of the air will permit more fuel to burn. This gives an increase in power.Gas Pressure Regulator
Illustration 3 g00579946
Regulator Operation (1) Spring chamber. (2) Spring. (3) Locknut. (4) Adjustment screw. (5) Balance line. (6) Outlet. (7) Main diaphragm. (8) Lever side chamber. (9) Lever. (10) Pin. (11) Valve stem. (12) Inlet.The fuel pressure regulator is on the left side of the engine. Adjustment of the regulator is made by turning the adjustment screw (4) .Gas flows through the inlet (12), main orifice, valve disc, and the outlet (6). Outlet pressure is felt in the chamber (1). This outlet pressure comes from the turbocharger boost from the balance line (5). The diaphragm (7) is pushed against the spring. This moves the lever (9) at pin (10). The valve stem (11) moves the valve disc (not shown) in and out. This changes the amount of gas flow.When the inlet orifice is closed, gas is pulled from the lever side of chamber (8). The gas now flows through outlet (6). This reduces the pressure in chamber (8). The pressure in the chamber is now less than the pressure in the chamber on the spring side. Force of spring and air pressure in the chamber on the spring side moves the diaphragm toward the lever. The lever moves downward and the valve disc opens. When the valve disc is open, additional gas is able to flow to the carburetor.The regulator sends gas to the carburetor at a preset amount when the pressure on both sides of the diaphragm is equal.High Pressure Carburetor
Illustration 4 g00579948
Operation of the carburetor (1) Connection for the balance line. (2) Air horn. (3) Outer chamber. (4) Fuel valve. (5) Tube for fuel outlet. (6) Spring. (7) Load valve. (8) Chamber. (9) Inner chamber. (10) Ring. (11) Diaphragm. (12) Fuel inlet. (13) Throttle plate.
Illustration 5 g00579951
Operation of the carburetor (View A-A) (1) Connection for the balance line. (2) Air horn. (7) Load valve. (12) Fuel inlet.Air goes into the carburetor through air horn (2). The air fills the outer chamber (3). Air goes into inner chamber (9). This inner chamber is also known as the mixing chamber. The air goes into this mixing chamber by moving the diaphragm (11) away from ring (10). There are three diaphragms in this carburetor. Fuel flows into the carburetor through fuel inlet (12). The fuel flows past the load valve (7) and flows to the center of the carburetor. Fuel flows into tube (5) which is for the fuel outlet. Fuel valve (4) is fastened to diaphragm (11). When the diaphragm has moved away from the ring (10), fuel flows through the fuel valve (4). The fuel then flows into chamber (9). The mixture of fuel and air that is in the inner chamber (9) flows past the throttle plate (13). The fuel flows into the inlet manifold.When the engine is stopped, spring (6) holds diaphragm (11) against ring (10). Fuel valve (4) is held closed. No air or fuel can go to the inner chamber (9). When the engine is started, a vacuum is created in the cylinders. This vacuum is created from the intake strokes of the pistons. The intake strokes of the pistons create a low pressure condition in the inner chamber (9). This low pressure goes through small holes behind the diaphragm. The low pressure is felt by chamber (8) because of the diaphragm. This permits the pressure in chamber (8) to balance with the low pressure condition in the inner chamber. When the inlet pressure on the diaphragm (11) is higher than the spring force, the diaphragm moves out. Fuel valve (4) moves out. Air and fuel are now able to go into the inner chamber.
Illustration 6 g00637475
Carburetor For A G3412 Engine (14) Load valve. (15) Carburetor.
Illustration 7