0394543 JOHNSON FUEL PUMP ASSY.

Illustration 1 g01738715
Air inlet and exhaust system
(1) Air cleaner
(2) Control group for the CGI system
(3) Variable nozzle turbocharger
(4) Air pressure control valve
(5) Head of the ARD
(6) ARD body
(7) Diesel Particulate Filter (DPF)
(8) Purge line to the ARD
(9) Purge valve
(10) Intake manifold
(11) Cooler for the CGI system
(12) Air-to-air aftercooler The engine has an electronic control system. The system controls the operation of the engine and of the Caterpillar Regeneration System (CRS). The CRS consists of an Aftertreatment Regeneration Device (ARD) and a Diesel Particulate Filter (DPF).The system consists of the following components:
Engine Control Module (ECM)
Wiring
Sensors
ActuatorsInlet air is pulled through the air cleaner (1). The inlet air is then compressed and heated by the compressor wheel of turbocharger to about 150 °C (300 °F). The inlet air is then pushed through air-to-air aftercooler core and the inlet air is moved to the air inlet elbow. The temperature of the inlet air at air inlet elbow is about 43 °C (110 °F). Cooling of the inlet air increases the combustion efficiency. Increased combustion efficiency helps to lower fuel consumption. Also, increased combustion efficiency helps to increase horsepower output.Aftercooler core is a separate cooler core. Aftercooler core is installed in front of the core of the engine radiator. Air that is ambient temperature is moved across the aftercooler core by the engine fan. This cools the turbocharged inlet air.From aftercooler core , the air is forced into the cylinder head in order to fill the inlet ports. Air flow from the inlet port into the cylinder is controlled by the inlet valves.
Illustration 2 g01615217
Air inlet and exhaust system
(13) Aftercooler core
(14) Exhaust outlet from turbocharger
(15) Turbine side of turbocharger
(16) Compressor side of turbocharger
(17) Clean gas induction cooler
(18) Exhaust manifold
(19) Exhaust valve
(20) Inlet valve There are two inlet valves and one exhaust valve for each cylinder. Inlet valves open when the piston moves down on the inlet stroke. When the inlet valves open, cooled compressed air from the inlet port is pulled into the cylinder. The inlet valves close and the piston begins to move up on the compression stroke. The air in the cylinder is compressed. When the piston is near the top of the compression stroke, fuel is injected into the cylinder. The fuel mixes with the air and combustion starts. During the power stroke, the combustion force pushes the piston downward. After the power stroke is complete, the piston moves upward. This upward movement is the exhaust stroke. During the exhaust stroke, the exhaust valve opens, and the exhaust gases are pushed through the exhaust port into the exhaust manifold. After the piston completes the exhaust stroke, the exhaust valve closes and the cycle starts again. The complete cycle consists of four stages:
Inlet stroke
Compression stroke
Power stroke
Exhaust strokeExhaust gases from the exhaust manifold enter the turbine side of turbocharger in order to turn the turbine wheel. The turbine wheel is connected to a shaft which drives the compressor wheel. Exhaust gases from the turbocharger pass through the exhaust outlet pipe, the muffler and the exhaust stack.The CGI system sends hot exhaust gas from the DPF to the CGI cooler. The hot exhaust gas is cooled in the CGI cooler. The now cooled exhaust gas passes through an electronic controlled flapper valve. The electronically controlled flapper valve is hydraulically actuated. The engine is using air from the truck's air filter system when the flapper valve is in the full OFF position. As the flapper valve starts to open the flow of cooled exhaust gas from the CGI cooler mixes with the air flow from the air filter. As the demand for more cooled exhaust gas increases the flapper valve opens wider. This increases the flow of cooled exhaust gas from the CGI cooler. As the demand for more cooled exhaust gas increases, the demand for air flow from the engine's air filter decreases.Turbocharger
Illustration 3 g01615256
Turbocharger
(21) Air inlet
(22) Compressor housing
(23) Compressor wheel
(24) Bearing
(25) Oil inlet port
(26) Bearing
(27) Turbine housing
(28) Turbine wheel
(29) Exhaust outlet
(30) Oil outlet port
(31) Exhaust inlet The turbocharger is installed on the exhaust manifold. All the exhaust gases from the engine go through the turbocharger. The compressor side of the turbocharger is connected to the aftercooler by a pipe.The exhaust gases go into turbine housing (27) through exhaust inlet (31). The exhaust gases then push the blades of turbine wheel (28). The turbine wheel is connected by a shaft to compressor wheel (23).Clean air from the air cleaners is pulled through compressor housing air inlet (21) by the rotation of compressor wheel (23). The action of the compressor wheel blades causes a compression of the inlet air. This compression gives the engine more power by allowing the engine to burn more air and more fuel during combustion.When the load on the engine increases, more fuel is injected into the cylinders. The combustion of this additional fuel produces more exhaust gases. The additional exhaust gases cause the turbine and the compressor wheels of the turbocharger to turn faster. As the compressor wheel turns faster, more air is forced into the cylinders. The increased flow of air gives the engine more power by allowing the engine to burn the additional fuel with greater efficiency.Bearings (24) and (26) for the turbocharger use engine oil under pressure for lubrication. The oil comes in through oil inlet port (25). The oil then goes through passages in the center section in order to lubricate the bearings. Oil from the turbocharger goes out through oil outlet port (30) in the bottom of the center section. The oil then goes back to the engine lubrication system.Valve System Components
Illustration 4 g01734074
(32) Rocker arm
(33) Pushrod
(34) Valve bridge
(35) Valve spring
(36) Valve
(37) Lifter The valve system components control the flow of inlet air into the cylinders during engine operation. The valve system components also control the flow of exhaust gases out of the cylinders during engine operation.The crankshaft gear drives the camshaft gear through an idler gear. The camshaft must be timed to the crankshaft in order to get the correct relation between the piston movement and the