Common Rail Engine Power System
The system consists of a fuel supply system, which includes a fuel tank, a fuel filter with a booster pump, fuel injection pump, injectors, fuel lines
The system also includes an air supply system, which consists of an air filter, a turbocharger, a charge air cooler, and an intake pipe.
A fuel intake with a coarse mesh filter is installed in a stamped steel tank.
The fuel tank is mounted on the frame.
From the tank, the fuel is supplied through a pipeline through a fine filter to the high-pressure fuel pump (high pressure fuel pump). From the pump, high-pressure fuel enters the rail, from which it is supplied to the injectors.
The fuel intake is attached to the tank with a clamping ring with screws through a rubber O-ring.
The high pressure pump supplies fuel to the high pressure common fuel line, regardless of engine speed.
Fuel under high pressure is stored in this fuel line, from where it is continuously supplied to the injectors.
In this pump, the fuel pressure is increased to 250 - 1600 bar in three radial pressure chambers.
The electronic fuel supply control valve, installed at the inlet to these chambers, regulates the amount of fuel supplied to them.
To do this, it uses signals from the ECM, which maintains the pressure in the high pressure common rail at the required level.
Fuel that does not enter the pressure chambers exits through the cascade bypass valve.
It directs part of the fuel under pressure into the channels of the high-pressure pump lubrication system and then drains the fuel into the tank.
The fuel rail stores fuel and distributes it between the fuel lines of the individual injectors.
A sensor is installed in the rail, which monitors the pressure created in it by the high-pressure pump.
The signal from this sensor is used by the ECM to regulate the high pressure fuel pump flow. In addition, there is a pressure reducing valve in the common fuel line.
It works as a safety valve, relieving excess pressure if the pressure in the fuel line exceeds a set level.
Fuel drained from the high pressure common fuel line is returned to the fuel tank via the fuel return line.
The injection pump is driven by gears from the rear end of the crankshaft.
A mechanical booster pump is also installed in the pump housing, which ensures the suction of fuel from the tank.
A fine fuel filter with a replaceable filter element assembled with a fuel supply pump is designed to clean the fuel in the engine power system from mechanical impurities and water.
It is located in the engine compartment on the left-hand side of the frame side member.
On the filter housing there is an air outlet closed with a bolt, a mesh filter for pre-cleaning the fuel and a valve for draining sediment (water).
To prevent clogging of the filter in cold weather, an electric fuel heater is built into the filter housing.
The air filter is installed on the right side of the engine compartment.
In the air filter, the air entering through the air intake is filtered by passing through the curtains of the filter element.
Then, through the pipe in the upper part of the filter housing, air enters the engine turbocharger through the air duct.
Air filter element with large filtration area.
The filter element is made of porous cardboard.
The turbocharger is mounted on the exhaust manifold and is designed to improve cylinder filling by harnessing the energy from the exhaust gases.
The turbocharger consists of a single stage compressor and a radial turbine.
The principle of operation of a turbocharger is that the exhaust gases from the cylinders under pressure enter through the exhaust manifold into the chamber of the gas turbine.
Expanding, the gases rotate the turbine wheel.
Rotation through the shaft is transferred to the compressor impeller, which sucks in air, compresses it and supplies it under pressure to the engine cylinders.
The turbine wheel is cast from heat-resistant alloy and welded to the shaft.
The compressor wheel is cast from an aluminum alloy and secured to the shaft with a special nut.
The turbocharger shaft bearing is lubricated with oil supplied under pressure through the pipeline from the oil pump.
From the turbocharger, the oil is drained through a pipe into the engine crankcase.
The turbocharger is equipped with gas-oil contact seals with spring rings.
On the turbine side, the O-rings are installed in the bushing groove pressed onto the rotor shaft, and on the compressor side, in the compressor bushing groove.
To increase the efficiency of the oil seal on the compressor side, the sealing ring area is separated from the active oil ejection area from the bearing by an oil slinger, which forms an additional labyrinth.
The charge air cooler (intercooler) is tubular-strip aluminum, installed below the radiator of the engine cooling system.
Before entering the engine intake pipe, the air passes through a cooler, which is connected by air ducts to the turbocharger and the intake pipe.
To make it easier to start the engine, an electric heater “A” is built into the intake manifold.
When you turn the key in the ignition lock, the heater turns on and a light on the instrument panel lights up, after it goes out, you can turn on the starter.
The throttle assembly is a body with a damper, which is electrically controlled from an electronic pedal signal.
The electronic throttle control pedal (gas pedal) is bolted to the bulkhead.