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The power supply system of diesel engines

general information

In operation of the diesel engine in its cylinders is sucked outside air, which is compressed to a high pressure. The temperature of the air as a result of adiabatic heating is raised to the level of 700-900 ?� C, flash point greater than diesel fuel. Fuel is injected into the cylinder with some advancing and ignites. Thus, the need for a spark plug is eliminated.

As with the petrol models power system consists of two paths: the fuel supply and air supply; control the operation of the system by a special electronic control module (ECM). In more detail the principle of operation of the control system diesel engine / emission control is set out in Section Self-diagnostic system the diesel models (see. Part of Engine management and emission control).

The air supply system

The main features of the design of the intake air path described in this guide are the use of a diesel engine in its turbocharger, driven rotation flow of exhaust gases, and no throttling of the inlet (typical for diesel engines equipped with pump-type distribution). An additional increase of air flow pressurization is ensured by its thermal contraction in the heat exchanger of the intercooler (Intercooler).

The design of the air intake tract of the diesel engine

1 - Air Cleaner 2 - Turbocharger	3 - Go to the exhaust system 4 - Intercooler 5 - Exhaust manifold

Turbocharger

To rotate the boost compressor is used the exhaust gas flow of the engine supplied to the turbine housing assembly - the impeller compressor planted on one shaft with a turbine wheel and its rotation compresses passing through the air cleaner air and feed it under pressure in the intake manifold of the engine. This compressor design ensures immediate response to changes in pressurization loads on the engine, directly related to the intensity of the release of the motor.

The design of the turbocharger

1 - Compressor housing 2 - Back plate 3 - Turbine housing 4 - Piston Ring 5 - Turbine 6 - Bush 7 - Central casing 1	8 - The central housing 2 9 - The central casing 3 10 - Executive stock 12 - Diaphragm assembly 13 - Actuator 14 - Rubber hose

The structure of the turbocharger includes two sensors: temperature (TA) and air pressure supercharging. Based on the analysis of data from these sensors PCM determines the amount of air entering the engine.

Intermediate cooler (Intercooler)

Included in the intake air path of the engine turbo intercooler heat exchanger is used to compensate for the effect of adiabatic heating of the charge air compressor. The heat exchanger is mounted on the outlet of the compressor while the vehicle is continuously purged ram air captured in the molded cover bonnet air intake, - while cooling compressed air, which further increases the efficiency of the pressurization system.

The heat exchanger of the intercooler pressurization system mounted at the outlet of the turbocharger.

Fuel

Fuel diesel engines is characterized by high reliability and a good faith implementation of regular maintenance procedures in compliance with the requirements of the specification of the Head of the Power supply system, motor control / emission control and exhaust system to the type of fuel used must function properly throughout the lifetime of the vehicle.

As a result of prolonged use of the internal components can wear out nozzles. Implementation of repair nozzles will properly by a qualified service center.

The basic element of a fuel path of the diesel engine models under consideration is a high pressure pump (fuel pump) of the distribution type (VE) with electronic control, performing suction of the fuel through the filter located at the rear underneath the vehicle fuel tank and dispensing it through a nozzle into a combustion chamber of the engine.

Scheme of the fuel supply system of the diesel engine

1 - Equipped with a safety valve cap fuel filler 2 - Two-way valve 3 - Fuel injectors 4 - A one-way valve 5 - Return line	6 - The atmosphere 7 - meter fuel supply 8 - the fuel return line 9 - pump 10 - Fuel filter

High pressure fuel pump (pump)

The principle of suction and compression of the fuel injection pump electronically similar to the principle used in the pumps, mechanical type. The main difference is the use of an electronic pump instead of centrifugal equalizer moments of injection of an electronic controller with cable-operated (instead of the lever).

Design of electronic distribution type injection pump

Electronic control (GE)

GE actuator attached to a camera control at the top of the high pressure pump assembly.

The electronic control fuel injection pump of the distribution type

1 - Coil 2 - Magnet 3 - Return spring 4 - Rotor	5 - Core 6 - Ball stud 7 - Val 8 - The control shaft 9 - Magnetic Filter

The basis of the operation of the regulator put the phenomenon of the emergence of the magnetic field when applied to a coil of an electric current. Tension induced field is directly proportional to the current flowing through the coil, which enables the deployment of the rotor control to the desired position developed by overcoming the return spring force - due to the rotation of the rotor is provided by controlled linear movement of the control sleeve.

The principle of operation of the regulator.

Part of the control magnetic filter protects the working chambers of the pump assembly against ingress of foreign bodies.

The valve controlling the distribution of the moments of injection (TCV)

TCV is placed between the high-pressure and low-pressure chambers and provides pressure regulation due to open when power is applied.

When power is not supplied to the valve, the chamber remains isolated. Opening TCV leads to their unification as a result of the control piston moves under the influence developed by spring force in the position of providing pressure equalization, - injection timing adjustment is performed by simultaneously turning the roller holder.

Position sensor controlled clutch (CSP)

The sensor is placed in the upper part of the regulator assembly and delivers position information ECM control sleeve, movement of which leads to turning a specific angle of the sensor due to changes in the difference in the inductances of the upper and lower coils. ECM compares the received data with a desired value and where necessary instructs to perform appropriate adjustments by changing the strength of the current flowing through the coil.

Special fixed plate compensates for temperature changes of inductance.

Control piston position sensor (TPS)

TPS is connected to a low voltage side of the dispenser, the core consists of a rod and reel, and serves to alert the ECM on the movement of the control piston, the piston -Move leads to a change in inductance of the sensor as a result of a corresponding movement of the core.

Speed sensor pump (Np)

Np sensor delivers ECM information about speed pump. The sensor is a solenoid responsive to passage past each of its magnet 4 rotating tooth signal plate. Produced by the passage of the teeth through the magnetic field of alternating current is converted into pulse signals outputted to the control unit.