General information
The power an engine can produce depends on the amount of air and fuel that enters the engine cylinders. To increase engine power, it is necessary to increase the supply of air and fuel. Injecting more fuel will have no effect until there is sufficient air available for combustion. Otherwise, excess unburned fuel will form, which will lead to overheating and increased smoke in the engine. To increase the amount of air supplied to the engine, a turbocharger is used, which compresses the air entering the combustion chamber.
The turbocharger consists of a centrifugal compressor wheel and a turbine, connected to each other by a common rigid axle. Both of these elements rotate in the same direction at the same speed. The energy from the exhaust gas flow, which is not used in conventional engines, is converted into torque, which drives the turbocharger. The exhaust gases leaving the engine cylinders have high temperature and pressure. They accelerate to high speed and interact with the turbine blades, which converts kinetic energy into mechanical rotational energy. Energy conversion is accompanied by a decrease in the temperature and pressure of the exhaust gases. The turbocharger draws air through the air filter, compresses it and delivers it into the engine cylinders. By increasing the amount of air, the amount of fuel can also be increased, allowing the engine to develop more power.
To lubricate the turbocharger, engine oil is supplied under pressure through a special pipeline.
Since the turbocharger operates at high speed, care and cleanliness are required. If dirt gets into the turbocharger, it can fail.
Caution: Before disconnecting any components from the turbocharger, thoroughly clean them of any dirt. To protect against contamination, place the removed turbocharger components in a sealed container and close the turbocharger air ducts.
The turbocharger has no regulation system and provides a boost pressure of 0.5 bar at idle speed and 1 bar at full load.
It is located on the exhaust manifold above the catalytic converter and is covered by a heat shield.
Removal
Turn off the ignition and disconnect the ground wire from the battery.
Place the car on a lift.
Figure 4.37. Location of bolts (1) for fastening the upper cross panel (2) and clamps (3)
Remove bolts 1 (figure 4.37) fastening the upper cross panel 2.
Remove the 3 radiator grille retaining clips.
Lift and tilt the upper cross panel towards the front of the vehicle.
Figure 4.38. Location of bolts (1) for fastening the heat shield
Remove bolts 1 (figure 4.38) heat shield fastenings.
Protect the cooling system radiator and, moving upwards, remove the heat shield.
Remove the air duct and the turbocharger receiver-damper.
Remove the upper exhaust manifold heat shield.
Figure 4.39. Turbocharger: 1 - catalytic converter; 2 - clamp; 3 - turbocharger; 4 - exhaust manifold; 5 - nuts
Loosen clamp 2 (figure 4.39) fastening the catalytic converter 1 to the turbocharger 3.
Remove the hollow bolt to lubricate the turbocharger.
Remove the turbocharger oil return connection.
Unscrew nuts 5 securing the turbocharger to the exhaust manifold 4 and remove the turbocharger.
Installation
Clean the surface of the exhaust manifold.
Install the turbocharger onto the exhaust manifold and secure it with new nuts, tightening them to a torque of 25 Nm.
Replace the leather gasket of the hollow bolt used to lubricate the turbocharger.
Install the oil feed pipe with the hollow bolt.
Tighten the hollow bolt to 30 Nm.
Install the turbocharger oil return connection.
Connect the catalytic converter to the turbocharger and secure it with a clamp.
Install the exhaust manifold upper heat shield and secure with bolts, tightening them to a torque of 10 Nm.
Install the air duct and the turbocharger receiver-damper.
Protect the cooling system radiator and install a heat shield from above. Tighten the heat shield mounting bolts to 5 Nm.
Install the top cross panel.
Install the radiator grille retainers.
Tighten the upper cross panel mounting bolts to 15 Nm.
Connect the cable to the negative terminal of the battery.