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Engine Component Description

Engine Component Description

Cylinder Block

The cylinder block is a cast iron with 4 cylinder in-line. The block has 5 crankshaft bearings with the thrust bearing located on the third bearing from the front of the engine.

Crankshaft

The crankshaft is a steel crankshaft with 8 counterweights. It is supported in 5 main journals with main bearings which have oil clearance for lubricating. The 3rd bearing of the 5 main bearing is the thrust bearing whose the crankshaft has properly axial end play. A crankshaft balancer is used to control torsional vibration.

Oil Pump

The oil pump draws engine oil from the oil pan and feeds it under pressure to the various parts of the engine. An oil strainer is mounted before the inlet of the oil pump to remove impurities which could clog or damage the oil pump or other engine components. When the crankshaft rotates, the oil pump driven gear rotates. This causes the space between the gears to constantly open and narrow, pulling oil in from the oil pan when the space opens and pumping the oil out to the engine as it narrows. At high engine speeds, the oil pump supplies a much higher amount of oil than required for lubrication of the engine. The oil pressure regulator prevents too much oil from entering the engine lubrication passages.

Oil Pan

The oil pan includes the oil suction pipe, this pipe is connected with the oil pump. The oil pan is attached at the engine block.

Turbocharger

The turbo charger is a device that supplies hot, compressed air to the engine. The turbocharger is driven by the engine's exhaust gases. This gives increased engine power. Quick compressed air from this turbo charger expands with high temperature and causes decreasing of charging efficiency into the cylinder because density of oxygen gets lower. However charging efficiency into the cylinder increases as compressed hot air is cooled and density of air gets higher through the charge air cooler. It brings also higher fuel efficiency as well as lower CO2 emissions. The charge-air cooler is mounted above the radiator at the front of the car. It cools the compressed charge air with the air that is forced through the radiator by the car's forward motion.

Cylinder Head Assembly

This cylinder head is double over head camshaft (DOHC) type and has 2 camshafts that open 4 valves per cylinder with the finger followers with roller type and the valve bridges. The camshaft sprocket wheel is installed in front of the camshaft. Because of the cam follower of the hydraulic type, it does not need to adjust of valve clearance. The cylinder head is made of cast aluminum alloy for better strength in hardness with light weight. The combustion chamber of plate type of the cylinder head is designed for increasing of squish and swirl efficiency and then this is maximized to diesel combustion efficiency.

Valves

There are 2 intake and 2 exhaust valves per cylinder with "mini-lash" hydraulic tappets and rocker arms with roller bearings.

Camshaft

Two camshafts are used, one for all intake valves, the other for all exhaust valves. The camshafts are cast iron. The second camshaft is driven by a cam to cam gear.

Valve Lash Adjusters

The valve train uses a roller finger follower acted on by a hydraulic lash adjuster. The roller finger follower reduces friction and noise.

Camshaft Drive

A timing belt is used for camshaft drive. There is a tensioner to control the tension of the belt.

Intake manifold

After passing through the throttle body the air flow is directed into the combustion chambers by the intake manifold. The design of the manifold affects the engine's torque, power, noise levels, driving characteristics, exhaust emissions and fuel economy. It is made of plastic for better strength in hardness with light.

Engine Exhaust Manifold

The exhaust manifold is located to the cylinder head and send the turbocharger the exhaust gas out of the combustion chamber. It is designed to endure on high pressure and high temperature.

Positive Crankcase Ventilation System

The PCV valve carries the blow-by gas to the turbocharger inlet of the intake system. According to the engine conditions, driving conditions and the pressure of turbocharger, it is different from the amount of blow-by gas. So, the PCV valve controls the amount of blow-by gas.

Piezo Fuel Injection System

The fuel injection occurs by a common rail system of the third generation. The fuel pressure goes up to 2000 bar. The piezo fuel injection system is piloted by a closed loop combustion control.