Cruze

Engine Component Description

The cylinder hollow frame structured 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.

The crankshaft is a steel crankshaft. 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 harmonic damper is used to control torsional vibration.

The Oil Pump is a Crankshaft driven oil pump integrated in pump module. The oil pump draws engine oil from the sump 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 sump 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.

The sump is a structural aluminium sump with transmission attachment. It includes the oil suction pipe, this pipe is connected with the oil pump. The sump is attached at the engine block.

The Pistons are aluminium pistons with top land and floating pin. The Connecting Rods are fractured steel connecting rods with bushes.

This cylinder head is double over head camshaft (DOHC) type and has 2 camshafts that open 4 valves per cylinder with tappets. The camshaft sprocket wheels are installed in front of the camshafts. Because of the cam follower of the hydraulic type, it does not need to adjust of valve clearance. The combustion chamber of the cylinder head is designed for increasing of squish and swirl efficiency and then this is maximised to petrol combustion efficiency.

There are 2 inlet and 2 exhaust valves with hydraulic tappets per cylinder.

Two camshafts are used, one for all inlet valves, the other for all exhaust valves. The camshafts are cast iron. The camshafts are driven by the crankshaft over the timing belt.

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

The inlet manifold is the air flow passage to the cylinder combustion chamber through the throttle body and has an effect on engine torque, power, noise, drivability, emission, fuel economy and performance. It is made of plastic for better strength in hardness with little weight. It has a change over module that steers a flap that controls the airflow over 2 ways. The long way for lower speed and more torque and the short way for high speed level and more horsepower output.

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

The crankcase ventilation system is used to consume crankcase vapours in the combustion process instead of venting vapours to the atmosphere. Fresh air from the inlet system is supplied to the crankcase, mixed with blow-by gases and then passed through a calibrated orifice into the throttle body. The primary control is through the positive crankcase ventilation (PCV) orifice which meters the flow at a rate depending on inlet vacuum. The PCV orifice is an integral part of the camshaft cover. If abnormal operating conditions occur, the system is designed to allow excessive amounts of blow-by gases to back flow through the crankcase vent into the inlet system to be consumed by normal combustion.