The internal combustion engine has a combustion chamber where fuel is burned. This creates high temperature and pressure gases that are used to do work by expanding. The main components of an internal combustion engine include the cylinder head, cylinder block, pistons, connecting rod, crankshaft, camshaft, valves, flywheel, and systems for fuel, ignition, cooling, lubrication, and filtering air. The engine uses precise timing of its components to intake, compress, combust, and exhaust the fuel-air mixture in order to efficiently convert the chemical energy of the fuel into useful mechanical work.

1. INTERNAL COMBUSTION ENGINE
By : Hamza Sudad & Saif Al-Din Ali

2. INTERNAL COMBUSTION ENGINE
The internal combustion engine
is an engine in which the
burning of a fuel occurs in a
confined space called a
combustion chamber. This
exothermic reaction of a fuel
with an oxidizer creates gases of
high temperature and pressure,
which are permitted to expand.

3. MAIN DIFFERENCE – INTERNAL & EXTERNAL COMBUSTION ENGINE
• The main difference between internal and external combustion engine is
that in internal combustion engines, the working fluid burns inside the
cylinder, whereas in external combustion engines, combustion takes
place outside the cylinder and heat is then transferred to the working
fluid.
• internal combustion engine, the working fluid consists of a combustible
fluid placed inside a cylinder. Four-stroke Diesel and petrol (gasoline)
engines are internal combustion engines. In these engines, the fluid
undergoes combustion inside the cylinder and expands.
• external combustion engine, the combustion takes place outside the
cylinder. Heat then needs to be transferred to the cylinder where work
is done. Steam engines are an example of external combustion engines

4. THE MAIN COMPONENTS FOR IC ENGINE
1. Cylinder head
2. Cylinder block
3. Pistons
4. Piston rings
5. Piston pin
6. Connecting rod
7. Crank shaft
8. Cam shaft
9. Valves
10. Fly wheel
11. Fuel system
12. Ignition system
13. Cooling system
14. Lubrication system
15. Air cleaners

5. CYLINDER HEAD
• The cylinder head is installed above the cylinder block where the top of the
combustion chamber is formed
• The cylinder head contains most parts of the combustion chamber such as
valves, spark plugs or injectors.
• It is placed between the head of cylinder and cylinder body (Gasket) to
prevent leakage of gases, water and oil and makes the sides of the asbestos
and steel or asbestos and red copper
• Made of aluminum alloy

6. (CYLINDER HEAD)

7. CYLINDER BLOCK
• A cylinder block is the structure which contains the cylinder, plus any cylinder
sleeves and coolant passages.
• The main structure of an engine typically consists of the cylinders, coolant
passages, oil galleries, crankcase and cylinder head(s)
• Wet liner cylinder blocks use cylinder walls that are entirely removable, which
fit into the block by means of special gaskets.
• Engine blocks are normally cast from either a cast iron or an aluminum alloy.
The aluminum block is much lighter in weight, and has better heat transfer to
the coolant, but iron blocks retain some advantages and continue to be used by
some manufacturers

8. ( CYLINDER BLOCK )

9. PISTON
A piston is a moving disk enclosed in a cylinder which is made gas-tight by piston rings. The disk
moves inside the cylinder as a liquid or gas inside the cylinder expands and contracts. A piston aids
in the transformation of heat energy into mechanical work and vice versa. Because of this, pistons
are a key component of heat engines

10. THE MAIN COMPONENTS OF PISTON
1. Piston Crown
Piston crown forms the lower part of the combustion chamber in IC engine. It seals the cylinder and
transmits the gas pressure to the connecting. As per the engine requirement, different types of crowns
are used.
The piston crown is subject to the high temperatures in the combustion space and the surface is liable
to be eroded/burnt away. For this reason, the material from which the crown is made must be able to
maintain its strength and resist corrosion at high temperatures. Steel, alloyed with chromium and
molybdenum is used, and some pistons have a special alloy welded onto the hottest part of the crown to
try and reduce the erosion caused by the burning fuel. The crown also carries the 4 or 5 piston ring
grooves which may be chrome plated.
It is basically has two type of shapes :
Concave shape
Convex shape

11. 2- PISTON RINGS
A piston ring is a split ring that fits into a groove on the outer
diameter of a piston in a reciprocating engine such as an
internal combustion engine or steam engine.
The main functions of piston rings in reciprocating engines are:
1. Sealing the combustion chamber so that there is minimal
loss of gases to the crank case.
2. Improving heat transfer from the piston to the cylinder
wall.
3. Maintaining the proper quantity of the oil between the
piston and the cylinder wall
4. Regulating engine oil consumption by scraping oil from the
cylinder walls back to the sump

12. 3- PISTON SKIRTS
Piston skirt is fitted in both two stroke and four stroke engines. It has different function for different
engines. In large cross head two stroke engines with uni-flow scavenging these skirts are short in
length and are fitted to act as a guide and to stabilize the position of the piston inside the liner.
It is generally made of nodular cast iron which have the following properties:
Self lubricating
Superior wear resistance

13. 4-PISTON PIN
• The Piston pin is also called Gudgeon pin ,the gudgeon pin connects the piston to the
connecting rod and provides a bearing for the connecting rod to pivot upon as the
piston moves.
• It’s a short hollow rod made of a steel alloy of high strength and hardness that may
be physically separated from both the connecting rod and piston or crosshead.

14. CONNECTING ROD
• A connecting rod is a rigid member which connects a piston to a crank or
crankshaft in a reciprocating engine. Together with the crank, it forms a simple
mechanism that converts reciprocating motion into rotating motion.
• The connecting rod is under tremendous stress from the reciprocating load
represented by the piston, actually stretching and being compressed with every
rotation
• Failure of a connecting rod is one of the most common causes of catastrophic
engine failure.
• To obtain minimal weight and high strength, connecting rods are made of the
following materials:- Micro alloyed steels - Sintered metals - High-grade
aluminum - CFRP and titanium (for high-performance engines)
• Mass-produced connecting rods are forged, cast or sintered. Forged connecting
rods exhibit a better strength-to-weight ratio and lower costs than sintered
connecting rods. Die manufacture is however comparatively expensive.

15. CONNECTING ROD

16. CRANK SHAFT
• mechanical part able to perform a conversion between reciprocating motion and rotational
motion. In a reciprocating engine, it translates reciprocating motion of the piston into
rotational motion
• received the force affecting the pistons and transferred to the bearings
• management of control gears and water pump, generator and fan
The stresses affecting the column of the attachment:
• 1 - stress of the bending.
• 2. Torsion stress depends on torque, shaft length and dimeter.
• 3- Torsional vibration depends on the column manufacturing material
• 4 - friction in the locations of bearings
Forging and casting
• Crankshafts can be forged from a steel bar usually through roll forging or cast in ductile steel

17. CRANK SHAFT

18. CAMSHAFT
A camshaft is a shaft to which a cam is fastened or of which a cam
forms an integral part
Timing - The relationship between the rotation of the camshaft and
the rotation of the crankshaft is of critical importance. Since the
valves control the flow of the air/fuel mixture intake and exhaust
gases, they must be opened and closed at the appropriate time during
the stroke of the piston. For this reason, the camshaft is connected to
the crankshaft either directly, via a gear mechanism, or indirectly via
a belt or chain called a timing belt or timing chain.

19. VALVES
• A valve is a device that regulates, directs or controls the flow of a fluid (or gas) by opening, closing,
or partially obstructing various passageways.
• Valves form an integral component of an internal combustion engine and every cylinder in an
engine at least has two of them, i.e. an intake (intake of fuel-air mixture) and an exhaust valve
(exhaust gases). A multi-valve engine can have three, four and sometimes five valves. Multi-valve
engines generally promise increased efficiencies for fuel combustion.
• the intake valve open up at the start of the suction stroke and the exhaust valves open up during
the exhaust stroke when the piston returns from BDC to TDC. The valves remain shut during
compression and power strokes.

21. FLYWHHEL
• A flywheel is a mechanical device specifically designed to efficiently store rotational
energy. Flywheels resist changes in rotational speed by their moment of inertia. The
amount of energy stored in a flywheel is proportional to the square of its rotational
speed
• a flywheel is used to smooth fast angular velocity fluctuations of the crankshaft in a
reciprocating engine
• Cast iron flywheels are used in old steam engines. Flywheels used in car engines are
made of cast or nodular iron, steel or aluminum

22. FUEL SYSTEM
• Components :-
1. Fuel Tank
2. Feed pumps
3. Fuel filter
4. Carburetor :This is the type for
getting the air/fuel mixture into the
combustion chambers.
5. Mechanical Fuel Injection

23. IGNITION SYSTEM
• An ignition system is an array of components that are all involved in the process of igniting the
air/fuel mixture in an internal combustion engine.
• Compression ignition Diesel engines ignite the fuel-air mixture by the heat of compression and
do not need a spark. They usually have glowplugs that preheat the combustion chamber to
allow starting in cold weather.

24. CAR COOLING SYSTEM

25. .
Radiator
• To cool down the engine, a coolant is passed through the engine block, where it absorbs heat
from the engine. The hot coolant is then fed into the inlet tank of the radiator (located either on
the top of the radiator, or along one side), from which it is distributed across the radiator core
through tubes to another tank on the opposite end of the radiator. As the coolant passes
through the radiator tubes on its way to the opposite tank, it transfers much of its heat to the
tubes which, in turn, transfer the heat to the fins that are lodged between each row of tubes.
The fins then release the heat to the ambient air. Fins are used to greatly increase the contact
surface of the tubes to the air, thus increasing the exchange efficiency. The cooled coolant is fed
back to the engine, and the cycle repeats
• Copper tubes and blades of aluminum

26. .
WATER OR COOLANT PUMP
• The Water pump is responsible for the flow of liquids through the cooling system, cooled
water and coolant mix from the radiator is circulated into the middle of the pump and the
centrifugal forces and spinning fins push the water and coolant mix to the outsides of the
housing. There is a outlet pipe which then pumps this water to the cylinder head and engine
block, to absorb the heat generated there. Water is then taken from the engine back to the
radiator, ready to be cooled again and continue the cycle.

27. .
RADIATOR FAN
• The Radiator Fan is used when the vehicle is in a stationary position and there will not be
enough air flowing through the radiator, as if it was in motion. With out this in place, the car
will quickly exceed optimum operating temperatures and no doubt cause broken or damage to
the engine. The fan is normally electronically operated via engine temperature sensors which
monitor potential overheating, normal activation would only be while stationary, but in
extreme conditions this will be fully automated to suit engine parameters

28. LUBRICATION SYSTEM
• The engine lubrication system is to distribute oil to the moving parts to reduce friction between
surfaces. Lubrication plays a key role in the life expectancy of an automotive engine . If the
lubricating system fail, an engine would succumb to overheating and seizing very quickly. An oil
pump is located on the bottom of the engine. The oil is pulled through a strainer, by the oil pump,
removing larger contaminants from the mass of the fluid. The oil then forced through an oil filter
under pressure to the main bearings and the oil pressure gauge. It is important to note that not all
filters perform the same. A filter’s ability to remove particles is dependent upon many factors,
including the media material (pore size, surface area and depth of filter), the differential pressure
across the media, and the flow rate across the media. From the main bearings, the oil passes into
drilled passages in the crankshaft and the big-end bearings of the connecting rod. The oil fling
dispersed by the rotating crankshaft lubricates the cylinder walls and piston-pin bearings. The
excess oil is scraped off by the scraper rings on the piston. The engine oil also lubricates camshaft
bearings and the timing chain or gears on the camshaft drive. The excess oil in the system then
drains back to the sump

29. LUBRICATION SYSTEM

30. AIR FILTER
• A particulate air filter is a device composed of fibrous or porous materials which removes solid
particulates such as dust, pollen, mold, and bacteria from the air. Filters containing an adsorbent
or catalyst such as charcoal (carbon) may also remove odors and gaseous pollutants such as
volatile organic compounds or ozone. Air filters are used in applications where air quality is
important, notably in building ventilation systems and in engines.
• Internal combustion engine air filters
• The combustion air filter prevents abrasive particulate matter from entering the engine's
cylinders, where it would cause mechanical wear and oil contamination. Most fuel injected
vehicles use a pleated paper filter element in the form of a flat panel. This filter is usually placed
inside a plastic box connected to the throttle body with duct work. Older vehicles that use
carburetors or throttle body fuel injection typically use a cylindrical air filter,