The document describes the basic parts of an internal combustion engine. It lists 33 main parts, including the cylinder block, cylinder head, piston, connecting rod, crankshaft, camshaft, valves, manifold, flywheel, bearings, and other core components. It provides a brief description of the function of each part and how they interact to convert fuel combustion into rotational motion.

2. Basic Parts of an Engine

3. Name of the parts
1. Cylinder block 12. Intake manifold 23. Gasket
2. Cylinder 13. Exhaust manifold 24. Timing gear
3. Cylinder head 14. Spark plug 25. Fuel pump
4. Cylinder liner 15. Fuel atomizer or Injector 26. Fuel filter
5. Piston 16. Carburetor 27. Oil filter
6. Piston ring
a. Oil ring
b. Compression ring
17. Valve
a. Inlet valve
b. Exhaust valve
28. Air cleaner
7. Piston or Gudgeon pin 18. Valve spring 29. Dip stick
8. Crank shaft 19. Flywheel 30. Fuel tank
9. Connecting rod 20. Bearing 31. Radiator
10. Camshaft 21. Push rod 32. Water tank
11. High pressure fuel line 22. Rocker arm 33. Silencer

4. Cylinder block
Cylinder block is the main part of the IC (Internal Combustion)
engine. It is manufactured by casting. The material used may be cast
iron or aluminum.
 Main supporting structure which
holds the other components such
as cylinder, piston.
 Cylinder head is tightly mounted
on the top of the cylinder block
with bolts and nut.

5. Cylinder
 A cylindrical shape which is machined accurately to
accommodate the piston to reciprocate. It is called a cylinder.
 Made of Cast iron and Cast steel by the process of casting to
handle all the temperature and pressure which is generated after
the combustion of fuel.
To hold the fuel and guide the
piston.
All the functions of the engine
take place inside it, such as
intake, Suction, Compression,
Combustion, Exhaust, etc.

6. Cylinder Head
The cylinder head is the top cover of the engine cylinder which
covers the cylinder from the topside.
 To seal the cylinder and
does not give a permit to air
and gas to enter and exit
from the system.

7. Cylinder Liner
The Cylinder Liner is integral to the engine block, and it is much
harder than engine block.
Serving as the inner wall of the
cylinder.
Forms a sliding surface for the
piston ring.
Prevent the piston from
wearing .
Compression gas sealing

8. Piston
A cylindrical component fitted into the cylinder is called as the
piston. It is designed in such a way that it is strong, light, and
sufficient to handle the pressure and temperature which is
generated after the combustion of fuel. The piston is made up of
cast iron or sometimes made of aluminum alloy.
Plays a crucial role in producing
the work output.
Transfers mechanical energy to
the crankshaft with the help of
connecting rod.

9. Piston Ring
Piston rings are fitted into slots on the outside diameter of the
piston . They are made up of cast iron and alloy cast iron. It is of
two types:
1. Compressor Ring (Pressure Ring)
2. Oil Controller Ring
To provide the sealing effect between the
cylinder and the piston.
Helps to overcome the friction around the
piston.
Compressor Ring transfers heat from the
piston to the cylinder line.
Oil controller ring maintain proper
lubrication.

10. Gudgeon Pin or Piston pin
Gudgeon pins connect the piston to the connecting rod at the
small end. A piston pin made hollow for light weight. It provide
the bearing support and pivot in between piston and connecting
rod.

11. Crankshaft
The crankshaft is a rotating shaft containing one or more
crankpins, that are driven by the pistons via the connecting rods. It
made by casting and forging process using the material of alloy
steel or cast iron.
Converts the reciprocating motion
of the piston into the rotary
motion to an output shaft.

12. Connecting rod
It made up of Low carbon steel, for the small engine, it is made
up of cast aluminum alloy by the manufacturing process of Heat
treatment and forging process
Connect the piston to the
crankshaft with the help of a
piston pin and crank pin.
Transmits the power from piston
to crankshaft.
Small end connect to the piston
by gudgeon pin and big end
connect to the crankshaft.

13. Cams & Camshaft
 To operate the Inlet and
outlet valves at the correct
timing, cams are provided
on the camshaft. And also
drives the ignition system.
 The camshaft is driven by
the crankshaft through
timing gears.

14. Spark Plug
 The component used to initiate the
combustion process in the spark
ignition system.
 Spark plug will be located in the
Cylinder Head.
 Spark plug will be only available in
the Spark Ignition engines only.

15. Fuel Atomizer or Injector
 The component used to
initiate the combustion
process in the compression
ignition system.
 It will be located in the
Cylinder Head.
 Used in compression
ignition engine to inject or
atomize the fuel into fine
droplets.

16. Carburetor
 A carburetor is a device that
atomizes the fuel and mixes it
with air.
 A carburetor is used in a
petrol engine.
 it is a mixing device to supply
the engine with an air-fuel
mixture.
 It is also used to reserve the
quantity of fuel supply and
maintain fuel at a constant
head.

17. Valve and Valve Spring
 Inlet and the Exhaust valves are
provided on the cylinder head
or the side of the cylinder for
regulating the charge coming
into the cylinder or
for discharging the combustion
products from the cylinder.
 Valves will be available if it is
a 4 stroke engine only. In 2
stroke engines, there are ports
available.

18. Manifold
 Made of iron.
 Two types: Intake and Exhaust manifold.
 Intake manifold is connected to inlet
valves.
 To provide air-fuel mixture into the
engine for proper combustion.
 In diesel engine intake manifold is used
for bringing only air
 Exhaust manifold is connected to exhaust
valves.
 For taking out the exhaust gases from the
combustion chamber after combustion.

19. Fly Wheel
 A Flywheel is an inertial (force) energy
storage device.
 It is mounted on the crankshaft.
 Made of cast iron.
 Absorbs mechanical energy and serves as a
reservoir during the period when the supply of
energy is more than the requirement.
 Releases it during the period when energy is
less than required.
 Sometime serves as pulley for transmitting
engine power
 Assists in engine balancing.

20. Engine Bearing
 Several Bearing is used in the
engine in which a bearing that
allows the crankshaft to rotate is
named engine bearing.
 It is made of iron.
 Used to Reducing friction
 Supporting parts of the machine
or machine elements.
 Bearing radial or thrust loads

21. Push Rod
 Pushrods are slender metal
(forged steel) rods and long in
dimensions of the size.
 Pushrod connects from the
camshaft and rocker arm.
 To convert the rotary motion of
the camshaft into the pulse
motion of the rocker arm.
 Helps to open and close the
valve.

22. Rocker arm
 A ball crank that changes radial
movement into linear movement.
 Rocker arms are generally made
of steel.
 With the help of the spinning
motion of the overhead camshaft
that opens and closes the valves
and turns it into the up-and-down
movement.

23. Gasket
• Gasket is found between the
cylinder head and cylinder
block.
• The material of gasket may be
rubber, paper, cork and metal.
• Used to control compression
pressure in the cylinder.
• Prevent leaking air or air fuel
mixture.

24. Timing Gear
• Two types: Crank gear and shaft
gear.
• The crank shaft gear is on the
end of the crank shaft.
• The cam shaft gear is on the end
of the cam shaft.
• To ensure that the valves are
opening and closing to the
correct time
• Helps to perform in vehicle’s
engine to operate smoothly

25. Fuel Pump
 A fuel pump is a component used
in many liquid-fuelled engines
(such as petrol/gasoline or diesel
engines) to transfer the fuel from
the fuel tank to the device where it
is mixed with the intake air.
 Carbureted engines often use low-
pressure (10–15 psi or 0.7–1.0 bar)
mechanical pumps.
 Direct-injection engines operate at
a much higher pressure, up to
30,000 psi (2,100 bar).

26. High pressure fuel line
 Required to deliver the fuel from
the high pressure pump to the
combustion engine without any
loss of pressure, without any
hindrance to the flow and without
impairing the functions of the fuel
injection components.
 Diesel fuel-injection systems run
in the 10,000-30,000-psi range

27. Fuel Filter
 A fuel filter is a filter used to
screens out foreign particles or
liquids from the fuel.
 Most internal combustion
engines use a fuel filter, in order
to protect the components in the
fuel system.
 Diesel engine used two types fuel
filter: primary (10 to 15 microns)
and secondary (3 to 5 microns).

28. Air Cleaner
 Made from paper, foam, carbon,
aluminum, steel, fiberglass, or
plastic.
 Prevents engine from being
damaged with dirt, dust, sand, and
other contaminants.

29. Dip stick
• It generally made of iron.
• Used for measuring level of
lubricating oil.

30. Fuel tank
 The fuel tank is the container from
which an engine draws its fuel.
 Used to store the fuel.
 Holds the fuel supply and helps
maintain its temperature at a level
below its flash point.
 Also serves as an important means
of dissipating heat from the fuel
that is returned from the engine.

31. Radiator
 A radiator is a heat exchanger
which eliminates excess heat
from the system.
 The radiator is used in engine
cooling systems for heat
transfer.
 It helps to transfer thermal
energy from one medium to
another medium for cooling
and heating purpose.

32. Silencer
• Silencer is a device fixed to the
exhaust of a engine.
• To reduce the noise produced by
the exhaust gases of the engine.
• To cool the exhaust gases by
expansion.