What are the Different Parts of an IC Engine?
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What are the Different Parts of an IC Engine?

There are Different Parts of an IC Engine. Internal combustion engines or IC Engines have a number of parts which are given below:

Different Parts of an IC Engine

Different Parts of an I.C Engine
Different Parts of an I.C Engine


The cylinder is the main and very basic part of an engine which confines expanding gases and forms a combustion space. In a cylinder there is a piston which slides up and down movement and in this cylinder, the piston operates to suck the air or air-fuel mixture and this mixture is compressed by the piston in the cylinder and then the gas is allowed to expand transmitting power for the useful work. All these activities are happening in the cylinder only. Cylinders are made of high-grade cast iron usually in a single piece. These cylinders are maybe air-cooled or water-cooled.

Cylinder Block

A cylinder block is defined as the solid casting body which includes the cylinder and the cooling fans in case of air cold engines and a water jacket in case of water-cooled engines.

Cylinder Head

The cylinder head is the detachable portion of an engine which covers the cylinder and includes spark plugs, valves and injectors. The cylinder head usually contains the inlet valve for admitting the mixture of Air or an air-fuel mixture and the exhaust valve for discharging the gases that come through the combustion.

These inlet and exhaust valves are close by the cams that are connected to the crankshaft. The pipes which are connected with the inner parts of the cylinder to a common intake for the engine are called the inlet manifold and if the exhaust pipes are similarly connected to a common exhaust system then the piping is called the exhaust manifold. The cylinder head is made of cast iron or aluminium.


A piston is a cylindrical part which is closed at the one and is connected to the connecting rod by a piston pin. The piston should have the following properties like

  • It should slide freely
  • It should be light
  • And it should be strong

Pistons are made of cast iron due to their high compressive strength or aluminium alloy due to their lightness.

The top of the piston is called the head or crown of the piston.

The skirt is that portion of the piston below the piston pin which is generally designed to absorb the side movement of the piston.

Piston Ring

A piston ring is a split expansion ring that is placed in the group of the piston. A piston ring is usually made of steel alloy or cast iron.

Compression Ring

Compression rings are generally single-piece plans and placed in the groups of the piston nearest to the piston head. Compression rings are used to prevent the leakage of gases from the cylinder and does help increase the compression pressure inside the cylinder.

Oil Ring

Oil rings are located either in the lowest group above the piston pin or in the group above the piston skirt. They control the distribution of the lubrication oil in the piston and in the cylinder.

Piston Pin

A piston pin is used to join the connecting rod to the piston and it is also called a wrist pin or gudgeon pin.

Connecting rod

Connecting rods one and its attached to the crankshaft and other and is attached to the piston. It transmits the power of combustion to the crankshaft and does making it rotate continuously. Connecting rods are usually made of drop forged Steel.


The crankshaft is the main shaft on the engine that converts the reciprocating motion of the piston into the rotary motion of the flywheel. The space that supports the crankshaft in the surrender block is called the main journal and the part to which connecting rod is attached is known as the crank journal. It is made of drop-forged steel or cast steel.


The flywheel plays an important role in the engine and it is made of cast iron. The flywheel has the following functions.

  • Flywheel strokes the energy during the power stroke and gives it back during the ideal strokes.
  • Helps in adjusting the timing of the engine.
  • Sometimes the fly will the purpose of a Pulley for the transmitting power.


The crankcase is the part of the engine which supports and encloses the camshaft and the crankshaft. It provides the reservoir for the lubrication oil. There are many accessories mounting on it such as an oil pump, starter motor, ignition components and oil filter. A crankcase is generally made of cast iron or cast aluminium.

Timing Gears

Timing gears are the combination of gears, in which one gear is a mountain at the one end of the camshaft and the other is a mountain at the other end of the crankshaft. These are the timing gears which control the timing of opening and closing of the valves and fuel injection timing.


A camshaft is a shaft which raises and lowers the inlet and exhaust valves at proper times. These are generally connected by the crankshaft by means of gears, chains or sprockets.

Also Read, 4 Stroke Engine Working Principle, Diagram | Four Stroke Engine

Frequently Asked Questions related to Different Parts of an IC Engine

1. What are the 5 main parts of an engine?

The main parts of an engine are the cylinder, cylinder head, piston, crankshaft and camshaft. There are many other parts as well which has explained in the article.

2. What are the engine parts of car?

A car engine has many parts, a few of them are cylinder, cylinder head, piston, crankshaft and camshaft, piston ring, piston rod, inlet valve, exhaust valve, spark plug in case of a petrol engine, flywheel, crankcase, compression ring etc.