1. Rocker arm
   Carburetor
2. Intercooler
   Bowl Prechamber Ignition

A carburetor’s purpose is mixing air and fuel for internal combustion engines in the correct ratio for combustion. Fuel injection has largely supplanted them over the recent years.

1. Turbocharger
   Valves
2. Crankshaft
   Wastegate

A crankshaft is a mechanical part of an engine that converts reciprocating motion to rotational motion or vice versa, depending on the type of the engine.

1. Fuel pump
   Spark plug
2. Water pumps
   Ki-Gass

Before the widespread adoption of electronic fuel injection, most carbureted engines used mechanical fuel pumps for transferring fuel from the fuel tank into the fuel bowls of the carburetor.

1. Engine control unit
   Rocker arm
2. Poppet valve
   Distributor

Spark-ignition internal combustion engines with a mechanically-timed ignition use distributors to properly route secondary or high voltage current from the ignition coil to the spark plugs.

1. Injection pump
   Vacuum modulator
2. Wastegate
   Oil pump

An oil pump in an internal combustion engine is used for circulating engine oil under pressure to the rotating bearings, the sliding pistons and the camshaft of the engine.

1. Air filter
   Rocker cover
2. Cylinder head
   Starter

An air filter prevents abrasive substances from entering the engine’s cylinders to stop them from causing mechanical wear and oil contamination.

1. Rocker arm
   Small end bushes
2. Cross-bolted bearing
   MAP sensor

The small end bushes are mounted in the so-called “Small end” of the connection rod. They provide relative motion of the piston to the connection rod.

1. Engine control unit
   Throttle
2. Piston
   Ignition coil

An ignition coil, also called a ‘spark coil,’ is an induction coil in the ignition system of an automobile that transforms the battery’s low voltage to the thousands of volts required to create an electric spark to ignite the fuel.

1. Turbocharger
   Radiator
2. Injection pump
   Exhaust system

Despite the fact most radiators are regularly used for heating, when it comes to internal combustion engines, radiators are used for cooling.

1. High tension leads
   Poppet valve
2. Valvetrain
   Rocker cover

A valvetrain is an assembly of components designed to open and close the intake of exhaust valves. A sequence of components transmits motion throughout the assembly.

1. Valves
   Vacuum modulator
2. Starter
   MAP sensor

A conventional reciprocating internal combustion engine uses valves to control the air/fuel admix flow in and out of the combustion chamber.

1. Starter
   Bowl Prechamber Ignition
2. Spark plug
   Piston Rings

Étienne Lenoir used an electric spark plug on his gas engine in 1860, creating the first combustion piston engine. Lenoir is credited for the invention of the first spark plug.

1. Piston
   Crankshaft
2. Rocker arm
   Carburetor

Located in the cylinder, a piston is a component of reciprocating engines made gas-tight by piston rings. It transfers force from expanding gas in the cylinder to the crankshaft.

1. Fuel pump
   MAP sensor
2. Piston Rings
   Poppet valve

A poppet valve is also called a mushroom valve, and it is typically used to control the quantity and timing of vapor or gas flow into the engine.

1. Exhaust system
   Water pumps
2. Engine control unit
   Oil pump

An engine control unit (ECU) ensures optimal engine performance by controlling series of actuators on an internal combustion engine.

1. Crankshaft
   Oil pan
2. Air filter
   High tension leads

The oil pan is a reservoir for oil that’s attached to the bottom of the engine with bolts. A pump guides the oil from the pan through a filter to remove any dirt before it sends it to circulate through the engine.

1. Wastegate
   Electronic control unit
2. Intercooler
   Cylinder head

The wastegate’s primary function is to protect the engine and the turbocharger by regulating the maximum boost pressure in turbocharger systems.

1. Radiator
   Rocker cover
2. Vacuum modulator
   High tension leads

Some cars use a vacuum modulator to apply pressure to the throttle valve. The device senses the manifold pressure, which further increases when the engine is under a bigger load.

1. Radiator
   Intake manifold
2. Cylinder head
   Turbocharger

A turbocharger’s role is to force extra compressed air into the combustion chamber and thus increase an internal combustion engine’s efficiency and power output.

1. Starter
   Valves
2. Fuel pump
   Throttle

A throttle is a valve that controls the volume of vaporized fuel delivered to the cylinders of an internal combustion engine.

1. Water pumps
   Exhaust system
2. Timing belt
   Carburetor

A timing belt, or cambelt, is an important part of an internal combustion engine. It synchronizes the rotation of the camshafts and the crankshaft so that the valves open and close at the right time.

1. MAP sensor
   Ki-Gass
2. Spark plug
   Piston Rings

A manifold absolute pressure sensor (MAP sensor) is one of the sensors used typically by engines that are fuel-injected. It is mostly seen in an internal combustion engine’s electronic control system.

1. Starter ring gear
   Ignition coil
2. High tension leads
   Intake manifold

High tension leads are the wires that connect an ignition coil, a distributor or a magneto to each of the spark plugs in many types of internal combustion engines.

1. Connecting rod bearings
   Injection pump
2. Distributor
   Piston Rings

The pump that pumps diesel fuel into the cylinders of a diesel engine is called an injection pump. It’s a very complex piece of engineering, calibrated to deliver the right quantity of fuel every time.

1. Piston
   Engine block
2. Oil pump
   Rocker arm

Rocker arms are typically placed between the intake and exhaust valves and the pushrod. The pushrod pushes up the rocker arm and therefore pushes down the valves.

1. Water pumps
   Screamer pipe
2. Valvetrain
   Poppet valve

A screamer pipe is known for the loud noise it produces. It’s a type of exhaust setup fitted to some automotive turbocharged gas engines.

1. Rocker cover
   Water pumps
2. Intercooler
   Engine control unit

The role of the intercoolers is to reduce induction air heat created by the supercharger or turbocharger and to increase the efficiency of the induction system by promoting more thorough combustion.

1. Cylinder head
   Valvetrain
2. Starter ring gear
   Fuel pump

A starter ring gear is a carbon steel ring placed at the periphery of a flywheel of an internal combustion engine. The ring has teeth that are driven by the smaller gear of the starter motor.

1. Intake manifold
   Poppet valve
2. Carburetor
   Exhaust manifold

The exhaust manifold channels exhaust gases away from the controlled combustion inside an engine.

1. Engine block
   Piston rings
2. Ignition coil
   Wastegate

Piston rings have several important functions in reciprocating engines, some of which include sealing the combustion chamber to ensure minimal loss of gases to the crankcase and improving heat transfer from the piston to the cylinder wall.

1. Cylinder head
   Ki-Gass
2. Radiator
   Carburetor

A cylinder head sits above the cylinders on top of the cylinder block in an internal combustion engine. The head closes in the top of the cylinder, forming a combustion chamber.

1. Spark plug
   Bowl Prechamber Ignition
2. Main crankshaft bearings
   Rocker cover

Main crankshaft bearings are mounted in the crankcase. The main bearing consists of two parts: upper and lower. It also has a hole for passing oil to the feed holes in the crankshaft.

1. Vacuum modulator
   Water pump
2. Oil pump
   Crankshaft

A water pump makes sure the coolant keeps moving through the engine block, hoses and radiator while maintaining an optimal operating temperature.

1. Valves
   Timing belt
2. Engine control unit
   Intake manifold

An intake manifold is a pipe that brings air or air/fuel mixture into the combustion chamber. It’s connected to the intake valves.

1. Air filter
   Turbocharger
2. Starter
   MAP sensor

Starters can be electric, pneumatic or hydraulic. In some cases, especially when it comes to very large engines, the starter can even be another internal-combustion engine.

1. Connecting rod bearing
   Radiator
2. Cross-bolted bearing
   Throttle

Connecting rod bearings have a role of providing rotation motion in the crank pin within the connecting rod. A bearing always consists of two parts that are usually interchangeable.

1. Injection pump
   Ki-Gass
2. High tension leads
   Engine block

An engine block is the main structure of an internal combustion engine that contains the cylinders and other parts. It typically consists of the cylinder, oil galleries, coolant passages, crankcase and cylinder head(s).

1. Rocker arm
   Rocker cover
2. Electronic control unit
   Bowl Prechamber Ignition

Rocker covers are bolted on over rocker arms in internal combustion engines. They are also called valve covers, but they are also sometimes referred to as a “timing cover” or a “cam cover.”