Engine part descriptions
A - F
Accelerator Cable
The accelerator cable is a spring-loaded mechanical link between the gas pedal and throttle body in older vehicles. It consists of a central wire, plastic liner, metal outer housing, and plastic outer shell. The cable converts pedal movement into engine power by controlling fuel and air flow into the engine.
Air Filter
An air filter prevents dirt and debris from entering the engine while allowing airflow. A dirty filter can reduce fuel economy, cause poor performance, illuminate the check engine light, and lead to failed emissions tests. Replacing the filter according to the manufacturer’s schedule is the recommended fix.
Air Filter For Diesel Engines
An air filter for diesel engines prevents dirt and debris from entering the engine when drawing in outside air. Diesel air filters are more robust than gasoline filters to handle the larger volume of air required. They should be inspected and replaced every 12,000-15,000 km, especially in dusty areas.
Balance Shaft
The balance shaft is a component in inline-four cylinder engines designed to offset normal engine vibration. It rotates an off-center weight to counteract vibrations. Balance shafts can be gear-, chain-, or belt-driven, and if belt-driven, should be replaced when the timing belt is replaced.
Balance Shaft Belt
The balance shaft belt drives the balance shaft, which helps reduce engine vibration and noise. It’s typically made of reinforced rubber and needs periodic replacement to prevent breakage and potential engine damage.
Camshaft
The camshaft consists of a cylindrical shaft with protruding lobes. It precisely actuates valve lifters to open and close intake and exhaust valves, coordinating with piston movement and spark plug firing. A failing camshaft can cause backfiring, misfires, and tapping noises, potentially leading to severe engine damage.
Camshaft Actuator
A camshaft actuator is a mechanical or electronic device mounted on the camshaft gear that adjusts the timing of valve opening and closing. It can advance or retard the camshaft timing to optimize engine performance. Symptoms of failure include check engine light illumination, rough idle, and lack of power.
Camshaft Position Sensor
The Camshaft Position Sensor measures the speed and position of the camshaft(s) in modern engines. It provides vital data to the engine’s computer for controlling fuel injection, ignition timing, and variable valve timing. A faulty sensor can cause engine performance issues, stalling, or even prevent the car from starting.
Camshaft Seal
The camshaft seal is a mechanical oil seal located between the camshaft and cylinder head. It prevents oil leakage from behind the timing cover. When replacing the timing belt, it’s advisable to inspect and, if necessary, replace the camshaft oil seals.
Carburetor
A carburetor regulates the air-fuel mixture sent to the engine. It acts as a metering valve, mixing gasoline with air as the engine runs. Carburetors were widely used until the 1980s before being replaced by fuel injection systems.
Connecting Rod
A connecting rod links the piston to the crankshaft, translating the piston’s reciprocating motion into the crankshaft’s rotating motion. Signs of a bad connecting rod include knocking sounds, low oil pressure, excessive oil consumption, and engine overheating. Proper maintenance, especially regular oil changes, is essential to prevent connecting rod problems.
Coolant
Coolant is a mixture of antifreeze and water that circulates through the engine to prevent overheating. It transfers heat from the engine to the radiator, maintains optimal operating temperature, and provides protection against freezing and corrosion. Regular replacement is crucial to prevent system damage and maintain engine efficiency.
Coolant Additive for Diesel Engines
A specialised fluid added to the cooling system of diesel engines to prevent corrosion, cavitation, and scale buildup. It helps maintain optimal engine temperature, protects metal components, and extends the life of the cooling system.
Coolant Expansion Tank
The coolant expansion tank acts as a temporary overflow container for expanding coolant, preventing air from entering the system and allowing for proper coolant level monitoring. A failing expansion tank can lead to coolant leaks, overheating, and potential engine damage.
Cooling Fan Clutch
The cooling fan clutch is a crucial component of a vehicle’s cooling system. It regulates the speed of the engine cooling fan based on temperature, engaging when the engine is hot and disengaging when it’s cool. This helps maintain optimal engine temperature and improves fuel efficiency.
Cooling Fan Motor
The cooling fan motor is a component of a vehicle’s cooling system. It activates when the engine temperature rises, drawing air through the radiator to cool the engine coolant. This helps maintain optimal engine temperature and prevents overheating, especially during idle or slow-speed driving.
Crankcase
The crankcase is mounted between the engine block and oil pan. It supports the crankshaft, allowing it to rotate freely while transmitting power. Signs of a failing crankcase include engine oil leaks and knocking noises. Proper oil sealing procedures are essential during installation.
Crankshaft
The crankshaft converts the pistons’ up-and-down motion into rotary motion, powering the vehicle. Made of strong steel, it’s held in place by bearings and lubricated by engine oil. Signs of failure include knocking noises, low oil pressure, or engine stoppage.
Crankshaft Position Sensor
The crankshaft position sensor measures the speed and position of the crankshaft as it rotates. It provides crucial information to the car’s computer for ignition timing, fuel injection, and tachometer operation. A faulty sensor can cause various issues, including engine misfires, poor performance, and starting problems.
Crankshaft Pulley
The crankshaft pulley, also known as the harmonic balancer, is mounted on the crankshaft’s end. It turns drive belts to operate engine accessories like the alternator and air conditioning compressor. Symptoms of failure include knocking noises and non-functioning accessories. The pulley’s rubber insert can become damaged, affecting performance and timing.
Crankshaft Seal
The crankshaft seal prevents oil leakage between the crankshaft and engine block. Located at the front and rear of the crankshaft, it maintains proper oil pressure and prevents contamination. Failure can lead to oil leaks, reduced engine performance, and potential engine damage.
Cylinder Head
The cylinder head sits atop the engine block, sealing the combustion chambers. It houses valves, spark plugs, and fuel injectors, controlling the flow of air and fuel into the cylinders and the exit of exhaust gases. The cylinder head plays a vital role in engine performance and efficiency.
Diesel Engine Oil
A specialised lubricant designed for diesel engines, featuring higher viscosity and detergent additives to handle increased heat, pressure, and contaminants. It protects engine components, reduces friction, and helps maintain performance while meeting specific requirements for diesel engine operation.
Diesel Fuel Filter
The Diesel Fuel Filter removes contaminants from fuel before it reaches the fuel injection pump and injectors. It can include a water separator and drain. Symptoms of a failing filter include lack of engine power and fuel leaks. Regular replacement with high-quality filters is crucial to prevent expensive fuel system problems.
Diesel Fuel Injector
A component in diesel engines that precisely delivers and atomizes fuel into the combustion chamber under high pressure. It ensures efficient fuel combustion, optimal engine performance, and reduced emissions. Faulty injectors can cause poor fuel economy, rough idling, and decreased power output.
Diesel Fuel Pump
The diesel fuel pump delivers fuel from the tank to the engine at high pressure. It ensures proper fuel atomisation and combustion in diesel engines, contributing to efficient performance and power output.
Diesel Injection Pump
The diesel injection pump produces high fuel pressure for diesel fuel injectors. It rotates in sync with the engine, delivering precise fuel pulses to each injector. Symptoms of failure include rough running, hard starting, misfires, power loss, and excessive exhaust smoke.
Diesel Oil Filter
Removes contaminants from engine oil, protecting the engine from wear and damage. It traps particles as small as 10-40 microns, ensuring clean oil circulation. Regular replacement is essential for optimal engine performance and longevity.
Distributor
The distributor is a component of older vehicles’ ignition systems. It triggers the ignition coil, controls timing, and routes high voltage to spark plugs. Signs of a failing distributor include check engine light, starting issues, stalling, and engine misfires. Distributors were commonly used until the late 1990s.
Drive Belt Idler Pulley
The drive belt idler pulley is a component in a vehicle’s serpentine belt system. It maintains proper tension on the drive belt, ensuring smooth operation of various engine accessories like the alternator, power steering pump, and air conditioning compressor.
Drive Belt Tensioner
A component that applies the correct tension to the drive belt, ensuring proper operation of engine accessories. It comes in manual, spring, or hydraulic types. Signs of failure include squealing noises, belt slippage, and battery warning light activation. Replacement is necessary when it malfunctions.
Drive Belt Tensioner Pulley
The Drive Belt Tensioner Pulley works in conjunction with the drive belt tensioner to maintain proper tension on the drive belt. It is pushed against the belt by the tensioner, ensuring optimal performance. Signs of failure include grinding noises and belt slippage.
Drive Belt/Fan Belt
The drive belt, also known as the fan belt, powers various engine accessories like the alternator, power steering pump, water pump, and air conditioning compressor. It wraps around pulleys connected to these parts, transferring power from the engine’s crankshaft to operate them efficiently.
Engine Block
The engine block is the main body of the engine assembly, containing cylinders that house pistons and connecting rods. Signs of a failing engine block include abnormal knocking noises and oil leaks. When problems occur, engine replacement or a “short block” replacement is often recommended.
Engine Control Unit
The Engine Control Unit (ECU) is the computer that monitors and controls your car’s engine operation. It manages fuel injection, spark timing, and emissions, receiving input from various sensors. A faulty ECU can cause issues like check engine light illumination, starting problems, poor engine performance, and increased emissions.
Engine Coolant Temperature Sensor
The Engine Coolant Temperature (ECT) Sensor measures the engine’s temperature, affecting fuel delivery, ignition timing, and performance. Located in the engine block or cylinder head, it sends voltage signals to the car’s computer based on coolant temperature. A faulty ECT sensor can cause various issues, including poor fuel economy and engine overheating.
Engine Cooling System
The engine cooling system regulates the engine’s temperature, preventing overheating and ensuring optimal performance. It circulates coolant through the engine, absorbing heat, and then dissipates that heat through the radiator. This system includes the water pump, thermostat, radiator, and various hoses.
Engine Cylinder
A cylindrical chamber in an engine where fuel combustion occurs, generating power to drive the vehicle. It contains a piston that moves up and down, converting chemical energy into mechanical energy. The number of cylinders varies depending on the engine design.
Engine Oil
Engine oil is a vital lubricant that reduces friction between moving parts in an engine, preventing wear and tear. It also helps cool the engine, clean internal components, and improve fuel efficiency. Regular oil changes are essential for maintaining engine performance and longevity.
Engine Valve
An engine valve controls the flow of air into and exhaust out of a cylinder. Each cylinder has at least one intake and one exhaust valve. Symptoms of failing valves include engine misfire and excessive oil consumption.
Flex Plate
The flex plate is a metal disk in automatic transmission vehicles that connects the torque converter to the engine’s crankshaft. It features a ring gear for starter engagement and absorbs power irregularities. A bad flex plate can cause various symptoms, including unusual noises, vibrations, and engine performance issues.
Flywheel
The flywheel is a large, heavy metal disk mounted to the rear of an engine’s crankshaft in manual transmission vehicles. It stores rotational energy, smooths out cylinder firing forces, and works with the clutch to provide smooth power flow from the engine to the transmission.
Fuel Filter
The fuel filter removes impurities from the fuel supply before it reaches the engine. Located between the fuel tank and engine, it uses a pleated material to trap contaminants, ensuring clean fuel flows to the injectors and protecting the engine from damage.
Fuel Injector
An electronically controlled valve that delivers a fine mist of fuel to the engine. It’s a crucial component of modern fuel injection systems, improving efficiency and reducing emissions. Signs of failure include poor performance, rough running, hard starting, poor fuel economy, and black smoke from the exhaust.
Fuel Injector Seals
Each fuel injector has two seals – one for the fuel system connection and another for an air-tight engine seal. Bad seals can cause fuel leaks, engine vacuum leaks, and trigger the Check Engine Light. It’s recommended to replace these seals when replacing fuel injectors.
Fuel Pressure Regulator
The fuel pressure regulator controls fuel pressure as it flows to the injectors. It maintains proper pressure by routing excess fuel back to the tank in continuous return systems or by controlling pressure in-tank for return-less systems. A faulty regulator can cause various engine performance issues.
Fuel Pump
The fuel pump is responsible for pumping fuel from the tank to the engine’s fuel injectors. It is typically a DC motor mounted inside the fuel tank. A faulty fuel pump can cause various issues, including engine starting problems, lack of power, misfires, and sputtering under heavy loads.
Fuel System
The fuel system delivers fuel from the tank to the engine. It consists of various parts including the fuel tank, pump, filter, injectors, and fuel lines. This system ensures the proper mixture of fuel and air for efficient combustion and engine performance.