40 Essential Parts of a Car Engine

A modern internal-combustion car engine is built from core components such as the engine block, pistons, crankshaft, camshaft, valves, timing system, intake and exhaust manifolds, fuel injectors, spark plugs, and vital oil and coolant pumps; below is a concise list of 40 widely recognized engine parts that together make the engine run.

The 40 engine parts that matter

The following list groups the most commonly referenced mechanical, air/fuel, ignition, lubrication, and cooling components you’ll encounter in a typical gasoline-powered, four-stroke car engine. While specific designs vary by make, model, and fuel type, these parts represent the mainstream foundation of engine construction and operation.

1. Engine block — the main structure housing cylinders and internal passages
2. Cylinder — the precision bore where the piston travels
3. Piston — moves up and down to convert combustion pressure into motion
4. Piston rings — seal the piston to the cylinder and control oil
5. Wrist pin (gudgeon pin) — connects the piston to the connecting rod
6. Connecting rod — links piston motion to the crankshaft
7. Crankshaft — converts reciprocating motion into rotational power
8. Main bearings — support the crankshaft in the block
9. Rod bearings — allow the connecting rod to pivot on the crankshaft
10. Harmonic balancer (crank damper) — reduces torsional vibration on the crank
11. Flywheel (or flexplate) — stores rotational energy; interfaces with the clutch/torque converter
12. Cylinder head — contains combustion chambers, ports, and valvetrain
13. Head gasket — seals the block-to-head interface
14. Intake valves — admit the air/fuel charge into the cylinder
15. Exhaust valves — release spent gases from the cylinder
16. Valve springs — close valves and control valve motion
17. Valve stem seals — prevent oil from entering the combustion chamber
18. Valve guides — support valve stems for accurate travel
19. Camshaft — controls valve timing and lift
20. Valve cover (cam/rocker cover) — encloses the top of the head and valvetrain
21. Rocker arms (or cam followers) — transfer cam motion to the valves
22. Lifters/tappets (hydraulic or solid) — interface between cam lobes and pushrods/valves
23. Pushrods (in OHV engines) — transmit motion from lifters to rockers
24. Timing belt/chain — synchronizes crankshaft and camshaft(s)
25. Timing gears/sprockets — drive the belt/chain
26. Timing tensioner — maintains correct belt/chain tension
27. Timing guides — guide and stabilize the chain/belt path
28. Intake manifold — distributes air (or air/fuel) to the cylinders
29. Throttle body — controls airflow into the engine
30. Fuel injectors — meter and spray fuel into the intake port or cylinder
31. Fuel rail — supplies pressurized fuel to the injectors
32. Spark plugs (gasoline engines) — ignite the air/fuel mixture
33. Ignition coils — generate high voltage for the spark plugs
34. Exhaust manifold — channels exhaust gases from the cylinders
35. Thermostat — regulates coolant flow to maintain engine temperature
36. PCV valve (positive crankcase ventilation) — vents blow-by gases safely
37. Oil pump — circulates engine oil under pressure
38. Oil pan (sump) — stores engine oil at the bottom of the block
39. Oil filter — removes contaminants from circulating oil
40. Water pump — circulates coolant through the engine and heater core

Together, these 40 parts form the core architecture of a contemporary internal-combustion engine, from the bottom-end rotating assembly and valvetrain to the systems that deliver fuel, spark, lubrication, and cooling.

How these parts work together

The bottom end—block, crankshaft, pistons, rods, and bearings—converts combustion pressure into smooth, usable rotation. The top end—head, valves, springs, camshaft, rockers, and related hardware—controls the timing and amount of air entering and exhaust leaving each cylinder.

The timing set keeps the camshaft(s) locked in precise synchronization with the crankshaft, ensuring valves open and close at the right moments. Air and fuel arrive via the air intake, throttle body, injectors, and intake manifold; ignition coils and spark plugs then light the compressed mixture. Exhaust gases exit through the exhaust manifold, while PCV manages crankcase vapors to maintain efficiency and reduce emissions.

Supporting it all, the oil pump, pan, and filter deliver pressurized lubrication to bearings and valvetrain, reducing wear and heat. The water pump and thermostat regulate temperature by moving coolant and holding it near the optimal operating range—critical for performance, longevity, and emissions control.

Design variations to know

Specific engines can differ: pushrod (OHV) engines use lifters and pushrods, while overhead-cam (SOHC/DOHC) designs often employ cam followers or direct-acting tappets and may omit pushrods. Diesel engines replace spark plugs with glow plugs and rely on high compression for ignition; some gasoline engines employ direct injection, placing injectors in the combustion chamber rather than the intake ports. Turbochargers and superchargers, while common today, are add-on systems and not listed here as core parts, though they integrate closely with the intake and exhaust paths.

Summary

A car engine is an integrated system of 40 foundational parts that manage air, fuel, spark, motion, lubrication, and heat. From the engine block and rotating assembly to the valvetrain, timing set, intake and exhaust, and vital oil and coolant circuits, each component plays a precise role in turning chemical energy into reliable, controlled power on the road.

What are the 40 basic parts of the engine?

The different parts that make up your car’s engine consist of: the engine block (cylinder block), combustion chamber, cylinder head, pistons, crankshaft, camshaft, timing chain, valve train, valves, rocker’s arms, pushrods/lifters, fuel injectors, and spark plugs.

What are the parts of the car engine?

An Overview of Car Engine Parts

• Crankshaft.
• Engine Block.
• Cylinder Head.
• Pistons.
• Piston Rings.
• Valves.
• Spark Plugs.
• Flywheel.

What are the engine 10 parts called?

10 Engine parts all car owners should know

• Engine Block. The engine block is the backbone of your vehicle’s engine.
• Pistons. A piston is a cylindrical-shaped component that fits inside the cylinder to form a movable boundary.
• Piston Rings.
• Crankshaft.
• Camshaft.
• Flywheel.
• Spark Plugs.
• Sump.

How many parts are there in a car engine?

A car engine contains anywhere from a couple hundred to over 2,000 parts, depending on the complexity of the engine design and whether you count every single nut, bolt, and washer. Major components include the engine block, cylinder head, pistons, crankshaft, camshaft, valves, and timing system, along with countless smaller parts that make the engine function.
 
Factors influencing the number of parts

• Engine complexity: More sophisticated engines with features like turbochargers or variable valve timing will have more components. 
• Definition of “part”: Simply counting major components like the block and head is different from counting every single screw, bearing, seal, and connecting rod within those components. 
• Engine size: Engines with more cylinders, such as V8 or W16 engines, naturally have more pistons, valves, and related parts. 

Examples of main components

• Engine Block: The foundation of the engine, housing the cylinders. 
• Cylinder Head: Sits on top of the block and contains valves, spark plugs, and combustion chambers. 
• Pistons: Move up and down inside the cylinders to compress the fuel-air mixture. 
• Crankshaft: Converts the pistons’ linear motion into rotational movement to power the vehicle. 
• Valves: Control the flow of air and fuel into the cylinders and exhaust gases out of them. 
• Timing System: Components like the timing belt or chain, pulleys, and gears that synchronize the engine’s movements.