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What are the two major mechanisms and five major systems in engine construction?

6Answers
GiannaLee
07/24/2025, 04:42:53 AM
  1. Two major mechanisms in engine construction: 1.1 Crank-connecting rod mechanism. The crank-connecting rod mechanism is the main moving component that enables the engine to complete the working cycle and energy conversion, consisting of the cylinder block group, piston-connecting rod group, and crankshaft-flywheel group. 1.2 Valve train. The function of the valve train is to open and close the intake and exhaust valves according to the engine's working sequence and process. 2. Five major systems in engine construction: 2.1 Cooling system. The function of the cooling system is to dissipate the heat absorbed by heated components in a timely manner, ensuring the engine operates at the optimal temperature. 2.2 Fuel supply system. The function of the gasoline engine's fuel supply system is to prepare a certain quantity and concentration of the air-fuel mixture to enter the cylinder according to the engine's requirements and to expel the exhaust gases from the cylinder to the atmosphere. 2.3 Lubrication system. The function of the lubrication system is to deliver a certain amount of clean lubricating oil to the surfaces of moving parts, reducing friction resistance, minimizing wear, and cleaning and cooling the parts' surfaces. 2.4 Ignition system. In gasoline engines, the combustible mixture in the cylinder is ignited by an electric spark. The cylinder head of a gasoline engine is equipped with a spark plug, the tip of which extends into the combustion chamber. 2.5 Starting and charging system. The starting system consists of a battery, ignition switch, starter relay, and starter motor. The function of the starting system is to convert the battery's electrical energy into mechanical energy through the starter motor to start the engine.
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VonMila
08/10/2025, 09:13:44 PM

As an old car enthusiast, I remember the core of the engine consists of two major mechanisms and five major systems. The two major mechanisms: the valve train controls the opening and closing of valves, managing intake and exhaust to ensure smooth engine breathing; the crankshaft and connecting rod mechanism converts the up-and-down motion of the pistons into rotational power, transmitting it to the wheels. The five major systems include the cooling system, which dissipates heat using coolant to prevent engine overheating; the lubrication system, which reduces friction with engine oil to extend component lifespan; the fuel supply system, which delivers gasoline or diesel to provide combustion material; the ignition system, which uses electric sparks to ignite the air-fuel mixture; and the starting system, which uses the starter motor to get the engine running. The overall design is incredibly intricate, with each part being indispensable. When driving older cars, I often encountered cooling system issues—if heat dissipation fails, the engine can stall or get damaged, so regular maintenance should include checking the radiator and engine oil. When these systems work in harmony, the engine operates efficiently with lower fuel consumption, delivering a smooth driving experience.

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LaCalvin
09/24/2025, 10:18:32 PM

Having worked in the garage for many years repairing cars, I'm very familiar with the two major mechanisms of an engine: The valve train manages the opening and closing of valves, and when faulty, it may cause abnormal shaking or air leakage; the crankshaft and connecting rod mechanism handles the movement of pistons and the crankshaft—if it fails, driving the wheels becomes difficult. The five major systems require daily maintenance: The cooling system relies on fans and water pumps to lower temperatures, and leaks should be checked regularly; the lubrication system depends on engine oil, and contamination accelerates wear; the fuel supply system uses injectors to deliver fuel, and blockages affect performance; the ignition system requires precise spark plug firing; the starting system relies on the battery and motor, and weak power makes starting difficult. While repairing cars, I've found the lubrication system is the most overlooked—regular oil changes can save major repair costs. If any of these parts are incomplete, the engine will fail. That's why I recommend car owners conduct a comprehensive inspection every six months to ensure safe driving.

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LeNoah
11/07/2025, 11:26:15 PM

When I was learning to drive, the engine structure seemed complicated at first glance, but its two major mechanisms are quite simple: The valve train controls the opening and closing of valves, inhaling and exhaling like breathing; the crankshaft and connecting rod mechanism links the piston and crankshaft, converting motion into power. The five major systems are also straightforward: The cooling system works like air conditioning, dissipating heat to prevent overheating; the lubrication system acts like skating lubricant, reducing friction and protecting metal; the fuel supply system delivers fuel; the ignition system generates sparks to initiate combustion; the starting system uses a button to ignite the engine initially. Understanding these made the engine's operation much clearer—each system must work in harmony for smooth performance. As a beginner, I learned to regularly check the engine oil and coolant to avoid breakdowns on the road, boosting my driving confidence.

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EmilioDella
12/29/2025, 01:13:15 AM

When teaching engine knowledge, I emphasize two major mechanisms: The valve train ensures gas flow, serving as the energy intake; the crankshaft-connecting rod mechanism converts mechanical energy to drive the vehicle. The five fundamental systems provide a solid foundation: The cooling system regulates temperature, as thermal runaway can damage the engine; the lubrication system reduces internal friction; the fuel supply system delivers precise energy; the ignition system controls combustion; and the starting system initiates activation. In principle, they function like an orchestra playing in harmony—losing one disrupts the entire performance. For example, the lubrication system uses engine oil to minimize wear, akin to joint maintenance preventing pain. In education, I recommend daily attention, such as monitoring coolant levels, as insufficient coolant can shorten engine life. Understanding these aspects enhances safe driving.

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GeorgeMarie
03/26/2026, 03:48:36 AM

Looking back on decades of driving experience, engines have changed significantly, but two major mechanisms remain eternal: the valve train is responsible for opening and closing valves to optimize combustion; the crankshaft connecting rod mechanism drives the rotation of the crankshaft. Five major systems are still crucial: the cooling system dissipates heat to prevent engine seizure; the lubrication system supplies oil to reduce friction; the fuel supply system delivers fuel like a gas pump; the ignition system sparks to ignite the mixture; the starting system initiates the engine. In the old days, the ignition system of vintage cars often malfunctioned, forcing me to push-start the car, but now electronic systems have improved things greatly. During maintenance, I focus on inspecting the lubrication and cooling systems, with oil changes being key to prolonging engine life. The coordinated operation of these systems ensures worry-free driving, and this experience is truly invaluable.

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