What is the wheel next to the engine?

[VanMalia]

There are generally five wheels on the belt of a car engine. They are the crankshaft pulley, water pump pulley, generator pulley, compressor pulley, and tensioner pulley. The functions of each wheel: Crankshaft pulley, the source of power, provides the rotation of the belt. Water pump pulley, achieves the circulation of cooling water inside the engine through rotation. Generator pulley, enables the generator to rotate and provides supplementary power to the vehicle through rotation. Compressor pulley, allows the compressor to work and supplies low-temperature refrigerant to the air conditioning system, reducing the temperature inside the car. Tensioner pulley, ensures the belt operates at the appropriate tension. The function of the timing belt: When the engine is running, the piston's stroke (up and down movement), the opening and closing of the valves (timing), and the ignition sequence (timing) must maintain "synchronous" operation under the "timing" connection.

[VanIker]

Oh, this is quite an interesting question. When I first started learning to drive, I was curious about this too. The most common component next to the engine is the crankshaft pulley, which is directly connected to the engine's crankshaft and drives other pulleys, such as the alternator pulley, air conditioning compressor pulley, and water pump pulley, via a long belt. Once the belt starts rotating, all the auxiliary equipment can function—the AC blows cold air, the fan dissipates heat, and even the alternator charges the battery. If the pulleys wear out or the belt becomes loose, the car is prone to issues, like constant strange noises or equipment failure. Once, my belt snapped while driving, causing the alternator to stop working, the battery to drain, and the car to stall. Luckily, I stopped in time. I recommend checking the belt regularly for cracks or looseness—a simple routine inspection can prevent unexpected breakdowns.

[VonEmilia]

Having driven for over twenty years, I'm all too familiar with those wheels next to the engine. The crankshaft pulley plays the leading role, driving the entire belt system to rotate other smaller wheels like the fan pulley and compressor pulley. If it malfunctions—say, the bearing fails with a squeal, the belt slips, or the fan stops causing engine overheating—it can spell serious trouble by damaging core components. I had this happen once in my younger days, and the mechanic warned that neglecting maintenance comes at a high cost. Now, during every six-month oil change, I always insist on an inspection. Replacing a pulley is affordable but crucial—don't wait until a breakdown to regret it. Keep those small wheels well-maintained, and your car will run smoothly while saving you money.

[AnthonyMarie]

The wheels near the engine primarily belong to the belt system, such as the crankshaft pulley driving the serpentine belt, which transmits power to components like the alternator and water pump. If these wheels become stuck or their bearings fail, the belt may loosen, causing the fan to stop and overheat or leading to charging issues. Unusual noises are usually warning signs, so pay attention to belt tension during maintenance to ensure safety. Although the failure rate is low, it's important not to be careless.

[DiIsaac]

Safety must be taken seriously. Those wheels next to the engine, such as the crankshaft pulley, drive critical components like the water pump and alternator. A faulty water pump can lead to engine overheating and even explosion risks, while alternator failure can drain the battery and cause the car to stall, which is extremely dangerous on highways. I've seen mechanics handle such issues, and I recommend checking under the hood monthly to inspect the belt's condition for any wear or cracks. Addressing problems early ensures peace of mind while driving.