What Sound Does a Faulty Flywheel Make?
1 Answers
Flywheel noise refers to the dull "thud, thud" knocking sound produced by a loose magneto rotor (commonly known as the flywheel). The sound changes periodically and is more noticeable when the speed changes, especially during startup and shutdown. The higher the speed, the louder the sound becomes. Causes of flywheel noise in cars: 1. At the power output end of the crankshaft, which connects to the transmission and the working equipment. The main function of the flywheel is to store energy and inertia outside the engine's power stroke. In a four-stroke engine, only the power stroke generates energy, while the energy for intake, compression, and exhaust comes from the stored energy in the flywheel. Correction on balance: The engine's balance primarily relies on the balance weights on the crankshaft, and single-cylinder engines have dedicated balance shafts. 2. The flywheel has a large moment of inertia. Since the power strokes of each cylinder are not continuous, the engine speed fluctuates. When the engine speed increases, the flywheel's kinetic energy rises, storing energy. When the speed decreases, the flywheel releases energy. The flywheel helps reduce speed fluctuations during engine operation. 3. Mounted at the rear end of the engine crankshaft, the flywheel has rotational inertia. Its role is to store engine energy, overcome resistance from other components, and ensure smooth rotation of the crankshaft. The clutch installed on the flywheel connects the engine to the vehicle's transmission. It also engages with the starter to facilitate engine ignition. Additionally, it serves as the integration point for crankshaft position and vehicle speed sensors. 4. During the power stroke, part of the energy transmitted to the crankshaft is absorbed by the flywheel, preventing excessive crankshaft speed increase. During the exhaust, intake, and compression strokes, the flywheel releases stored energy to compensate for the work required, preventing significant speed drops. Other functions of the flywheel include acting as the driving component in friction clutches, featuring a starter ring gear on its rim for engine ignition, and marking top dead center for calibrating ignition or injection timing and adjusting valve clearance. 5. Common flywheel damages: Wear or breakage of flywheel teeth, grooves, burn marks, or cracks on the flywheel surface.
