Why does the engine make abnormal noise when the clutch is pressed?

[StLane]

The reasons why the engine makes abnormal noise when the clutch is pressed are: 1. Worn clutch disc; 2. Broken clutch pressure plate spring; 3. Loose release bearing; 4. Lack of lubricant. The solutions for abnormal engine noise when pressing the clutch are: 1. Replace the clutch disc; 2. Replace the clutch pressure plate spring; 3. Adjust the release bearing; 4. Replenish lubricant. The working principle of the clutch is: 1. When the vehicle starts, the driver presses the clutch, and the pressure plate separates from the friction disc. At this time, the pressure plate and the flywheel are completely out of contact; 2. When the vehicle is driving normally, the pressure plate is tightly pressed against the friction disc of the flywheel. At this time, the friction between the pressure plate and the friction disc is large, and relative static friction is maintained between the input shaft and the output shaft, with both rotating at the same speed.