Why is the clutch heavy when the air pressure is low?
2 Answers
When the air pressure is slightly low, the clutch becoming heavy is likely caused by excessive brake clearance or too many brake wheel cylinders dispersing the air pressure distribution. If the clutch feels heavy, you should check whether the clutch booster pump has air resistance or is malfunctioning. Smooth starting: Ensuring smooth car starting undoubtedly requires starting the engine before the car begins to move. When the car starts, it suddenly accelerates from a stationary state. If the transmission system is rigidly connected to the engine, normal starting would be impossible. This is because the car has significant inertia when transitioning from stationary to moving, and the engine generates substantial torque resistance. Smooth gear shifting: Ensuring smooth gear shifting is essential. As for the claim about wearing out the clutch plate, it needs to be viewed holistically. Some people lack reversing or maneuvering skills and avoid using the semi-clutch technique, making them prone to collisions. In such cases, the cost of paintwork and panel beating would be even higher.
I've been driving large trucks for over a decade, and when the air pressure drops slightly, the clutch becomes extremely heavy. This is often due to issues with the pneumatic assist system. The booster cylinder relies on compressed air to reduce the pressure on the clutch pedal. When the air pressure is insufficient, the assist function fails, making it difficult to press. Common causes include minor leaks in the air lines, such as loose connections or aged and cracked joints, leading to air pressure loss. Another possibility is the air compressor's inefficiency, resulting in unstable output pressure after prolonged operation. A less obvious but critical detail is a clogged air filter, which is common in dusty environments and restricts airflow. I recommend checking the air pressure gauge before each trip to ensure it's within the normal range of 6-8 bar. Regularly cleaning or replacing the filter and inspecting the line seals can prevent most issues. Never force it—prolonged strain can wear out clutch components, leading to higher repair costs.
