What causes hoses to collapse in a cooling system?

In a cooling system, hoses can collapse due to high suction from the water pump. When the pump is operating, it creates a negative pressure (or vacuum) within the system, particularly when the engine is running and the coolant is circulating. If this suction force exceeds the structural integrity that the hose can withstand, it may lead to the hose collapsing.

This is particularly evident in situations where hoses are made of flexible materials that may not be designed to handle high suction pressures. Over time, this can lead to kinking, pinching, or a full collapse, which can severely impact the cooling system’s ability to circulate coolant effectively, potentially causing overheating or other cooling-related issues within the engine.

Understanding the mechanics of how the water pump operates and the pressures it exerts helps clarify why high suction is a significant factor in hose integrity within a cooling system.