Why Does the Car Radiator Keep Boiling Over?
2 Answers
The reasons why a car radiator keeps boiling over are: 1. Poor engine cooling, especially in small-displacement vehicles using air conditioning in summer, which increases engine load. Long-term accumulation of dirt inside and outside the radiator affects coolant circulation and heat dissipation. 2. Insufficient coolant. Add coolant until the reservoir is half full, then start the engine and let it idle. Observe if the liquid level in the reservoir drops rapidly. If so, it indicates a leak in the cooling system. The normal operating temperature range for an engine is between 90°C and 120°C. Insufficient antifreeze, particularly in summer, can easily lead to engine overheating and other risks. Antifreeze has the characteristics of a high boiling point and low freezing point, with a boiling point around 110°C, effectively maintaining the engine at normal operating temperatures and protecting the engine.
I've been driving for over a decade and have encountered boiling coolant issues several times. The most common cause is low coolant level due to unnoticed small cracks in the radiator or hoses. On my last long trip, the temperature gauge suddenly shot up to the red line - turned out the cooling fan had stopped working because of a failed relay. If the thermostat gets stuck in the closed position, coolant just circulates within the engine without reaching the main radiator, causing immediate overheating. A failed water pump is worse as it stops the entire circulation system. Once after overheating, I found the radiator completely clogged with scale deposits. If the cylinder head gasket blows, allowing exhaust gases into the cooling system, overheating happens rapidly. It's best to stop and check when the dashboard temperature warning light comes on - prolonged high temperatures can easily destroy the engine.
