What Causes Engine Overheating and Loss of Coolant?
2 Answers
First, check if there are any leaks in the cooling system. Second, verify whether the engine cooling system's heat dissipation is functioning properly. Reasons for Coolant Spraying Out: It may be due to the quality of the coolant. Mixed alcohol or methanol-based coolants have a low boiling point, making them prone to boiling over and spraying out. If the coolant's foaming tendency does not meet standards, even if it doesn't boil over, it can accumulate a large amount of foam during circulation, leading to coolant spraying out. Functions of Automotive Coolant: Coolant is essentially the water in the car's radiator, but it is used to replace ordinary tap water. It has a high boiling point, typically around 120°C, and a freezing point that can reach -40°C to -60°C. This effectively prevents the vehicle from overheating and also protects the radiator or cooling system from damage caused by freezing in winter.
A few days ago, while helping a neighbor check their car, I encountered this exact situation—the coolant level had mysteriously dropped significantly. The most common cause is a leak in the cooling system, so focus on inspecting the radiator, hose connections, and the water pump’s sealing ring. Older cars, in particular, are prone to rubber hose degradation and seepage, sometimes leaking when hot but not when cold. A faulty pressure valve in the radiator cap is another hidden issue, as it can cause fluid to be forced into the overflow tank and spill out at high temperatures. If you notice a sweet smell while driving or spot colored puddles under the car, it’s likely an external leak. Additionally, coolant has a higher boiling point than water, so using water as a substitute will lead to earlier boiling and loss. Don’t wait until the temperature gauge spikes—get to a repair shop for a pressure test right away.
