The most common reasons a car is leaking coolant include:
- Cracked or worn-out radiator hoses that can become brittle and leak.
- Damage or corrosion to the radiator causing leaks.
- A faulty water pump with worn seals or gaskets leaking coolant.
- A blown or failed head gasket causing internal or external coolant leaks.
- Leaks from the heater core due to corrosion or damage.
- Loose or damaged hose clamps allowing coolant to escape.
- Cracks in the coolant reservoir or expansion tank.
- Other gasket failures or thermostat housing leaks.
- Physical damage to cooling system components from debris or accidents.
Coolant leaks can occur externally where you see puddles or wet spots, or internally causing engine issues such as overheating or white exhaust smoke. Leaks might also come from pressure issues like a faulty radiator cap allowing coolant to boil off or escape.
To effectively address the leak, the source must be identified, usually by inspecting hoses, radiator, water pump, reservoir, gaskets, and heater core. Routine maintenance and proper coolant replacement help prevent leaks.
