What Are Some Causes of an Engine Coolant Leak?

causes-engine-coolant-leak Credit: Getty Images North America/Getty Images News/Getty Images

Blown head gaskets and broken hoses can cause engine coolant leaks. A cracked engine head or block can also cause the leaks.

A blown head gasket is often caused by overheating of the engine. Once the engine overheats and the gasket fails, coolant leaks into the crankcase, which affects the oil and the spark plugs. This issue is commonly diagnosed by a mechanic through specific tests, including hydrocarbon coolant testing. When the head gasket fails, it can cause the car to misfire and, if not repaired, it can cause catastrophic damage to the engine.

Leaking hoses or worn seals can lead to engine coolant leaks. This is diagnosed by determining the hose that leaks and replacing it with one approved by the manufacturer. To find the hose that is leaking, users should turn the vehicle on and watch under the hood to pinpoint where the coolant is leaking from.

When the engine head or block becomes cracked, coolant leaks into the cylinder, which causes it to mix with the oil. After time, the leak causes damage to the pistons and bearings, which leads to expensive repairs. This can also be diagnosed through various types of coolant testing, including dye tests performed by certified mechanics.