How to Recognize a Faulty Cylinder Head Gasket?

In this new article dedicated to vehicle maintenance, we’ll talk about the infamous cylinder head gasket, which is located between the engine block (pistons and cylinders) and the cylinder head (valves, spark plugs and other components). Problems occurring there are not uncommon and it’s good to know what the symptoms are.

But before going any further, what exactly is the purpose of the cylinder head gasket? In short, it’s the part that seals the combustion chamber to create the compression needed to generate power. It also prevents the motor oil and cooling fluid from leaking and causing overheating in that area. Among all engine gaskets, it’s the one that’s working the hardest, and therefore the most likely to fail.

And since automakers turn to increasingly small engines, the cylinder head gaskets also diminish in size and strength, which makes them more susceptible to failure.

4 Signs of a Failed Cylinder Head Gasket

A faulty head gasket can let motor oil, cooling fluid or fuel into the combustion chamber, leading to improper engine operation and possible damage. In order to prevent that, pay attention to these signs:

1. Coloured Smoke: Cooling fluid leaking into the combustion chamber will generally produce white smoke. If it’s engine oil, the exhaust will let out blue smoke.

2. Low Fluid Levels: A faulty head gasket can cause motor oil or cooling fluid leaks between the coolant or fuel circuit and the outside of the engine. This could cause your fluid tanks to show low levels, so beware.

3. Power Loss: The cylinders’ compression will be reduced if the head gasket is damaged and allows the air/fuel mix to escape. This compression loss will inevitably cause the engine to malfunction and lose power.

4. Discoloured Oil: When it breaks or does not function properly, a cylinder head gasket can cause the cooling fluid to mix with the engine oil. If the latter shows a lighter or milky colour, it’s generally a sign that the cooling fluid is leaking into the combustion chambers.

In any case, you should bring your vehicle to a repair shop as soon as possible to solve the problem and prevent more serious consequences. Note that a failed head gasket is pretty expensive to replace because of the hours of labour that will be billed.