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Why the Simple Head Gasket Has a Crucial Role to Play

When you look at a fully assembled car engine it's hard to understand the complexity within. The engine itself is actually a dozen or so individual components bolted together, and each component is usually separated by a protection device known as a gasket. Some of these gaskets are arguably more important than others, and at the top of the list is the head gasket, which separates the cylinder head from the main block of the engine. Why is this part so important?

Relying on the Head Gasket

As you may know, the internal combustion engine relies on explosive compression when air, fuel and electricity combine. This action takes place in the cylinder head, and the explosion will force each piston down through the block to rotate the main crankshaft. As you can imagine, this leads to a considerable buildup of heat, and water has to be pumped through channels within the engine to compensate for this. Consequently, cooling water is never very far away from lubricating oil or fuel for that matter, and the head gasket plays a crucial role in segregation.

Consequences of Failure

If the head gasket were to fail, as sometimes happens, cool water can leak into some of the oil channels or, in the worst-case scenario, into the cylinders themselves. This can cause a range of problems which may not be readily apparent, but which may nevertheless aggregate with time.

Cylinder Head Issues

Whenever normal operation is compromised, you can expect a knock-on effect. As the coolant is not doing its job, the entire engine may overheat, and one of the first signs may be a warped or cracked cylinder head. It's often very difficult to detect a head crack with the human eye, but it's nevertheless a major problem. If you suspect this to be the case, then the engine will need to be disassembled and special testing performed on the cylinder head itself by a professional technician.

What to Look Out For

You can sometimes tell if a head gasket has blown by looking for signs of coolant on the outside of the engine and near to the exhaust gasket. If you're constantly having to top up the coolant with no obvious signs of leakage, this is another tell-tale sign. Alternatively, you can look at the texture of the oil by checking the dipstick, and if it has a 'milky' consistency, talk to your mechanic.

Action Plan

To try and avoid problems, the engine should be maintained on a regular basis and its gaskets checked for performance. It's important to take swift action if a compromise is suspected, as otherwise the engine could fail completely. Contact a mechanic to learn more about cylinder head service.