Cylinder head cracking can result in catastrophic damage to the engine.
In some cases, cylinder head cracking may be so severe that replacing the complete engine is the only cure.
The causes of cylinder head cracking are all relatively simple and easy to prevent. Except in the case of mechanical parts failure through no fault of the operator.
The cylinder head, used in combination with a head gasket seals the cylinders of the engine.
In the case of minor cylinder head cracking, the cylinders may lose compression and misfire.
Major cracks can cause severe damage to the cylinders of the engine.
So, when replacing either the cylinder head or the head gasket, make sure that you are using the correct parts.
Even a brand new car can experience cylinder head cracking. You could have parts that have been installed incorrectly or weaknesses in the metal.
Be certain to inspect any vehicle before you purchase it to check for incorrectly installed components. This includes the cylinder head gasket, because improper installation of this vital part can cause cylinder head cracking.
Cylinder head cracking has become more common as car manufacturers use mixed metals in their engines. Many vehicles, for example, have a solid cast iron engine block but an aluminum cylinder head. These two metals expand at different rates, and this can lead to cylinder head cracking.
The most common cause of cylinder head cracking is overheating.
When a vehicle overheats, it puts stress on all of its metal components. This includes the cylinder head, which is often at the center of the heat. This can cause the head gasket to fail. Consequently, leading to cylinder head cracking as the components warp and pressure begins to leak. All drivers should properly maintain their vehicles to prevent overheating.
Don’t make it worse than it is.
Many drivers mistakenly pour cool water into the radiator when their engine overheats. This is not a good idea, because the rapid temperature change will cause cylinder head cracking due to thermal stress. In a case where the cylinder head survives overheating, the driver may inadvertently destroy it by trying to do good.
Cylinder head cracking can also be caused by localized hot spots in the engine. These usually represent a failure in some portion of the cooling system. Always make sure that hot spots are addressed, particularly if your head gasket has failed recently.
Hot spots are often caused by:
- Uneven expansion of engine parts
- Leaky hoses
- Pre-ignition in the cylinders of the engine
Keep up with general maintenance.
To prevent overheating, make sure that your radiator is filled and in good condition, with a tightly sealed rad cap. Furthermore check to be certain that your engine thermostat is in good working order, and accurately reflecting the temperature. Make sure that you have no stretched belts or leaky hoses, and that the fan is working effectively. If your engine does overheat, stop, turn off the engine, and allow it to cool completely before adding water.
Diagnosing a bad head gasket, by looking for the symptoms, can be quite misleading.
A failed head gasket is NOT a single thing. Head gaskets may fail in several different ways. Many failure types are possible, each with different symptoms. The symptoms that we may notice will depend on how and where the head gasket fails. Exhaust fumes immediately destroy inhibitors in the coolant, and set up an acid condition.
Leaking head gasket side effects.
This is bad enough, but the coolant will then conduct electricity. This will eat away at the radiator and other parts of the system from the inside.
If the coolant should also enter the cylinders the result will be a poorly running engine.
Combustion leaks in the valve area force coolant away during heavy acceleration causing excessive heat build-up. When acceleration stops, the diverted coolant rushes back to the area, resulting in internal engine damage. If the cylinder head has warped even slightly it can cause cylinder head cracking.