Cylinder Head Cracking – Overheating Is The Most Common Cause

Cylinder Head Cracking - Overheating Is The Most Common Cause
Cylinder Head Cracking - Overheating Is The Most Common Cause

Cylinder head cracking, can cause catastrophic damage to your engine.

And, in some cases, the crack may be so severe, that replacing the complete engine is the only cure.

But, most 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.

Major cylinder head cracking, 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.

The cylinder head, used in combination with a head gasket, seals the cylinders of the engine. In the case of minor leaks, the cylinders may lose compression, causing engine misfires.

Cylinder Head Cracking In Different Places, Can Cause Different Problems

Internal Cracks, In A Cylinder

These cracks are the easiest to find, because they usually have visible signs.

Cylinder Head Cracking
Internal Cracks, In A Cylinder

White smoke out the exhaust is a common sign. Also, engine misfires, because of coolant in the cylinder.

Internal Cracks, Not In A Cylinder

These cracks are bad, because they allow coolant to mix with engine oil. Cylinder Head Cracking, caused by too much heat.

Internal Cracks, Not In A Cylinder
Internal Cracks, Not In A Cylinder

This problem should be visible, but only if you check the dipstick, or oil filler cap. Commonly know as “white stuff” in my oil or under my oil cap.

External Cracks, Not In The Engine

These cracks allow coolant to leak on to the ground. So, you could see it under your vehicle.

Cylinder Head Cracking
External Cracks, Not In The Engine

But, if not caught in time, you will see your engine overheating and possibly causing even more damage.

Furthermore, cylinder head cracks can also leak, antifreeze, oil or even compression.


So, even a brand new car can experience, cylinder head cracking. As a result, 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 parts. This includes the cylinder head gasket. Because, wrong installation of this vital part, can cause leaks.

It 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.

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 leak. 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.

Blown Head Gasket
Head Gasket Leaks – Are By Far, Any Motorist’s Worst Nightmare

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. So, 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 engine cooling fan is working effectively.

So, if your engine does overheat, stop, turn off the engine, and allow it to cool completely, before adding water. This can also help stop, cylinder head cracking.

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. And, may result in, cylinder head cracking.

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 leaks or cylinder head cracking.

Conclusion

So, replacing the cylinder head, is sometimes your only choice. But, if you are lucky, refacing the head with a new head gasket, could do the job.

BY DANNY BENDER