How Does Cylinder Head Skimming Work?

Cylinder head skimming is done to reduce problems caused by engine overheating. When engines overheat, whether from a radiator leak or a water pump malfunction, the cylinder head can distort. At this point, repairing the head without skimming can cause major problems down the line. Let’s take a look at cylinder head skimming as a service, why cylinder heads should be skimmed, and the three steps in our head skimming solutions:

Understanding Cylinder Head Skimming

The point where cylinder head and cylinder meet is known as the mating surface. When this surface is bumpy or uneven, there is a risk of leakage and even rupture.

Cylinder head skimming resurfaces the mating surface to ensure that it is flat, preventing leaks by sealing the head tightly. It is usually done as part of gasket repairs, as blown gaskets typically result in warped cylinder heads. The process involves pressure testing before repairs are done, which can spot any potential cracks that are not easily noticed.

In this guide, we share some more information on cylinder head skimming and explain why it is so important to avoid engine trouble.

Why Should Cylinder Heads be Skimmed?

Essentially, skimming makes sure that the cylinder head fits exactly onto the block by ensuring that the surface is flat. As we mentioned above, failing to skim cylinder heads can cause problems with your vehicle parts.

When head gaskets malfunction or overheat, they are removed from the engine block. Once the cylinder head and block are separated, it is essential to check that they are completely flat. The engine block is generally not likely to warp due to its size and the fact that it is made of steel. The head, on the other hand, can become warped. In some cases, it can even show signs of rot.

Checking the flatness is usually done with a long steel ruler or a straight edge, with flatness tested across the length and width, as well as from one corner to another. Multiple points are tested to be sure that the head is free of even the slightest distortion.

So, how does cylinder head skimming work?

1. The cylinder head is removed from the block. It is tested for flatness and skimmed if there is any indication of warping or uneven surface.
2. To skim the head, an extremely precise layer of metal is removed from the surface using a specialised machine that has the right attachment. Only the smallest amount of metal is removed to remove warping without affecting compression.
3. Once the skimming process is complete, the cylinder heads will be flat. They will be reattached to the block and your engine will run without any risk of further damage.

If your vehicle shows any signs of overheating, it is always important to get an engine damage assessment as soon as possible. Our specialists will do a comprehensive assessment to determine whether skimming is required.

We can then recondition the engine, skimming uneven heads and ensuring that all parts are back in excellent working order. Contact Eagleharm Engineering today to find out more about cylinder head skimming services and our various other vehicle services.