Warning: Cylinder Head Skimming Exposed – Don’t Make This Costly Mistake

Cylinder head skimming is a machining process that involves removing a thin layer of material from the surface of the cylinder head. It is typically performed to correct minor imperfections or distortions in the head, ensuring a proper seal between the head and the engine block. This process plays a crucial role in optimizing engine performance, reducing emissions, and extending the lifespan of the engine.

Why is Cylinder Head Skimming Necessary?

Over time, the cylinder head can become warped or distorted due to factors such as excessive heat, improper tightening, or thermal expansion. These imperfections can compromise the seal between the head and the block, leading to various issues:

• Coolant Leaks: A warped head can create gaps that allow coolant to leak out, causing overheating and engine damage.
• Compression Loss: Distortions in the head can reduce compression, resulting in poor engine performance and increased fuel consumption.
• Blowby: Combustion gases can escape past the head gasket, causing blowby and reduced engine efficiency.
• Premature Wear: A compromised seal can lead to accelerated wear on the head gasket and other engine components.

Benefits of Cylinder Head Skimming

Skimming the cylinder head provides several benefits for the engine:

• Restores Sealing Surface: It removes imperfections, ensuring a tight seal between the head and the block.
• Improves Compression: By correcting distortions, it restores the optimal compression ratio for efficient combustion.
• Reduces Emissions: A proper seal minimizes blowby and coolant leaks, reducing harmful emissions.
• Extends Engine Life: By addressing sealing issues and preventing premature wear, it prolongs the lifespan of the engine.

When is Cylinder Head Skimming Required?

Skimming is typically necessary when the cylinder head has been removed for repairs or replacement. However, it may also be recommended in the following situations:

• Overheating: If the engine has overheated, the head may have warped.
• Head Gasket Failure: A blown head gasket can indicate the need for head skimming to correct any distortions.
• Cylinder Head Warping: Signs of head warping include coolant leaks, compression loss, or blowby.
• Engine Rebuild: As part of a complete engine rebuild, head skimming ensures a clean and level sealing surface.

Cylinder Head Skimming Process

The cylinder head skimming process involves the following steps:

• Head Removal: The cylinder head is removed from the engine block.
• Cleaning: The head is thoroughly cleaned to remove any dirt or debris.
• Inspection: The head is inspected for any visible imperfections or distortions.
• Machining: The head is placed on a specialized machine that uses a precision cutting tool to remove a thin layer of material from the surface.
• Resurfacing: The skimmed surface is polished to ensure a smooth and level finish.
• Reinstallation: The skimmed head is reinstalled on the engine block with a new head gasket.

Choosing a Qualified Machinist

Selecting a qualified machinist is crucial to ensure proper cylinder head skimming. Look for a reputable shop with experience in engine rebuilding and precision machining. The machinist should have the necessary equipment and expertise to perform the skimming process accurately and effectively.

What People Want to Know

1. What is the cost of cylinder head skimming?

The cost varies depending on the size and complexity of the head, as well as the machine shop‘s rates. Typically, it ranges from $50 to $200 per head.

2. How long does cylinder head skimming take?

The process usually takes a few hours, but it can vary depending on the condition of the head and the workload of the machine shop.

3. Can I skim the cylinder head myself?

Unless you have the necessary equipment and expertise, it is not recommended to attempt cylinder head skimming yourself. Improper machining can damage the head and compromise engine performance.