Cylinder Block And Cylinder Head

Engine spare parts consist of many parts, including camshaft, carburetor, distributor, drain plug, engine pipes and hoses, exhaust manifold, and so on. This article is focused on cylinder block and cylinder head, both of which also belong to engine spare parts.

Cylinder block

What is a cylinder block?

The engine block structure contains the cylinders and other engine parts of an internal combustion engine, so it is also called an engine block. It is considered the heart of the engine and one of the central components of the engine. The role of the cylinder block is to support and ensure the accurate position of the moving parts such as the piston, connecting rod and crankshaft; to ensure the ventilation, cooling and lubrication of the engine; to provide various auxiliary systems, components and engine installation. The cylinder block and the upper crankcase of the automobile engine are often cast into one body, called the cylinder block-crankcase.

What are cylinder blocks made of?

Cylinder blocks play a very important role in engine oil, temperature control and engine stability. For this reason, it must be made of high quality to avoid shortcomings. Although there are various types of cylinder block produced by manufacturers and suppliers, typically gray cast iron is used to produce them. Sometimes nickel and chromium are added to improve their performance. Aluminum is used for lighter weight and improved performance. However, aluminum blocks are cast iron or steel casings. Most engine cylinder walls are designed with cast iron because of their low wear quality. Some small engines have chrome plating on their cylinder walls to reduce wear and extend their life.

Cylinder head

What is a cylinder head?

The cylinder head is usually located on top of the engine block. It serves as housing for components such as intake and exhaust valves, springs and tappets, and combustion chambers. The engine cylinder head is essential for controlling the entry and exit of air from the cylinder and the distribution of fuel. The cylinder head is also equipped with injectors and valves - it contains more moving parts than any other part of the engine. Although with less attention, the cylinder head plays a key role in the engine.

Do you need to skim cylinder head?

When a cylinder head is removed from the engine block due to gasket failure, overheating etc, it is essential to check the cylinder head and block to see if they are flat. Generally, you'll find that the engine block is fine due to the size of it and usually being made of steel, but the head may show signs of warpage or rot. The way most manufacturers recommend checking the flatness is with a long steel rule or straight edge. Check across the length, across the width of the head in various places, and also diagonally from corner to corner.

Skimming the cylinder head creates a flat surface for the cylinder head to fit perfectly on the cylinder block. It is also advisable to have the cylinder block checked as well, especially if it is an aluminum block. If the cylinder block is warped then the block will need to be skimmed. It is also a good idea to check the waterways on the face of the head for any signs of rot. It'll look like gray rusting, and if it gets too bad it can fill your cylinders with coolant.