Why Are Cylinder Sleeves Used and Why to Sleeve Cylinders?
A cylinder sleeve, sometimes also known as a cylinder liner, is installed to prevent the damage of the walls of the cylinder inside an engine block. Let us understand a few reasons why cylinders are sleeved. Why Sleeve An Engine? The primary reason is, as stated above, to repair the damage done to a cylinder. Additionally, Cylinder sleeves are also installed to restore the bore size of a cylinder if it has been bored out with usage, if it is cracked, or needs any other kind of repair. Sometimes, cylinders are overbored in order to increase their displacement. Cylinder sleeves are more common in diesel engines than in gasoline engines, but sometimes, a gasoline engine may also be sleeved under certain circumstances. Sleeving a cylinder, over boring it out, and replacing the piston and the piston ring is better as it saves a lot of time and money. Sometimes, engine blocks are too thin and boring them out becomes impossible without cylinder sleeves. For the Modification of Performance Sleeves offer a number of advantages for high-performance applications. The distance between the bore centers of a cylinder and the thickness of the castings is
what limits the displacement of an engine. If the cylinder has thick walls, then it can be bored out to increase the displacement. If you are boring out the cylinder to improve displacement, removing too much of the walls will cause more harm than helping it. This can be overcome by converting to a wet sleeve. Here, the existing sleeves are removed and the wet sleeves are put in their places. With a wet cylinder sleeve, the coolant is in constant touch with the walls, making it better equipped to handle higher horsepower demands. This, in turn, improves the displacement of the engine considerably. Why Are Wet Sleeves Better? A dry sleeve is cast onto the walls of the cylinder and is not in direct contact with the coolant. It is actually installed into the cooling jacket in the cylinder wall instead. However, a wet sleeve comes in direct contact with the coolant at all times and has much thicker walls as compared to dry sleeves, since they also need to prevent the leakage of the coolant inside. Wet sleeves can be manufactured to have water jackets or have a coolant or water gap. Since the coolant is always in constant touch, it is able to maintain an even level of temperature and pressure than a dry sleeve would be able to do. Tips on Installing a Dry Sleeve An important decision to be made about installing a dry sleeve is the interference of the cylinder sleeve that is right for the application. Aluminum blocks require a bigger interference than a cast iron cylinder block. For water-cooled sleeves, the general recommendation for the interference is about .0015’’ to .002’’. The measurement of cylinder sleeves is done by measuring the outer diameter and the inner diameter of the cylinder before the installation is done. It is recommended that the cylinder is honed with 280 grit stones so that the process of installation becomes easier. The sleeve is installed by having the cylinder heated to a high temperature in an oven so that it expands evenly and the sleeve is chilled or frozen in order to contract it.
Then, the two are fitted together and aligned properly before it is allowed to cool. It is important to note that it should not be under any circumstance beaten with a hammer. Cylinder sleeves in India are manufactured according to the recent demands for efficiency and fuel conservation, making it possible to achieve better performance from engine blocks.
Source: Why Are Cylinder Sleeves Used and Why to Sleeve Cylinders