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Valve Train Components and Functions

A valve train can be defined as virtually any engine that acts as a controller for the opening and closing of a valve, although for older models, the fuel output is managed by the injectors. As indicated by its name, the main function of the valve train is to monitor the entry and exit of the valves. For more information on what a valve train is, its functions, components, and repair options, read the article below and gain a better understanding of the valve train. If you don't have a lot of experience fixing or working on engines, the valve train of any sort of engine is a very complex design and can be overwhelming. While this article focuses on diesel engines, many of the points can also apply to other types of engines as well.

Most of the heavy duty diesel engines that are commonly used and operated with are four valve engines. What this means is that in each cylinder there are four valves, two of which include the intake valves and the other two being the exhaust. With these types of heavy duty diesel engines, the valve train can push on or raise up from the valves using various components depending on the form. It allows for air to flow into and out of the cylinder and is located in the middle of all the valves.

There are many different components that make up the valve train. Some of the components we will go over are the types you will commonly see in the market. Among these parts include the camshaft. The camshaft is a long shaft that can move through the head or the block of the engine, although this positioning is reliant on the type of engine. There are holes that are egg shaped and can be found riding along the side of the shaft. It is the shape and size of these holes the factor that determines the amount of lift. With elevated lift, the more likely the valves will stay open for longer. In turn, this permits for more air into the cylinder.

Another component that pairs with the camshaft is the camshaft follower. The cam follower is a type of bearing that is located by the holes of the camshaft. They can be found when the holes and lobes are rotating. This provides a type of surface that has very little resistance and friction. It is referred to as a follower as well as a lifter because of this resistance to friction. They can also be called tappets. There are several types of cam followers, whose configurations generally depend on how they mount to their mating part. They will be used when the cam is in the block, rather than being overhead. Another component of the valve train is the push rod. A push rod is a rod that pushes up on the rocker arm. One of those sections that is not often used in a diesel engine is push rods. They can also only be used when the cam is not overhead and in the block. It will move depending on the movement of the camshaft follower. Another job of the pushrod is to conduct oil up to the cylinder head. A pivoting lever which pushes on the stem of the valve is a rocker arm. Rocker arms are often referred to as rocker levers, or simply rockers. The rotating camshaft lobes will either push directly on the rocker arm, or on the push rods, which will perform the motion up to the rocker arm, depending on the type of valve train. In an overhead cam motor, in the shape of a roller, the cam follower is built into the rocker arm.


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