Understanding the Automotive Tappet: Types, Operations, and Maintenance

Automotive tappets, also known as cam followers, are important components of internal combustion engines. They are responsible for opening and closing the valves in the engine, which allows air and fuel to enter the combustion chamber and exhaust gases to exit. Tappets are small, cylindrical components that ride on the camshaft and are held in place by the engine's valve train.

In this article, we will take a closer look at automotive tappets, how they work, and their role in the engine.

Types of Tappets

There are several types of tappets used in internal combustion engines, including hydraulic, solid, roller, and mushroom tappets.

Hydraulic tappets use oil pressure to maintain contact between the tappet and the camshaft. This results in a quieter operation of the engine, as the tappet is always in contact with the camshaft, reducing any valve train noise. Solid tappets, on the other hand, are made of solid metal and do not use oil pressure to maintain contact with the camshaft. They are typically used in high-performance engines and require frequent adjustments to maintain proper valve lash.

Roller tappets use a roller bearing to reduce friction between the camshaft and the tappet, allowing for smoother operation and less wear on the components. Mushroom tappets have a large, flat surface area that contacts the camshaft, and are typically used in engines with flat tappet camshafts.

Tappet Operation

Automotive Tappets are responsible for transferring the motion of the camshaft to the engine's valves. As the camshaft rotates, the cam lobes come into contact with the tappets, causing them to move up and down. This motion is transferred to the pushrods, which in turn actuate the rocker arms. The rocker arms are responsible for opening and closing the engine's valves.

In hydraulic tappets, a small piston inside the tappet body is used to maintain contact with the camshaft. When the cam lobe comes into contact with the tappet, it compresses the hydraulic fluid, causing the piston to move upwards and maintain contact with the camshaft. This allows for quieter operation of the engine, as there is no clearance between the tappet and the camshaft.

Solid tappets, on the other hand, require a small amount of clearance between the tappet and the camshaft. This clearance is known as valve lash, and must be adjusted periodically to ensure proper operation of the engine.

Tappet Maintenance

Tappet maintenance varies depending on the type of tappet used in the engine. Hydraulic tappets typically require very little maintenance, as they are self-adjusting and do not require periodic adjustments. Solid tappets, on the other hand, require frequent adjustments to maintain proper valve lash.

Tappet wear can also be an issue in high-performance engines, where the increased forces and stresses can cause accelerated wear of the tappet and camshaft. This can result in increased valve train noise, reduced engine performance, and even engine failure if not addressed.

Conclusion

Automotive tappets are an important component of internal combustion engines, responsible for transferring the motion of the camshaft to the engine's valves. They come in several different types, including hydraulic, solid, roller, and mushroom tappets. Proper maintenance and adjustment of tappets is important for ensuring proper engine operation and preventing premature wear and failure of the components.

Read More: https://techninja99.blogspot.com/2023/02/hydraulic-vs-mechanical-tappets-which.html