Rocker Arm Function: Components & How It Works

Talking about the air circulation system of the engine and engine combustion certainly cannot be separated from the valve mechanism system. Within the valve mechanism system itself, there is a component called the rocker arm. Curious about what a rocker arm is, its function, components, and how it works? Let's dive into the discussion below.

Function of the Rocker Arm

When you hear the name rocker arm, you might feel unfamiliar and have just heard it.

You're not alone in feeling this way; most car drivers also do not know what a rocker arm is. Another name for the rocker arm is often referred to as a tappet or valve lifter.

Many might also be wondering, where is the rocker arm located? You can easily find this component in cars that have an overhead camshaft (OHC) and overhead valve (OHV) engine.

Here are some functions of the rocker arm:

1. As an Intake Valve

The main function of the rocker arm is to act as an intake valve (opening and closing the intake valve) whose movement is influenced by the camshaft lobe (cam lobe) as the driver of the rocker arm, thus creating air circulation and combustion within the engine.

2. As an Exhaust Valve

The rocker arm functions as an exhaust valve or is known for the opening and closing process of the exhaust valve so that the combustion residue in the combustion chamber goes directly to the exhaust manifold area.

3. Connecting the Camshaft with the Valve

The third function of this component is to connect the camshaft with the valve.

The rocker arm works using friction caused by the camshaft and the valve, stabilizing the air circulation in the engine. This will certainly affect the car engine's performance to be lighter.

4. Assisting the Combustion and Air Disposal Process in the Engine

For the engine to run well, it certainly requires a combustion process. The engine combustion process occurs due to the presence of fuel and engine drive components, resulting in combustion products.

To ensure this process runs smoothly, circulation in the exhaust or intake valve area is necessary.

Rocker Arm Components and How They Work

As previously explained, the rocker arm has a function as a connector to other components such as valves and camshafts. Cylinder head components play a significant role in the cooling process of your car.

There are several rocker arm components that you should know along with how they work as follows:

1. Valve

A valve is a component that functions as the main door for the entry and exit of air or fuel and exhaust gas during the combustion process.

The valve used for the entry and exit of fuel is called the intake valve, while the one for the exit of exhaust gas is called the exhaust valve.

2. Camshaft

This component functions as the opener and closer of the valve at its timing. The operation of the camshaft is divided into two.

The first operation occurs when the camshaft is in a pressing position. The pressing process starts from the cam lobe shaft and contacts the rocker arm until it hits the valve, causing the valve to open.

The second operation occurs when the position is not pressing. In this condition, the cam lobe shaft stops pressing the rocker arm and valve, causing the valve to close.

3. Push Rod

The push rod is a component that functions as a conduit for the movement from the valve lifter to the rocker arm, creating an up-and-down motion. The use of the push rod is only for overhead valve type valve mechanisms.

The vital function of the rocker arm in engine performance makes it necessary for you to maintain the condition of this component.

Regular checks should be conducted; if this component is damaged, immediately replace it with a new one by purchasing it at an official workshop or the nearest Daihatsu dealer.

Tips Sahabat