The tensioner's function is to guide and tension the timing belt or timing chain in the engine, keeping it in the optimal tension state at all times. It generally comes in two types: hydraulic and mechanical, both of which can automatically adjust the tension of the timing belt and timing chain. Overview: Driven by the timing belt or timing chain, the camshaft opens and closes the valves at the correct time, coordinating with the piston to complete the four processes of intake, compression, power, and exhaust. Since timing belts and chains can experience jumping during medium to high-speed operation, and timing belts can stretch, deform, and develop misalignment over time due to material wear and stress, this can lead to inaccurate valve timing. This inaccuracy can cause issues such as increased fuel consumption, loss of power, and engine knocking. Excessive misalignment can also cause the valves to open too early or close too late, leading to collisions between the valves and the upward-moving piston, which can damage the engine. Additional Information: To maintain the proper tension in the timing belt or chain—neither too loose to cause misalignment nor too tight to cause damage—a specialized tensioning system is used, consisting of a tensioner and a tension pulley or guide rail. The tensioner provides pressure directed at the belt or chain, the tension pulley makes direct contact with the timing belt, and the guide rail directly contacts the timing chain. As they move with the belt or chain, they apply the pressure from the tensioner to maintain the appropriate level of tension.
