What are the two types of lifters found in engines?

The two types of lifters found in engines are hydraulic and mechanical. Hydraulic lifters use engine oil to maintain a constant pre-load on the valve train, allowing for automatic adjustment to variations in clearance between the lifter and the pushrod, which helps in minimizing noise and providing smoother operation. This self-adjusting characteristic is beneficial in maintaining proper valve timing and reducing maintenance needs.

On the other hand, mechanical lifters, also known as solid lifters, require manual adjustment of clearance, meaning they do not use oil pressure for adjustment. This type of lifter can provide a more direct valve movement and can be beneficial for high-performance applications, allowing precise control over valve timing.

Understanding these two lifter types is crucial because they directly affect engine performance, maintenance, and the overall efficiency of the engine’s operation.