AG Mechanics CDE Practice Exam 2025 - Free AG Mechanics Practice Questions and Study Guide

When checking the valve clearance on OHV (Overhead Valve) engines, the clearance is checked between the valve stem and the camshaft. The camshaft is responsible for opening and closing the valves at the correct time in the engine's cycle. By checking the clearance between the valve stem and the camshaft, mechanics can ensure that the valve is opening and closing properly, allowing for optimal engine performance.

The other options are not correct:

- The clearance is not checked between the valve stem and the cylinder head because the cylinder head is the component that houses the valves and does not directly interact with the valve clearance measurement process.

- The pushrod is a component that transfers motion from the camshaft to the rocker arm to actuate the valves, but the valve clearance is not checked between the valve stem and the pushrod.

- The rocker arm is responsible for transmitting the motion from the pushrod to the valve, but the valve clearance is not checked between the valve stem and the rocker arm.