AG Mechanics CDE Practice Exam

Where are the valves installed in an overhead valve arrangement?

1. In the crankcase

2. In the cylinder block

3. In the cylinder head

4. Near the piston

The correct answer is: In the crankcase

The correct answer is that in an overhead valve arrangement, the valves are installed in the cylinder head. This setup allows for a more efficient engine design as the valves can open and close more directly in relation to the combustion chamber where the fuel-air mixture ignites. In this arrangement, having the valves positioned in the cylinder head contributes to better airflow, which enhances engine performance and efficiency. It also means that the pushrods and rocker arms, which may be utilized to open and close the valves, are more effectively aligned with the piston's movement, optimizing the timing of the valve operation. The other options do not fit the characteristics of an overhead valve arrangement. Valves are not located in the crankcase, the cylinder block, or near the piston in this design, as that would contradict the fundamental engineering principles of an overhead valve arrangement. Instead, the design focuses on maximizing the efficiency of the combustion process through proper placement in the cylinder head.