In the valve train, which part couples motion from the cam follower to the rocker arm?

• A. Pushrod
• B. Poppet valve
• C. Valve guide
• D. Valve spring

Answer: (A)

Motion in a traditional valve train is transferred from the cam follower to the rocker arm through a pushrod. The cam lobe pushes the lifter (cam follower), which then relies on the pushrod to convey that vertical motion up to the rocker arm. The pushrod acts as the link that allows the rocker arm to pivot and lift the valve stem to open the valve. The other parts have different roles: the poppet valve is the component being opened, the valve guide keeps the valve aligned, and the valve spring returns the valve to its seat and keeps it closed when not opened.