Valve lash is defined by the gap between which components?

• A. Pushrod and Cam Lobe
• B. Bucket and Valve Stem
• C. Rocker Arm and Valve Tip
• D. Cam Lobe and Valve Tip

Answer: (C)

Valve lash is the small clearance in the valve train where motion is transmitted to open the valve. In a typical rocker-arm design, that gap sits between the rocker arm and the end of the valve stem (the valve tip) where the rocker presses to lift the valve. This clearance ensures no binding when the valve is closed and accommodates thermal expansion, lubrication, and manufacturing tolerances.

If the gap is too small, the parts can preload against each other as the engine heats, causing interference, improper valve seating, and potential damage. If the gap is too large, the valve may not open and close promptly, leading to poor sealing, reduced performance, and more valve train noise.

Other interfaces in the train (like pushrod with cam lobe, bucket with valve stem, or cam lobe with valve tip) do not define the lash in this configuration; the measurable, adjustable clearance is specifically between the rocker arm and the valve tip.