This valve tappet transmits motion from the camshaft lobe to the pushrod that actuates the engine valve. It sits between the camshaft and the valve train, converting rotary cam motion into linear movement. A worn tappet produces a ticking noise from the valve cover and can alter valve timing, reducing engine power. This component is manufactured to the original geometry so that the contact face matches the cam lobe profile and the pushrod seat aligns with the rocker arm. On installation, verify the tappet rotates freely in its bore and apply assembly lube to the cam-contact face before initial start-up.