This tappet is a mechanical component in the fuel system of the host tractor. It transmits the camshaft lobe motion to the fuel injection pump plunger, controlling the timing and volume of fuel delivery to the engine. A worn tappet produces a loss of lift or altered timing, which results in rough running, reduced power, or hard starting. As an original AGCO part, the tappet is machined to the same face hardness and stem diameter as the original assembly, maintaining the correct valve clearance without requiring shimming. On reinstallation, check the tappet bore for wear and replace the gasket at the pump mounting flange.