This fuel supply pump mounts to the engine block and delivers fuel from the tank to the injection system. It is a mechanically driven pump that maintains a steady flow and pressure to the high-pressure injection pump. A worn or failing pump causes hard starting, loss of power, or erratic engine operation. The pump includes a sealing gasket that must be replaced on reinstallation to prevent air ingress into the fuel system. As an original-manufacturer component, the pump body and mounting flange are machined to match the engine block interface without requiring shimming or adapter plates.