This fuel filter removes particulate and water from the diesel supply before the fuel reaches the injection pump. It is installed in the fuel line between the tank and the high-pressure side of the system. A restricted filter reduces fuel flow, causing power loss and hard starting, while a fully clogged element can starve the injection pump and lead to cavitation damage. The filter uses a threaded mounting interface that matches the original housing for a secure seal. Replace the sealing washers on reinstallation and prime the system after fitting.