Diesel fuel system diagrams start with the diesel tank, which holds the vehicle's fuel. The fuel first travels through a low pressure pump, which sends it through a filter that sifts it for any impurities that may harm the engine. It then hits the fuel injection pump, which applies the appropriate amount of pressure to the fuel. The pump uses fuel injectors to systematically inject the cylinder with fuel after each engine cycle's compression stroke.
A properly working diesel fuel system delivers fuel precisely and above atmospheric pressure. The system atomizes the fuel, and any excess fuel from the injection pump returns to the filter.
Improperly working diesel fuel systems often require very simple fixes. An engine that is emitting less power than usual could have dirty fuel filters or a build-up of lubricating oil that has oxidized. Both of these problems are fixed by changing the item in question.
Diesel fuel systems differ from gas fuel systems in both parts and timing. Diesel systems are air tight and the supply of fuel is determined by the compression stroke, but gas systems are cued by the suction stroke to pump fuel through the carburettor and into the engine. Diesel systems hold several advantages over gas systems, including a higher fuel economy, a longer working life, and minimal carbon monoxide emissions.