Question: does a diesel engine have a fuel pump

Answer: Yes, Diesel fuel pumps operate at a much higher pressure due to the engine's specs and are usually mechanical pumps such as common rail radial piston pump, common rail two piston radial, inline pump, port and helix, and metering unit design. Radial piston pumps used in cars and trucks are fuel lubricated, this helps with keeping oil out of the high pressure fuel. Oil in the fuel can raise emissions and clog injectors. Many diesel engines are common rail, which means all the injectors are supplied by one pipe full of high pressure fuel supplied by the fuel pump. Common rails dampen the pressure fluctuations when fuel is used by each injector and pumped into the cylinder. Common rails also make it easier for the fuel pressure to be measured by one device instead of one per cylinder. Port and Helix (plunger type) high pressure fuel pumps are most commonly used in marine diesels because of their simplicity, reliability, and its ability to be scaled up in proportion to the engine size.