The fuel tank stores fuel in a convenient location, away from the engine. It is commonly made of steel or aluminum. Baffles ensure the pickup tube is always submerged in fuel. This stops air entering the system. The inside of the tank can be treated to prevent rust. Galvanizing must never be used, because diesel fuel, reacts with zinc to produce powdery flakes that can block fuel filters.
A diesel fuel tank should be kept full, to prevent water condensing on tank surfaces and contaminating the fuel.
In light commercial diesel engines, two fuel lines are used. One carries fuel from the tank to the filters, and then to the fuel injection pump. The other is the return line. It carries back to the tank the fuel that is used for lubricating and cooling the injectors, the injector pump, and for bleeding the filters.
They are usually made of seamless steel tubing, coated with tin to prevent rust. Sometimes cadmium is used instead of tin.A fuel line must be large enough to provide enough fuel flow for maximum power.
It’s supported under the vehicle by nylon insulators in brackets. Reinforced synthetic rubber hoses allow for movement, and vibration of components. The reinforcement is needed because the fuel line is subject to variations in pressure.
Injector lines are made of cold-drawn, annealed, seamless steel tubing. The bore of the pipe is kept to the smallest diameter possible, and all of the pipes are the same length. If pipes of different lengths were used, it would affect injection timing.
