Automotive
Fuel Delivery Systems

A typical fuel delivery system includes:

• fuel tank

•  fuel pump

• fuel filter

• fuel lines

• fuel pressure regulator

• fuel injector's

• The Fuel Tank

• • Fuel tanks are made of corrosion-resistant steel, aluminum, or molded polyethylene plastic.
  • Fuel tanks have baffles in them to prevent fuel from splashing around inside the tank.
  • • The baffles keep the fuel pickup and sending unit for the fuel gauge submerged in the fuel during acceleration and hard braking.
    • The baffles have holes or slots in them to permit the fuel to move from one end of the tank to he other.
  • Fuel tank is almost always located in the rear of the vehicle though there are some exceptions.
  • Fuel tank have a cap and inlet filler tube.
  • • Filler tube caps are not vented but may have a pressure-vacuum relief valve. Though normally closed, when extreme pressure or vacuum is present, the relief valve opens.
    • Fuel tank filler cap on today's cars are threaded into the upper end of the filler pipe. They require several turns counter-clockwise to remove.
    • • The long threaded area of the cap is there to allow any remaining fuel tank pressure to escape during cap removal.
      • When you tightening the cap on installation, you will hear a clicking noise. This noise tells you the cap is properly tightened and full seated.

• The Fuel Pump

• • The fuel pump is located in late model car in the fuel tank along with a strainer and float.
  • • The strainer is attached to the bottom of the pump and is there to stop dirt and residue that might be in the tank from entering the pump.
    • The float is attached to a sliding contact which operates the fuel gauge. As the float moves up or down the contacts position changes, varying the signal that the fuel gage receives.

• The Fuel Lines

• • The fuel lines carry the fuel from the tank to the fuel filter and fuel injection assembly. 
  • • Fuel lines can be made of either metal tubing, flexible nylon or synthetic rubber hose.
    • The flexible nylon or synthetic rubber hose must be able to resist gasoline. 
    • Hoses must also be nonpermeable, so gases and gas vapors cannot evaporate through the hose.

• The Fuel Filter

• • The fuel filter is located in the fuel line.  This is a large, heavy duty filter to filter out small particles of dirt while still allowing the pump to supply a substantial amount of fuel to the engine.

• The Fuel Pressure Regulator

• • A pressure regulator controls fuel pressure within the system so that an exact , predetermined amount of fuel will be will be delivered to the engine.

• The Fuel Injector's

• • Fuel injector are electromagnetic devices the meters and atomize fuel so it can be sprayed in the intake manifold of the car.