Fuel Lines and Hoses

     Fuel lines and hoses carry fuel from the tank to the engine. The main fuel line allows the fuel pump to draw fuel out of the tank. The fuel is pulled through this line to the pump and is then forced into the metering section of the fuel system. Fig. 4. 2 shows a complete set of fuel lines, including the fuel vapor lines for the evaporative emissions control system.

    Fuel lines are normally made of strong, double-wall steel tubing. For fire safety reasons，a fuel line must be able to withstand the constant and severe vibration producedby the engine and road surface.

    A fuel rail is a large-diameter fuel line that feeds fuel into multiport gasoline injectors.It serves the same purpose as the fuel line but provides a greater volume of fuel right before the injectors. The fuel rail prevents any injector from starving for fuel under high-demand conditions.

    Fuel hoses，made of synthetic rubber, are needed where severe movement occurs between parts. For example, a fuel hose is used between the main fuel line and the engine.The engine is mounted on rubber motor mounts. The soft mounts allow the engine some movement in the car frame. A flexible hose can absorb this movement without breaking.Hose clamps secure fuel hoses to the fuel lines or metal fittings.