Engine fuel supply system

摘要

A fuel supply system for providing fuel from a fuel source to a combustion chamber of an engine is disclosed. The fuel supply system includes a vapor separator in which vapor is separated from fuel supplied from the fuel source. A pre-pressurizing pump pressurizes fuel from the vapor separator to a first pressure and delivers it to a high pressure pump. The high pressure pump pressurizes the fuel to a pressure above the first pressure and delivers it to a fuel rail to which is connected a fuel injector for delivering fuel into the combustion chamber. A fuel return line extends from the fuel rail for returning undelivered fuel back to the fuel system. A valve controls the flow of fuel through the return line and maintains the fuel at high pressure in the fuel rail. A fuel cooler is provided along the return fuel line.