Image Number 9 for United States Patent #6877306.
A fuel system having an ecology valve controlling liquid flow through a retention passage when pressurized liquid is passed through the valve is presented. The retention passage winds between the valve outlet and a cavity such that no matter which way the valve is oriented gravity alone is unable to drain liquid from the cavity to the outlet. The ecology valve serves to suction fuel from fuel nozzle passages upon engine shutdown. Fuel is temporarily stored in the cavity and the retention passage. The ecology valve also provides a fuel splitting function for providing a port geometry determined split between fuel nozzles in the fuel system.