The attached is another idea that I found to be essential for any boat intending to go cruising. Outside the U.S and even in the U.S. the fuel can be dirty. This fuel can have water and sediment that will quickly clog the filters. This system cleans the fuel of most of the water and sediment before it reaches the fuel filters. You will find that you will rarely have to change your filters if you use this system.
I realize that this is covered in my book but this attachment explains how to build and install the system.
Since I posted this, there seems to be some confusion about the gate valve in the center of the photo. That gate valve has nothing to do with the system. The gate valve came with the fuel sight glass you see in the photo. If the sight glass has to be replaced or breaks, the valve can be closed to prevent losing the fuel. Sorry, about that confusion…
Roger
http://www.samlmorse.com/nereus/Installation_of_RCI_fuel_filter.pdf