I ask this question elsewhere but would like to run it by you. If you are familiar with the Cat Fuel/water separator filter, please explain how they work. I understand how they settle out the water what I want to know is how fuel circulates through them. I have a filter in my hands as I speak. It is for a D3G 2005. There is a large opening in the top and a small valve in the bottom for draining the water. What I don't understand is how the fuel can come in the top and go out the top. I am curious if you know how that works.
Well there are two different ways those filters work.
One uses a filter design on the principle that water particles (for arguement sake you could say molecules) and fuel particles are a different size (water being larger). They simply make a filter that is slightly smaller than a water molecule and tadaa! The water is trapped on one side and the fuel is allowed to pass through.
The second uses a vortex, aka centrifugal power. Water is heavier than fuel so when the water/fuel mixture is pumped through the turbine the water is forced down while the fuel remains on top and is syphoned off by your downstream fuel line.
I believe they have models have both methods intergrated into one (filter first which also blocks out unwanted debris) and then the cetrifuge to spin out any smaller water particles that the filter missed.
Cool huh?