So the other day I decided to change both my fuel filters. (Baldwin PF7977 and CAT 1R-0750). I changed the Baldwin and it looked dirty but not too bad. I then proceeded to change my CAT filter and decided to dump the fuel that was inside the CAT filter into a clear jar for some unknown reason, I had a "hunch" I guess. To my suprise I saw little black ***** of what appeared to be filthy algae ridden water of some sorts floating in the jar. I have two concerns here. Number one, what the heck is it exactly (sorry no pics) and shouldn't the Baldwin have stopped this crap from going into my fuel system? Although I am thankful the CAT stopped it. Looks like I need to add a water seperator further upstream if this was in fact what it was. I cant imagine anything else besides water would make perfect little spheres floating in the jar. Additionally the CAT 1R-0750 is not a water seperator but I guess it will do it to some extent? Let this be a wake up call for those of you who dont have any additional fuel filtering besides the factory set-up, even if you do use the better Baldwin PF7977... Oh and all fuel is purchased at Love's truck stop so I know I have a better chance and getting cleaner fuel.

 

Water won't float in fuel, it's heavier (by roughly 2lbs per gallon).

No idea on what you saw, but its good the filter stopped it.

 

I guess to clarify a bit better the "spheres" were slowly going toward the bottom. Just the turbulence of the fuel as I was dumping the contents from the filter into the jar made them sort of float around but not end up on the surface.

 

Water can be found in your fuel as you described in tiny droplets. It will seperate to a point but diesel will absorb water and retain it, this is the reason why using a proper water seperator along with NOT using addtives with emulsifyers is very important.
If your seeing lots of these droplets then you need to drop your fuel tank and clean it real well. Fuel water seperators are only designed to seperate so much water then they stop working. I suspect the Baldwin reached its water seperation point andallowed water to get through.

Good catch and get that system cleaned up.

 

Still not convinced that's water, I have never seen water come off the bottom of the jar in drop form.