[DirtyOil]

"points more towards water than air in the fuel. Basically blaming poor filter design along with higher pressure systems allowing water to get through the filter"


From the refineries (at least here in Canada) water content right from the producer may contain up to 200ppm water in the diesel. This amount will be suspended in the fuel and will not affect the injectors. The water/fuel separators on modern diesel engines is more then sufficient. Its the maintenance of these filters or lack of, I should say, is what causes issues. Water destroys injector tips primarily. There isn't a filter on earth that will completely remove the water from diesel fuel. If you read enough you will also note these FASS and AirDog pumps/filters have issues as will, IMHO they're not worth the money.

If your fuel tank gets a build up of "free water" at the bottom of the tank, then a good aftermarket water/fuel separator may be required and this filter should be drained each time you fill up. As a preventative maintenance measure, I will drain some fuel off the filter on my truck at every third fill up. I drain it into a old mason jar to check for water or debris.

In a nut shell the amount of "microscopic" water in the fuel is really nothing to worry about, its the amount of "free water" that should be of concern.