dieseldorf,
You have been very lucky in your fuel purchases.
You have no idea as to the water content that is going into your fuel tank. Past experience is no indication of present or future water content of the fuel you buy.
Your TDI would run like a gasser with a loose spark plug wire if whole water were being sent out to the injectors. Water has much lower energy content than fuel.
Does it run like that? If not, you have not had whole water problems. If whole water gets sent out to the injectors, the filter/sep was overwhelmed and whole water was sent en mass to the pump ...... Not possible, or better yet, not feasible, to prepare for this and continue to run. This happens after re-fueling and taking on enormous amounts of water. Can't be prevented.
And you need to understand that prior to the high pressure injection stage, the fuel must have been through the feedpump. The feed pump will whip any water/fuel into a localized emulsion.... It would be highly unlikely that whole water will ever make it through the feedpump and to the high pressure stage as whole water!!! ..... unless there was gross water contamination... that engine ain't gonna run again until it is drained and purged. That ain't the objective of a fuel sep or additives.
Notice that the fuel passes through the filter separator before it passes through the feedpump...... for a good reason. Suction side water sep is much better.
Also, be aware of the differences in free (whole) water and suspended (dissolved and/or emulsified) water.
If a separator can stop large amounts of water, it can stop the small amounts. Whole water that is. It isn't like a window screen that can stop the really big bugs but passes the little ones. The greater volumes of water a separator is subjected to, the greater the amount of water that will pass. Again, whole water. Separators have ratings in percent of water exposed, such as 98% of the water will be separated.
But in order to understand that, you must understand the two forms of water: whole & suspended. Whole is free water. Settles to the botttom.
Suspended is dissolved or emulsified. Ain't much that can be done in the car about dissolved. Forget it. Emulsified can be precipitated, with the help of a demulsifier.
Also, the water particles can be larger than the filter rating which will help remove even more water. ie: a 2µ filter media.
So let's say that you have some water in your filter/sep. The emusifier you added will help to dissolve that water and send it through your fuel system. Are you sure you want to do that? I really don't want to help whole water go into solution and then through my pump and injectors. Why do you see this as an advantage?
I would rather have water puddle on the bottom of my tank and have an occasional slug pulled up and deposited in the fuel separator, which handles free water, than dissolving all free water that may form in the system and run it though the pump and injectors. But hey, that's me.
I see it as better to try to take as much water out of suspension and put it in the separator, which will minimize the water that the pump and injectors are subjected to. The water, in any amount will still cause corrosion, a leading cause of fuel systems failure. The less water, the less corrosion. This is also what the diesel industry does as standard operating procedure. Even I am not going to argue with that.
