BMW X5 Diesel Water Separator?

[youry]

Originally Posted by Doug Huffman

Sorry, I did not know that American English is not your preferred language.

Immiscible means UN-MIXABLE
https://en.wiktionary.org/wiki/immiscible

Out of habit, my bad.

[Doug Huffman]

Originally Posted by youry

... one pint of water which is mixed with 20 gallons of fuel. That's something like 2% water 98% fuel...

By volume: 1 pint in 160 pints (8 pints/gallon x 20 gallons) is 0.00625 or 0.625%. Not even 1%

[windforce]

Thanks for all the concerns, my friends! The engine runs fine. No CEL yet. Should i add some Redline water remover/injector cleaner? And do a engine oil change?

[regdfry]

For peace of mind add a water remover, like PS Clear-Diesel: here is info from their website.


Clear-Diesel Fuel & Tank Cleaner is an advanced diesel fuel and tank cleaning technology. Water has always been a problem in diesel fuel. But today’s cleaner-burning fuels have dramatically reduced sulfur content and are more prone to water separation, contamination and are inherently unstable. This Fuel Polishing Formula removes water and slime, disperses fuel contaminants and stabilizes fuel during long-term storage. It can be used as a vital part of any preventive maintenance program or for immediate clean-up of equipment or fuel storage tanks. Add Clear-Diesel at least quarterly or as needed.
Benefits

Disperses diesel fuel contaminants
Removes water and slime
+Petrofresh provides maximum long-term storage stability – keeps fuel fresh
Prevents premature fuel-filter plugging
Protects against fuel tank corrosion
Effective in conjunction with Bio Kleen Diesel Fuel Biocide to remove residual water and contaminants during microbial contamination clean-ups
Effective in all diesel fuels, including Ultra Low Sulfur Diesel (ULSD), biodiesel and biodiesel blends
Does not contain alcohol of any kind
Safe for use in all diesel engines
Will not void engine manufacturer's warranty when used as directed

[ZetaTre]

The water separator is built into the fuel filter element (it has a coalescence filter to increase the size of water droplets to a point that can be effectively stopped by a hydrophobic membrane) which is under the driver side seat, behind the plastic that has the two big holes (if you crawl under the car you'll see what I'm talking about).

Water will get filtered out and will not go past the filter. I'd actually be worried about using any additives that may cause the water to go passed the filter to the HPFP or the injectors.

Like Mr Huffman said the two don't mix which is good thing (because the filter can stop it effectively) and you don't want to add something that mixes the two.

If the filter gets too much water and clogs you'll get a code, but I believe that it may not trigger the CEL.

You may want to think about changing the fuel filter.

[Doug Huffman]

Originally Posted by ZetaTre

The water separator is built into the fuel filter element (it has a coalescence filter to increase the size of water droplets to a point that can be effectively stopped by a hydrophobic membrane) [ ... ]

LOL Gore-Tex®??

[ZetaTre]

Originally Posted by Doug Huffman

LOL Gore-Tex®??

Polytetrafluoroethylene is used in water separator membranes used in diesel filters... So, yes, could be Gore-Tex®

[windforce]

I bought a bottle of this.

Amazon.com: Red Line 60302 Fuel System Water Remover & Anti-Freeze - 12 Ounce: Automotive

Would you guys recommend me to use it?

[regdfry]

Originally Posted by windforce

I bought a bottle of this.

Amazon.com: Red Line 60302 Fuel System Water Remover & Anti-Freeze - 12 Ounce: Automotive

Would you guys recommend me to use it?

I would NOT use a product that is designed to work in both gasoline and diesel. However, their web site, redlineoil.com says it can be used in conjunction with a couple of their diesel additives. Did also note the product you have, treats 250 gallons (or 21 tanks on your X5).

I would use the Power Service Clear-Diesel, since that company specializes in Diesel products. I would treat your current tank. . . run it to near empty; then, treat the next fill too!

I don't have a clue how much water got into the tank. . . Good Luck. Let us know what you decide / do.

[ZetaTre]

I would not use a product that allows water to go through the high pressure fuel system... Regardless of the name, brand or chemistry of whatever snake oil it is.

Diesel is very fortunate in the fact that it does not mix with water which can be easily separated out mechanically through filtration (diesel also have specific gravity of <1 so water will drop at the bottom of the tank where the fuel pickup is; no need to run the tank dry). Gasoline blended with ethanol are not so fortunate and Bosch has gone on the record by blaming the fact that ethanol is hygroscopic to failures in the direct injection high pressure fuel system.

You want to keep water out of there and you have a water separator that does just that. If in fact you have water in your tank you do not want it to go past the HPFP.

So if you're asking for my opinion, I would not use any of such additives (and that is assuming they do what they claim) but I would simply replace the fuel filter perhaps in close sequence, if, again, you're worried.