Water or Emulsified Water/Fuel in Filter Can

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
Replaced fuel filter as I have done many times. After I get filter out I look and expect to see clear fuel. It was cloudy. Never seen this before. I sucked the fuel out, installed new filter, ran pump with VCDS, started right up up. Replaced filter 5 or 6 times over many years and miles. Every time fuel was clear. Not this time.

Anyone ever see this? I assume this is water. Should I be worried. Should I drain or sample tank? Shoukd I pull top off filter housing and re-check?

I get my fuel at Murphy (Walmart). They do a lot of diesel sales.
 

ZippyNH

Veteran Member
Joined
Apr 22, 2015
Location
Southern NH
TDI
2015 JETTA TDI SE
Sounds like the filter did its job
Truckers often have a Valve on the bottom of a clear filter holder and drain it weekly to remove water and visually check the filter. Reality is you can have a filter last 1000 miles or 100,000 on sheer luck....
Diesel does hold moisture based on temps, so with a big Temp swing, water can settle out even from a good supplier
It's simply the nature of the beast. Same for waxes, etc that are found on filters in the winter...more often before ulsd
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
In
Sounds like the filter did its job
Truckers often have a Valve on the bottom of a clear filter holder and drain it weekly to remove water and visually check the filter. Reality is you can have a filter last 1000 miles or 100,000 on sheer luck....
Diesel does hold moisture based on temps, so with a big Temp swing, water can settle out even from a good supplier
It's simply the nature of the beast. Same for waxes, etc that are found on filters in the winter...more often before ulsd
Thanks for reply. To satisfy my curiosity. I'm going to try and sample fuel from tank, may and may open filter can up again, take a look see. May be I won't. Ha ha. 😀

In my research some water 20ppm in diesel is beneficial. Un fortunately I extracted the fuel out with my oil extraction machine. I would have liked to have seen if water settled and gauge water volume for neird science fun. Guess I have been lucky with little to no water in fuel up to now.
 

ZippyNH

Veteran Member
Joined
Apr 22, 2015
Location
Southern NH
TDI
2015 JETTA TDI SE
Additives can sometimes help...Power Service-winter version, the white bottle, has an emulsifier in it to prevent slugs of water from going thru your fuel system, possibly causing damage due to lack of lube (I would assume bigger temperature swings and less ability to hold moisture in cold temps can cause more risks of this vs summer when it typically just slowly gets passed thru as "dry" fuel absorbs a bit of moisture).
Generally if the filter doesn't have a dark black scum on it, just dirty looking, you are usually fine. Fuel systems that have moisture in them can get algae and bacteria growth issues too....there are chemicals for that that typically will kill it and remove it, causing you to need to change filter SEVERAL times for the first couple tanks of fuel. Typically it's only used if a problem is severe and causing issues.
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
Additives can sometimes help...Power Service-winter version, the white bottle, has an emulsifier in it to prevent slugs of water from going thru your fuel system, possibly causing damage due to lack of lube (I would assume bigger temperature swings and less ability to hold moisture in cold temps can cause more risks of this vs summer when it typically just slowly gets passed thru as "dry" fuel absorbs a bit of moisture).
Generally if the filter doesn't have a dark black scum on it, just dirty looking, you are usually fine. Fuel systems that have moisture in them can get algae and bacteria growth issues too....there are chemicals for that that typically will kill it and remove it, causing you to need to change filter SEVERAL times for the first couple tanks of fuel. Typically it's only used if a problem is severe and causing issues.
Yep, having serviced my car myself for the last 13 yrs the fuel filter and fuel in the can, has always has been squeaky clean. This time filter looked new after 20K miles as always. However the fuel in the can shocked me being cloudy. As I said I extracted the fuel. Normally I leave the fuel in when it's clean. Put it together. It is running fine.

There was no big ambient temp swinging, just a light cooling (from 90's to high 80's). That is a great relief from the blow torch temps we had the last few months. Fall can't come quicker.

My plan is run a tank of gas though it, refill, drive a bit, and take the fuel filter out and take a look again. It should be OK. This area in Tennessee does not get that cold, only a week or two below freezing typically, snow is rare, single digit temps every 10 yrs. I clearly got water in the tank. Thanks for reply.
 
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oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
We have about 600 hours on our Bobcat T66, and have never noticed anything but clean red diesel in the bottom of the water separator. After refilling the fuel tank, via the same method for all the other times, and from the same source as all the other times, and the same source for all the rest of the equipment, about 20 minutes in... the "derate: water in fuel" warning came out. Got out and checked, the bottom of the separator was nothing but clear-cloudy water. Drained it out (about a cup) until fuel came out. Reset the alarm, never did it again.

Sometimes.... ya just get a bad batch. In this case, the sensor did its job.
 

lemoncurd

Veteran Member
Joined
May 24, 2019
Location
Eastern CT
TDI
2013 CJAA GTB2266
Can you be more cryptic? Your point. What should I do?

The car is running fine. I drained (extracted fuel/water mix out) and replaced filter. What is the problem?
more playing on the specific words you used. "gas"
running a tank of gas through your TDI would be catastrophic.
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
more playing on the specific words you used. "gas"
running a tank of gas through your TDI would be catastrophic.
OH OH Yes GOOD catch.... Ha ha.... Yes I was so paranoid about that when I first went to compression ignition propulsion. After 14 yrs of diesel I may be getting complacent, not only in words but less vigilance at the fuel depot. Of course I look for green handle, fill. I still get receipt and look to see it says diesel.

I saved my fuel receipts from the start, because Heidi (yes name my TDI) was under warranty (at one time). I had heard VW tried to blame owners (and may be rightfully so) that they put gasoline not diesel in the tank to deny warranty. So I kept records.

I am getting lazy about it now. I had all my receipts for all my fill ups since 2011!!! I tossed them out, except for recent fill ups. I still get and read receipt (to see it says diesel) and still keep for a period of time, log the price, gal, range, MPG in a logbook.... reset OD, trip computer. I just am not so OCD about it.

Fun fact or nerd fact.? Fuel receipts after a year or three, depending on where you keep them, does a disappearing ink trick. I ran into that with a battery 5 yr warranty. The thermal printed receipt was in kitchen drawer. Had receipt but it was almost unreadable after a few years when I needed to return battery. It is worse if you leave in car. For important receipts take a picture and email it to myself.

.I do have the blocker in the filler neck done by VW Mod along with the dumb stickers..... But you can not be too careful. Thanks for the reminder, gas is not diesel fuel... Never made that mistake yet and and never plan on it.... Butt words matter. Cheers.
 
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gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
Well curiosity killed the cat. After driving about 200 miles, tank near empty, filled up tank. I drove another 80 miles.

I pulled the new fuel filter I just installed 2 weeks ago. It was clean of course. FUEL? Yep looks good. I extracted it into a clean catch can with a handy-vac. It is now sitting in a glass jar with lid. It looks clean, yellow green, clear-ish. Is it crystal clear bright? It is not cloudy. See pictures. What do you think. After draining I wiped the can out and reinstalled the filter. I am going to let the drained fuel sit. I may put in frig or freezer and see what happens for fun.

In my original post I said fuel filter looked clean. I had it in a bag for a week open to air. When throwing it out I looked and it closely. It had some discoloration, I did not recall when I took it out. To be honest I did not inspect it carefully when first removed. Not sure if that is Microorganisms? Oxidized or something? Or it was discolored when I removed it and did not notice.

Pictures of fuel sample from fuel filter can.




Solution not to worry and change filter in 10K miles, vs 20K miles.
 
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