Water fuel separator

piper109

Veteran Member
Joined
Dec 6, 2003
Location
Ashe Co NC
There have been water separators in filters of past tdi models but the Common Rail models do not have them. This has fueled concern (yes pun intended) that there is inadequate protection for the delicate HPFP systems in these late models, one of which I see you have.
There is anxiety over the quality of the US diesel fuel supply and its worth the effort to be discriminating in this regard.

Steve
 

MayorDJQ

Top Post Dawg
Joined
Dec 4, 2001
Location
Williamstown, Mass
TDI
'10 Golf 2dr 6m, sold.
There have been water separators in filters of past tdi models but the Common Rail models do not have them. This has fueled concern (yes pun intended) that there is inadequate protection for the delicate HPFP systems in these late models, one of which I see you have.
There is anxiety over the quality of the US diesel fuel supply and its worth the effort to be discriminating in this regard.

Steve
That is not entirely accurate. There was NOTHING special about the fuel filter/water separators on earlier generation TDIs. Water simply collects at the bottom of the filter and can be drained through the petcock. Many people have incorrectly assumed over the years that because several ounces of liquid came out, that they drained several ounces of water. In some extreme cases this may have been true, but opening that petcock allows the entire contents of the filter to drain--water and fuel. I put ~200k on my two ALHs and never found more than a droplet of water when draining/changing their fuel filters. I had similar results with my '80 300SD, Audi 5000 Diesel, and several Diesel Rabbits.

That said, the CR fuel filter/filter DOES act as a water separator, just like in the previous TDIs. Liquid water will collect at the bottom of the canister, there's just no drain built into the housing. Water in suspension at the molecular level may get through the filter, just like it does on all previous TDIs.
 

Jack Frost

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Location
Rural Manitoba
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2009 Clean Diesel
It begs the question: what is a water separater?

The fuel tank is a water seperater. So is the fuel filter housing. My tracter has a petcock at the bottom of the fuel tank and I drain a bit of liquid there once in a while, but I never know if it had any water in it. The fuel filter is made out of clear plastic but I never see any water in it, but given I drain the fuel tank periodically, there should not any.

I believe the water seperater for our TDIs is the fuel filter. It is doubtful, given the surface tension of water, that any water would get through the fuel filter medai. If we just worry about changing the fuel filter and remove any water that may have collected in the bottom of the housing, I think we should be fine.:)
 

piper109

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Joined
Dec 6, 2003
Location
Ashe Co NC
In as much that water being heavier, will naturally sink to the bottom of a fuel filter housing then it is probably true that most filters have water separators. The earlier ones were designed for periodic draining however and the poster seemed to be under the impression that perhaps the present ones are too.

I too have had diesels for many years and I have drained out small amounts of water from time to time. Just last month I drained my ALH filter and there was a 1/2 teaspoonful of water in it.

All industrial diesels that I have seen usually have two filters and recently have sensors which indicate on the ECM's that water is present in their primary filters and throw a check engine code or warning. It is surprising to me that VW does not do something similar given the heightened sensitivity of the equipment.
 

specsalot

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Florida
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Well I'm thinking of doing things a little differently.

My plan is to use a kidney circuit by adding two pipes going through the lid of the tank unit, one going close to the bottom of the tank and the other close to the top.

Steve
Steve - If you look at 2micron's pictures there appears to be a "spare" (unused) spud on top of the fuel sending unit cover. therefore you only need to add one additional penetration to the cover itself. I'm assuming you will want your kidney pump to circulate all fuel in the tank not just recirculate the changing contents of the sending unit? Dweisel has pointed out that you shouldn't open up the sending unit unless you've pulled your tank down (at least below 1/2) or you can wind up with a real mess.

2micron
- Not sure if you've had a chance to look in detail at the contents of your fuel sending unit. Dweisel sent me one that got busted up in shipment. There appears to be some kind of an eductor element in the bottom. Have you had a chance to figure out what that's for in the grand scheme. Thanks in advance.

I can see I'm gonna have to get off the dime and get more hands on with my own car pretty soon :D
 
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MayorDJQ

Top Post Dawg
Joined
Dec 4, 2001
Location
Williamstown, Mass
TDI
'10 Golf 2dr 6m, sold.
It begs the question: what is a water separater?

The fuel tank is a water seperater. So is the fuel filter housing. My tracter has a petcock at the bottom of the fuel tank and I drain a bit of liquid there once in a while, but I never know if it had any water in it. The fuel filter is made out of clear plastic but I never see any water in it, but given I drain the fuel tank periodically, there should not any.

I believe the water seperater for our TDIs is the fuel filter. It is doubtful, given the surface tension of water, that any water would get through the fuel filter medai. If we just worry about changing the fuel filter and remove any water that may have collected in the bottom of the housing, I think we should be fine.:)
That's exactly what it is. The Mk2 Diesels had a water trap under the body of the car, but it proved unreliable and problematic. Fuel swirling in the filter will always precipitate out water and other contaminants. That's why they filter from outside to in.

On the few occasions when I've found liquid water in my drained fuel, it looked like a little globule on the bottom of the jar. (Always drained into a clean, dry glass jar.) I can't speak to the physics of a fuel filter re: surface tension and water passing through the media.

On those few occasions, was there any risk of the small amount of water being ingested by the engine? I doubt it.


All industrial diesels that I have seen usually have two filters and recently have sensors which indicate on the ECM's that water is present in their primary filters and throw a check engine code or warning. It is surprising to me that VW does not do something similar given the heightened sensitivity of the equipment.
I would suspect that industrial Diesels have dual filters and sensors because the fuel source is probably not as reliable. Most commercial fuel stations have underground fuel tanks, so the temperature of the tank/fuel should stay pretty constant. Assuming there are no cracks or other ways for water to seep into the tank, there should be very little water accumulation.

Whereas, the tanks in the back of construction/excavation company pick up trucks will see greater temperature fluctuations, potentially causing more condensation in the tank. Add to that that these machines are often working in grimy conditions, there's probably more gunk hanging around in the fuel filler opening, the risk for contamination is greater. Plus, these machines are consuming larger quantities of fuel, so more fuel used means more chance for contamination.
 
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piper109

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Dec 6, 2003
Location
Ashe Co NC
These are good points and I had already come to the idea of using that spud myself. Yes there is some kind of eductor in there (per Dang144) so I would plan to go around the whole unit with the pick-up tube and allow the fuel to flow in the top, perhaps even teeing into the return line. The 1/2 gal/min max extra flow would probably not affect much. Ideally I would like the lift pump to pick up freshly filtered fuel.....probably a long shot.

I am still selecting a fuel filter with suitable WIF sensor circuitry. Once that is lined up I will dig into the tank myself.

Steve
 

MayorDJQ

Top Post Dawg
Joined
Dec 4, 2001
Location
Williamstown, Mass
TDI
'10 Golf 2dr 6m, sold.
These are good points and I had already come to the idea of using that spud myself. Yes there is some kind of eductor in there (per Dang144) so I would plan to go around the whole unit with the pick-up tube and allow the fuel to flow in the top, perhaps even teeing into the return line. The 1/2 gal/min max extra flow would probably not affect much. Ideally I would like the lift pump to pick up freshly filtered fuel.....probably a long shot.

I am still selecting a fuel filter with suitable WIF sensor circuitry. Once that is lined up I will dig into the tank myself.

Steve
That's the $64,000 question though. The Fuel Pressure Regulator controls the pressure in the rail, so how will more/less fuel flow affect it? Will increased demand on the Aux Pump be a problem?
 

piper109

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Joined
Dec 6, 2003
Location
Ashe Co NC
The excess fuel that bleeds off the fuel rail from the pressure regulator makes its way back to tank in a line which essentially has no resistance to flow and therefore has no pressure to speak of. It joins with the excess fuel from the HPFP supply line and the drain from the injectors. The return line should have no pressure though it goes through some kind of temperature regulator in the filter lid which may restrict it a little.

The aux pump simply feeds the HPFP with excessive flow at 62 psi. The HPFP will accept the fuel it needs depending on rpm at its inlet (seeing as it has a pressure head of 62 psi, it would be wrong to call it a suction line). The excess of this drains off back to the tank at no pressure also.

I am suggesting to tie into the last few inches of this pressure free return line with the trickle return from my kidney loop.
I see no way that it could affect the functioning of the lift pump, aux pump or HPFP.

Steve
 
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Jack Frost

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Location
Rural Manitoba
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2009 Clean Diesel
... I can't speak to the physics of a fuel filter re: surface tension and water passing through the media.
Surface tension is the attraction that water molecules have for each other in the liquid form. Because of the structure of the water molecule, it has one of the highest surface tenision properties of almost any liquid. The only liquid that I know that has more surface tension than water is mercury.

It is the surface tension that makes small water drops "bead" and why certain small animals can walk on top of its surface. It is surface tension that keeps water in the bottom of your fuel filter canister a "globule".

Because of surface tension, it is difficult to break a water bead or globule into smaller ones. The smaller the bead, the more difficult that is. When one gets a globule down to the size of a fraction of a millimeter (mist), then it is extremely difficult to divide them into smaller ones anymore. This is soley because the strength of the surface tension at those small scales exceeds everthing else.

So imagine a water bead or glob trying to get through a filter. The fuel flowing by through the filter would have to be strong enough to break those beads into smaller beads that are small enough to flow through. These would have to be only a few millions of an inch in diameter. As long as the beads are this small, that is not going to happen. They will either become trapped in the filter or will sink down to the bottom where they may coaleasce into a larger bead.

As long as the larger bead at the bottom of the filter housing does not become large enough to submerge or otherwise touch the bottom of the filter, the filter is performing the water separation function. That is what the drain valves are for - to remove large water globules before they touch the filter. Surface tension does not work effectively on large water globules and the fuel filter cannot keep them and fuel separated.
 

piper109

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Joined
Dec 6, 2003
Location
Ashe Co NC
Jack, that is very informative.

In reading the documentation of filter manufacturers and water separators etc., they state that the action of pumping the fuel with a water content creates an emulsion of fuel and water which renders the water separators ineffective and the water remains in the fuel. They say then that it is necessary to draw fuel through the filter by installing the filters/separators on the suction side of pumps, preventing the formation of an emulsion and enabling the water separators to do their work by the principles you have outlined. Presumably the pumps are doing the very thing that you explain is difficult to do.

Many older diesels do in fact have lift pumps in the injector pumps that draw fuel all the way from the tank instead of having pumps in the tank that feed the injection system. There are even modern Common Rail diesels with Bosch HPFP that do this, Cummins for one. Not so for VW however where the filter is between the lift pump and the aux pump. This is one of the reasons I want to use a kidney loop where fuel is drawn through the filter/separator on the suction side of the circulation pump.

Steve
 

Jack Frost

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Location
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2009 Clean Diesel
First of all, I wouldn't call myself an expert on water separaters, but I have studied enough chemistry and physics to know what properties water takes on at the macro and microscopic level. If fact, for the last week, I have been watching for the last month a jar of hydraulic oil containing emusified water on my shelf. It is fascinating watching the emusified water slowly coalesce and sinking out to the bottom leaving the clear oil at the top.

But where was I ... oh yes, I remember.:eek:

I don't have access to the documentation you refer to, but sometimes they are written by salesman and not by engineers or at least a technical writer. Here are my comments:

they state that the action of pumping the fuel with a water content creates an emulsion of fuel and water which renders the water separators ineffective and the water remains in the fuel.
Your comment dos not specify the form of the water content of the fuel that is being pumped. It could be dissolved, emulsified, or just two mixed liquids. However, if it is safe to say that most liquid water in fuel would certainly be emulsified to various degrees after going through a pump. Some of that emuslifed fuel would dissolve into the fuel.

In other words, fuel that contains liquid water, after being pumped, would enter the fuel cannister in all it forms including the dissolved form which no fuel filter can seperate. So the statement that water remains in the fuel is always correct. That is the salesman talking.:rolleyes:

What the statement does not say, is that the liquid water and the extremely large beads and globules would fall to the bottom of the fuel cannister and the emuslifed form of oil (the very tiny beads of water that make look white) would be trapped inside the filter media where they will either remain until dissolved, or the fuel filter is replaced. All the time of course some water will always get by in the dissolved form which is why it is important to change fuel filters. It is not just for the dirt.


They say then that it is necessary to draw fuel through the filter by installing the filters/separators on the suction side of pumps, preventing the formation of an emulsion and enabling the water separators to do their work by the principles you have outlined. Presumably the pumps are doing the very thing that you explain is difficult to do.
Pumps that I know "push liquids" through a filter. If they try to suck it through the filter, the pumps cavitate (emulsifying air into the liquid) and are limited to applying a pressure of only a few psi across the filter before a vacum is created inside the filter. If pumps cavitate and emuslify air, then the fuel/water seperater now becomes a fuel/air seperater. Entrained air is even worse for the injecters than water.

That being said, if the filter was large and porous, and the driver did not instantly demand a lot of fuel, any liquid water in the fuel would not be emulsified and none of it would become trapped inside the filter media. It would all coalease at the bottom of the fuel filter housing where it will slowly dissolve until the cannister was cleaned out.

However it would be best to have liquid water coalease where it can be easily removed (like the bottom of the fuel tank) before it goes to the fuel pump and then to the filter.


Let us not forget, such a systems does not guarrantee that water does not enter our fuel filters in the emuslified form. The pumps at the fuel vendor will gladly emulsify the water for you if their tank is contaminated.


Many older diesels do in fact have lift pumps in the injector pumps that draw fuel all the way from the tank instead of having pumps in the tank that feed the injection system.
There must be a filter though before the fuel enters the injecters. Many of these older diesels were fueled from tanks under the owner's control and maintenence. Not so for our cars.

Ideally our cars should have a spigot at the lowest part of the fuel tank or at least a small lift pump to remove whatever liquid is there. This would allow water to be removed before it get sucked into the pumps and then emuslified. One it is emusified, then one has to rely on the fuel filter to do the seperating and that always guarantees that dissolved water will get through where it can cause corrosion.

If I were to ask VW to do just one thing, it would be that.
 

piper109

Veteran Member
Joined
Dec 6, 2003
Location
Ashe Co NC
Well I think this discussion is getting a bit over the top and we are getting away from the real world practical requirement of trying to make our fuel supply as clean and water free as reasonably possible without going to either scientific or perhaps silly extremes.

Its true that pumps can cavitate when sucking but they can tolerate a little negative head without whining or tearing pieces off their mechanisms.

The info I have read is available from Racor and Fleetguard sites and I do believe that it is written following technical if not scientific research.

I am an engineer myself and I have had to deal with and follow behind sales people who sometimes don't hesitate to make claims that sound good without being good and sound.

Its been shown that water separators work better when the water and fuel mix have had a chance to coalesce. Its also true that in a moving vehicle fuel tank that has just been pumped full of fuel that there is little chance that any coalescence can take place.

I think its likely that there is always a water in fuel to a greater or lesser degree and the HPFP can probably give good service life when that content is very slight. How much and how to measure it escapes me.

I wish to improve my chances by passing the fuel through a filtration system that can perhaps catch the results of sloppy fuel handling or storage.

i believe it has also been shown necessary to improve the lubricity of our fuel to prolong the life of the injection system and I intend to take reasonable and easy steps (avoiding the extreme) to do that also.

There are good contributors to these forums and I am thankful for the efforts and wisdom of many of them.

Steve
 

specsalot

Veteran Member
Joined
Jul 30, 2011
Location
Florida
TDI
Currently none
All of us live with some hope that VW will be forced to retrofit improved HPFP's on our vehicles. The more likely scenario seems to be:

1. The NHTSA will not reach definite actionable conclusions that prompt a response from VW / Bosch.

2. VW will default back to assigning all HPFP failures to owners accounts.

It makes sense to go after the low hanging fruit. Filtration and lubricity improvements make great sense.
 

CedarPark68

Veteran Member
Joined
Nov 14, 2010
Location
Texas
TDI
2011 Jetta TDI Wagen
Cheers to you 2Micron!

Yes, many people to offer up ideas, many people to be scared of anything that VW has not delivered to them in the car they purchased.

None but you to do something on a CR ... so Cheers to you again.

The true water separation alone is worth every bit of praise.

I have an older HPFP which was kindly given to me by OilHammer... I will gladly ship it to you to shamefully entice more of your efforts.

PM me if interested.
 

2micron

Vendor
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Mar 23, 2012
Location
Canada
TDI
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Thanks CedarPark,I appreciate the kind comments.
Many others from this club have been involved and provided fantastic research on the pumps. We must thank and acknowledge all involved. Dweisel was on one of the pioneers and was one of the first to take the pump body to a shop for nicasil coating. kudos to him.
I will continue with different bore options and roller/ shoe ides.
The filtration set up and kits i have been experimenting with are very simple and effective. Glad to see others (piper) are experimenting with other ideas and extend the best to them and offer help as always.
The pump you have from oilhammer is very valuable for testing and experimenting, I will PM you for discussions.
Thanks to all,
All the best,
 

red64chevelle

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Jan 17, 2007
Location
Coventry, RI
TDI
mk6 Golf TDI, mk4 Jetta TDI, Beetle TDI
Hello MayorDJQ,
Yes you are correct, this smaller filter is after the pressure relief valve. It only captures contaminants after the rail and prevents them from circulating to the tank. The line pressure is 9 psi, 159 litres per hour. (42 us gal/ hour)
.
Thanks again for the comments, and sure,
red64chevelle, experiment with a lighter setup, just ensure your filters meet the flow rates posted earlier.
Thanks!!!
Well, it has been just under 8k using the filter and all is well.

I noticed a little chaffing on the hose that runs up against the engine cover. I may just end up trimming the cover a bit.
I drained the filter after changing it, and there is no water in it. So the primary filter is working as a water separator (or I have been REALLY lucky for about five months).
I think this might still be a great idea for anybody that is going to go outside their warrantee, because as I understand it, by having the filter where this one is, the tank and fuel lines will not have to be flushed when the HPFP fails.
I would still like to find a used main fuel filter housing to weld a bung on it to add a drain valve on to it to remove water.
 

Flyn G

New member
Joined
Aug 24, 2012
Location
Conway
TDI
looking
Water in diesel, yes I've seen it in my first diesel vehicle which was a 97 Ford Powerstroke. It had a separator built into the filter bowl. I had it come on 3 or 4 times over the years. It seemed to need a certain quantity to trigger the light as most of the time it would flicker as I was going around sharp corners at highway speeds. It only came on and stayed on while driving once. A simple press of the lever would sump the bowl and away I would go. My second diesel was a Jetta TDI which never told me it has water in it's fuel but it did stumble upon occasion. It always kept going so maybe some of those ubber smart German engineers were looking after me. This has been a good long while ago so cleaner fuel could be available, but I doubt it. Manufacturing, refining, etc are all prone to the errors of us humans with occasional help from nature.

On the other hand I have some experience with Jet fuel and testing for water. Specific gravities or water and kerosine are very close so any disturbance of aircraft or fuel truck is enough to emulsify low volumes of water to the point of not being visible to the naked eye. Therefore water test kits using a water sensitive strip, paste, or tablets are the norm for flights being fueled prior to heading out over water. I never saw any contamination personally but I have read this past week of a accident report listing fuel contamination and engine surging as the beginning of the chain in the accident. In this case we would be talking gross contamination not just a little bit of suspended water. The primary concern of aircraft in flight is water separating in the tank and freezing into crystals that then block fuel inlets. We don't have water in the tank monitors either but some jet aircraft have fuel heater/oil coolers and Fuel Filter impending bypass monitoring devices as a way of dealing with the issue.

Should VW have a water separator and warning. Yes I think so. If for no other reason than to give you a chance to shut if down when the local station has a cracked tank that fills with rain water. This happened here this past year and caused multiple cars to stall one afternoon here in town. Imagine if that had been diesel instead of unleaded. Ouch!
 

MayorDJQ

Top Post Dawg
Joined
Dec 4, 2001
Location
Williamstown, Mass
TDI
'10 Golf 2dr 6m, sold.
The trouble with adding warning lights is that 98% of owners will have no clue what the light is telling them. The oil pressure light is the perfect example, followed closely by the low tire light. Most people are too lazy to open the owner's manual or are too stupid and will continue to drive when a warning light comes on.
 

Cleenlivin

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Sep 8, 2008
Location
So Cal
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2009 Jetta TDI Sedan (DSG) boughtback, 2004 Jetta TDI Sedan (Tiptronic), 2004 Jetta TDI Sedan (5 speed)
Updates?

I recently saw another HPFP thread on the Mark V forum. Do you have any status updates regarding the performance of this filtration. I think many members are becoming more interested in a possible solution to the HPFP problem each time they read of a failure out of warranty and the havoc (cost) it wrecks on the cars engine/fuel system.
 

2micron

Vendor
Joined
Mar 23, 2012
Location
Canada
TDI
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Hello Cleenlivin, the water separation part of this experiment is only a preventative measure, with minimal value. The more beneficial value of the experiment is the fine filtration offered by the larger pre filters added before the HPFP. The return filter is simply a means to capture any debris from getting back into the fuel tank, during HPFP normal wear and failure. The return filter is simple and cheap insurance to prevent tank contamination only. This will not save the pump. Thousands of miles have been logged with. no issues, by a few members here.
The only issue with the addition of fine filtration before the HPFP is the cost. I have logged over 15k on the fine filters and quite often inspect the internals of my pump, with fantastic results.
.
This will not save the pump. Bottom line. It is a preventative measure to help prolong pump life, contain damage and as an additional benefit, offer water separation. The OEM filter is only rated at 13 micron (nominal). Any additional filtration will certainly help, but it will not save the pump.
 

Cleenlivin

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Return Filter Only?

Hello and thanks for the update. If I understand correctly, the return filter comes after the HPFP. I there is a problem such as a dreaded fuel pump failure, it could possibly filter out contaminants before they circulate throughout the fuel system and engine? If so, it seems like a very worthwhile investment/modification. Replacing a HPFP isn't cheap but a better alternative than replacing the entire fuel system, injectors, etc. How is the fuel flow and performance with the added restriction in the system?

I'm interested in learning more.

Thanks
 

2micron

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Canada
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Return Filter only

Hello again Cleenlivin, the return filter kit as shown in red64chevelle's above post is simply a means to contain particulate after the HPFP and fuel Rail return line to the fuel tank. This is the low pressure return side only. It will do zero for the HPFP, injectors, injector lines, rail and rail sensors. However, it is effective at keeping our systems natural debris (HPFP wear) out of the fuel tank, lift pump, auxiliary pump and lines. The filter is also rated slightly better than the factory filter.
Lately fuel tanks have been cleaned under warranty, after a dreaded HPFP failure and looks like one member here has been quoted around $350 for their dealer to clean rust sediment from thier tank.
.
There have been no issues with flow restriction and no holes are drilled in the car, or no factory lines cut.
There is a suitable filter for less than $200, for the high pressure side of the system, but this would involve some experimenting.
http://www.highpressure.com/products/valves-fittings-tubing/high-pressure-valves-fittings-and-tubing/line-filters-check-valves/line-filters/

Hope this helps,
All the best
 
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red64chevelle

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Is there a kit for the return filter setup or is it a pieced together kit?
Contact 2micron to see if he is selling kits. I got one from him months ago. I have been very happy with it. As he has stated, it does not remove any water, as the factory filter gets all of that.

After about 8k miles, I drained mine completely into a cup and let it sit. No water was present.

My opinion is that it is mainly a good idea for those out of warrantee to limit the costs when (not really if) the HPFP fails and does increase the filtering of the fuel to limit wear caused by wear particles in the fuel coming back into the pumps.

If I am missing anything, I am sure someone wil chime in.

I still plan on installing a bung on the bottom of the OEM fuel filter housing to drain any water in that filter as soon as I find a housing for short money.
 

Smokin_Joe

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2011 Golf TDI Highline returned for refund
I forgot another one:

* Improper run-in at the factory.

I would guess that Bosch does a bench test of these little piston-engines at their assembly lines, before being shipped to VW. A full operational test before it leaves their facility. It may be that certain batches have had problems. Maybe due to improper machine settings, or assembly personnel error.


I think it's much more likely to be something like this than some sort of wear due to the fuel lubricity and/or minute particles in the fuel. Why have some HPFP's failed at only 7k miles? They have had such a small amount of fuel run through them -- that's only 10 or so tanks. You're telling me that 10 tanks of quality fuel, filtered to the VW filter specs, was enough to kill an HPFP? And there are many, many CR TDI's with 50k, 80k, 100k+ miles on them that are running just fine, having filtered much more fuel, and likely even seen a few tanks of lesser quality fuel?

No, I'd be much more willing to bet that there was a pump tolerance issue, or mis-hardened pistons, or some occasional issue with pump assembly or run-in that's the cause of the HPFP failures.

As I said, you're free to filter out the minutia if you like. But as for me, I think I'll put my faith in the VW/Bosch engineers to root-cause the issue, rather than slap on band-aids that no one has any good reason to believe will be beneficial.
Haven't read to the end, of this thread, but this quote caught my eye.
It has been a couple of years and well I think they aren't trying as hard as they should on getting to the root cause. With their technology and expertise I figure a couple of months to address an issue this small, if anything it seems to have gotten worse.
You have had some good things to say as well as a number of other people but I think your faith might be a little miss placed.
I'm thinkin 2micron might be onto something a little more concrete in the way of preventative maintenance till the engineers finally get around to getting to the root cause.
Another thing he is doing is engineering a replacement for the root cause. Replacing the cp4 with a cp3, an he seems to be doing on a much smaller budget.
 
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frugality

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Sep 19, 2003
Location
Spring Lake, Michigan
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none, 2016 GTI
Haven't read to the end, of this thread, but this quote caught my eye.
It has been a couple of years and well I think they aren't trying as hard as they should on getting to the root cause. With their technology and expertise I figure a couple of months to address an issue this small, if anything it seems to have gotten worse.
You have had some good things to say as well as a number of other people but I think your faith might be a little miss placed.
I'm thinkin 2micron might be onto something a little more concrete in the way of preventative maintenance till the engineers finally get around to getting to the root cause.
Another thing he is doing is engineering a replacement for the root cause. Replacing the cp4 with a cp3, an he seems to be doing on a much smaller budget.
(My statements are my opinions based on my experiences)
Let's see, this thread was in progress back in 2012. Failure rates were low back at the launch of the vehicle, and they are even lower now. I'd say that things are improving.

I'm an automotive engineer. I know how the process can be far from perfect. But I get a kick out of armchair quarterbacks who think they know how automotive engineering works.

Also keep in mind that the discussion back in 2012 was on adding extra, finer-filtering pre-filters to hopefully prevent HPFP failures. That's what the comments are referring to, and I stand by those comments. When you look at 2micron's current kits, they aren't for pre-filtering, but post-failure containment. Different discussion.
 
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