Water fuel separator

2micron

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Extra Filtration road hazard strikes

Hello rrolsbe,
Thanks for the questions and constructive comments!!
Originally posted by rrolsbe:
After viewing your pictures, I have a comment and a question. Looks like the unit mounted to the uni-body frame under the fender skirt mounts to the same place as the mounts do for at least some of the aftermarket skid plates (like my DieselGeeks Panzer plate). Looking at the picture, it looks like the driver side front skid plate mount should bolt on under your filter mount assembly. This would drop the driver side of the skid plate the thickness of your mount (looks like 1/8 to 1/4 of an inch?). I wouldn't think that drop would be problematic but if it where maybe Jim at DieselGeeks would provide a slightly shorter drivers side mount as an option? Now to my question, how well do you think your modification (mounted to the uni-body frame is protected from potential strikes from road hazards etc.. ? I realize this post is premature but if your design proves to be fruitful these issues will apply.

Regards, Ron

PS... I assume you primed the fuel system using the VAG computer interface after installing your fuel system modifications. Did you have any problems priming the fuel system?
.
Good thought, yes the Panzer plate would now be 3/16" lower than original on the Drivers side.
The lowest part of the filter units are positioned 1-1/2" higher than bottom of the factory plastic wheel well lower air scoop. - higher than the drivers side lower inter cooler hose.
With the inner fender removed in the pictures, yes they look quite ready for strikes, but they are well back from the covers and protected nicely from strikes when all the covers are replaced.
.

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I have devised a simple catch containment system to direct any leaks away from the tire. The other option is to install the 45 series filter elements rather than the 60 series elements (screw on). They are 1-1/2" shorter, but would require more frequent replacement intervals. - 8000 miles.
Good comments and much appreciated!!
As for priming:
This was very simple by manually energizing both lift (tank) and boost (aux.) pumps for 1 minute, 3 times, with a rest period in between. All three newly installed filters have bleed screws, to remove air bubbles while priming. Our pumps provide major Flow!!! No issues and instant start.
All the best!!
Thanks,
 

specsalot

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I have to agree with frugality regarding the merits of filtration. That said, I'm not ready to criticize folks willing to turn a wrench in the name of tackling issues that Bosch / VW engineers seem unwilling to acknowledge or address for existing owners. FWIW I'm also a degreed engineer... Beyond HPFP failure patterns filtration issues would also be suggested by higher injector failure rates. No one seems to be reporting a lot of injector failures.

As long supplemental filtration has been properly sized there is no harm done. Better water filtration w/alarms can't hurt as it might get one to pull over and stop before the engine stops on it's own due to water contamination. Trapping HPFP debris with a catch filter represents a significant contribution as it might reduce swarf in circulation.

Per 2micron's test data three things are very clear:

1. Restrictions in the fuel supply to the HPFP translate into reductions in recirculation flow.

2. The overflow valve does a great job maintaining HPFP supply pressure regardless of changing supply flows. (Of course - that's what it was designed to do)

3. The bulk of vehicle fuel recirculates through the HPFP in ~20 minutes or less.

I believe it is not a coincidence that VW redesigned the fuel system of the Passat to eliminate both the aux fuel pump and the fuel heating valve / recirculation circuit through the fuel filter. Issues with either of these components could impact fuel recirculation volume. A stuck closed fuel heating valve could also lead to elevated HPFP supply pressures. Elevated HPFP supply pressure might make it difficult to control CR pressure potentially over stressing pump components. HPFP's that experience significant reductions in recirculation flow might experience thermal transients (i.e. overheating) that contribute to failure. Bosch automation does not monitor return fuel temperatures, only the temperature of fuel entering the HPFP.

2micron - Killer Pic's - Keep us posted on your ongoing experience with this system. I think we're waiting for the next installment where you eliminate the VW filter and it's internal fuel heating valve. Since you are up north, you might consider the inline jacket water fuel heater for winter use to supplement the electric heaters under cold conditions.
 
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dweisel

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dweisel isn't diesel anymore!
I'm not saying that VW engineers know everything. But they and Bosch have data from thousands of hours of actual testing -- with different fuel qualities, different filter elements, different ambient temperatures.... If you expect VW/Bosch to somehow be perfect, then you're expecting them to be God himself. But you're telling me that shmucks on a web forum who have no evidence or data are going to solve the issue by filtering out infinitesimal particles in the hopes of preventing HPFP issues...................



Please refer to the definition of: hyperbole .
I think 2Micron is just trying to give his fuel system the best protection he can install on his CR engine. He has also provided the club with some valuable info we did not have before. I commend him for his efforts.

I think referring to anyone here as "shmucks"is pretty condescending on your part. I had to look it up myself as its not even in my vocabulary. My sincere apologies if you were using schmucks as a hyperbole to discribe some of us forum members without an engineering degree.
 
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piper109

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This an interesting thread that I intend to follow closely. I am on the point of buying a 2012 JSW and I plan on upgrading the filtration by the neatest way possible.

Incidentally, "shmuck" in German means decoration or jewelry. I'm not sure how the NY Yiddish derogatory slang term originated.
 

dweisel

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dweisel isn't diesel anymore!
This an interesting thread that I intend to follow closely. I am on the point of buying a 2012 JSW and I plan on upgrading the filtration by the neatest way possible.

Incidentally, "shmuck" in German means decoration or jewelry. I'm not sure how the NY Yiddish derogatory slang term originated.

Schmuck or shmuck in American English is a pejorative meaning an obnoxious, contemptible or detestable person, or one who is stupid or foolish.

That portion of one's penis which is cut off during circumcision,a Yiddish term

Ether way you take it.....................not a nice comment.
 

Elfnmagik

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He didn't need to resort to name calling. Could have just left it at, "this is all a bunch of schmegegge" and still maintained his penchant for Yiddish.
 

MayorDJQ

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I would have figured DFMEA stood for something else, but I'll refrain.

The "schmucks" on this website have figured out a lot of solutions to problems that the High & Might VW Engineers either couldn't or were unwilling to solve. I remember when dealers were replacing entire turbo setups on AHUs and ALHs when only a vacuum line was VNT actuator needed.
 

specsalot

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So if failing HPFPs isn't a filtration or wear issue, then what is it? Those metal shards are coming from somewhere. I don't think Bosch dumped confetti into the fuel system as decoration.
Failure thread discussions suggest those metal shards inside the HPFP get created there due to pump issues. The picture below shows contaminated washings that came from an HPFP that VW said had failed. The pump showed no significant evidence of failure. These washings imply something was a muck in the fuel system of this vehicle. A catch filter between the HPFP returns and the stock VW fuel filter should reduce the amount of material migrating through the system. We are unfortunately stuck with only anecdotal evidence. None of us has the resources of Bosch or VW to investigate this issue. What every they know, they aren't saying much. It does appear that they are quietly trying to engineer themselves out of this issue. Nothing wrong with that except it does nothing for current owners. Flash illumination was used to make the metallic visible against the black background of the drain pan. I used fresh clean diesel carried in a new plastic fuel can. Washing was done in a new oil drain pan. The yellow specs are unfortunately detached rubber bits from the bulb of an old turkey baster used for the flushing work.

 
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MayorDJQ

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Right, a filter in the return(s) would catch a lot of that, but I find it hard to believe that those particles couldn't cause problems at the injectors. Is it not possible that a shard could cause an injector to stick open and overfuel?
 

dweisel

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dweisel isn't diesel anymore!
Right, a filter in the return(s) would catch a lot of that, but I find it hard to believe that those particles couldn't cause problems at the injectors. Is it not possible that a shard could cause an injector to stick open and overfuel?
The couple of injectors from failed hpfps that I've disassembled and looked at always had those fine metal particles in them. Thats the reason VW replaces everything including the injectors. What affect these particles would have on an injector I do not know..................but it can't be good.
 

Softrockrenegade

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I would believe that any particle fine enough to pass through the fuel filter would be a non issue for injectors but the problem resides in the buildup of this fine metal slurry mucking up the roller .
 

MayorDJQ

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The couple of injectors from failed hpfps that I've disassembled and looked at always had those fine metal particles in them. Thats the reason VW replaces everything including the injectors. What affect these particles would have on an injector I do not know..................but it can't be good.
So again, does anyone know any details about the CR injectors? Is it one orifice? Or 5 like on an ALH? What is(are) the measurement(s)?

I know I'm not an engineer, but if we can see these metal flakes, I'm thinking they're not in the "micron" range.
 

specsalot

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I don't have the specific details you ask. Here is a cut away from the 3L TDI narrative.

Injector description is rather complex. Basically the Piezo Actuator, Connecting Plunger, Valve Plunger and Switching Valve form a hydraulic circuit. This circuit is used to control pressure above the Injector Needle. Injection Needle movement is based on a force balance created across the needle by this hydraulic circuit.

The injector internals are protected by a pin type filter. This filter basically forces incoming fuel to go through direction changes and pass through narrow flow paths. The idea is to trap large contaminants, keeping them out of the injector body. This should protect our injectors if this material was to get this far along in our fuel system.

Good working fuel injection requires at least 3 things to occur:

1. Clean injection nozzle opening.

2. Good atomization (i.e. proper nozzle supply pressure, no plugged injection holes, holes not worn out, etc).

3. Clean injection nozzle closure (i.e. no indifference / leakage below the popping pressure).

These TDI injectors are very fast / precision units. The piezo controlled hydraulic circuit allows these nozzles to operate for the most part independently of fuel supply pressure. This fuel system will probably not tolerate any kind of injector indifference at all.

I don't believe the stuff I saw in the drain pan was small enough to have any chance of reaching the injector nozzle tip. If this contamination reached the switching valve, I doubt the injector would operate for very long.

An open question would be whether this contamination is routinely getting far enough through the injection system to reach the pin filter.

I doubt this as well. If this material were to become lodged in the discharge check valve of the HPFP, delivery would go to zero. Pictures posted in the failure thread show that the screen which protects the inlet to the fuel metering valve accumulates a lot of these metallic contaminants during a failure. This probably keeps the balance of the fuel system healthy for a long time. Symptoms of a failure do not manifest until fuel delivery from the HPFP fails.
 
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specsalot

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MayorDJQ - You are right - Most of this metallic contamination is not at the micron level. The stuff that gets recirculated out to the fuel tank in a failing system is probably stopped by the stock VW fuel filter. The material that winds up on the clean side of the VW fuel filter (while the heating valve is recirculating back to the clean side only) gets trapped by the inlet filter screen of the HPFP.

From Wiki http://en.wikipedia.org/wiki/Micrometre

A micrometre (or micrometer) is by definition 1×10−6 of a metre (SI Standard prefix "micro" = 10−6). In plain English, it means one-millionth of a metre (or one-thousandth of a millimetre, 0.001 mm, or about 0.000039 inches). Its unit symbol in the International System of Units (SI) is μm. The latter may be rendered as um if Greek fonts are not available or not admissible. "Micron" comes from Greek: μικρόν mikrón, which means "small".

The term micron and the symbol μ, representing the micrometre, were officially accepted between 1879 and 1967, but officially revoked by the ISI in 1967.[1] In practice, "micron" is a widely used term in preference to "micrometre" in many English-speaking countries, and in American English the use of the term helps differentiate the unit from the micrometer, a measuring device, which would otherwise be spelled as a homonym with micrometre. The term "micron" has particular currency in science, and is extensively used in most English-speaking countries in the fields of geology, biology, physics, astronomy, machining, and the semiconductor industry.
 
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dodgediesel

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While I agree with frugality that tolerances and hardening specs can affect the rate pumps fail, keep in mind that Bosch has been making automotive parts for 125 years, and diesel injection pumps for 85 years. I think they have a grasp on these pretty basic engineering ideas. Also, if tolerancing was truly an issue, Bosch would have certainly fixed their manufacturing lines by now.

I think that the variability in fuel (solid particles, water, etc.) along with inadequate filtration would cause a much greater effect on the pump than the variability in manufacturing, especially since this problem doesn't appear in other makes that use the same system.
 

specsalot

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More for folks wanting details more from the 3L TDI narrative about injector operation:

"With the application of a voltage, the piezo actuator expands by up to 0.0012 inch (0.03 mm)."

Injection starts when pressure is bled off the control chamber via the switching valve.



Injection ends when Control Chamber pressure is built up after closure of the switching valve.



With these kinds of small movements only a small amount of trash would be game over for these injectors. If Bosch can design something this precise, it's hard to understand what the issues are with the HPFP. It's more than filtration, but keeping trash and water out should surely be a help.
 

specsalot

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The full narrative for the 3L can be found at the following link. It provides the above details regarding fuel injectors. The technology can't be much different on the 2L CR TDI. Took me a while to find the link that was originally posted by Nimbus. The pdf is still on line, but who knows for how long.

http://152.66.93.29/audi/download/vw/Engine/TDI/3L TDI.pdf
 
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MayorDJQ

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According to the diagrams in the self-study guide, the filter screen is between the Aux pump and the HPFP. How is it going to stop particles from getting to the rest of the fuel system? Just as particles precipitate to the bottom of the fuel filter canister, I would bet it also collects on the bottom of the fuel tank. If it gets sucked up by the lift pump, the fuel filter should stop them. But is the filter screen a finer filter than the regular fuel filter?

I would have to think that if the HPFP is shedding metal, some of it will go into the rail, and some of it will go out the low side return. Since so little fuel is injected as compared to what heads back to the tank, maybe the injectors don't see to much of the particles.
 

specsalot

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The filter screen between the Aux Fuel Pump and the HPFP is likely there to protect the HPFP in the event of failure of the fuel filter element or disintegration of the Aux Fuel Pump. The fuel filter is much finer than this filter screen.

The Aux Fuel Pump I've opened up looks like it could be a source of metallic material in the fuel stream.



As I've suggested, there's a reason VW is choosing to eliminate this pump in favor of a higher output pump located on the inlet side of their fuel filter. This thread is supposed to be about filtration. I tend to get off topic easily. To be fair to the OP and others lets move questions about HPFP failure over to the failure analysis thread. I will repost your questions and reply in the failure analysis thread.

What is know is that ~ 99% of HPFP's are not failing. The vast majority are operating with stock fuel filtration. Most HPFP failures do not show any significant symptoms until failure occurs.
 
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2micron

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Return fuel heating valve testing.

From specsalot:I believe it is not a coincidence that VW redesigned the fuel system of the Passat to eliminate both the aux fuel pump and the fuel heating valve / recirculation circuit through the fuel filter. Issues with either of these components could impact fuel recirculation volume. A stuck closed fuel heating valve could also lead to elevated HPFP supply pressures. Elevated HPFP supply pressure might make it difficult to control CR pressure potentially over stressing pump components. HPFP's that experience significant reductions in recirculation flow might experience thermal transients (i.e. overheating) that contribute to failure. Bosch automation does not monitor return fuel temperatures, only the temperature of fuel entering the HPFP.
Hello all,
Just an update on testing and elimination of the Return Fuel Heating Valve, within the stock fuel canister.
These tests are done in water, low air pressure to simulate flow.
The purpose of the tests were only to determine at which temperatures the valve re-directs fuel back to the tank and an attempt to determine the thermostatic effect on the HPFP.
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This is the underside of the fuel filter canister lid. The White item in the middle is the valve that directs return flow back to the HPFP, or returns fuel back to the tank.
This is the Valve Fully Open - Cold and Returning fuel to HPFP:

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This is the Valve Closed - Hot and returning fuel to Tank:

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Here are the Temperature Specs (Degrees Fahrenheit):
55*F - Fully Open - 100% return to HPFP.
59*F - Starts to move - 100% return to HPFP.
68*F - 1/16" Movement - 100% return to HPFP.
82*F - 1/2 way Closed - 100% return to HPFP.
89*F - 3/4 way Closed - Return to tank begins, 98% return to HPFP.
112*F - Closed - 25% return to HPFP.
125*F - Seated 100% - 5% return to HPFP.
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The valve doesn't seal off the return to the HPFP 100%. The in-situ flow rates will be slightly different due to the slight pressure differential between the in tank pump (canister side 12psi) and the Rail return side (9psi). The temperature values at which the valve actuates will remain the same though.
.
Looks to me that VW is attempting to thermostatically control the incoming Fuel Temperature to the HPFP around 90*F.
I originally thought this system was for quick heating of the fuel at cold temperatures to avoid freeze up of fuel. Seeing these numbers leads me to believe it is attempting to heat the HPFP up to 90*F quickly, then latent heat from the motor will maintain the pump at coolant temp.
One issue to note is the valve is very slow to respond to temp changes. This may become an issue in overheating the Pump.
One of our members stated problems with a similar set up on earlier generation TDI's. Anyone have any thoughts???
All the best,
 

specsalot

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Nice pictures and measurement data - Well Done

To get some idea's of fuel temperatures I made the following measurements last August using an IR thermomenter.

HPFP Body Temp ~ 142 DEG F
Fuel Return Line Temp ~ 153 DEG F (measures @ return line from injectors)
Fuel Filter Body Temp ~ 137 DEG F

What I need to do is some VCDS logging of fuel temp to the HPFP under various conditions to see how much of a temperature variation occurs. Based on your overall flow measurements the entire tank moves through the system in ~ 20 minutes max. Under summer conditions, the fuel tank probably acts a bit like a radiator dissipating heat from the vehicle fuel.

This is one more reason not to run the tank to a near empty condition before refueling. I tend to use the same station all the time and typically fill up when my tank is somewhere between 3/8 and 1/2 full.
 

specsalot

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Today I made an ~ 300 mile RT. I brought VCDS and did some fuel temperature logging. The graphs are not real interesting but I will summarize results below.

Logging was started from cold start with the car in my driveway. The majority of travel after ~ 10 minutes time was all interstate with cruise control set at ~ 118 km/hr.

Outbound Leg Departure (fuel tank ~ 70% full)
Ambient Air Temperature: ~ 16 DEG C
Fuel Temp ~24 DEG C
Coolant Stabilized @ ~ 94 DEG C in ~10 minutes driving time
Fuel Temperature Stabilized @ ~ 27 DEG C in 30 minutes driving time

Outbound Leg Arrival
Ambient Air Temperature ~ 24 DEG C
Coolant Temperature ~ 96 DEG C
Fuel Temperature ~ 37 DEG C

Return Leg was not logged from start up. The car was refueled and up to normal operating temperatures. Logging began on the interstate portion of the run. Cruise control was set at ~ 118 km/hr.

Return Leg Departure
Ambient Air Temperature ~ 28 DEG C
Coolant Temperature ~ 96 DEG C
Fuel Temperature ~ 36 DEG C

Return Leg Arrival
Ambient Air Temperature ~ 26 DEG C
Coolant Temperature ~ 96 DEG C
Fuel Temperature ~ 40 DEG C

I'm not ready to draw strong conclusions based on this data. One thing that was clear in the loggings was that fuel temperature tended to jump up as the vehicle slowed down from highway speed. The implication is that convective heat transfer due to air flow in the engine compartment plays a role in fuel temperature. The temperatures recorded in post 81 above were taken in my driveway after stop and go traffic. More loggings are required to fill in the picture here.
 
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Niner

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Jun 3, 2011
Hello Everyone!!
First timer here and glad to see such a nice “Family” related to TDI’s.
I just bought a 2010 Wagon, 6 speed about 2 weeks ago from a very good VW dealer in Ottawa Ontario. The car was traded in with 50,000 km’s on a new DSG wagon. After driving it 200 km’s, I set about adding better fuel filtration, in attempts to prolong HPFP life.
This is my first TDI, but not my first diesel. Most diesel’s have a means to separate and detect water in the fuel, as well as fine micron filtration. Modern CR engines require 2 Micron filtered fuel. To properly achieve this, primary and secondary filtration is one of the most accepted practices. As for water in fuel, this may not be as common today due to better practices, fibre-glass in ground storage tanks as well as plastic tanks on our cars (to reduce condensate), but it can still happen. My wife’s Cummins Diesel was only weeks old when it got a helping of water. The water separator and warning light prevented disaster. A simple filter drain, then a $45 filter had it back on the road. The station was a well used and a reputable company, but unfortunately, water still made it into their tank. Dweisel’s comment is correct, “Every fuel system needs all the protection available.” It doesn’t matter if your fuel has been refined at the best facility in the world, contamination is possible between transfers. It has been proven, our HPFP’s have issues, so water separation seems like a worth while investment and appears to be a simple item to solve.
Back to filtration:
The stock VW / Mann filter appears to be 7 micron. - any thoughts??
Regardless, if it is less, this would be hard to achieve with a single pass. Again, our HPFP’s seem to be having a tough job with our fuel. Better filtration will not solve the HPFP failures, but it will definitely reduce the risk and possibly prolong the life of the HPFP. This also seems like a worth while investment and appears to be a simple item to solve. Our systems have been designed with critical pressures and flow rates, which, if altered, must be within acceptable parameters.
Here are my car’s fuel system specs, proven by testing with ½ tank fuel, warm spring temperature:
Stock configuration:
“In tank Lift Pump” - 12psi, flows @ 195 litres per hour. (51.5 us gal/ hour)
“Aux. Boost Pump” - 62 psi, measured right at HPFP.
“Return line to tank, before Temperature loop @ idle” - 9 psi, 159 litres per hour. (42 us gal/ hour)
Enjoy the following pictures, showing the added in line supply filtration and filtration, after the HPFP. Those are Racor 400 series filters / separators, mounted under the drivers headlight. Primary is 10 micron, secondary is 2 Micron. Primary has an improved WIF sensor, eliminating the “phantom“ signals of the past. Both bowls have heaters and water drain ports.

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Racor 400 Series Separators. 10 Micron Primary, 2 Micron Secondary. Heaters, Improved Water in Fuel Sensor and Drains.

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Mounting Bracket, with Stainless 3/8" lines.

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Filters mounted under drivers headlight, using stock studs. No holes drilled or any alterations to body or frame. Plastic Fender wells removed for Clarity. When the Belly pan is removed, Filters are easy to get to, otherwise, small holes are drilled and plugged in belly / pan to access drain valves.

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Here is the Filtration set up after HPFP, going back to the tank, showing Differential Pressure Gauges to monitor Filter Condition. This filter has a handy drain valve as well, to monitor contamination from our Famous Aluminum Bore / Soft roller HPFP.

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Temporary Gauge during testing after Aux. Boost Pump. 62 PSI at manual energizing, idling or 3000 RPM's

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Here are the fuel system specs, with the added filtration:
“In tank Lift Pump, with primary 10 micron and secondary 2 micron filtration” - 12 psi, flows @ 180.5 litres per hour. (48 us gal/ hour) - 7% decrease in flow, from stock.
“Aux. Boost Pump” - 62 psi, measured right at HPFP. - No change from stock.
“Return line to tank, after HPFP Filtration and after Temperature loop @ idle”- 9 psi, 159 litres per hour. (42 us gal/ hour) - no change from stock.
So the only concern is the 7% reduction in flow from the in tank lift pump, feeding the auxiliary boost pump. This does not mean I have to drive 7% slower, or will use 7% less fuel or will even starve the HPFP. This simply means a 7% reduction in feeding the stock fuel canister, which the Auxiliary boost pump draws from, thus, feeding the HPFP. In testing, results show the return line to tank flows at 9 psi, 159 litres per hour. (42 us gal/ hour) @ idle. The modified filtration system flows @ 180.5 litres per hour. (48 us gal/ hour)
What does all this really mean??
The stock system has 36 litres per hour (9.5 us gal / hour) surplus @ idle, returning to the tank.
The added filtration system has 21.5 litres per hour (6 us gal / hour) surplus @ idle, returning to the tank.
I can’t test pressures and flow rates under load, but road tests have so far been successful. The tank is now less than 1/8 and I have done long WOT runs, up hill with no effect.
For the 3.5 gallons per hour I have lost, I will gladly take the extra 2 Micron filtration and water separation. This also filters the return from the HPFP to the tank. This filter has a handy drain on the bottom to monitor HPFP degradation.
I will update with future tests.
If this interests you, please don’t just try any filters because you found them. Flow rates and pressures must be kept as close to stock as possible. Research flow rates and do your own testing. I would not recommend this project for everyone. I will happily discuss and help.
Negative comments are also appreciated, but the following have already been considered:
1.) Yes this will most likely void the warranty.
2.) 2 holes need to be drilled in the lower fender skirt / belly pan to access water drains.
3.) Heaters will draw 10 amps.
4.) Mounting of a indicator light needs a home on the dash. ( I will drill the blank switches beside the traction control switch)
5.) The filters are in a vulnerable location as far as leaks. A leak may drip onto the tire’s path. A simple catch containment system with a remote drain hose (Tide detergent bottle with a hose) is in the works.
6.) This modification does not seem to put any additional load on the in tank lift pump. It has been stated in past posts, it has a relief valve internally and testing has shown no change in it’s amp draw. There is also simply no change in audible pitch.
Please let us not bicker whether water separation and filtration is important or not. For me, I would rather reduce the risk, than worry about it or criticize others thoughts and beliefs. I have satisfied myself with this modification, more testing will prove it’s worth. I will update as miles add up!! I will post more pictures of the Filters if any one is interested.
The next step is to simplify the Return Filtration circuit. I can now Eliminate the Gauges and add more miles. The Stock Temperature Re-circ. is also on the Chopping block. The heaters in the Racor Bowls will soon take it's place...More testing!!
As far as the HPFP, an Ebay Pump is on the way, for dis assembly and modifications. Many a member has seen these pumps and made comments. It appears better materials are in order - at minimum, a steel liner.
But that is another post.
All the best,
All you need to do now is run it on some crappy US grade D2 with low lubricity to test how long it takes the HPFP to fail terminally. Canada supposedly has 460 micron wear scar fuel.
You also have no basis for the current condition of your existing HPFP on a used TDI?
Still, good luck with your experiments.
If filtration, filtration, filtration still yields a HPFP failure for you... then it's Shame on Bosch X3 for my signature line.
 
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2micron

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Hello Niner,
Canadian fuel is slightly better than US fuel, however we still have HPFP failures.
You also have no basis for the current condition of your existing HPFP on a used TDI?
Still, good luck with your experiments.
Sorry I didn't post this earlier:
The second day I owned the car, (early March), I disassembled the top end of the HPFP to develop a baseline for testing. No damage to the roller and cam was found, but slight scoring on the piston and bore. Car had 50,000km's. I have been inspecting the pump several times over the last few thousand Km's to find no change. The first thousand Km's I found minute amounts of what appeared to be aluminum in my return filter kit. Since then less and less has been found.
http://s1059.photobucket.com/albums/t428/2micron/
The reason for the Filtration additions and tests are to help prolong the HPFP life by helping to eliminate 2 important variables: water and particulate (dirt), not to solve the design issues of the pump.
The filters will not save the pump, but simply reduce the risk of water and dirt and will certainly help to prolong it's life.
I have been experimenting with several failed pumps, look for updates in the pump section.
All the best,
 

Jack Frost

Veteran Member
Joined
Nov 30, 2007
Location
Rural Manitoba
TDI
2009 Clean Diesel
Even if water is not in the fuel when you purchase it, it can enter your fuel tank as water vapour and condense as a liquid inside the fuel tank on a cold night.

All student pilots (at least I was) are trained have to drain a fuel sample from the fuel tanks of their aircraft as part of their inspection procedure before starting up. There was a bad accident here 13 years ago at a International Girl Guide Jamboaree where an airplane crashed with some Girl Guide Leaders on board. I read the accident report and water in the fuel tanks caused the engine to stall shortly after takeoff.
 

piper109

Veteran Member
Joined
Dec 6, 2003
Location
Ashe Co NC
I read mention of an improved WIF sensor from Racor. Can I find details of that somewhere ?
Any comparisons of Racor, Fleetguard, Stanadyne sensors ?
I'm looking at doing a two color LED indicator.

Thanks
 

2micron

Vendor
Joined
Mar 23, 2012
Location
Canada
TDI
None
Racor RK 30880E

Hello piper109,
Glad to see someone is interested in Water in Fuel!!!
You are looking for a Parker / Racor RK 30880E.
This is the new improved WIF sensor that is proven to be less problematic and gives no "Phantom" readings of the past.
http://www.parker.com/literature/Racor/7752_RK30880E_Probe_April2008.pdf
Any of the filter companies you mention are very good. It really comes down to what is easily available. I don't like to say one is the best.
Racor / Parker is the industry standard in Marine and highway tractors and always available.
Ebay is a fantastic source for the filter heads and sensors.
My kits use Racor only, but only because they are available at any Marine supply. Donaldson filters interchange in a pinch as well.
Love your idea about the LED set up. The above sensor comes with a 1/2-20 thread and a nice O-ring seal for less than $100. It is easy to hook up to any light bulb, buzzer or anything 12 volt, with no special modules or extras. You seem pretty handy, you could easily ad a bung to the bottom of your stock fuel filter canister and thread this in.
Cheap insurance!!
I have had great success with above sensor and racor in general.
All the best,
 

piper109

Veteran Member
Joined
Dec 6, 2003
Location
Ashe Co NC
Well I'm thinking of doing things a little differently.

I have a 1 week old jsw that I want to protect and also keep the warranty.

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.

The idea is to use a 12v Facet pump to draw (not pump) fuel through a good filter/water separator and put it back into the tank filtered at 2 microns. Its action is totally separated from the engine setup.

The OEM system would then stay intact and unmodified but I would know that is was drawing in filtered fuel that had been through a water separator. I would simply run the pump for 15-30 mins or so after each fill-up.
Yes it has draw backs and fuel would not be immediately filtered but then this system "should be" completely redundant anyway.

The two color LED would let me know that the separator was operational, changing color in the presence of water.

I could install this setup under the cover outboard of the right hand side of the spare wheel well. How and when to turn it on and off are not yet thought out.

Steve
 

2micron

Vendor
Joined
Mar 23, 2012
Location
Canada
TDI
None
Great to see someone interested in Water separtion!!!

Hello piper109,
Fantastic ideas and awesome that you want to work on your own new car, altering it to you're satisfaction. Good work!!!
Don't be discouraged by the others who believe this is not worth the effort.
If you add anything to your car and it satisfies and makes you happy, it is worth ten times the effort.
I have had my in tank fuel pump out several times for inspections and will post pictures of it, if it helps you decide where to add in and out line modifications.
To filter to 2 microns, it may be best to do it in 2 stages, (primary 10 micron, secondary 2 micron) prolonging the life of your fine secondary filter.
Sure, run it all the time?? The draw on a small facet pump is low and our HPFP's are always depositing fine contaminants back into the tank.
The return filter kits I have been experimenting with use a VW factory filter with Water Separation that may work in your application.
Great effort and thoughts, continue with your ideas!!
All the best,
 
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