Fuel Delivery Redesign: "Project Number Two"

[rbattelle]

Since I bought this truck I have been very concerned with longevity issues with regard to the CP-3 and injectors. Common rail injectors are significantly more prone to wear at the needle and seat than traditional jerk-pump type injectors. Add in the incredibly close tolerances required to generate 1600 bar in the CP-3, and you’ve got one very sensitive fuel system. I’ve heard (rumor) that Caterpillar is now running 2-micron filters as standard equipment as a result of their own research on the effects of particles <5 micron in US diesel fuel. We’ve seen the terrible experience some Duramax owners have had with their Bosch common rail systems. Until recently, I was too concerned with retaining my stock fuel system for warranty purposes to actually do anything about it. Well, events at my servicing dealer have revealed to me that I can no longer fully trust them to handle my truck, and I must take things into my own hands. In other words, I’m no longer concerned with my warranty. I have begun what I am calling “Project Number Two” (which is either a clever reference to #2 diesel fuel or a crude reference to a bodily function, depending on what you think of me and my idea!).



Project Number Two is a re-design of the stock fuel delivery system. I set forth the following goals in prioritized order:

1. Improve fuel filtration 5 times over stock (to 2 microns absolute)

2. Improve fuel delivery reliability and consistency (flow and pressure)

3. Improve serviceability



Along with these goals, I have defined the following objectives (in no particular order):

-Use industry standard components wherever possible

-Some consideration to affordability

-Minimize fears of fuel gelling/filter freezing problems in cold weather

-Modular construction

-Provisions for easy fuel transfers and testing

-Features for easy emergency service



Since my number 1 goal is to improve filtration I spent the most time researching filters and filter assemblies. Some of the filters I looked at were:

-FASS

-Fuel Preparator

-Nicktane (a 2-micron Caterpillar filter adaptor)

-Racor

-Dahl (as sold by Amsoil)

-Various options from Fleetguard

-TP systems (Motor Guard and Frantz)



Each of these have their pros and cons, and they're all outstanding systems. None of them offer me what I want in a complete package. The package I want is:

-2-micron absolute filtration (or better)

-Option for a 12v fuel heater

-Integral fuel booster pump

-Standardized connections

-Retention of the stock fuel filter

-Compatibility with 100% biodiesel

-Provision for a fuel pressure gauge

-Ability for future expansion (such as an Espar coolant heater)

-“Quick” component changes in emergency situations



I spent a lot of time trying to decide where the new filter should be positioned, and (to make a very long story shorter), I have decided that the best way is to mount my supplemental filter between the stock filter and the CP-3. As far as I’ve read, the industry standard in multiple filtration systems is to run them in series gradually stepping down in micron rating. Since the stock fuel filter is 10 micron absolute, then a 2-micron filter should be downstream of it to comply with the standard. In addition, mounting it after the stock fuel heater (a 300W unit) might allow me to forgo a second fuel heater for the supplemental filter.



Eventually, I came across the filter assemblies made by a company called Davco (www.davcotec.com). These guys make BIG filters primarily for the heavy truck industry. Their filters are purchased and re-branded by: Detroit Diesel, Mack, and Fleetguard. In particular, I’m referring to the Davco model 382 “Fuel PROcessor”. This filter is standard equipment on the following engines:

Cummins: ISX, ISM, M11, N14

Detroit Diesel: series 50 and 60

International: DT444, DT466, DT365

Mack: ASET Series and E7

Mercedes: MBE900, MBE4000

Volvo: all engines



It offers 3 fuel heater options: 12v, 24v, 120v. A 2-micron absolute filter is available from Fleetguard (P/N FS19761). It uses ½ NPT ports and has a 150 GPH capacity. Conveniently, it uses a “seeing is believing” fuel canister that is clear so it’s easy to see when it’s time to change the filter. Heated models have an integral coolant-fuel heat exchanger in addition to ports for an electric heater and thermostat. One problem: it retails for over $600. To get around that, I bought one from a gentleman on Ebay for $200 (unused but in need of a cleaning and a bit scratched up). Here’s a photo of the unit. It happened to come with a 120v heater. I have disassembled it for cleaning (and because I don’t like the thread sealant Davco used).



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Here’s a key to what you’re seeing:

1 - base

2 - drain valve

3 - base attachment screws

4 - 120v heater

5 - canister base collar

6 - canister top collar

7 - filter (it came with a Mack 7 micron filter installed)

8 - fuel bowl

9 - filter spring

10 - filter canister

There are 3 o-rings that I forgot to label.



This thing is BIG. Fully assembled it stands just over 16 inches tall and is almost 6 inches at the largest diameter. It uses only NPT ports of size 3/8 or ½. I have not decided on where to mount it, but am considering making a bracket to put it on the engine just above the CP-3 where the TPS is on early-build 2003 trucks. Not sure if engine vibration is something I should avoid, however.



In order to plan everything out, I came up with a schematic, shown here:



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Black items are components

Red items are connections

Blue lines are fuel lines

Letters label the fuel lines

Numbers label the connections



Fuel lines:

A - SS braided -6AN

B - SS braided -6AN

C - Factory rubber hose (3/8 ID)

D - SS braided -6AN

E - SS braided -6AN

F - Factory stainless 3/8 OD line



Connections:

1 - “Weber” fitting (M12x1. 5 to -6AN)

2 - -6AN to ½ NPT fitting (Summit Racing)

3 - -6AN to ½ NPT fitting (Summit)

4 - “Weber” fitting (M12x1. 5 to -6AN)

5 - Stainless steel disconnect (Swagelok)

6 - -6AN to 3/8 NPT (Summit)

7 - -6AN to 3/8 NPT (Summit)

8 - ½ NPT to 3/8 OD tube (Swagelok)



That list of connections is very generic: there are actually a total of 15 individual fittings that must be purchased in order to do this. I can certainly provide more detail and all relevant part numbers if there’s a desire for that here. Also, not shown here is a ½ NPT street tee that I’m installing at connection number 2 in order to facilitate a fuel pressure gauge (as an aside, that port could also be branched to provide fuel to an Espar unit).



So far I have my Davco filter and I have my Swagelok fittings on order ($161 worth of fittings). I went with all stainless steel because brass, although cheaper, oxidizes in diesel fuel. Stainless ensures maximum compatibility with all types of fuel. I know what fittings I need from Summit, but haven’t ordered them yet. I think I’m going to use the Aeromotive pump like lmills has for my booster pump, but haven’t ordered that yet either. I intend to wire this system to switches in the cab that will allow me to pump fuel manually with the truck off using either the stock lift pump or the booster pump or both.



Total cost for this system should run around $700 assuming a $200 bargain for the Davco unit. Buying it new would have made it unaffordable for me.



This is my main winter project this year. I will be assembling the components and testing everything over the course of the next several months, then installing it in the spring when the weather gets warm again. Rather than post the entire thing all at once, I decided to start this thread now and add to it as I go along. I have pretty thick skin (I think), so I’m open to criticism and debate about what I’m doing here. Please understand - I am in no way affiliated with any of the companies I discuss here, I just happen to have favorable opinions of them and their products. Also, I am not in any way saying that what I'm building is any better than systems like FASS, Preparator, or Frantz... this system is just what *I've* decided would be best for *my* application. Bottom line: I'm not "putting down" anyone else's fuel delivery system. I've done the research, and this is what I've decided is the best for me. You may decide otherwise.



-Ryan

 

[amsoilman]

Ryan,

Looks to me like you have done a lot of "Homework"! I certainly hope it does you well, as it should! What kind of flow does this monster have?



Wayne

amsoilman

 

[realsquash]

I've been thinking about this whole fuel system. I have a thing against external fuel pumps. Whoever first put the pump in the tank is a genious. Since the 2005 MY supposedly comes with an in-tank pump, I'd be interested to know if that would fit into the 03 or 04 tanks... And I wonder if it's the same style of pump used on EFI gas engines?



There isn't a 2 micron filter that fits the stock canister? Is there anything better than 10 that does?



Andy

 

[mhenon]

rbattelle, This looks like a great project and I'm sure there will be a lot of folks following your progress. One point I'd like to bring up and I don't know how it applies to 3 gen rigs.

The earlier trucks have an in tank fuel screen/filter module. It's a fine mess screen and various intake/return lines all enclosed with-in this plastic type canister. Don't know whats in the 3rd gen trucks but this might be of concern if your fuel system is going to draw a lot of fuel. In other words if you're using 1/2 inch line and sucking up large quanities of fuel and this canister is 1/4 or 3/8" line with some type of check valve at the end, you could be looking at cavitation issues.

Just something to keep in mind as you go foward with this. Keep us up-dated!

 

[rbattelle]

Ryan,

Looks to me like you have done a lot of "Homework"! I certainly hope it does you well, as it should! What kind of flow does this monster have?



Wayne

amsoilman

Thanks, Wayne!! That really means a lot coming from you, as I know how cautious you are about products you'll use. The Davco 382 will flow up to 150 GPH (of course, I won't be anywhere near that, but the Aeromotive booster I'm probably going to get is good to over 150 GPH).



Andy,

In theory, this setup would work fine with your in-tank pump, but it would take a lot more reengineering to also install the booster in the tank. The only filter that will fit in the stock canister is the Fleetguard model it came with... and it's only available in 10 micron rating. The issue is that 2-micron filters need more pressure to push the fluid through all those tiny pores, and the stock lift pump probably isn't enough... so even if a 2-micron could be found to fit in the stock canister, you wouldn't want to do it without adding a booster. In addition, the stock filter is pretty small and might clog up too fast with a 2-micron rating.

 

[realsquash]

What I meant to say was to just ditch the stock lift pump and run an in-tank pump if possible, maybe with the 2-micron filter in series.



Andy

 

[rbattelle]

The earlier trucks have an in tank fuel screen/filter module. It's a fine mess screen and various intake/return lines all enclosed with-in this plastic type canister. Don't know whats in the 3rd gen trucks but this might be of concern if your fuel system is going to draw a lot of fuel. In other words if you're using 1/2 inch line and sucking up large quanities of fuel and this canister is 1/4 or 3/8" line with some type of check valve at the end, you could be looking at cavitation issues.

This is something that never crossed my mind. Except during fuel filter changes (when I'd run the fuel pumps with the engine off in order to prime the system), fuel flow rate will be bone stock since I don't run any kind of performance enhancing fuel box and my engine is basically bone-stock. It is my hope then, that cavitation problems would be conveniently avoided. But I must confess I don't know enough about cavitation to speak intelligently about how much trouble it might be.

 

[JimKing]

"The issue is that 2-micron filters need more pressure to push the fluid through all those tiny pores, and the stock lift pump probably isn't enough...



When switching from the stock 10 micron on the FASS to the 2 Micron NAPA FIL1724 there is a very slight but noticable reduction in pressure. For me it was about 1. 5 psi across the entire range, idle to WOT. Something to consider.

 

[Hohn]

Wow, Ryan! This is something you've obviously invested a great deal of effort into. There's not a whole lot I could add, exept some general comments:



-- Braided SS is nice, but I have "seen the light" and would recommend socketless, push-on, barbed type fittings that still use AN sizing. I have braided on my FP guage and my Max-flow, and I think that the socketless would have worked better. Injection pumps tends to produce a lot of pressure pulse waves that radiate from the inj pump back down the fuel system. The flexibility of the rubber-based hose will help to dampen these pulses and make the system quieter and more durable. It's also a LOT cheaper



The aeroquip page says that the socketless hose has "unsurpassed fluid compatibility". Whatever that means.



http://www.aeroquip.com/pages/prodinfo.html



The 2 micron filtration capability is something that you should truly consider if you really need. While it's nice, it REALLY complicates the install. It also means that you're more likely (a little, anyway) to gel up, and you'll have less fuel flow.



A micron is . 00003937 inches. (see this source) That's pretty small. With 10 micron filtration, you are catching things larger than . 00039 inches. Are there tolerances inside the pump that are smaller than this? Maybe there is a worthwhile value to the 2-micron filtration, but maybe there isn't. This is a key decision as it really affects the design of the rest of your fuel system.



If you want to retain the 2-micron filtration, I'd consider a "bypass" type of setup- like a swimming pool filter. Plumbing in the 2-micron filter in parallel will ensure maximum volume and allow you to start the truck even if the 2-micron filter gels, because you still have the OEM filter/heater working. Over time, the parallel filter will remove most of the small particles, even if it can't prevent them from hitting the pump (because it's not in series).



IMHO, any coolant-based fuel heater setup is utterly worthless. What good does it do on a cold start when the coolant is cold? NONE!



If you need a heater, an electric heating element is really the only way to go.



I'd encourage you to keep as much of the system under the hood as you can. The heat will help prevent gelling, and will protect the components.



I'd also suggest you keep as much of the stock system as possible.



To prevent cavitation, you're probably going to want to install some kind of sump in your tank or tap it for a bottom feed. I don't think the OEM design can accomodate that huge flow requirements of the Aeromotive pumps.



It may be better to stick with a cheaper, smaller Carter as a boost pump if you don't want to mess with modding the tank.



Maybe you could plumb that 2-mircon filter into the fuel return? That would accomplish the parallel bypass setup with less plumbing.



Your setup looks like a good one!



JMHO



Justin

 

[nickleinonen]

A micron is . 00003937 inches. (see this source) That's pretty small. With 10 micron filtration, you are catching things larger than . 00039 inches. Are there tolerances inside the pump that are smaller than this?

in the pump they can get down to that small, but in the injectors they can get even smaller down to 1 micron or so... clean fuel is good fuel... i've been thinking of doing something like this too... i look forward to seeing the results of this...

 

[Tomeygun]

in the pump they can get down to that small, but in the injectors they can get even smaller down to 1 micron or so... clean fuel is good fuel... i've been thinking of doing something like this too... i look forward to seeing the results of this. .

As am I, But darn is that thing huge!!! 16 inches tall and 6 inches around?



where will that possibly fit?

 

[Yo Hoot]

Nice job on the details.



I'm a convert from the Dmax side of things. Already been there done that with 2 micron filtration. You can buy premade kits from at least three different sources for the Dmax... CAT, Baldwin and Racor brands... even with plug and play WIF and heaters.



Yes the filtration is sure to make your fuel system more durable but unfortunately four years of Dmaxes with 2 micron filters and there has not been any significance in the failures of the injectors. It seems the premature injector failures are caused by design, not dirt. Trucks with supplemental filtration fail at what seems to be no different rate than those without.



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[rbattelle]

Hohn- many thanks for your comments. I will definetly take them into consideration as I continue this project. With regard to the Aeromotive pump's high flow capacity, I think I'm just going to plumb it in there and see what happens. I figure worst case it can't draw enough fuel through the existing tank lines and it'll fry itself. Time will tell. I agree that a coolant heater is absolutely useless, I was just commenting that this Davco model has one. It also has an electric heater.



Yo Hoot, your experience with the DMax is valuable, and I'm discouraged to hear that the failure rates seem to be no different between trucks with 2-micron filters and those without. But knowing my fuel is filtered to 2-micron will make me feel better (I guess).



Tomeygun- I have test-fit the Davco and I believe it can be conveniently mounted right above the injection pump, bolted to the engine block. I'm in the process of re-assembling the filter after having cleaned it all up and this weekend I'll try fitting it again and take some pictures. It's a tight fit... to the point that engine vibrations must be accounted for to prevent the filter striking the underside of the hood!!



I think I'm going to make a major change to my plumbing design. I'm now seriously considering eliminating the stock lift pump. I bought a plate from Scotty (www.scottyairsystems.com) that fits in place of the stock LP and provides a 3/8 NPT fitting. Doing this would eliminate several fittings and connections, thereby simplifying the overall system (my philosophy is that simpler is usually better - I'm aware of the irony of having this philosophy and yet still doing a project like this). I figure running just 1 lift pump (Aeromotive or perhaps a Carter as Hohn suggests) back near the tank will make adjusting the system easier, but it makes for a single-point-of-failure setup.



I've also decided that I need to run a regulator with that Aeromotive pump. I'll plumb the return line into the factory return line.



I've drawn up a preliminary electrical system. Plan is to use 2 boxes: one in the engine compartment to house the pump relay(s) and one in the cab to house a fuel pressure gauge, pump switches, and some LED's that indicate when the pump(s) are running.



Sometime in the next several days I'll update my plumbing diagrams and post the new ones here. I continue to wait on my Swagelok fittings, and have not ordered a pump or any of the AN fittings I need, as some details are still being worked out.



I'd like to hear some other opinions on whether the Aeromotive pump is "too much" for the stock fuel connections at the tank. Bear in mind I have no aftermarket fuel-enhancing devices, so flow rate to my engine will be unchanged. I know lmills is running the Aeromotive pump (P/N AEI-11203 at Summit) I'm looking at and I believe he's had good experience with it.



-Ryan

 

[rbattelle]

Also, that Aeroquip socketless hose looks interesting. How easy is it to remove the hose from the barb once it's installed?

 

[JHardwick]

gotta put some bull's cum (ivory liquid and murphys oil soap mixture) on it to get it on, and slit it to get it off, lol



i've plumbed up my share of race cars with the stuff!!

 

[JHardwick]

gotta put some bull's cum (ivory liquid and murphys oil soap mixture) on it to get it on, and slit it to get it off, lol



i've plumbed up my share of race cars with the stuff!!

oh, dipping the end to be pushed on in boiling water for a sec helps too :-laf



can you say ... ... ... . cold garage, two hands, full body weight against a post?



WD40 will not work before anybody responds. I've tried it and it's a BIATCH!!

 

[rbattelle]

oh, dipping the end to be pushed on in boiling water for a sec helps too :-laf



can you say ... ... ... . cold garage, two hands, full body weight against a post?



WD40 will not work before anybody responds. I've tried it and it's a BIATCH!!

Wow, sounds like a real PITA. I guess I'll probably stick with braided stainless, then. Although I find that a PITA to assemble sometimes too.

 

[JHardwick]

Wow, sounds like a real PITA. I guess I'll probably stick with braided stainless, then. Although I find that a PITA to assemble sometimes too.

Actually, what I was trying to say was it can be a real pain if you don't do it proper ie cold weather, WD40 etc



But, if you warm the hose a bit and use bull's cum, it'll slide right on. You can never get it back off without destructing it though.

 

[willyslover]

rbattelle. . might I suggest you contact CSutton. . Chris has more time on his Aeromotive pump system than any on this board. . [that I aware of]

he has had some failures in the several years he has used it and can tell you where and what to look out for... . I'll send him a E mail and link this thread, maybe he will respond what he has had troubles with.

 

[LightmanE300]

Rbatelle - well you certainly dove deep into this one!! LOL that first post is a novel! I couldn't bear to read the entire thread, however I have some experience in the area, and similar concerns as you do. I noticed you didn't check out Stanadyne's filters, they make some nice units.



On my 02 TDI, I plumbed a 2 micron absolute filter in line after my stock fuel filter, as a 'final' or polishing filter. I did experience a pressure drop, and when towing and flooring it (I was chipped) I could draw it down to a vacuum to the point my car would stall out. The filter was small though and the flow rate was less than fantastic. I don't see why you wouldn't just plumb in a 2 mic filter in line , add a pusher pump, and be done with it. . ? No offense but it seems to me that you've way overcomplicated the issue.



OH PS, I ran b100 for 35k miles straight through the stanadyne FM100 with no problems.