Ford's answers to the NHTSA 6.7 Investigation

[ricatic]

There was a request for a link to Ford's answer's to the NHTSA investigation posted on a previous thread, since closed. Here is the link:

Ford's NHTSA Answers to the 6.7 investigation

This PDF is over 20 pages long. There are some interesting statements contained in the documents. My favorite is the one where Ford says they buy the pump from Bosch as a "black box" and do no testing of the component. It is closely followed by the tantamount admission that the pump will not provide a long service life when exposed to the poor lubricity fuel found in the US. You will have to do the math using the sales versus failure tables for the US and Canadian trucks. Eye opening difference to say the least...

Regards

[Huntindog]

Even though I have a GM, and they are honoring the warranty now, and IMO will continue as they should be seeing the fiasco that Ford has gotten themselves into.....I am interested as I tend to keep my trucks long after the warranty is up. I currently have about 64 months and 85,000 miles left on the warranty, and thus that much time for this situation to get figured out.

I am not using any additives. I never have believed in them. GM discourages them. The additive that Ford pushes was NOT (according to a ford tech) tested with the 6.7....Ford tested it in the past on their previous diesels. Since Ford states that they don't know anything about the CP-4 pump...They buy it as a "black box" from Bosch.(NHSTA response) Then I cannot see where they have any way of knowing if their PM22A is helping or hurting their HPFP...The only thing they can be certain of is that the PM22A sales are helping the bottom line.

So I figure that when /if the time comes that the solution is found that I will use the money saved on additives to put towards the "fix".

This could include a premptive pump changeout if necessary. Lots cheaper to change just a pump, and I would do it IF I knew that it would last.

[NewsW]

Trail-Mate wrote:
Sounds alot like the old issue of the lift pump not supplying enough pressure and fuel to the High Pressure Pump, just like the older Dodges did when the had that Carter Lift Pump that would fail or drop pressure then take out the High Pressure Pump.

That is in my folder as "cavitation", running dry, hydroshock (when it primes again), etc.


Just doing failure analysis homework by laying out all possible ideas and avenues.. then pursuing them one by one.

[Trail-Mate]

Based on this comment. Two Detroit Diesel engineers have inspected the HFPP from my truck. No water, no sign of particle contaminants...just an under lubricated and overheated pump assembly.

Makes me wonder what pressures and line sizes are used in the GM and Ford trucks from the tank to the High Pressure pump. Sounds alot like the old issue of the lift pump not supplying enough pressure and fuel to the High Pressure Pump, just like the older Dodges did when the had that Carter Lift Pump that would fail or drop pressure then take out the High Pressure Pump.

[ricatic]

Artemus Gordon wrote:
This is making me ill. Does anyone smell "dead Horse"! :Z

I must ask why are you bothering to waste your time here...no dog in the fight unless you have a truck other than the one in your signature...and by admission you are bored...opening a particular thread requires a specific action on a readers part...ignore what does not interest you...

Page 27...few posts like this one...I would say interest is high

Regards

[NewsW]

Rick --- this is a key paper:

----------

The 2000bar common rail system for passenger cars and light duty applications
Authors: Fein, O.M.1 ; Gordon, U.1 ; Projahn, U.1
Author affiliation:
1 Robert Bosch, Diesel Systems, System Development, Germany
Corresponding author: Fein, O. M.
Source title: Institution of Mechanical Engineers - Injection Systems for IC Engines
Abbreviated source title: Inst. Mech. Eng. - Inject. Syst. IC Engines
Monograph title: Institution of Mechanical Engineers - Injection Systems for IC Engines
Issue date: 2009
Publication year: 2009
Pages: 99-110
Language: English
ISBN-13: 9781843345619
Document type: Conference article (CA)
Conference name: Injection Systems for IC Engines
Conference date: May 13, 2009 - May 14, 2009
Conference location: Westminster, London, United kingdom
Conference code: 80279
Publisher: Chandos Publishing, Avenue 4, Station Lane, Witney, Oxford, OX28 4BN, United Kingdom



Abstract: In 2007, Bosch introduced a 2000 bar common rail system into the market. Due to its piezo technology highly flexible injection patterns can be realized. At the same time the precision of fuel metering is also increased. This paper summarizes the overall system: Components are outlined, which contribute most in terms of improving hydraulic efficiency and fuel consumption. Furthermore, system functions are addressed which play a part in exact fuel metering, also in the context of stability over life-time. Conclusively, it is illustrated which important role this fuel injection system plays in state-of-the-art engine concepts. © Robert Bosch, 2009.

[Artemus_Gordon]

This is making me ill. Does anyone smell "dead Horse"! :Z

[NewsW]

Could there be a hydrostatic phenomena there as the pump and the injectors set up standing waves at certain frequencies / rpms?

--------------

An experimental study on the rail pressure fluctuation characteristics of high-pressure common rail fuel system
Authors: Liu, Xinghua1 ; Fan, Zhiqiang1 ; Gao, Zhuo1
Author affiliation:
1 School of Mechanical and Vehicle Engineering, Beijing Institute of Technology, Beijing 100081, China
Corresponding author: Liu, X.
Source title: Qiche Gongcheng/Automotive Engineering
Abbreviated source title: Qiche Gongcheng
Volume: 32
Issue: 7
Issue date: July 2010
Publication year: 2010
Pages: 575-578
Language: Chinese
ISSN: 1000680X
CODEN: QIGOE4
Document type: Journal article (JA)
Publisher: Society of Automotive Engineers of China (SAE-China), Room 1202, No.1 Baiyunlu, Xicheng District, Beijing, 100045, China


Abstract: By experimental measurement and using fast Fourier transform, the frequency characteristics of rail pressure fluctuation of high-pressure common rail fuel system BOSCH CR under different load conditions are investigated. The results show that with the increase in engine load, the amplitude at the triple frequency of fuel pump rotation frequency increases and will be dominant among all frequency components caused by fuel supply; when load is low, the fuel delivery in each of 3 plungers is slightly different to each other; but when the load goes up, the fuel delivery in 3 plungers tends to be the same.

[NewsW]

What about how do they monitor for pump durability?

-----------------

Research and implementation of monitoring system for injection pump durability tester

Authors: Xiao, Chun1 ; Ming, Li1 ; Shan, Hu1 ; Zhang, Lijun1
Author affiliation:
1 Wuhan University of Technology, Wuhan 430070, China
Corresponding author: Xiao, C. (xiaochun70@163.com)
Source title: Procedia Engineering
Abbreviated source title: Procedia Eng.
Volume: 15
Monograph title: 2011 International Conference on Advanced in Control Engineering and Information Science, CEIS 2011
Issue date: 2011
Publication year: 2011
Pages: 1061-1065
Language: English
ISSN: 18777058
Document type: Conference article (CA)
Conference name: 2011 International Conference on Advanced in Control Engineering and Information Science, CEIS 2011
Conference date: August 18, 2011 - August 19, 2011
Conference location: Dali, Yunnam, China
Conference code: 87786
Publisher: Elsevier Ltd, Langford Lane, Kidlington, Oxford, OX5 1GB, United Kingdom



Abstract: Taking the background of the durability test for high-pressure common rail injection pump which is made in the Bosch firm, we have designed the monitoring system of injection pump durability tester based on fieldbus control system (FCS) [1], [2]. Firstly, the paper total analyses the injection pump durability test. Then it mainly introduces the hardware of the monitoring system and puts forward configuration of the test. Finally we completed the software of the monitoring system based on the platform of Lab Windows/CVI. It improves the working efficiency greatly of the tester. © 2011 Published by Elsevier Ltd.

[ricatic]

1jeep wrote:
Wow 26 pages and still going...who is running this thread the enegizer bunny?

Civil discussion supported by known facts driving honest guy's who want to know why Ford has taken the low road when it comes to customer service regarding Bosch CP4 series HPFP's.

There has been a goodly amount of excellent information discussed on this thread...despite occasional attempts by some to get the thread closed.

According to answers provided to the NHTSA by Ford and GM, percentage wise, Bosch CP4 series HPFP's are failing at very similar rates. It is not about filtration. It is about lubricity...or a breakdown of the hardening coatings on the internal parts. Two Detroit Diesel engineers have inspected the HFPP from my truck. No water, no sign of particle contaminants...just an under lubricated and overheated pump assembly.

Regards

[NewsW]

Or Particle Contamination?

Note this article is out in 2009, well after the CP 4 design is frozen.

Real eye opener --- filtration standards not good enough because of vibration of filter, viscosity, need better standard.

Also note where the authors are from...

----------------

Procedure for determining the allowable particle contamination for diesel fuel injection equipment (FIE)


Authors: von Stockhausen, Alexander1 ; Mangold, Martin P.1 ; Eppinger, Dieter1 ; Livingston, Thomas C.2
Author affiliation:
1 Robert Bosch GmbH, Germany
2 Robert Bosch LLC, Germany
Corresponding author: von Stockhausen, A.
Source title: SAE International Journal of Fuels and Lubricants
Abbreviated source title: SAE Int. J. Fuels Lubr.
Volume: 2
Issue: 1
Issue date: 2009
Publication year: 2009
Pages: 294-304
Language: English
ISSN: 19463952
E-ISSN: 19463960
Document type: Journal article (JA)
Publisher: SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, United States


Abstract: Increasing injection pressures together with Diesel fuel lubricated Common Rail pumps replacing oil lubricated systems demand a more sophisticated investigation of robustness and durability against particle contamination of fuel. The established way of requiring filtration efficiency levels per lab standard is not significant enough if we look at variable factors like vibration of the fuel filter and viscosity of the fuel. Because these and other factors tremendously influence filtration efficiency, future Diesel FIE cleanliness requirements will need to define an allowable contamination limit downstream of the filter. More precisely, this is not a scalar limit but a contamination collective that considers the varying vehicle filtration and operating environment. This paper describes a procedure for defining allowable contamination limits of the FIE components. The procedure includes sensitivity, robustness and "key life" tests. The latter one is similar to a S-N curve (Woehler curve) and is the basis for the damage accumulation model of particle contamination. © 2009 SAE International.

[NewsW]

Is lubricity the issue?

The gorilla in the room..

Tribological investigations is not done at 2,000bars / 100-150C operating temp of the pump.

Note the authors... another 2009 study... after CP 4 is out.


--------------------

Diesel lubricity requirements of future fuel injection equipment

Authors: Matzke, Markus1 ; Litzow, Ulrike1 ; Jess, Andreas2 ; Caprotti, Rinaldo3 ; Balfour, Graham3
Author affiliation:
1 Robert Bosch GmbH, Germany
2 University of Bayreuth, Germany
3 Infineum UK, United Kingdom
Corresponding author: Matzke, M.
Source title: SAE International Journal of Fuels and Lubricants
Abbreviated source title: SAE Int. J. Fuels Lubr.
Volume: 2
Issue: 1
Issue date: 2009
Publication year: 2009
Pages: 273-286
Language: English
ISSN: 19463952
E-ISSN: 19463960
Document type: Journal article (JA)
Publisher: SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, United States



Abstract: This paper looks at the underlying fundamentals of diesel fuel system lubrication for the highly-loaded contacts found in fuel injection equipment like highpressure pumps. These types of contacts are already occurring in modern systems and their severity is likely to increase in future applications due to the requirement for increased fuel pressure. The aim of the work was to characterise the tribological behavior of these contacts when lubricated with diesel fuel and diesel fuel treated with lubricity additives and model nitrogen and sulphur compounds of different chemical composition. It is essential to understand the role of diesel fuel and of lubricity additives to ensure that future, more severely-loaded systems, will be free of any wear problem in the field. The lubricity with the High-Frequency Reciprocating Rig (HFRR) and the critical load of incipient scuffing (loadcarrying capacity) in the High-Temperature Oscillating Machine (HiTOM) using real components of a Common Rail (CR) pump as test samples depends on the composition of the base fuels. A content of 5 % rapeseed-methyl ester (RME) in fuel increases the loadcarrying capacity and increases the lubricity. Hydrodesulphurization decreases the lubricity of gas oil by 80 - 200 ?m and the load-carrying capacity by 1500 N. Model sulphur compounds benzothiophene, dibenzothiophene and 4,6-dimethyldibenzothiophene cannot restore the lubricity of a hydrotreated diesel fuel, but can increase the load-carrying capacity. The model nitrogen compound 8-hydroxyquinoline improves the lubricity at very low concentrations (20 ppm nitrogen) whereas quinoline and acridine need a higher concentration (100 ppm nitrogen) for some lubricity improvement. The outcome of this work has confirmed that specific lubricity additive chemistries can stretch the mixed lubrication area where highly-loaded contacts can operate safely. Specific lubricity additives with carboxylic acid-, ester- and amide based chemistries can increase the lubricity in a variety of base fuels at a concentration of 200 ppm to meet the lubricity requirement according to EN 590. These compounds can provide protection against adhesive wear by increasing the incipient scuffing load. Higher than market-typical additive concentrations can further increase lubricity, but are levelling at concentrations between 1000 ppm and 2000 ppm. The ester-based additives level at a lower value than the acid and amide based additives and so can provide further protection to FIEs. The load-carrying capacity of test fuel - ULSD 1 - can be increased by 4500 N by an ester content of 1000 ppm. The acid can only provide an increase of 2500 N. The ester-based additive at 200 ppm can already provide an improvement of the load-carrying capacity by 3000 N at a fuel temperature of 90 °C. Tribological investigations with the HiTOM showed an excellent correlation between the results of this test and the HFRR results. © 2009 SAE International.

[NewsW]

durallymax wrote:

still on the passenger side valvecover, before pump. It would take a hell of a filter to hold up to that much PSI.

There should be a final strainer before the fuel enters the injector.

Don't know if it is at the common rail or in front of injector.

The strainer is usually metal.

If I were doing the fuel intake / strainer design, there would be a way for particles to be flushed back toward the fuel tank as it exits for recirculation.

[Engineer9860]

1jeep wrote:
Wow 26 pages and still going...who is running this thread the enegizer bunny?

Check your forum settings. I only have 13 pages.

[durallymax]

hoopers wrote:

NewsW wrote:
Now we find out about filtration:

Filtration Technology Challenges for Common-Rail Diesel Engine Fuel Systems
Number: 2009-01-0874

Published: 2009-04-20


Publisher: SAE International

Language: English
DOI: 10.4271/2009-01-0874
Author(s): Christopher J. Salvador - Caterpillar Inc.
Citation:
Salvador, C., "Filtration Technology Challenges for Common-Rail Diesel Engine Fuel Systems," SAE Technical Paper 2009-01-0874, 2009, doi:10.4271/2009-01-0874.


Citation

Abstract:

The focus of this study was to determine the role of liquid filtration in controlling debris in fuel and maintaining common-rail fuel system life for off-highway diesel engine applications. Three key areas of filtration design surfaced as most important areas of focus – basic filtration efficiency, robustness of filter manufacturing, and filter assembly cleanliness from production (before and during installation into fuel system). The study also revealed the importance of designing fuel filtration systems consisting of primary filtration (suction-side water separation and particulate filtration) combined with pressure-side particulate filtration. The performance characteristics of the filtration system as a whole were found to be extremely critical in optimum fuel system performance and life goals, especially in severe-duty applications.

The study analyzed two filter systems – the Control System that consisted of pre-common-rail technology and the Proposed System that included all of the improvements designed to adequately protect the fuel system. The Control System consisted of B 20(c) = 75 primary filtration and B 8(c) = 75 secondary filtration. The results of the study recommended the Proposed System consist of B 10(c) = 75 primary filtration and B 4(c) = 200 secondary filtration. This system improved fuel system life by 20× in normal applications and nearly 10× in heavy-duty applications.

Several test methods were used to generate data including the multipass test (ISO 4548-12), fabrication integrity ( ISO 2942 ) test, and specially developed production cleanliness and fuel system simulation tests. The study examined the adequacy of existing filtration technology in protecting common-rail fuel systems (benchmarking) and determined acceptable design requirements in the previously mentioned areas for individual fuel filters (pressure-side filtration) and filter systems (combining suction-side and pressure-side filtration).

From what I have read, GM filters down to a smaller particle level than Ford (no idea about VW filtration). I don't completely understand where the filter is located, but I would guess it is before the pump, thus filtration should play an important role in pump protection...this seems obvious to me.

Is lubricity the culprit? How does filtered particle size affect lubricity?

I have seen no statements or data proving lubricity is the culprit. Just supposition and assumptions, really. I am not saying its not lubricity, just that it could be something else, and lubricity is a red herring at this point. The fact Canadian fuel meets the ASTM specs, and yet there are failures? This is a glaring exception that makes me question the lubricity spec and how it might play into the pump failures.

This makes me think ASTM lubricity might play a minor role, and there is a larger factor out there. But that is just my thoughts....

As to people claiming the failure rates are similar between GM and Ford (and what about VW?), I would question how accurate this data really is? Is EVERY pump failure included in the sample lots? What is the nature of the pump failures included in these samples...are they the same?

I did call a couple duramax dealers today regarding adding diesel additives on my 2011 duramax. One dealer seemed to understand my concern and said GM does not support ANY additives. Though he did say customers are adding it, but again, the official position is NO additive. My 2011 owners manual makes no mention of any supported additive, except to consult your local dealer.
The other dealer seemed to be confused on the subject and really didn't have any advice except one doesn't really need additives.
However, the GM first dealer said my 100000 mile warranty would cover any fuel pump issues, so for me, I might just go with standard fuel, and if I am one of the unlucky ones, I will just count on GM fixing my fuel pump. I doubt I will keep my truck past 100000 miles.

still on the passenger side valvecover, before pump. It would take a hell of a filter to hold up to that much PSI.

[mapguy]

NewsW wrote:
Now we find out about filtration:

Filtration Technology Challenges for Common-Rail Diesel Engine Fuel Systems
Number: 2009-01-0874

Published: 2009-04-20


Publisher: SAE International

Language: English
DOI: 10.4271/2009-01-0874
Author(s): Christopher J. Salvador - Caterpillar Inc.
Citation:
Salvador, C., "Filtration Technology Challenges for Common-Rail Diesel Engine Fuel Systems," SAE Technical Paper 2009-01-0874, 2009, doi:10.4271/2009-01-0874.


Citation

Abstract:

The focus of this study was to determine the role of liquid filtration in controlling debris in fuel and maintaining common-rail fuel system life for off-highway diesel engine applications. Three key areas of filtration design surfaced as most important areas of focus – basic filtration efficiency, robustness of filter manufacturing, and filter assembly cleanliness from production (before and during installation into fuel system). The study also revealed the importance of designing fuel filtration systems consisting of primary filtration (suction-side water separation and particulate filtration) combined with pressure-side particulate filtration. The performance characteristics of the filtration system as a whole were found to be extremely critical in optimum fuel system performance and life goals, especially in severe-duty applications.

The study analyzed two filter systems – the Control System that consisted of pre-common-rail technology and the Proposed System that included all of the improvements designed to adequately protect the fuel system. The Control System consisted of B 20(c) = 75 primary filtration and B 8(c) = 75 secondary filtration. The results of the study recommended the Proposed System consist of B 10(c) = 75 primary filtration and B 4(c) = 200 secondary filtration. This system improved fuel system life by 20× in normal applications and nearly 10× in heavy-duty applications.

Several test methods were used to generate data including the multipass test (ISO 4548-12), fabrication integrity ( ISO 2942 ) test, and specially developed production cleanliness and fuel system simulation tests. The study examined the adequacy of existing filtration technology in protecting common-rail fuel systems (benchmarking) and determined acceptable design requirements in the previously mentioned areas for individual fuel filters (pressure-side filtration) and filter systems (combining suction-side and pressure-side filtration).

Filtration and water control is a place where all three OEM diesel pickup manufacturers can improve their product.

GM is using a 4 micron nominal filter with an aquablock media. But Bosch's research along with Cat's studies determined that pump and injector life was compromised with particles that can be "missed" by the OEM filtration.