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Burner,
A bypass doesn't apply to a fuel filter system since the fuel only takes a single pass through the filter before being consumed. A bypass works for oil because the oil is constantly being re-circulated through the filter(s).
John K,
If it turns out that there is not a practical way to add a better filter after the OEM primary filter, would it be acceptable (though not ideal) to put a "better" filter in front of the OEM filter?
[ 11-06-2002: Message edited by: jbplock ]</p>
George, JK
Is the efficiency rating of ~60% for the samples that were taken directly after the filter? From a previous post here George had said the following:
"Also, the sample point for the 'after filter' was the return line to the fuel tank. This then is after the fuel has made its complete trip through the filter, pump, injector circuit, and injectors. Thus, if we have a component producing wear particles, a failing component, carbon, etc. anywhere along the route, our particle count for this sample would reveal that debris also. This may be the source for the large particles and may well increase the particle counts.
We have additional 'before & after' samples that should be completed next week which are using a different sample point for the 'after', that being immediately after the filter, pump, but before the injector circuit. "
Have the results from the tests where the sample is taken directly after the filter come back yet? If the 60% efficiency rating is for fuel that's getting recirculated back to the tank, why is that so bad? If the efficiency for the fuel actually getting to the injectors is much higher (> 94%) then it should still be quite good, no?
Yes, the results for "after filter only" are complete and the results are consistent with our previous results, at 62% efficiency for greater than 5 micron particle size. The 2 to 5 micron size spectrum was only 44% efficient... More results this week but I think we have our answer at 60% to 64% efficient in the 5 micron component, the size most affecting our fuel system life.
George Morrison, STLE CLS
Comment on water separation
I changed my first filter at 12000 miles when I opened the filter drain cock for the first time only 2 drops of water came out (I assumed no water in the fuel I have been buying).
I cut the fuel canister in two and observed that only the bottom 1/2 was a discolored black and the top half was a discolored white, not what I had expected.
So I have to ask this question????? has my fuel filter been on BYPASS the whole time, but I just read there isnt a bypass so why is the filter so clean and no water?????????
Any response would be welcomed.
[ 11-06-2002: Message edited by: letsgo ]
[ 11-06-2002: Message edited by: letsgo ]</p>
George,
I add my thanks for all the work you are doing on this issue. If you need additional samples let me know and I'll forward one from my truck too.
Regards,
bob
letsgo,
What you saw is completely normal, as I have observed it in every fuel filter life test that I ever conducted. The fuel flow almost always starts at the bottom of the filter(depends on design) and works its way up as the media gets contaminated. The white was just the unused portion of the filter. If you noticed when you changed the filter there was a tube that went quite a ways into the center of the filter, its near the bottom of the media when installed and causes the suction pressure to be centered around there at the beginning of life. Had you ran the filter longer the media would have been used and coated entirely as you expected to find. Mine was around 3/4 used when I changed at 13k.
George,
Any ideas on what kind of filter set-up might fix our problem? The Stanadyne FM-100 is looking very promising to me.
I've got to add something else here before the lynch mob lights the torches and shows up on Racor's door.
The 95% efficiency numbers are obtained using fuel conforming to ISO/TR 13353, the ISO test for fuel filter particle retention and efficiency. This fuel is dosed with a much larger percentage of contaminant than you will ever see out of the pump, it looks black when totally mixed. This is done first to speed up the test so it doesn't take a month to perform, second it levels the playing field so everyones results can be compared at a predetermined contaminant level(George I assume will agree that initial contaminant level in fuels will vary widely depending on location), and third sets the contaminant at a level we should never see(makes the test harsher on filter).
With that said, as contaminant levels drop, your effective efficiency at removing them will fall accordingly.
Todd,
Did you find a spec on the Stanadyne FM-100's flow resistance (in inHg)? They quote a flow rate of 80 GPH but I didn't see a spec for flow resistance on their web site. Sent them an email request a few days ago but haven't heard back yet. It does look like a nice filter ( if the specs are as good as they claim).
jbplock
No I don't, but as George stated earlier tha our pump has a 60hg and the oem filter takes 8 of that. Therefore it will handle one more filter. Besides if it doesn't and it will, stanadyne makes one with a lift pump on it.
jbplock
Tech support at Stanadyne told it would be 2 inhg and 1psi on a new filter. Looking better all the time. The whole unit only cost $90 and that is with the head, element, hand primer and plastic bowl.
Thanks Todd.. Yes remember reading George's post on our pumps 60inHg rating and you're right that it should easily handle the load from the added filter. It just would be nice to know the Stanadyne spec. I just read one of the data sheets on the Standyne website and it states that the flow resistance spec is available upon request. If I get a response I'll post it. Being a chronic worrier, I 'm concerned that if I ever had a pump problem the dealer could claim that it was due to the added load of the extra filter... just be nice to have some back-up data in that case.
[ 11-06-2002: Message edited by: jbplock ]</p>
jbplock
Read my last post. I was posting the same time you were.
We have to assume that Bosch, Dmax, and GM designed these fuel systems to operate in the real world. Certainly, the cleaner the fuel the better, but there comes a point at which "good enough" is really good enough.
What I can't seem to locate in this thread is any data that equates a certain fuel cleanliness level to a certain number of miles or hours of operation, with comparisons between different levels of fuel quality.
What most people want to know is, what is the typical fuel system life with OEM filters, and what would it be with better filtration? Good data and proven results - in the real world...
MP
MorePower,
What I see is that there is proof that dirty fuel causes all kinds of problems in the new modern day high pressure injection systems. You can look around on the internet and see that. George quoted CAT's study of just that. I think if we wait till we have our own proof of this it will too late. I personnally don't have $5K or $6K laying around to buy injectors and/or a pump, when I can buy a $90 filter that will most likely eliminate the problem. As you can see adding another filter won't hurt. I went by my dealership today and ask the service manager if he would void my warrenty if I added another filter and he said most definately not. I have a great Service Manager, he's been a friend for at least 20 years.
I'm taking a middle ground here. The power of the internet is a great resource, BUT those poor filter guys must be really "dissing" it for all the calls/tech inquiries that they are getting from all of the people going off in ten different directions. :rolleyes:
As to data and proof, I am a simple man. I feel I am a pretty good judge of what works and what doesn't AND I know who to believe and not. Simply put if the post filter fuel is dirty enough (according to George) to harm hydraulic systems of a LESSER psi, with a better lubricating fluid, then it is obvious to me that this level of contamination is not good for our fuel systems. No need to beat me over the head get me to acknowledge this.
Sure GM and Bosch looked at what was required for filtration, spec'd it etc, but what happened when the bean counters said the price was too much? Did engineering have their sights set on 500,000 miles or 100,000.1 miles? These guys ARE in the parts business too!
It is obvious to me that we will benefit from improved filtration, but again, I'm not rushing into this...
John,
I respect your knowledge on all these subjects and I am not sure why you not "rushing into it".
If the answer to cleaner fuel is adding another filter , then why not go ahead and add one. Post OE or pre-OE? The fuel still gets filtered. Only thing is you might have to change one of the filters more often than the other one.
Hi everyone new to the Forum. I have been lurking for a long time but decided this was a good topic to start adding my $0.02.
Just a thought but if the Fuel/Water Seperator is not removing the water from the fuel then why not unhook the sensor go have an adapter machined to fit in place of the stock filter and have the other side made to match a CAT Spin on Filter or the Filter of your choice.
There is plenty of room for a larger diamter and longer filter. More filtering area. Not to mention the fact that if the filter was a little longer it would be much easier to get a strap wrench on the filter.
Any opinions good or bad are welcome.
Danny
Choreboy I agree,
I just don't know how to do that.
More Power I have to agree with you to a point about GM and Duramax doing their home work on filtration. But even as much as I love my GM vehilces I know that things always have room for improvment and what comes with them is not always the best solution. They are just wanting to get throught the warranty period so they gamble on what it will take to do that and hope for the best.
I worked at Navistar for over 10 years and I can tell you that what they know does not always get applied. I can see this even now with a large account that I have thats building generator sets. What is needed to do the job right is far from what they want to do because as JK mentioned it all comes down to the dollar.
I have had the Racor 2 micron on the 6.5TD for awhile now and it always gets fueled up at the same station. We have a known quality of fuel and we know what the filter did new. I will be doing another after filter sample soon. This might shed some light on how long the R45S element will last.
We were looking at a Dmax a couple of days ago to see just where to put the extra filter. There is plenty of room just ahead of the fuel cooler. We are going to try and come upp with a bracket that will clamp onto the frame so holes do not need to be drilled. Their is plenty of room to put on the 660 or 690.
Greg
I agree with Greg and it is a great location. There is already two holes in the frame you can mount a self made bracket to. Just pick your filter brand as I am most likely going with Stanadyne FM-100. Cost and predicted performance.
Todd
Where did you see the holes? What I am in the process of is a bracket that will hook over the frame and then clamp to the frame. Making it out of 10ga so it will be strong. This way it will be a very simple no hole drilling deal.
Greg
Choreboy,
Welcome to the forum! Talk about picking a ho-hum topic to introduce yourself! J/K :D Congrats on the truck and let us know if you get pics posted up for us to see.
IRT your idea for the add-on filter with the adapter, I don't think it's gonna work. The OEM fuel filter IS the water separator, not a separate unit. The water is supposed to collect in the bottom, set off the sensor if it reaches a certain level (which no one has ever seen this WIF alarm go off) and has the drain plug at the bottom. All of this is in the base of the filter. If you add another filter to the bottom of that one, the fuel will take the path of least resistance, probably the stock filter media. The only way to improve it is to add another filter in line.
WOW!
So far, lots of great info! As most of you know, based on other peoples' research, I think that air bubbles and entrained air in the fuel is also a concern both from a performance and pump/injector life standpoint.
I gotta agree with JK and others, the engineers probably would like to do the ultimate setup, but the bean counters control the bottom line and we get the result of that. I wouldn't have spent $4,000 on upgrades if they did it the way I wanted it the first time around. ;)
To me, the ultimate fuel system upgrade would consist of the following:
1. Drop the tank and clean it of debris; investigate/upgrade the fuel pickup and screen to ensure there are no leaks and it won't get clogged far from home.
2. Disconnect the first fitting at the outlet of the tank and install a hose with hose clamp leading to the first, "coarse" filter mounted by the fuel tank.
3. Install another clamped hose to feed the prefiltered fuel to a pusher pump capable of handling diesel fuel for 100,000mi and supplying 5-10psi at 10gph. The outlet of this pump would have the quick connect male fitting, to which the factory fuel line (originally connected to the tank outlet)would attach. This would pressurize the line from that point on and provide the correct conditions for the factory fittings.
4. Replace the factory fuel filter with something with more fitration effectiveness and flow rate, as discovered by actual test results. I'd expect to replace the coarse filter every 15-20,000mi and the fine filter every 20-30,000mi unless a bad batch of fuel had a lot of contaminants in it.
This would provide the following benefits:
1. Elimination of air bubbles from leaks in the fuel system and entrained air coming out of suspension from too much suction/restriction on a partially clogged fuel fitler. I'm *theorizing* that this would give better, more consistent performance and fuel mileage as well as marginally longer pump/injector life. For more info on the effects of air bubbles and entrained air on a slightly lower pressure HEUI fuel system, check out www.texastowncar.com. They had injectors failing within 10,000-20,000mi of simulated use!
2. 2 stages of filtration to give longer change intervals and more effective fitration. This would hopefully give longer pump and injector life. This I'm sure drastically affects pump and injector life. As expensive as these pumps and injectors are, I don't want to pay for any until well past 200,000mi.
3. An electric pusher pump can reprime the system after a filter change and keep it primed, even in sudden weather changes that I beleive are causing the sudden rash of trucks dying or running weird.
4. This would help eliminate the dreaded "limp mode when the fuel filter clogs". I think this is very unsafe, especially when towing up a hill. To suddenly lose 80% power and have the TC unlock with no prior warning when you need it most is unacceptable.
Here's some more info from the only person I'm aware of to go more than 483,000mi on a Dmax without replacing injectors or a pump, BROKERS.
Quote: "We use a Racor 2 Micron fuel filter after the factory fuel filter,on all our trucks.
We buy fuel like all haulers,when ever we need it.
We have a 100gal bed tanks on all our trucks and it has a Racor fuel fiter and water seperator on it also.We always fuel the big tank since it handles the large nozles at truck stops.The aux-tank feeds the stock tank.
There is no black magic,just keep it clean !"
Questions:
What filter would be best for the coarse filter?
What filter would be best for the fine filter? I'll have to ask BROKER about his setup.
What would be a good recommendation for a pusher pump?
I'm all ears, just watching to see what turns out to be the best.
Regards, Steve
Steve,
I think what Choreboy was talking about doing was having some type of adapter made that allows you to connect the filter head/primer to a better filter. In other words remove the OEM filter, replace with adapter, then screw on the better filter to the adapter. At least thats how I interpeted it. It's an interesting idea, does anyone know why it wouldn't work?
SWLA,
Oh, I see what you're saying. I thought he meant unscrew the water sensor assy from the bottom and add another filter to the bottom of the stock filter.
It would be cheapest to find a better filter for the factory mount. If not avail., then I'd remove the entire factory mount and install another. I haven't looked at how that's mounted...
Regards, Steve
[ 11-07-2002: Message edited by: SoCalDMAX ]</p>
SWLA,
You are correct about my idea. Since the water separator does not seem to separate water from the fuel I thought maybe I can fool the computer into thinking everything is OK and put another type of fiter in the system. The water separator only has two wires which leads me to believe that I can either leave it unpluged or short it out and the system would not know the differance. Then I could put a CAT filter in the system by means of an adapter. I am looking into having an adapter made by a machine shop by using an old OEM filter and a CAT filter. I will also have to look into whether or not a CAT filter will be too much of a pressure drop on the fuel system which leads to SoCalDMax's observation.
SoCalDMax,
If I was to add a pressure pump after the tank will it effect the already existing pump that pulls a vaccum from the tank. Does any major filter Manufacturer make a Pump, Filter, and Water Separator in one unit? That way you could could have the pre-filter and water separation in the system with no air bubbles. Also is there a replacement assembly made that will bolt-up to the factory system that way I would not have to use an adapter?
At the risk of opening another can of worms:
www.preporator.com
With all this talk about adding filters, keep in mind what Johnny "technician" might blame if you end up with a driveability problem. Best to keep anything you do completely reversible so if need be you can put it back just like the general delivered...
Just a stupid question, but, Why don't we ask CAT if they would make a filter for the DMAX? Not sure if it's probable that they would do it or not, but a possibility. Well, I guess this is my only way to get into this post since I'm not an individual well versed in diesel fuel filtration.
LA DMAX
LA Dmax; that is an excellent question, however, from my personal experience CAT pretty much denies the existence of any engine that does not have the CAT name on it. Even with all the potential market out there with the literal millions of Cummins, Detroit engines, CAT only makes 2 micron fuel filters for its own engines... CAT is missing a tremendous market, but, you have to know CAT to understand..
SWLA.... I think that would work, but you still run into the sensor on the bottom of the OEM filter. Could throw codes (has anybody disconnected the sensor and ran without it?) You would lose your 'water in fuel' light by removing for sure.
As for the adaptor... that would be fairly easy for a plastics molding company to do probably, but it costs $$$ to engineer a mold, and they would look at it from a standpoint of HOW MANY they could sell. A couple of hundred wouldnt justify the expense. ALSO, the adaptor would only work with one type of filter (fit). Some people might want a larger filter, etc., etc. Cant please everybody!
A secondary filter will more than likely be the way to go IMO, unless a racor or baldwin type company comes up with an absolute product that pleases all.
This is just a thought......what if we installed a filter on the return line. If the fuel is 60% clean in this line, would it be easy to clean it more? I know you would be starting over cleaning the fuel at every fill up. How much fuel gets pushed through the return line in one tank of fuel? If it was in this location you wouldn't need a pusher pump would you? Just some thoughts running through my head.
I would love to hear what Brokers fuel filter set is. Hoot....find out please.
Hello everyone, I may not have any room to talk but I've been following this topic for quite some time and will add my $0.02 worth. As my sig will show I don't, unfortunately, own a Duramax but have installed a primary filter on my 6.5. In its current config I have a 30 micron primary and the OEM (2 micron?) secondary. I did this to protect the lift pump and be able to remove water, if present, easily. I'm curious if having a "rough" filter would increase the efficency of the "fine" or OEM filter? I would be more that happy to provide samples for anyone that is interested in analysis. My personal take is fuel is probably the most variable and definitely the most consumed fluid in our trucks, why not do the best we can to ensure it is clean? I sincerely applaud George's work on the issue.
Kerry
This is a great thread! Very thought provoking! Before it got started, I was ready to install a 2-micron (nominal) Baldwin DAHL 100 filter that I had bought for my 6.5 (never got around to installing it). I had decided to mount it ahead of the cooler and tap the steel fuel line using some Parker FERULOK flareless fittings and braided fuel line…. But now with all the good info being presented here I think I’ll heed JK’s advice and not rush into this.
JK’s point about being able to restore to the factory configuration and the issue of entrapped air has me thinking about the best method (and location) to plumb in the new filter. Also Steve’s following statement raises some interesting questions as well.
“3. Install another clamped hose to feed the pre-filtered fuel to a pusher pump capable of handling diesel fuel for 100,000mi and supplying 5-10psi at 10gph. The outlet of this pump would have the quick connect male fitting, to which the factory fuel line (originally connected to the tank outlet) would attach. This would pressurize the line from that point on and provide the correct conditions for the factory fittings. “
Are the quick connect fittings commercially available? What are the correct conditions for the factory fittings? Since the OEM pump can pull 60inHG, is the purpose of the low-pressure lift pump to reduce susceptibility of creating entrapped air?
Any other thoughts or ideas…?
I am not sure way installing another fuel filter is such and issue, meaning what to use and where to put it. The Ford and Dodge boys have been doing this for some time now. The big setup for the Ford guys is the Racor mounted on the inside of the frame. Hopefuly I will have the proto type mounting brackets Monday or Tuesday and we will be getting some filters installed so we can see the results.
Greg
Mr. Kennedy,
I see you mentioned the Preporator. I have been considering this installation. Quite pricey, but I sure this will take care of any cavitation problems, in which I know we are getting with our 25-30,000 psi systems. I am sure the air is creating the lack of lube problems we see causing pump and injector failures.
If and when I install this system I will keep you posted.
Mike
Greg, What do think is the best way to tap in to the fuel line?
This may sound dumb but why not
put a recirculating pump operated
filter to the fuel tank.The inlet
at one end -outlet at other end.
Greg,
The holes on my C/C are right in front of the fuel cooler on the frame. I was thinking of making a C shaped bracket that fit inside the fram and extended up to the bottom of the bed. That way I could have more room to add my filter.
As for cutting my lines, I will. The service manager is a fiend and he said he didn't care. As a matter of fact he told me to keep him informed of what we were doing and he might pass it up to GM.
Someone ask if anybody made a filter and pump in one assembly and Stanadyne does.
Mr Plock
What I plan to do is cut the line with a tubing cutter right where we mount the filter. When I get the brackets and get it mounted I'll take pictures and show you. Just one cut so if you need to put the fuel line back together all you have to do is use one splice.
Todd
When you see the bracket we have you will not need holes to mount it, it's gong to work real slick, I hope. Sometimes the best laid plans don't work out.
Greg
Greg,
What kind of lines are you going to use? I was going to use high pressure hydraulic lines for ease of fittngs.
What do the lines cost? And what do you think you will sell the bracket for?