Fuel system question
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I was talking with the tech at my local dealer while they upgraded my 2002 software and he was telling me they had to replace 2 injectors and one inj pump in the 3 years the 6.6 has been out. He said it was pretty amazing but the inj pump had self destructed with pieced in the engine compartment, but the truck was driven into the shop and ran, although with less power.
lift pumps. Having put over 750,000 miles an a couple of 6.2s I found the trucks would run without the lift pumps. The service manager told me that it could have been a couple years like that. The biggest problem with the lift pumps is caused by them freezing in the winter.
Like HOOT said the dodge and gm setups are a "system" . The older Fords used the same inj. pump gm used , however gm needed to put a flow shut off in the pumps so they wouldn't loose prime , get air and Ford didn't.
Are the injectors on the d max more tempermental than those on the 6.2 ? I got 425,000 miles out of my original injectors on my 88 6.2
Terry
Northeast Diesel Gettogether Sept 27
www.dieselgettogether.com
lift pumps. Having put over 750,000 miles an a couple of 6.2s I found the trucks would run without the lift pumps. The service manager told me that it could have been a couple years like that. The biggest problem with the lift pumps is caused by them freezing in the winter.
Like HOOT said the dodge and gm setups are a "system" . The older Fords used the same inj. pump gm used , however gm needed to put a flow shut off in the pumps so they wouldn't loose prime , get air and Ford didn't.
Are the injectors on the d max more tempermental than those on the 6.2 ? I got 425,000 miles out of my original injectors on my 88 6.2
Terry
Northeast Diesel Gettogether Sept 27
www.dieselgettogether.com
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2,536 Posts
I gathered from the below Kennedy post of 5/19/03, that you bought it from him. I guess he gave it to you? Yep, The lift pump was a trade off for information gathering while John was busy getting ready for the Dino Run. I earned the pump. I have nothing to hide.
Dig! Dig! Dig! You will never catch me in a lie. I told you in the past It's not my style. The truth is always easy to remember.
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Dig! Dig! Dig! You will never catch me in a lie. I told you in the past It's not my style. The truth is always easy to remember.
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3,039 Posts
When trucks with a stock fuel system (no lift pump) and a set of bigger injectors can throw out black smoke like a coal fired locomotive from 0-100+ mph I wouldn't say the injecton pump is starving for fuel.
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26 Posts
BY PUSHING FUEL THRU A BETTER THAN THE OEM FILTER WITH NO WORRIES OF ADDITIONAL RESTRICTION OR AIR ENTERING THRU OEM FITTINGS DESIGNED ORIGINALLY FOR PRESSURE. iF YOU PREFER YOUR SYSTEM TO SUCK THATS YOUR CHOICE.........GOD HELP US WE DO AGREE THAT CLEANER FUEL IS BETTER.........
VINNIE
PS
I DO HAVE A LIFT PUMP( A FM 100 FOR 10K MILES) AND I PURCHASED IT FROM RELIABLE..........IT WAS NOT A GIFT BUT X I WILL ALLOW YOU TO PAY FOR IT AND ILL BE YOUR FRIEND.........PAYPAL TO [email protected] $200 WILL BE ENOUGH AFTERALL ITS USED
VINNIE
PS
I DO HAVE A LIFT PUMP( A FM 100 FOR 10K MILES) AND I PURCHASED IT FROM RELIABLE..........IT WAS NOT A GIFT BUT X I WILL ALLOW YOU TO PAY FOR IT AND ILL BE YOUR FRIEND.........PAYPAL TO [email protected] $200 WILL BE ENOUGH AFTERALL ITS USED
mtomac,
I guess the concern is that the addition of a 2 mic filter may cause too much restriction for the current pump. Are you running with an aftermarket filter too?
Frank Blum aka Turbo Diesel, said it wasn't that much of a restriction to worry about:
4/11/03:
I think adding a lift pump is totally unnecessary and would open up a can of worms. I can count on one hand the industrial systems I've seen with a charging pump. The data that came with my Racor said the pressure drop is .05 @ 30 PSI. I don't know how much it would add to the total suction head. I suspect not very much. Later!
I guess the concern is that the addition of a 2 mic filter may cause too much restriction for the current pump. Are you running with an aftermarket filter too?
Frank Blum aka Turbo Diesel, said it wasn't that much of a restriction to worry about:
4/11/03:
I think adding a lift pump is totally unnecessary and would open up a can of worms. I can count on one hand the industrial systems I've seen with a charging pump. The data that came with my Racor said the pressure drop is .05 @ 30 PSI. I don't know how much it would add to the total suction head. I suspect not very much. Later!
Turbovinnie,
I want my system to do what it was designed to do and in this case - it sucks (pun intended) We have folks like MTomac running high 12' in the 1/4 with it just sucking. He just said at WOT with an even bigger set of injectors the truck/pump doesn't appear to be fuel starved at all.
Even Kennedy does not see any value to a lift pump other than preventing "outgassing" or vapor bubbles in the fuel line which chuntag95 has found to be normal in our trucks:
Kennedy 4/11/03,
...Aside from possible "outgassing" and vac leak elimination, I really see no need for a lift pump. There just isn't a ton of flow in this thing, just STEADY flow...
I want my system to do what it was designed to do and in this case - it sucks (pun intended) We have folks like MTomac running high 12' in the 1/4 with it just sucking. He just said at WOT with an even bigger set of injectors the truck/pump doesn't appear to be fuel starved at all.
Even Kennedy does not see any value to a lift pump other than preventing "outgassing" or vapor bubbles in the fuel line which chuntag95 has found to be normal in our trucks:
Kennedy 4/11/03,
...Aside from possible "outgassing" and vac leak elimination, I really see no need for a lift pump. There just isn't a ton of flow in this thing, just STEADY flow...
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but as I believe mike can confirm he is running no additional filter yet. there are some fairly quick dmaxes that run more than one filter and a lift pump whether you deem it necessary or not......
ps
cashiers check or money order will be fine.......but nothing personal
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Edited by: TurboVinnie
ps
cashiers check or money order will be fine.......but nothing personal
I'll be the first in line to get a lift pump if it will prolong the life of my truck. But so far it only appears to be introducing a weak link, except for some to prevent some (unmentionable) problems.
Does yours have by-pass flow if it quits/malfunctions. I'm not trying to be an alarmist. But just check over at the Cummins sites. Or, run a google search for "VP44 lift pump."
Their OEM pumps are crapping out and destroying the VP44. They are going after market with the Carters but they also do not allow flow when they quit.
The main problem for the injection pumps is insufficient lubricity with the low sulfur fuel. Additives add much needed lubricity.
Does yours have by-pass flow if it quits/malfunctions. I'm not trying to be an alarmist. But just check over at the Cummins sites. Or, run a google search for "VP44 lift pump."
Their OEM pumps are crapping out and destroying the VP44. They are going after market with the Carters but they also do not allow flow when they quit.
The main problem for the injection pumps is insufficient lubricity with the low sulfur fuel. Additives add much needed lubricity.
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yes two valves and its back to oem and it works
on edit if you can get those little bubbles to go away with pressure in stead of suction theres a good chance the spray and atomization of fuel will be better and a increase in fuel economy might appear........my heavy right foot has not relented.....but the last dozen or so tanks seem to reveal 30 or so more miles per tank
VEdited by: TurboVinnie
on edit if you can get those little bubbles to go away with pressure in stead of suction theres a good chance the spray and atomization of fuel will be better and a increase in fuel economy might appear........my heavy right foot has not relented.....but the last dozen or so tanks seem to reveal 30 or so more miles per tank
VEdited by: TurboVinnie
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1,292 Posts
Mr X, I am not Turbo Diesel anywhere. I am Lone Eagle on the diesel page and lately I have been using my given name there also. My post talked about the Racor only and as far as I know the Racor following aren't using an additional lift pump. If I were having drive ability problems I would put one on in a heartbeat. I believe we need the additional filter and what ever hardware necessary to prevent cavitation/outgasing/stalling/priming etc. I don't know why GM chose to bolt the lift pump to the HP pump. If I had a 100K on mine, I would trash both filters and install a Mega in the OEM location. For now, I will run what I have and watch it. Later! Frank
I'm running Post OEM Racor 690R2. No problems and no lift pump. That doesn't mean the other options are better or worse but I must concede that the more you filter, the more vacuum you create which means a lift pump helps.
No doubt in my mind.
Mr X. If you don't like the lift pump idea, just say so
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Edited by: hoot
No doubt in my mind.
Mr X. If you don't like the lift pump idea, just say so
I've said it a hundred times, I'll be the first in line to get one if it will prolong the life of my truck. So far, the "experts" that I've read (Kennedy, Frank Blum among others) say either it isn't recommended, or, it is only needed to stop air from forming in the fuel lines, which, we have learned from Chuntag95, is normal and occurs in stock trucks.
One concern is the flow restriction but George Morrison put that one to rest a long time ago saying our pumps had more than enough pull to deal with an added filter:
10/27/02:
In talking with a Racor engineer last week, our Bosch pump is consertavitely rated 60 inches! Our current OEM filter draws less than 8 inches, so an additional filter is no problem; in fact GM is currently working on a primary to put in between the present filter and the tank. What do you think that is telling us
It can therefore easily handle a both a primary and secondary fuel filter, especially if one or both are synthetic or microglass media. Moreover, if it is 'clean' fuel that the pump is processing, THAT is the key to both pump and injector life. i.e. if the pump has twice the load, if the fuel is ultra-clean, the increased load is much better than processing dirty fuel at half the load..
George Morrison, STLE CLS
Frank Blum,
Did you say those words that I attributed to you? In effect saying, "A lift pump is opening a new can of worms." Isn't teh RACOR the smallest an dpotentially the most restrictive between the CAT, MEGA and RACOR?
I agree if you have driveability problems, stalling etc. you need a lift pump. Experts on teh Aftermarket Fuel Filter thread dismissed teh cavitation and outgassing as not a concern.
DieselGod,
Once again mostly negative personal BS but no real diesel-related contribution.
BTW, how can you be a diesel god if you don't even know we have the VP44 injection pumps in our trucks? It is also coupled with a gear type lift pump to feed it.
So, according the experts, unless it's fixing stalling/driveability problems, the lift pump ain't doing jack except introducing a weak link (60,000 service life) in your 225,000+ mile fuel system.
Brokers has two trucks, 800,000 combined miles w/o lift pumps running pre-oem RACORS. He's no more a myth than diesel god or GM smitty aka smitty. But, just becauwse he is saying something you don't want to hear, (that maybe you are barking up the wrong tree with this lift pump), you defame him, assassinate his character and try to ignore his good, positive news about our trucks.
Same "good ole boys" crowd in here doing the same crap as over on TDP. If you go against their line of reasoning, you'll get swarmed with a bunch of personal crap until they force the topic to be closed.
Once again, if you can show me solid evidence that a lift pump actually prolongs the service life of my truck, I'll install one the same day.
One concern is the flow restriction but George Morrison put that one to rest a long time ago saying our pumps had more than enough pull to deal with an added filter:
10/27/02:
In talking with a Racor engineer last week, our Bosch pump is consertavitely rated 60 inches! Our current OEM filter draws less than 8 inches, so an additional filter is no problem; in fact GM is currently working on a primary to put in between the present filter and the tank. What do you think that is telling us
It can therefore easily handle a both a primary and secondary fuel filter, especially if one or both are synthetic or microglass media. Moreover, if it is 'clean' fuel that the pump is processing, THAT is the key to both pump and injector life. i.e. if the pump has twice the load, if the fuel is ultra-clean, the increased load is much better than processing dirty fuel at half the load..
George Morrison, STLE CLS
Frank Blum,
Did you say those words that I attributed to you? In effect saying, "A lift pump is opening a new can of worms." Isn't teh RACOR the smallest an dpotentially the most restrictive between the CAT, MEGA and RACOR?
I agree if you have driveability problems, stalling etc. you need a lift pump. Experts on teh Aftermarket Fuel Filter thread dismissed teh cavitation and outgassing as not a concern.
DieselGod,
Once again mostly negative personal BS but no real diesel-related contribution.
BTW, how can you be a diesel god if you don't even know we have the VP44 injection pumps in our trucks? It is also coupled with a gear type lift pump to feed it.
So, according the experts, unless it's fixing stalling/driveability problems, the lift pump ain't doing jack except introducing a weak link (60,000 service life) in your 225,000+ mile fuel system.
Brokers has two trucks, 800,000 combined miles w/o lift pumps running pre-oem RACORS. He's no more a myth than diesel god or GM smitty aka smitty. But, just becauwse he is saying something you don't want to hear, (that maybe you are barking up the wrong tree with this lift pump), you defame him, assassinate his character and try to ignore his good, positive news about our trucks.
Same "good ole boys" crowd in here doing the same crap as over on TDP. If you go against their line of reasoning, you'll get swarmed with a bunch of personal crap until they force the topic to be closed.
Once again, if you can show me solid evidence that a lift pump actually prolongs the service life of my truck, I'll install one the same day.
Mr. X said:
Once again, if you can show me solid evidence that a lift pump actually prolongs the service life of my truck, I'll install one the same day.
Phil, I think they install the lift pump so they can make their signature longer.
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Seriously, the guys going the lift pump route were having accumulated air problems so they tried the pump.
Notice no one ever thought about a lift pump until the Mega came. Not knocking the Mega but that's where the realization that vacuum and added filter restriction could cause problems.
Reducing undissolved air could improve fuel injector spray pattern and efficiency.
You are jumping all over durability when that's not the only reason. These trucks run better and get better mileage when the fuel is filtered down to 2m. That has been pretty much accepted.
It is also possible that a lift pumped system which I think we all agree helps maintain solution, also improves injection performance, hence, engine performance.
I have no proof.
Rumour has it the 2004 injectors have a different spray pattern.
Edited by: hoot
Once again, if you can show me solid evidence that a lift pump actually prolongs the service life of my truck, I'll install one the same day.
Phil, I think they install the lift pump so they can make their signature longer.
Seriously, the guys going the lift pump route were having accumulated air problems so they tried the pump.
Notice no one ever thought about a lift pump until the Mega came. Not knocking the Mega but that's where the realization that vacuum and added filter restriction could cause problems.
Reducing undissolved air could improve fuel injector spray pattern and efficiency.
You are jumping all over durability when that's not the only reason. These trucks run better and get better mileage when the fuel is filtered down to 2m. That has been pretty much accepted.
It is also possible that a lift pumped system which I think we all agree helps maintain solution, also improves injection performance, hence, engine performance.
I have no proof.
Rumour has it the 2004 injectors have a different spray pattern.
Edited by: hoot
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Mr. X,
Since I do not know anything about a fuel system I will play devils advocate with you.
I have just a few questions, and then I hope to put my filter knowledge to bed
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First off, isn't the gm/bosch common rail sytem a vaccum draw from the tank thru the filter in comparison to a lift pump which I assume would be a push to the filter and on thru.
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Second, why do you want a push / pull system??? in my estimation only one is needed.
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Three, does air not always rise to the highest point or does it function like a brake / hydraulic system is it not pushed to a place it can escape from??? IE a bleeder or thru an injector????
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Why does only some secondary fiter designs trap air while others do not and do they pass the air thru the injectors or simply thru the return line of the common rail only to be returned to the fuel tank ??
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I guess my final comment without being sarcastic as I am not trying to be, what does it matter???
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If you want secondary filtration then I beleive you and everyone else can and will choose an avenue that best fits their own personal budget and preference.
If you want to know I will be running a pre oem cat setup.
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In my estimation for mounting location, ease of fiter change and cost of filters as well as filter availability and the simple fact that I won't need a lift pump are my reasons.
I don't need to entertain any other system as I know what I want and am happy with my choice.
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I will only bleed out air on fiter changes. In my estimation a idiot proof system.
I do appreciate your comments as well as everyone elses.
TO EACH THERE OWN.
This is why we are all here.
If the horse is dead
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, let us not beat it any further shall we...........
GMC aka ---> T
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NY
Feel free to continue if you wish, we are an open book.
Since I do not know anything about a fuel system I will play devils advocate with you.
I have just a few questions, and then I hope to put my filter knowledge to bed
First off, isn't the gm/bosch common rail sytem a vaccum draw from the tank thru the filter in comparison to a lift pump which I assume would be a push to the filter and on thru.
Second, why do you want a push / pull system??? in my estimation only one is needed.
Three, does air not always rise to the highest point or does it function like a brake / hydraulic system is it not pushed to a place it can escape from??? IE a bleeder or thru an injector????
Why does only some secondary fiter designs trap air while others do not and do they pass the air thru the injectors or simply thru the return line of the common rail only to be returned to the fuel tank ??
I guess my final comment without being sarcastic as I am not trying to be, what does it matter???
If you want secondary filtration then I beleive you and everyone else can and will choose an avenue that best fits their own personal budget and preference.
If you want to know I will be running a pre oem cat setup.
In my estimation for mounting location, ease of fiter change and cost of filters as well as filter availability and the simple fact that I won't need a lift pump are my reasons.
I don't need to entertain any other system as I know what I want and am happy with my choice.
I will only bleed out air on fiter changes. In my estimation a idiot proof system.
I do appreciate your comments as well as everyone elses.
TO EACH THERE OWN.
This is why we are all here.
If the horse is dead
GMC aka ---> T
Feel free to continue if you wish, we are an open book.
hoot and GMC-2002-Max,
I only know what I've read in here, TDP and on the internet. gwmayes says that the air in the fuel is like air in a freshly poured glass of water with all the little bubbles in it. It's in there and aerates out w/o being under pressure BUT and then re-compresses back into little bubbles under pressure. This is what is occurring in our stock fuel system.
Under the pressures of the pumps, the air that was visble as air bubbles in the clear line tests gets put back into solution as smaller air bubbles. Whether large or small as in entrained air, these air bubbles produce the same effect, (Unless of course something is trapping all the air and causing problems). Once injected the air in these bubbles combines with the intake air for combustion.
Therefore, since the air still remains in the fuel, even with a lift pump, I believe the only hp gain could be achieved by removing the air with one of those fuel/air separators.
I believe that if a lift pump actually did contribute to more hp, mtomac and Kennedy would have mentioned it by now. But as Kennedy has been saying all along, beyond keeping the air/vapor entrained, the lift pump does not do much else and is not needed to pump fuel.
Combined with gwmayes and DuramaxAlliTech dismisssal of the air/outgassing and/or cavitation problems as false alarms, it appears the only real problem this air/vapor has caused is loss of prime and stalling on certain (unnamed) filtrers mounteed in certain (unnamed places).
Otherwise the air/vapor normally found in diesel #2 results in bubbles normally found in the fuel lines of our stock trucks past the EDU.
Finally, we have just learned from the experts that we had mistakingly equated vapor and air-filled bubbles with cavitation when, in fact, the air bubbles do not do the same harm as does cavitation which is airless voids (cavities) in the fuel.
Out of here!
I only know what I've read in here, TDP and on the internet. gwmayes says that the air in the fuel is like air in a freshly poured glass of water with all the little bubbles in it. It's in there and aerates out w/o being under pressure BUT and then re-compresses back into little bubbles under pressure. This is what is occurring in our stock fuel system.
Under the pressures of the pumps, the air that was visble as air bubbles in the clear line tests gets put back into solution as smaller air bubbles. Whether large or small as in entrained air, these air bubbles produce the same effect, (Unless of course something is trapping all the air and causing problems). Once injected the air in these bubbles combines with the intake air for combustion.
Therefore, since the air still remains in the fuel, even with a lift pump, I believe the only hp gain could be achieved by removing the air with one of those fuel/air separators.
I believe that if a lift pump actually did contribute to more hp, mtomac and Kennedy would have mentioned it by now. But as Kennedy has been saying all along, beyond keeping the air/vapor entrained, the lift pump does not do much else and is not needed to pump fuel.
Combined with gwmayes and DuramaxAlliTech dismisssal of the air/outgassing and/or cavitation problems as false alarms, it appears the only real problem this air/vapor has caused is loss of prime and stalling on certain (unnamed) filtrers mounteed in certain (unnamed places).
Otherwise the air/vapor normally found in diesel #2 results in bubbles normally found in the fuel lines of our stock trucks past the EDU.
Finally, we have just learned from the experts that we had mistakingly equated vapor and air-filled bubbles with cavitation when, in fact, the air bubbles do not do the same harm as does cavitation which is airless voids (cavities) in the fuel.
Out of here!
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26 Posts
since "you" only know what you have learned from the internet know this:
there are benefits to the lift pump/additional filter scenario :
1. additional filtration without additional restriction.
2. better performance(inregards to fuel atomization and injector pattern) which would help produce more fuel economy.
3. fuel thats pushed intead of sucked reduces the liklyhood of air sucked in thru connections designed for pressure.
4. the ability to add an additional tank(s) and plumb easilly into the lift pump housing.
5. priming after a filter change with the twist of a key.
6. and most important, having something that X(hb) does not have giving him something to ***** and rant about, so people will talk to him.
vinnie
ps im still waiting on my friendship moneyEdited by: TurboVinnie
there are benefits to the lift pump/additional filter scenario :
1. additional filtration without additional restriction.
2. better performance(inregards to fuel atomization and injector pattern) which would help produce more fuel economy.
3. fuel thats pushed intead of sucked reduces the liklyhood of air sucked in thru connections designed for pressure.
4. the ability to add an additional tank(s) and plumb easilly into the lift pump housing.
5. priming after a filter change with the twist of a key.
6. and most important, having something that X(hb) does not have giving him something to ***** and rant about, so people will talk to him.
vinnie
ps im still waiting on my friendship moneyEdited by: TurboVinnie
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1,292 Posts
You funny Hoot. I am not responding to you know who again. My wife knows more about this topic than he does. I just got back from a 450 mile trip up near Jackson Hole, Wyoming. I went to the same place at the same time of year last year. Mileage was better this year by 1.9 MPG. Only change was more miles on the truck and the secondary filter. Go figure! Later! Frank
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