Engine/Transmission (1998.5 - 2002) Wanna fix your lift pump problems?

[Diesel Freak]

Great Post Terry!



Has anyone had any luck replacing the 3/8 stainelss line and tank pickup with 1/2 inch line?



I know of one individual that tried this with very little success... .

 

[Behr]

Originally posted by Diesel Freak

Great Post Terry!



Has anyone had any luck replacing the 3/8 stainelss line and tank pickup with 1/2 inch line?



I know of one individual that tried this with very little success... .

Diesel Freak. . :-{} ... I feel or in my opinion if the pump is as close to the supply source as possible then I am not sure changing the size of the fuel line from the tank to the pump would really be an advantage.



I do feel though that once coming out of the pump up to the fuel filter a larger line for that distance would be beneficial.





Gordon

 

[Gary - K7GLD]

Terry up above has made the same point concerning top vs bottom draw of fuel some of the rest of us have - to distill it to the most basic terms:



Regardless of placement of a pump in relation to the source, there is absolutely NO difference, or ADVANTAGE in drawing from the bottom vs drawing off the top, *all other factors being equal*, PERIOD!



Plain, simple grade school physics...



BUT, if it gives ya a warm and fuzzy feeling to drill a hole in the bottom of yer tank, and pull outta there, have at it...

 

[Pit Bull]

I know that one of the early recommendations for keeping the LP working was to alway keep your tank above 1/2 full. This seems to go along with your theory. When you talk about FP, in early discussions on this topic and experiments by members like Bill K FP was not determined to be as important as flow. Meaning as long as you alway had some positive FP then the VP44 was getting all the fuel it needed. Anybody want to discuss this issue? :-laf

 

[Gary - K7GLD]

I have no doubt that providing a LARGER fuel line from the bottom of the tank to the pusher pump inlet will possibly provide enhanced fuel flow, and perhaps slightly more pressure as well - but doing the same thing with the existing line and location would do the same thing... That's why I included the "all things being equal" up above...



As time goes by, I get less and less concerned about this LP "issue" - it's really relatively minor in the overall scheme of things - simply something to be aware of and monitor - the common "fix" is easy and relatively inexpensive to provide - certainly FAR less intrusive than earlier auto transmission failures, brake problems, 5th gear nuts on 5 speed trannies and such - THOSE would worry ME far more than a simple LP problem...



THEN, there's all the problems the Ford guys are having with THEIR new trucks - makes OUR LP problems seem trivial...

 

[Pit Bull]

Originally posted by Gary - KJ6Q



THEN, there's all the problems the Ford guys are having with THEIR new trucks - makes OUR LP problems seem trivial...

Amen brother, perspective is a great thing to have

 

[Behr]

A quick couple of questions... .



Does anyone know who the OEM lift pump is manufactured by... ??

:-{}

Also... . if I was to purchase a lift pump from Cummins... . would it be the same pump as from a Dodge Dealer... ??

:-{}

Last question is... . are all the lift pumps the same on all ISB engines... . ??

:-{}

 

[Ncostello]

1. Carter

2. Yes, but the box wouldn't have a Mopar label over the Cummins Label

3. Yes, however there was a slight modification to the pumps in around 2000 or 2001. They changed the plug and how its protected from the elements. Thus 99 and older models require a short adapter "pigtail" harness that adapts the two different plug types.

 

[Behr]

Originally posted by Ncostello

1. Carter

2. Yes, but the box wouldn't have a Mopar label over the Cummins Label

3. Yes, however there was a slight modification to the pumps in around 2000 or 2001. They changed the plug and how its protected from the elements. Thus 99 and older models require a short adapter "pigtail" harness that adapts the two different plug types.

Neil..... thank you for the info... . mine is a 2001



I am hoping in the next couple of weeks of doing some changes to the fuel delivery system.



First thing I need to get is a fuel pressure gauge installed.....



Gordon

 

[Ncostello]

You wont need the pigtail adapter since your engine wiring harness has the correct plug for the revised pump.



However in my case I dont mind the harness adapter because it provides me with a starting point for lengthening my factory wiring back to a relocated pump. The plugs are included and all I have to do increase the length of the wires of the Cummins adapter. I dont want to lengthen/cut/splice any wires that are part of the engine block wiring harness so this adapter is perfect.



You only need one end of the Cummins adapter ($8. 00). Then you will have to find a female plug that will tie into your engine wiring plug for the lift pump... unless you want to cut and splice. This is assuming your moving the pump and just extending the factory power supply wires.

 

[Behr]

Neil..... I was debating on whether to move the pump back to the tank... . then run an over size fuel line 1/2 inch to the filter... . or

to just drop the pump down so its slightly lower than the tank.



I will have to crawl back in under the truck and see if I can find a good home to mount it.



I really think putting in the over size fuel line will help take a load off the pump... .



Do you have FP gauge on yours... ??



What do you recommend..... mechanical or electronic... ??





Gordon... .

 

[Ncostello]

Actually I feel simply moving the pump to a lower elevation is good. That coupled with a larger (even slightly) supply line should produce the desired effects. It would also keep my extended wiring to the LP as short as possible. My optimal location for the LP is right were the stock steel line takes a turn up towards the fuel filter canister down there on the frame.



I run a mechanical (internal fluid filled) gauge (el-cheapo 2" hydraulic gauge 0-30psi... want to upgrade to Autometer). On my fuel canister (which is different than yours) I come off the cannister post filter port with 1/8"NPT to 3AN braided stainless 90. It then goes through the firewall to the gauge. The gauge is mounted where the ash tray is supposed to be. Its slightly lower than the fuel canister so air will naturally bleed out and fluid will keep the line full. I cant recommend which is best. I just like mechanical gauges.

 

[Diesel Freak]

Originally posted by Behr

Diesel Freak. . :-{} ... I feel or in my opinion if the pump is as close to the supply source as possible then I am not sure changing the size of the fuel line from the tank to the pump would really be an advantage.



I do feel though that once coming out of the pump up to the fuel filter a larger line for that distance would be beneficial.





Gordon

The fuel is the life blood not only for the VP44, but also the Carter fuel pump... regardless of it's location.



A larger line leading to the pump suction can only help it along!

 

[Behr]

Later this week... I will be crawling under my truck to figure out best location for the pump.



Probably as close to the tank (source) would be the best... . but until I get under there and take a good look. Two things I do know that I will change is the size of the delivery line... . and secondly make sure the pump is lower than the tank (source) if possible. .



Ohhh... and I will always keep a spare lift pump in the truck... .

 

[daveshoe]

good stuff here , but

I got the simple mechanical gauge described above and am making good numbers at 15 K. Before I jump in this mod ,I have some questions for the new members and mechanically challenged [ME]

The fuel line has sections that are rubber and some that are steel. Where have you made the cut on your application for pushers ect?

If I remove the OEM pump from it's factory location and mount as a pusher, what kind of fittings would you use to take the place of the original pump location. BTW anything has to be better than the little plastic clip that attaches the OEM line to the suction side of the pump.

Also, as a favor to some new members who wanted R&R instructions on lift pumps-- I was not successful in locating a good thread on lift pump replacement. [There is so much stuff to go through]

I realize that these may be questions better suited to the new members site, but similar questions were recently moved to this site anyhow. Thanks in advance

 

[Gary - K7GLD]

Well, ACTUALLY, in case you hadn't noticed, right in this very thread, there is a PICTURE of an added pusher installation, and it would be typical of most others in use, or for those where the stock LP was simply moved back near the fuel tank - perhaps the picture isn't clear enough - but what's displayed, is a section removed from the existing steel fuel line to accomodate the insertion of the pictured pump and filter - diesel fuel compatible hose is used to adapt from the remaining steel line to the brass hose barbs in and out of the added pusher pump, and could also easily be used to bridge where the original LP is now located, if you prefer to simply move it back closer to the tank - all needed, is a longer section of hose running fron the engine end of the steel fuel line, to it's new termination at the fuel filter, bypassing the stock LP location... It's all right there to see...



Capeesh?

 

[daveshoe]

Capeesh--- Yes, and I feel the love

 

[d.miner]

lift pump

I agree with KRS... sounds like a high level corp. decision to make things easy for them.



It seems to me that moving it off the engine and onto the frame rail will also greatly reduce vibration. I remember reading about one member doing this and then putting a small piece of rubber between the frame rail and the pump just to aid in reducing vibration.



I would be curious... maybe we're not asking the right question, How many owners that have moved their pumps have suffered a failure? If the answer is less than 1%, that would support this thread and help a lot of us out.



Food for thought.



Dan

 

[daveshoe]

The magic durable pump?

I think we have two schools of thought on this thing. Some want to help out the stock pump to survive the high intermittent fuel requirements . Some want to basically improve the basic design , but are not crazy about altering an otherwise stock truck-- Who knows if a dealer might give one a hard time for just moving the stock LP like Whitmore suggests.

I was servicing a John Deere 4630 today and the simplicity of this thing sort of struck me. If you could find a DEAD RELIABLE low pressure pusher pump, to help the stocker , then it would be as close to Kevin's idea as some of us are comfortable with.

The guys at the John Deere dealership were kind enough to give me the numbers on their only lift pump application -- for a combine. This pump is mounted low and pushes a long way. Numbers are 12 gallons per hour and 3-5 PSI . It is a very long service life pump and the only pre pump filtration is an easily serviced screen. The only disadvantage I can think of is the normal fuel for this thing is red offroad. Lubricity issues??

If these numbers are enough for a pusher, please advise. If they are not. There may be other ag application pumps that will get us there. At 65 bucks, I would have no problems trying one.

Any thoughts or criticisims are welcome, so flame away

 

[Diesel Freak]

Re: The magic durable pump?

Originally posted by daveshoe

Numbers are 12 gallons per hour and 3-5 PSI . It is a very long service life pump and the only pre pump filtration is an easily serviced screen. The only disadvantage I can think of is the normal fuel for this thing is red offroad. Lubricity issues??

The pump is way to small..... needs to be closer to 120 GPH and 15 PSI. The offroad fuel is not an issue... it is the same as onroad fuel except that it has red dye and you don't pay road tax on it.