Engine/Transmission (1998.5 - 2002) Who's got the new tank mounted lift pump??

[CRead]

Do they replace the hole intire fuel line going to the VP44? Because If its the same size line you can't have any more volume of fuel with out a increase of pressure unless the VP44 is taking in alot more fuel. Right? They say there going off volume now not pressure. But if what I wrote is right it makes the new system worse then the old system. I just put my second LP on in 6 months still having pressure problems. Good news I got the pump at a local MHC Kenworth dealer for about $150 and the delivered it to my work where I gave them a check.

 

[jeepit]

On the intank reto-fit, what is that block where the old pump was located. Just to cover where old pump was??

 

[Bob4x4]

The block allows the origional lines that were connected on both sides of the pump to be reused.



Bob

 

[mhenon]

On the intank reto-fit, what is that block where the old pump was located. Just to cover where old pump was??

Yeah... the block does nothing more than take the place of the OEM LP. No need to change fuel lines or fittings for the dealer doing the install. It accepts the regular banjo fittings like the lift pump.

I'm still thinking about tossing the block and putting a new LP back in place. I just changed fuel filters since getting the truck back from the dealer. With a clean filter. . I did pick up a pound or two of PSI. It doesn't drag down near as fast either. I'll keep two spares with me at all times.

Here are my pressures with a new filter:

1. When I bump the starter (just to get the pump running. . not the engine) I get a steady 8. 5psi

2. Engine running at an idle... 7psi

3. cruising down the road empty... about 4 or 5psi

4. WOT with or without a load... it now stays around 2psi



I'm sure I can suck it down to zero with a heavy load going up hill or something. Just have to make sure I don't do that. What a shame! Now I have to drive it like there's a competitors engine under the hood. Gotta baby it under certain situations. Complete BS.

Maybe we're all paranoid. Maybe this new intank pump will cure everything. I'm just having a hard time figuring out how 2psi under load helps the VP44. If Cummins had only put a real injector pump on this engine (you know... one you don't read about everytime you check into the 2nd generation forum) this would have been a great rig. I have absolutely no complaint with my Dodge. . other then the constent fear that the VP will give out again (with no notice by the way).

With 25K miles left on the warrenty I guess I should just run the snot out of it and "damn the torpedo's"..... or sell it now. I'm really bitter about this whole thing. I've gone from having all the faith in the world in this engine to having none... zero.

Mike

 

[rweis]

IF enough sell their 2nd gen as they reach the 100k mark, those of us that keep our 2nd gen beyond 100k can buy a cheap spare.



Might have to change some neighborhood homeowner restrictions though .



Maybe call it an "art" project, ramps are sort of like a pedalstle, aren't they?



Bob Weis

 

[jeepit]

mhenon, I am currently looking at putting larger lines in with new fittings ( getting rid of all the banjos) and putting a lp back in stock spot. Any thoughts, anyone.

 

[Bob4x4]

mhenon, I am currently looking at putting larger lines in with new fittings ( getting rid of all the banjos) and putting a lp back in stock spot. Any thoughts, anyone.

The larger fittings and lines are a good idea,but I would mount the pump down on the frame rail and not ask it to suck up hill .



Bob

 

[cyborg]

My theory on the stock pump location is that the low pressure in-tank-pump will feed the carter(POS), which will boost the pressure and flow to the VP to acceptable levels. The VP is happy because it gets enough psi and gpm, the Carter LP is happy because it doesn't have to suck (but it does) and the in tank is happy because it doesn't push against resistance.



I'm also wondering if the fuel block they put in place of the lift pump is causing enough of a restriction to to choke the flow down to the numbers were seeing

 

[jeepit]

My theory on the stock pump location is that the low pressure in-tank-pump will feed the carter(POS), which will boost the pressure and flow to the VP to acceptable levels. The VP is happy because it gets enough psi and gpm, the Carter LP is happy because it doesn't have to suck (but it does) and the in tank is happy because it doesn't push against resistance.



I'm also wondering if the fuel block they put in place of the lift pump is causing enough of a restriction to to choke the flow down to the numbers were seeing

I have read that it is 1/4 inch passage. I don't know why they would want it restricted.

 

[24VChev]

You can remove the aluminum block and reinstall a cater lift pump. I would go and the carter pump with pipe thread instead of the banjo fittings. You can make a great system with the in tank/engine mounted pump combo and get rid of all the banjo bolts at the same time. They do use the origonal wires to trigger a new relay but that can be easily adapted to install a engine mounted pump.



Malcolm

 

[Bob4x4]

You can remove the aluminum block and reinstall a cater lift pump. I would go and the carter pump with pipe thread instead of the banjo fittings. You can make a great system with the in tank/engine mounted pump combo and get rid of all the banjo bolts at the same time. They do use the origonal wires to trigger a new relay but that can be easily adapted to install a engine mounted pump.



Malcolm

That holds true on the 2nd gens but with the 3rd gens the origional lift pump is fed through an o-ring into the fuel filter housing,another issue is with the in-tank pump failing you will not get enough flow through it in most cases to run. If that happens you will need a tow.



Bob

 

[Bob4x4]

I have read that it is 1/4 inch passage. I don't know why they would want it restricted.

I have the aluminum block in my hand now,it is a bit more than a 1/4 passage,using my old eyes I would guestimate about11-12 mm. That would probably be less of a restriction than the banjos



Bob

 

[keimmmo]

I have recently changed the filter to VP lines on my truck. The ID of the factory line is 1/4 inch! I had drilled out the banjo fittings right after I got the truck new. Now, I think the factory line is more restrictive than the banjos!!! The hole through the adapter block wouldn't be any more restrictive than the factory line. Going to 3/8 hose with all fittings drilled out to 5/16 ID MINIMUM, I gained 2 psi at idle and 4 WOT over the stock line.



I have been told that the VP NEEDS at least 5 psi at cruise for the internal timing advance to work. Below that you lose power and economy... and VP life.



I have observed over the years that where I live at 5200 ft above sea level the fuel pressure is 2 psi lower than when near sea level. If you take 2 psi off the readings you guys are showing due to my altitude, the new "fix" wouldn't maintain more than a couple of psi at cruise and 0 WOT!!! I think I'll stay with the system I have until I see something that HONESTLY looks better!



Steve Keim

 

[Sageair]

I just installed the Vulcan big line kit and relocated my old LP to the frame near the tank using Vulcan relocate kit. I cannot pull the presuure down to 5 p. s. i now. It was quite easy to see less than 5. ps. i before.