Fuel lift pump

[Rockcrusher]

Having just pruchased a new 2002 Quadcab longbed with all the goodies and having read all the horror sories regarding lift pump problems, I am wondering why hasn't DC/Cummins done something about it?

My old 1990 has over 240,000 miles and the only thing to fail was the fuel shut off solenoid. Too bad Cummoins couldnt stick toi the old fashioned mechanical pump.

I also read in the TDR that the folks there have a regular diolog and good relations with Cummins (Cummins Column). Perhaps this issue has be brought up with them and I missed it. Any service bulletins for the 2002s?

I took my new truck on its "maiden voyage" up to Oregon and Washington and on the way back I pulled into Dennys for breakfast and saw a poor guy under the hood of his '96 with fuel all over the ground. The fuel line had totally rotted out.

As someone told me, I had better get fuel pressure guage asap. The newer units should get better not worse! But my new one does run circles around the "more chronologically mature" one.

"I like my truck"

 

[Pit Bull]

Don't worry be happy Congrats on the new truck!!! Mine ran several thousand miles on a dead lift pump Didn't hurt anything (plus now I know I have a strong injection pump) VP44 was designed to run without a lift pump (it's mechanical with electronic control). The lift pump just makes life easier for the VP44 and gives you prime when you change fuel filters. Get a FP guage and when/if it dies have a new one installed under warranty. To many other things in life to worry about besides lift pumps.

 

[Briar Hopper]

A lot of members here with hard-won experience on the lift pump issue will disagree with you, Pit Bull. The lift pump IS something to worry about. The "ostrich" approach to truck problems is not one most of us believe in.

If it's not necessary to the life of the VP44, why is it even on the truck? DaimlerChrysler obviously is aware of it, the pump has been revised and updated several times, with new parts numbers each time (at Cummins, anyway, I don't buy my parts at Dodge if I can help it) and new specifications stating the revised pressure levels it must meet. Why would they bother with all that if it wasn't important?

No harm done? Not quite... . any VP44 that has been run without benefit of a lift pump will see it's life shortened. Maybe not soon, maybe not even for 150,000 miles, but it'll happen.

 

[CumminsPuller]

I am guessing mine ran about 27000 miles on a bad lift pump... ... Thanks to Tom(BriarHopper), I purchased one of his pressure gauge setups and found a very dead lift pump..... boutght a new one from cummins... ... good as new now..... Thanks Tom.



Jason

 

[Lsfarm]

Designed for no lift pump??

PitBull, do you really believe that Dodge would bother with a lift pump if it wasn't needed?



Dodge left off hood liners, rear fender well liners and other ammenities to lower the cost of the truck, don't you think they would have left off the lift pump if it wasn't needed??



The VP44 uses the excess fuel that the lift pump circulates thru it for cooling and lubrication.



The fact that SOME VP44 injection pumps have survived without running lift pumps does not mean that the VP44 doesn't need the cooling and lubrication.



Dodge has even raised the minimum pressure specifications for the lift pump in the last couple of months. This has meant that they are replacing more pumps under warrantee, not less!



Lift pumps are required for long life of the VP44! A fuel pressure guage is required equipment for our CTD trucks. Unless you plan on buying a new one every year!



Greg L

 

[AKostman]

It sure gets confusing listening to all the talk about lift pumps. I plan to install a pressure gauge to monitor. It sure seems Cummins would solve the problem with all the technical knowledge, before this much time elapsed? I really love my truck, it's one of the best vehicles I have ever owned.

 

[24V-DSL]

How to worry less.....

Got a gauge and the latest version of the pump riding along with me.



Seriously, watching the gauge and therefore knowing what's going on, is very calming for me. Changed my fuel filter yesterday, and noticed that I'm running about 2psi less..... still have 12. 5/13 at idle and 12 psi at ~65 mph. 6-9 psi at WOT, but that's pretty much what I've been reading all along. I think the pump is approaching full maturity, so I'm gonna watch real close.

 

[Steve Campbell]

I side with Briar here...



A guage is comforting to one's peace of mind and will pay for itself if used as a tool to change your fuel filter.

 

[Pit Bull]

Originally posted by Briar Hopper

A lot of members here with hard-won experience on the lift pump issue will disagree with you, Pit Bull. The lift pump IS something to worry about. The "ostrich" approach to truck problems is not one most of us believe in.



.

I guess some of you misunderstood my response?



From reading all of the lift pump information on the TDR, some things are clear.



The 98. 5 to current trucks come with lift pumps and they continue to fail.



Dodge/Cummins have revised these pumps many times.



The VP44 was designed by Bosch to operate without a lift pump.



For a while Bosch had a quality control problem with some VP44's

If you have a bad VP44 and a Bad lift pump the combination is deadly to the VP44.



You should check your lift pump with a FP guage, often.



It could be "a good thing" for your lift pump to fail while your under warranty, if you have a marginal VP44 it will then fail and be replaced under warranty. Big $$$





Things we "really" don't know about the lift pump.





Everything else. Members have been trying, many fixes and none seem to work.



I didn't think I was telling him to ignore his lift pump? I told him to get a FP guage and if he had a problem have Dodge replace it under warranty. As far as I understand that is the only known maintance for the lift pump? Briar that is why I bought one of your gauges

 

[Pit Bull]

Re: Designed for no lift pump??

Originally posted by Lsfarm

PitBull, do you really believe that Dodge would bother with a lift pump if it wasn't needed?



(I think the lift pump is needed if only to get prime after a fuel filter change. Also for better fuel mileage, and performance under towing conditions, when more fuel is needed. (things we have noticed problems with when the lift pump was dead)



Dodge left off hood liners, rear fender well liners and other ammenities to lower the cost of the truck, don't you think they would have left off the lift pump if it wasn't needed??



(Needed for the reasons I mentioned above)



The VP44 uses the excess fuel that the lift pump circulates thru it for cooling and lubrication.



(I think your statement is part right. fuel is used to cool the VP44, the lift pump is two pumps in one. One of the pumps draws fuel into the VP44. The lift pump is just making that job easier. The reason that you would have fuel pressure at the inlet of the VP44 is because the lift pump is delivering more fuel then the VP44 wants to take in. From everything I have read fuel flow is more important than pressure. )



The fact that SOME VP44 injection pumps have survived without running lift pumps does not mean that the VP44 doesn't need the cooling and lubrication.



(The VP44 is still getting fuel for cooling and lubrication with a dead lift pump. The VP44 is part lift pump and part injection pump)



Dodge has even raised the minimum pressure specifications for the lift pump in the last couple of months. This has meant that they are replacing more pumps under warrantee, not less!



(Can't argue with that)



Lift pumps are required for long life of the VP44! A fuel pressure guage is required equipment for our CTD trucks. Unless you plan on buying a new one every year!



( I agree that it is better to have a working lift pump and use a FP guage to monitor the lift pump. Since the majority of owners are not TDR members and don't even know this is a problem, I don't think we know what effect this has on the life of the VP44? I would think that if VP44's were dying in any kind of large nembers Dodge would do a recall on the lift pumps. VP44's are a lot more expensive than lift pumps. )



I guess thats the thing we don't know much about the long term effect of bad lift pumps. I will tell you one thing if it caused engines that were toted to be good for several hundred thousand miles to die shortly after the 100K warranty was up it would be a several billion dollar mistake on both Dodge and Cummins part in lost future business. I don't think that either company is that stupid.

 

[Lsfarm]

Disservice to fellow TDR members

The VP44 was NOT designed to run without a lift pump!! To state this is doing a serious disservice to fellow TDR members.



If the lift pump's sole function was to prime the fuel filter canister after a filter change, I'm sure Chrysler would instruct us to fill the canister with a half quart of diesel fuel before reinstalling the top on the fuel filter canister rather than install and warrantee a lift pump on every CTD truck built.



Cummins, Bosch and Dodge install an electric pump costing over a hundred dollars on every truck because the VP44 requires excess fuel flowing through the pump and back to the tank to provide lubrication and cooling.



This is not just for the VP44, on the 12v engines, there is an engine mounted and driven mechanical lift pump that pulls fuel from the tank and provides fuel to the P7100 injection pump.



In both the VP44 and the P7100 there is a very small pre-pump that feeds the high pressure section of the pump with fuel. But this small pump is to FEED the high pressure portion, it is NOT designed to PULL fuel from a fuel tank. It is not a lift pump, it is a feed pump, very low volume output, and requires fuel supplied to it. It may be able to pull fuel if the lift pump dies in some VP44's, but damage is being done!



The electric lift pump on the 98. 5 and later CTD trucks is supposed to provide fuel at a minimum of 8psi at WOT and at least 10psi at idle. Any less than these specs and the dealer is instructed to replace the lift pump. This is to protect and prolong the life of the VP44. This is not so that it is convienient to prime the fuel canister, or to 'improve mileage' or to provide more power. [wouldn't less fuel provide better mileage?]



The minimum pressure specification provides a given flow of fuel through the fuel lines to carry away excess heat from the VP44. When Steve StLaurent installed a temporary fuel tank in his pickup bed to so he could deliver his truck for repairs without the factory fuel tank installed, we discovered just how much heat is being removed from the VP44. A five gallon can of fuel was raised from ambient temperature [50*F] to over 105*F within ten miles of 50 mph driving. [measured with a 'laser' infrared thermometer accurate +/- 1*F] This fuel was pumped to the VP44 via a pusher pump and the factory lift pump to the VP44 and back to the tank. This is the normal flow for fuel in our trucks. This amount of temperature rise proves that without fuel circulating through the VP44 it would be much hotter, have much less lubrication, and fail sooner.



Some VP44 pumps may run without the minimum lift pump fuel pressure, but who wants to gamble just how much the VP44 pump will stand before damage is done, and how much damage can be done to the VP44 before it leaves you stranded beside the road?



There is no way to monitor damage to the VP44, but it is relatively easy to monitor the condition of the lift pump. A full time fuel pressure guage is virtually manditory. A once-in-a-while pressure check is better than nothing.



There are a lot of TDR members who are running a pusher pump at the fuel tank and the factory lift pump on the engine with uninterupted service. This dual pump setup is so far the best fix, and has provided over 40K trouble free miles for several members.



VP44 pumps ARE failing a high rates, that is why the minimum specs for the lift pumps have been raised, so that the expensive VP44 can be protected by the relatively inexpensive lift pump.

If the Vp44 was not at risk from failed lift pumps why would the specs be raised that results in more warrantee replaced lift pumps and expense for Chrysler? So that it is more convienient for us to refill the fuel cansiter after a filter change?? I doubt it!!



Greg L

 

[Rockcrusher]

I really appreciate all the replies. I've been looking at the pressure gauge installation in the latest issue of TDR and dont see the Kit mentioned in listed Geno's catalog 36.

Also where do I inquire about "Briarhoppers" set up? I want a nice clean job and also plan to take my boost gauge out of old unit and put in new. Is 30psi high enough for the '02?

Probably use the "post mount".

Next thing is to find some good step boards so the wife can get in. We used to call them running boards

Thanks again and the more replies the better

 

[Pit Bull]

Re: Disservice to fellow TDR members

Originally posted by Lsfarm

The VP44 was NOT designed to run without a lift pump!! To state this is doing a serious disservice to fellow TDR members.

Greg L

Greg I did not make that up, got it from a post on the TDR from a member that had gotten this information from Bosch (don't think that makes it a disservice to the members of the TDR). I am not saying that we don't want to have a functioning lift pump. Like you said we don't know what damage/if any a dead lift pump does to a VP44. I am sure there are many thousands of Dodge CTD owners out there that don't even know they have a lift pump let alone that it is dead. I imagine that many have well over 100K miles on their trucks and the VP44 is still working. So I guess that the bottom line is, "we don't know", but to be safe you should check your lift pump often with a FP gauge and make sure it is working (we agree on that). I guess what I am trying to say is there is more that we don't know then we do know. This is because of the propriety nature of the Bosch VP44.



Example: Not long ago several members were putting higher output pumps on their trucks. I just read in the new TDR mag. that pumps with too high of pressure are also bad for the VP44. I think were shooting in the dark here, hopefully Dodge and Bosch will figure it out.