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1tuffram

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I know this has been discussed in the past, but since the search is not working..... (well you know). Can the C- series lift pump be adapted to work for us. I can not remember what the snag was for making it possibly work. What lift pump is used on the C-series? Is it a Carter or some other manufacture's??



Anyone know what the Big Rig diesels are using for lift pumps?



Maybe we need to start "thinking outside the box". What I'm getting at is for the most part all the various lift pumps people have been using are intended for automotive applications. It just seems these automotive type lift pumps are not designed for the continous duty cycle our application demands. Maybe we need to start looking into what is being used by the heavy diesel indusrty, etc. Just thinking out loud.
 
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Maybe we need to start "thinking outside the box". What I'm getting at is for the most part all the various lift pumps people have been using are intended for automotive applications. It just seems these automotive type lift pumps are not designed for the continous duty cycle our application demands. Maybe we need to start looking into what is being used by the heavy diesel indusrty, etc.

I agree hole heartedly and feel that the factory lift pump moved back to the tank will solve all the probs. Remember that the problem is placement... not neccessarily the pump. Just my . 02
 
Chipstien,



True, but I'm still reading reports of pumps eventually crapping out even when placed near the tank. I think relocating the pump just prolongs the enevitable, all these pumps just are not up to the task (of coarse the many feet of line the lift pumps have to pump fuel through dosn't help matters).



Maybe we need to relocate the FUEL TANK to the front bumper, that would cut several feet off the distance a tank mounted lift pump would have to work against:rolleyes: ;)
 
I looked into using the lift pump for the ISC on our ISB trucks. The pump motor is indentical, but it has a big aluminum casting on it with like 6 ports on it, all of which are 3/4" NPT thread. Waaaay too big for our application. So I elected to use a Carter 4601HP pump mounted on the frame rail just ahead of the tank. I ran all new line from the tank to the pump (3/8" ID hose). I also ran all new line from the lift pump to the filter, and then onto the injection pump. For all this I used -06AN braided stainless and anodized fittings.



The one thing I have found that makes a big difference is supply line size. I'm not talking about the size on the pressure side of the pump, rather the suction side. All the motorhomes and heavy trucks I work on that are equipped with the ISB use at least 1/2" supply line from the tank to the pump. Some are even using 5/8" line. The lift pump is the same as the one on the Dodge trucks, and is mounted in the same spot on the side of the engine.



On the motorhomes, the tank is a long ways from the engine, sometimes more that 15 feet. Not once have I ever seen one with low pressure, and I attribute the good readings to the size of the supply line.



Dodges use a 5/16" ID steel line for the supply...



Food for thought...
 
Thinking outside the box.

How about a marine application? I don't mean what Cummins is using, there's probably an aftermarket marine service lift pump that would fit our application. I'll look around when I go into town later, but maybe someone on here has some idea?
 
Re: Thinking outside the box.

Originally posted by 85CJ

How about a marine application? I don't mean what Cummins is using, there's probably an aftermarket marine service lift pump that would fit our application. I'll look around when I go into town later, but maybe someone on here has some idea?



I was wondering that myself. When doing a search (on internet) for elec fuel/lift pumps I came across a diesel marine site. It listed some "oil/diesel transfer pumps". I looked at them and they looked similar to our lift pumps, only larger. Think they used 3/4" fittings and had flow rates of 4-7. 5 GPM. for oil and said flow rates where higher for "thinner" liquids. No psi ratings and the flow rates are probably way too much for us. Think the name of the manufacture was Groco or something like that. There was not any info about the elec motor size or if they where designed for 100% continous duty. I got the impression they where not. and intended for intermitently transfering of fluids. So I moved on and started searching sites which claim to sell replacement parts for Kenworth, Pete, Mack, Paccar, etc. but came up empty handed for anything regarding lift pumps. I found Lots of websites dealing with fuel "injection" pumps and injectors, but nothing on electric fuel lift pumps.



Anyone have any leads on what the heavy diesel industry, farm equipment or marine industry use?



I've been thinking about what Evan said. Can the solution be as simple as reloacting the pump and enlarging the fuel lines?? Maybe the solution has been right in front of us and we just have not realized it's as simple as Bombing the fuel lines.
 
Crazy Question

Ok,

I have a crazy question. I know the old 12v diesels had a mechianical fuel pump that seemed to be bulletprooof. Is there a way for the 24 v engines folks to convert to a mechinial fuel pump?:) :) :) :)
 
Call Schields, they can do this for you for about 4,000 i think. It's a lump in the cam that drives this pump off the 12v.



Andrew
 
I have taken 2 failed lift pumps apart and in both cases the pump was good, the motor was good but the shaft coulper was broken !!!!!!!:mad:
 
Re: Crazy Question

Originally posted by phumerick

Ok,

I have a crazy question. I know the old 12v diesels had a mechianical fuel pump that seemed to be bulletprooof. Is there a way for the 24 v engines folks to convert to a mechinial fuel pump?:) :) :) :)



The VP44 is a mechanical injection pump with electrical control for injection timing and fuel quantity. The engine mechanically rotates the VP44, it is also two pumps in one. One pump draws the fuel in and one pressurizes it to around 14,500 psi. The VP44 was not designed to need a lift pump. I guess the lift pump is there to make life easier on the VP44 and make it easier to get the truck running when you open up the fuel system to change the fuel filter? It also protects agains't warranty claims on marginal VP44's, helping them make it past the old 5 year 100K mile DC get out of jail free card/warranty :D I think you might be better off to run on a dead lift pump early in the warranty cycle to make sure you have a good VP44, then to have it changed out anytime it shows marginal reading. I would want to know early on if I have a good VP44, unless your going to trade before the warranty is up.
 
Originally posted by TxDieselKid

Call Schields, they can do this for you for about 4,000 i think. It's a lump in the cam that drives this pump off the 12v.



Andrew



I talked to Rod at Wildcat Diesel Performance about converting to the 12V mechanical lift pump. The mount for the mechanical lift pump is still on the blocks, just covered with a plate. Problem is the 24V cam is missing the lobe to drive a mechanical lift pump and a 12V cam won't work in a 24V engine. I was told to have a custom cam made for a 24V with the extra lobe to drive the mechanical lift pump runs around $3K JUST FOR THE CAM!! So $4K for the whole conversion is probably about right. I know there has to be a more affordable option.



Shooter:



Good info to know. Thick others have mentioned they have found the cause of low pressures a result of the pressure regulator (??) spring weakening and therefore adequate fuel pressures and flow rates are not obtained. Maybe we need to design a "Bomb kit" which replaces all the "guts" of the OEM lift pumps. I know there are TDR members with the ingenuity to fabricate stronger and better internal componets for these lift pumps. How about it, any takers on designing a new and improved billet lift pump? If I had the know how and tools/machines I'd give it a try.
 
Yeah they did a "kit" kinda for some Hummers that wanted the best of both worlds from what I understand. I think it was around $4,000. Just for fun, I hear that the DD cam has the lobe to drive the mechanel pump on the 24v's too. :D



Andrew
 
I am seriously looking at the pump setup CannonBall is trying on his truck, along with the regulator.



Here is the Holley link to the pump he is using. Pump #512-103.



It pumps 50 GPH continiously, and has been tested up to 2500 hours. Since the mighty Cummins will not use more than 10-15 gallons per hour at WOT, this is more than enough fuel.



I'm going to call Holley tomorrow for the low-down on the pump.



I think we are overworking the high volume pumps (100+ GPH) we have been trying, Mallory, BG, etc. with our restricted system.
 
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I tried to send an e-mail to Holly one time to ask them some questions and the reply I got was along these lines... .



"NONE of our pumps are compadible with diesel. "



I should have wrote back and said, "Want to bet?"



Andrew
 
I like this 2500 hour part, but where did this number come from?

Bench tested for 2500 with Gas running through it or 2500 on a CTD with Diesel running through it?



I need to know, its time to pull the old stock (dying) one off before I start towing again this spring!



Originally posted by BIG BOB



It pumps 50 GPH continiously, and has been tested up to 2500 hours. .
 
Ray T is a machineist maybe he could design a coupler out of stainless or some thing.

I just disassembled 2 of my 4 dead pumps and as Shooter stated its the coupler that has let go. All other internal parts look fine.

TJ
 
TowPro,



The 2500 hours comes from the Holley website. (click the blue link)



I called Holley today, they said like TxDieselKid stated, "None of our pump are compatiable with diesel, No warranty".



So now what do we do? :(



I also talked with Carter today, their recommendation was their P4601HP pump with their 404-501 regulator, with 1 year warranty.



I want to try a pump under 100 GPH, just to compare the longivity.



I also called Aeromotive today, they recommended their "Street Rod Pump #11203". However, they said their was no warranty with diesel.



Anyone got any ideas?
 
pumps

big bob, first, be careful about going to a lower volume pump. i tried a low volume (30 GPH at 7PSI) as a pusher. ran the pump for about 4 K miles as a pusher to the carter BEFORE i got my gauges in. (i know, DUMB!!!). i took it off very quickly after the gauges went in. pressures at idle were 20-21, and 14 at cruise. great numbers right?? NOT!! WFO (WOT) pressure went to 0 PSI, and stayed there!!!! this is on a stock truck with no enhancements.

second, i have gotten info on Borg-Warner electric pumps. BWD number EP4600P is a 7 PSI 100 GPH pump. diesel is listed as OK, and guarantee is "limited lifetime". BWD EP4601P is a 15 PSI 100 GPH pump. again, "limited lifetime" warranty. i will probably try a 4600 as a pusher at sometime in the future. right now, i'm watching my carter--pressures are slowly dropping, and WFO pressure is 4-5 PSI. if mine weren't to be replaced under warranty, i'd try the 4601. it may just be a carter (numbers the same???), but they give you a good warranty, if my info is correct.
 
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