Welcome to the Dodge Cummins Diesel Forum, the fastest growing Dodge Diesel Community on the internet.
You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!
If you have any problems with the registration process or your account login, please contact contact us
98.5-02 PowertrainDiscussion of components that are directly involved in the power production and all that is needed to get and keep the truck moving . Engine , Transmission Ect..NO ADVERTISING .
I HATE TO DO THIS - FUEL TRANSFER PUMPS REVISITED
(or The Final Answer - Perfect Transfer Pump Article)
As the deadline for Issue 56 was fast approaching, I called TDR writer Jim Anderson. Jim is the point guy for miscellaneous e-mail and phone inquiries that come into the TDR. I asked, “Hey Jim, what’s on the minds of those that you are corresponding with?” His response, “It seems that problems with the Third Generation trucks vary. There is not a common complaint that needs to be addressed.” This is good news for the Third Generation crowd.
Jim continued, “However, with the used truck purchase of ’98.5-'02 vehicles the education about fuel transfer pumps is an endless task.” I responded, “Ouch, I know what you mean. Perhaps I should emulate the country music singer David Allen Coe’s efforts to write the perfect country music song by writing the perfect transfer pump article.” Jim responded, “Keep it simple, try the catch phrase from the Millionaire show ‘Is that your final answer?’”
Thus, I present the final-answer, perfect transfer pump article. While the article focuses on the '98.5-'02 owners, this collection of TDR oldies also has tips for '94-'98 12-valve owners and '03-'07 HPCR owners. The information was pulled from our Issue 32, 48, and 50 magazines. Updates have been added to reflect the latest part number information.
Then, to add a final crescendo to the article, I’ll share with you a story that will be of interest to 300,000+ owners of '03 and '04.5 HPCR owners.
Below is an outline of the topics that will be covered.
• ’98.5-’02 trucks, correct fuel pressure
• ‘94-’98 12-valve, fuel transfer pump replacement
• ‘98.5-’02 24-valve, fuel transfer pump replacement
• Fuel pressure gauges and opinions
• ‘98.5-’02 24-valve, fuel transfer pump relocation kit
• ‘98.5-’02 24-valve, what to do
• ‘03-’04.5 HPCR, what to do
• ‘05 to current HPCR, what to do
Here we go…
CORRECT FUEL PRESSURE— ‘98.5-’02 TRUCKS
by Robert Patton and Jim Anderson
In May of 2001 there was a great deal of concern about fuel transfer pump delivery pressures. The problem first surfaced as a result of a production batch of inadequate transfer pumps and the resulting product recall. Hand-in-hand with the recall was the increasing number of warranty claims. (When the article was written the early '98.5 engines were 2.5 years old.) The problems were aggravated by those that hot-rod their trucks as well as purchase fuel system accessories that add restriction to the system. The bottom line is that the 24-valve’s Bosch VP44 electronic fuel delivery pump needs to see at least 5-6psi of pressure from the fuel transfer pump. Less than 5-6psi (more is better) and there is a danger of “overheating” the VP44 pump for it uses fuel to cool and lubricate its internal parts.
In the photo, note that the Editor’s truck (a '99 model) is outfitted
with two gauges—one is a mechanical, liquid-filled gauge
and the other is a Westach electrical gauge with a pressure
sending-unit mounted to the filter head assembly.
In order to install a gauge, the ’98 and ’99 24-valve engines have a filter head with easily accessible 1/8 NPT fittings. On the 2000 and up trucks the service design team at Cummins was mindful of the need to test the fuel transfer pump’s delivery pressure. Thus, your truck is equipped with a “banjo adapter with a Schrader valve assembly.” Say what? For clarification let’s look at a photo and a description.
On the inside, the part with the rifled opening attaches the fuel line to the fuel pump. On the outside, the Schrader valve (think A/C valve or, better yet, a tire valve) has a press-for-pressure needle. Here is the catch, you can take the pressure needle out of the Schrader valve.
What Pressure Should I See?
In order to install a gauge, the ’98 and ’99 24-valve engines have a filter head with easily accessible 1/8 NPT fittings. On the 2000 and up trucks the service design team at Cummins was mindful of the need to test the fuel transfer pump’s delivery pressure. Thus, your truck is equipped with a “banjo adapter with a Schrader valve assembly.” Say what? For clarification let’s look at a photo and a description.
The readings that I am seeing on the gauge:
13-14 psi at idle
12 psi @ 2000 rpm – no load
11 psi @ 3000 rpm – no load
10 psi @ 3500 rpm – no load
10 psi @ various rpm – 10 psi boost
8 psi @ various rpm – 20 psi boost
3 psi @ various rpm – 30 psi boost*
*From the readings at idle and at various rpm with a load (and a resulting boost reading that is at stock truck/20 psi or below levels), the gauge checks out okay. As I push the performance envelope with my hot-rodded engine (i.e. the 30 psi boost reading), the fuel pump is marginal.
Does the fuel pump meet the stock specifications? Yes. Is it ideal for my truck’s hot-rodded performance? Good question. In discussions with other hot-rod owners I find that the old adage, “I am my own warranty station” once again proves correct. As you increase the output power of the engine from its design, the hotrodder has to look at upgrading other components. Discussions with other owners have uncovered various solutions to the low pressure at high performance blues: drilled out banjo bolts for better fuel flow, bigger fuel lines, different fuel pumps, different pump locations. The saga will continue.
This is not a write up from me. This comes from the website. Just thought I put it up here.
bottom line.... and anyone can argue it if they want, but when your vp blows up, dont get upset about..... cummins spec is the vp44 must have no less than 10psi any time the motor is running, and 7psi while cranking. On my truck, i expect to see no less than 15psi when the truck is running.
__________________
01' 3500 4x4: Custom Valair II, SO, fully ported/polished CR head with my intake manifold. 1.6's , 63/68/14 http://valairinc.com/
working on "Toby"
Check out bold type, and Just FYI my VP44 did blow up 84,000 miles ago while running YOUR 15 PSI reading. Now I run 7-12 psi with 84,000 miles on new VP44 and Intank pump, with NO problems to date.
BOSCH VP44 INJECTION PUMP AND LIFT PUMP FAILURES EXPLAINED
The best way to start this explanation is to quote an e-mail that was found on the Cummins website. “The Bosch VP44 has not been as reliable as we had hoped”. Depending on who you talk to and who you think is being honest, you will most likely get only some of the information you need. I will endeavor here fill in the gaps and get you up to date and informed; the reason I can tell you more is because Bosch had not, until 2004, allowed any franchised dealer to do anything except to send defective pumps back to the remanufacturing facility. Long before that Blue Chip had dismantled many pumps to figure them out and diagnose what failed and what caused the failure. We do not pretend to be any where near as smart as Bosch, but since there was no experience or information or truth out there, we felt we had to get the best information we could any way possible. Probably the most informative source were the applications for the patents applicable to the VP44. It was this dismantling and learning process that allowed us to get a patent and a performance product to market first.
The most common MECHANICAL failure with the VP44 pump is the cause of the code 216. This is when weak lift pumps with low fuel pressure over a perioid of time rupture the diaphragm in the front of the injection pump and the timing piston then vibrates and wears the housing of the pump until fuel bypasses the piston and full advance can no longer be attained. When full advance can't be attained for more than 5 seconds the code 216 is set. This means your pump has lost a lot of its power and fuel mileage and needs to be replaced and upgraded.
The next most common MECHANICAL failure is that the rotor seizes in the distributor section of the pump. I should note here that all previous rotary style pumps have had this problem too, to varying degrees. The most common cause and most accepted reason for this failure on rotary pumps is lack of lubrication due to running out of fuel or the possible lower lubricity of the newer low sulphur fuels.
In the case of the VP44 it is more common for the rotor to seize in the distributor because the pressures are MUCH higher and therefore mechanical tolerances have to be much smaller. Add the fact that the rotor was not "deburred" enough or correctly during manufacture, and these failures can be easily explained. Under the higher working pressure in the VP44, the edge of the slot in the rotor deflects and interferes with the distributor. Sooner or later the result is a galling of the two parts and then binding and then seizure. The seizure causes the "Drive Plate" to break and the truck stops running, never to start again until the VP44 is replaced. There is less than a half a thousanth of an inch clearance between the two parts, so it doesn't take much to make the rotor interfere with the rotor. Pumps made recently (since about 2000) are experiencing fewer of these kinds of failures, it seems to me.
The other reason injection pumps fail is ELECTRCAL issues and failures. These are the problems that cause 99% of the drivability problems. The computer on the top of the VP44 is susceptible to heat and many many heat cycles. The components on the circuit board develop bad connections due to crystallized solder over time and the result is intermittent hard start, white smoke and drivability issues such as the common " Dead Pedal". Rarely can these issues be verified or diagnosed by codes set in the ECM.
A lot of people have heard about bad lift pumps and think they are the cause of VP44 drivability issues and therefore electrical failures; NOT SO! Starting with the early 98’s, not only were they weak pressure wise, but also had exposed terminals on the bottom that corrode off in salt environments. The way to tell if you have a corrosion sensitive pump is to see if the electrical connection is a plug on a 6-inch pigtail coming from the bottom of the pump. If the plug is on the top cover of the pump you’re all set, for that problem anyway!
If the lift pump is not delivering fuel pressure the truck stays running because there is a gear pump in the front of the injection pump, which keeps the fuel flowing, albeit at a much lower pressure than desired, and hopefully maintains lubrication to the rotor. As long as there is return fuel flow from the injection pump there is lubrication to the rotor, so low fuel pressure and certainly less return fuel makes it much easier to starve the rotor for lubrication. The only accurate way to test a lift pump is to monitor pressure UNDER LOAD and if it is above 5 PSI, no performance is lost and the pump is OK. If pressure is less than this, a modest reduction in horsepower results. The usual scenerio is a customer puts a performance box on his truck and the lift pump can't produce enough fuel to make more horsepower, and the performance product gets the blame.This sympton is most always a "Buck" as opposed to a "Surge" under load.
Often people have mistakenly said that increased pressure from add-on performance devices causes the injection pump failures. This statement only indicates their lack of knowledge, because, unlike most pumps, the VP44 pump does not create more fuel delivery by increasing lift pump pressure. The VP44 creates more fuel delivery by holding the fuel bypass solenoid closed longer. Fuel delivery pressure is controlled by the “pop off pressure “ of the injector.
The reason any aftermarket device that hooks up to the solenoid wire is blamed for the failure is that the failure 99 times out of 100 (honest numbers here) the pump fails within 20 minutes of installing and running with power enhancement. The reason this happens is because the fuel solenoid is held closed longer, therefore using more length of the slot in the rotor. The slot in the rotor overlaps a hole in the distributor to allow for different timing and amounts of fuel to be delivered to the injector and when the solenoid holds the bypass solenoid closed longer, then the high “pop off” pressure is still there when the middle of the slot overlaps the hole. The middle of the slot is the weakest area and therefore deflects, interferes with the distributor and seizes. Pump failure with fuel enhancement devices is not CAUSED by the enhancement device, but PRECIPITATED by the device. WE think this is a “glass half full” scenario rather than a “glass half empty” one, because the potential, eventual failure can be determined within controllable parameters, namely on the test run at higher power, close to home or the local dealer. The other side of the coin is, honestly, if your truck is still running 20 minutes after the installation AND BEAT RUN, you have a 90% chance your pump will not fail for a mechanical reason and therefore last until electrical issues start to show.
Lastly the installation of bigger injectors; do they alleviate the high pressure or raise the pop off pressure and therefore cause many failures of the VP44? Absolutely NOT. They are a bigger hole so fuel volume is increased at the same pressure. Remember fuel pressure is controlled by “Pop off” pressure more than the size of the hole! Aftermarket injectors that DO raise the pop off pressure do not appear to cause any problems. Bigger injectors do get more fuel into the combustion chamber sooner, therefore giving the engine better throttle response.Bigger injectors are worth it but not for the reason of saving the pump.
Thanks for reading, Chip Fisher, owner of Blue Chip Diesel Performance
If your truck "Bucks" under hard load or towing this is an indication the engine is probably starving for fuel, due to low lift pump pressure. To test fuel pressure, install a fuel pressure gauge with a long hose on it after the fuel filter and before the injection pump. The long hose allows you to drive the truck and watch the gauge at the same time! Or..........if this is inconvenient for you come by, you can install our “Low Fuel Pressure Warning Kit” and it will diagnose low fuel pressure too.
To diagnose lift pump performance click the ignition key to the start function quickly, so the engine doesn't start, and let go, leaving the key in the run position; the lift pump should run 25 seconds. If you don't hear the lift pump, check fuse number 9 in the fusebox on the left side of the dash, and if that is good, test for 12 volts going into the lift pump and if it doesn't run with 12 volts going into it, replace it. If you do hear it run and it doesn't make at least 5 PSI replace the fuel filter. If, after changing the filter, it DOES make at least 5 PSI go DRIVE the truck UNDER LOAD. If it doesn't make at least 5 PSI UNDER LOAD after changing the filter, or if you have to pressurize the fuel tank to bleed the system to get the truck to run, then change the lift pump.
Please realize that revving it up proves NOTHING. If DRIVING UNDER LOAD the pressure drops below 5 PSI, replace the fuel filter (if you haven't already done so) and if that doesn't fix it, I am 99% sure you need a new lift pump.
Another possible cause of low pressure is rusty fuel lines, sucking air. The way to test for air in the line is to replace a section of the fuel supply line with a clear polyethylene hose, between the lift pump and the injection pump, and run the engine to see if there are any bubbles, indicating air as the culprit. We proved on a dynomometer in 1998 that if you have 5 PSI, under load, you can make all the power available from a VP44, and 5 psi will provide plenty of return fuel for pump lubrication. We do not recommend running more than 12-15 PSI as that does NOT help the fuel system in any way. In fact higher pressures could diminish fuel delivery to the rotor and make the truck run worse at high RPM and possibly overheat and damage the fuel bypass solenoid.
This diagnosis is only for the lift pump, but is necessary for the successful diagnosis of possible injection pump issues. If you don’t have enough lift pump pressure it will ONLY cause low power or bucking under load. All other driveability issues are caused by the computer on the top of the injection pump, or by fuel contamination and stuck internal parts in the injection pump.
Replacement lift pumps that make more than 15 psi are in my mind overkill and not necessary. The FASS system is a dependable alternative and very popular, but not necessary. The "In Tank" unit sold exclusively by Dodge does NOT work as well as the old style on the side of the engine! Cummins still sells the exact replacement that mounts on the side of the engine and that is what we sell.
Thanks for reading, Chip Fisher, owner of Blue Chip Diesel
Blue Chip just proved my point that 5 psi is the lowest. They've done the testing and proved it.
it may have failed the test, but show me a failed VP44 because of it. Maybe YOU had a failed or bad pump, ever thought of that.
Your saying that TDR, Blue Chip, Rainier Dodge, and others are wrong.
My VP44 failed while running 15 PSI. Did you not get that.
10 psi is great, but the reality of it is this, many trucks are running the intank pump like me, and like me they are doing fine.
Example, 84,000 miles on less than 10 psi of fuel.
5 PSI is the lowest, CASE CLOSED. Don't like it, then Call Blue Chip performance. THEY TESTED IT AT 5 PSI AND PROVED, PROVED, THAT 5 PSI IS FINE. ANYTHING LESS, THEN YES ITS BAD. BUT 5 PSI IS THE LOWEST.
I'm now done with this, anything you write back on is worthless to me. because your wrong.
And on your link, 5 psi is written there. May not say much about it, but its there.
it may have failed the test, but show me a failed VP44 because of it. Maybe YOU had a failed or bad pump, ever thought of that.
Your saying that TDR, Blue Chip, Rainier Dodge, and others are wrong.
My VP44 failed while running 15 PSI. Did you not get that.
10 psi is great, but the reality of it is this, many trucks are running the intank pump like me, and like me they are doing fine.
Example, 84,000 miles on less than 10 psi of fuel.
5 PSI is the lowest, CASE CLOSED. Don't like it, then Call Blue Chip performance. THEY TESTED IT AT 5 PSI AND PROVED, PROVED, THAT 5 PSI IS FINE. ANYTHING LESS, THEN YES ITS BAD. BUT 5 PSI IS THE LOWEST.
I'm now done with this, anything you write back on is worthless to me. because your wrong.
And on your link, 5 psi is written there. May not say much about it, but its there.
Come back and talk to us after you start making some power and tell us how long your 5psi fed pump lasted you. And if you think 84000 miles on your pump is good, please tell me what you are smoking.
The case has been closed and until someone actually re-invents the VP44 it will stay closed 10-20psi period.
__________________
1999 2500 Quad Cab 4x4, Edge Juice w/Attitude, AirDog 100,II 62mm snail ,6" stack, BHAF, 125hp Injectors,5spd swap w/ Valair 3850 DD, thanks to Holland Court Diesel, and TheDityD! Jvmpmotorsports.com
replaced my VP44 2 years ago. that was the second pump to replace. REASON: fuel pressure too low. below 10 psi to be exact. had it tested. know it was true cause i wached the test and right after that shelled out $1800.00 to get the pump changed within 2 hrs of me showing up. truck works great and i bought a fuel gauge thursday. my $0.02 and money down the drain. do what you want to cause in the end it's your money.
__________________ Duke-2000 4x4 excab longbed, BHAF, billet converter, built valve body, heavy duty Eagle Red Alto/Kolene steels, Tunnel Ram intake plate, inline fuel filter kit from DAP, DTT's RASP lift pump, Dukie pipe intake horn, Griffin all Alum Radiator, 3rd gen chrome clads, Thuren control arms, Thuren 3rd Gen adjustable track bar, 08.5 steering, 35"x12.50" Toyo MT's
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.
Linear Mode
