leathermaneod

I emailed Richard at Glacier, he replied very quickly as usual :-) he said it is merely a warning code and does not affect engine operation in any way.

KATOOM

Too bad there isnt any type of dummy plug connector which would fool the ECM into thinking the fuel pump is still there.

leathermaneod

Yeah that would be pretty sweet. I'm not too good with electronics but my limited understanding suggests that all you would need is the correct resistor....invention idea for someone more talented than myself? Then again if it doesn't hurt anything why mess with it lol...I see where your coming from though...if it caused a CEL I would be really annoyed but since it's nothing like that it's not too big of a deal to me. It would be cool if Glacier would include one with the kit though

leathermaneod

So here's another small dilemma for you gents to hopefully help me solve. I am trying to get my fuel pressure dialed in exactly where it should be with the Fuel Boss and the bypass valve tuning kit. Problem is, now that I have a second fp gauge to verify, I get two different readings, my in cab, mechanical autometer reads about 13.5 at startup, and then once warm around 14 at idle, up to about 16 with normal driving and not much higher at wot. My Vulcan test gauge reads 1.5-2 psi higher. Now the pressure has also climbed a little as the 24 micron ff5079 inline strainer has started to get restriced (apparently I have a very dirty fuel tank). I'm thinking about switching out that 5079 for a napa 3270 which is a similar strainer but is 124 micron, and seeing if that will still clean everything sufficiently to ensure proper operation of the bypass valve. That will probably lower my fuel pressure a pound or so. With all that said, should I try to increase it just a bit so that it is for sure never ever below 15 psi? With the volume the the Fuel Boss pushes, does it even matter is its a little below 15? Even with the mechanical nature of the Fuel Boss, pressure does dip momentarily when you increase the demand for fuel and the turbo spools (1-2 psi) before climbing back up with the rpms. I was reading a very informative post on the Cummins forum that suggested the overflow pressure doesn't even corellate to inlet pressure but rather is determined by the vp's internal came pump.

Now some will doubtless read this and think why not just turn it way up if it's that easy? Well my issues with that is that I don't want it going too high because it increases with rpms. I am afraid of ending up in the 20-25 psi range and I don't know if that's something to be concerned about. I am also concerned about putting too much pressure on the vp during cranking as I know the FB builds pressure pretty quickly and I don't know if I could harm the vp or cause a hard start by increasing the pressure. I don't know for sure if pressure comes up quick enough for that or not. Basically I'm trying to see if you guys think I'm safe where I'm at or if I'd be safer increasing by a pound or two?

Also, I asked this in a related thread on the Cummins forum but I'll ask it here too for the benefit of anyone following this. I am running the $8 snubber from Geno's on a tapped 90° on the outlet side of my stock ff housing. Plumbing goes tapped 90°, street 90° because I ran out of room, snubber, npt to jic converter, Vulcan universal fuel line, to isolator, to autometer mechanical gauge. Some comments on the other forums had me wondering if I should be using a second snubber or a needle valve in there as well? Another reason I ask is because I do have a slight gauge bounce, about 1-2 psi and fairly steady, only notice at idle though. Not sure if that could be caused by the dynamic pulses or not? I don't think it bounces fast enough for that but I'm certainly no expert!

Thanks again as always! I sure hope you guys enjoy all this as much as I do lol I love learning about these trucks!

Ps my truck has been running and starting very well this past week. I think part of the problem before was that I was expecting a little too much. I've finally been able to put some miles on it and use up the life of the 15w-40 Rotella that's in it so I can make the switch to Valvoline Premium Blue Extreme 5w-40!

KATOOM

I try to highlight the key points which you mention, so let me know if I'm not fully addressing everything.....

You are NEVER going to get two different gauges to read exactly the same. Well maybe if they're multi-million dollar equipment gauges but anything we pay $50-$100 for isnt going to be "perfect". So if you're getting a variance of 2 psi then just split the difference and assume neither is right. Thats about as good as you're going to get.

Changing out strainers until you get one that allows enough dirt to pass.....but not plug the valve doesnt make sense to me. You obviously have a dirty fuel tank issue so instead of spending more money and tearing apart the fuel system again, just drop the tank and clean it. Then make sure you buy from reputable stations who move a decent volume of diesel so you can lower your chances of picking up storage tank dirt.

I cant fully comment with absolute assertion that you should NEVER let your fuel pressure drop below 15 psi. There's a lot of information behind that subject and I could be typing for days trying to share what data I've collected and understand about this over the past decade or so. But just know that I prefer to maintain no less that 15 psi on my truck. And because I have an electric pump which drops pressure with demand and RPM, I have my idle pressure set around 20(ish) to offset the overall drop to about 16-17 psi.

My "high precision" ISSPRO mechanical gauge tells me that over the past couple years my pressure has settled at around 22-23 psi at idle and my Vulcan test gauge states within 2 psi of that. I dont fret the high pressure either because 1) there is no reported case of someone damaging the VP from running excessive fuel pressures, and 2) there is nothing I've heard of which can fail as a result of that pressure. The transfer pump feeds the low pressure chamber whereby the vane pump take that and pressurizes it to around 300 psi. The vane pump isnt sealed off either so whats to fail? You'll hear that it can affect the diaphragm but its important to understand that the diaphragm is no longer plastic but rather metal over thick plastic, and the diaphragm is what separates the vane from the rotor/distributor. So if the vane pumps out 300 psi then how can 25 psi from my supply pump do anything? Lots of unknowns about the VP out there.....

In saying all that, dont forget that you'll see varying pressure differences from the cold winter fuel and hot summer fuel which can generally be a couple psi either way.

As for cranking pressures and starting issues, well thats not a problem for a cold engine but it will affect a hot one simply because what "can" happen is the timing ring in the VP is positioned by the timing solenoid. During engine cranking that timing ring is in the full retarded position. Its thought that as the temperature of the VP rises, and also as it heat soaks from the hotter engine temp, then the timing ring can become too tight for the solenoid to move while there's excessive incoming cranking pressures. As the engine cranks the VP shaft turns and the fuel pressure against the timing solenoid purges, therefore allowing the ring to move, thus the extra cranking. I know thats all sounding confusing since there's three pressure chambers in the VP so how can the lowest one ever affect the highest one.....but just know that it does.

I cant imagine how your Fuel Boss could take ZERO fuel pressure and pump it fast enough while cranking to ever cause a hard hot start.....but if it does then it does. Remember.....ONLY a HOT engine starting issue, not a COLD engine. Lastly, no one can positively state whether or not the overflow valves output has any correlation to supply pump pressure. People make that claim but I dont think I've seen anyone confirm this by isolating the overflows output line from the injector overflow line and determining the volume based on supply pressures. But thats not me trying to state I'm right and everyone else is wrong but more than for those to state "facts" without positively knowing isnt fair to the rest of us. No matter, at this stage in the game its more an understanding that since the OEM Carter fuel pumps were regulated at 15 psi then it would seem coincidental that the overflow valve is set wide open at 14-16 psi. Whether or not there is a correlation..... Cant say inequitably.

Fuel pressure pulses can cause gauge needle bouncing but if you have a snubber in place then thats your best defense. I couldnt really make out your pluming description either so maybe I'm not fully understanding how you have it set up. Also, if your gauge is bouncing from dynamic fluid pulses then it would bounce the most at idle since thats your lowest pressure generated. If its bouncing around while driving then I may assume that your Fuel Boss pressure regulator is not regulating very smoothly. But nonetheless, there's nothing wrong with two snubbers in the FP gauge line. I have a dedicated snubber and a snubbing orifice on the gauge itself for smoother action. But thats just my liking's.

Oh and I'm going to tell you to save your money by NOT spending it on synthetic Valvoline 5-40 since I was under the impression you dont live where the ambient temps get low enough to justify that added expense. I run Valvoline 15-40 and the winter around here can sometimes dip in the high 20's at night. I know you're trying to do the best for your truck but I'd hate to see you throw money away on high dollar synthetic engine oil. Now if you wanted to run synthetic rear differential fluid then I'd say thats a wise choice.

leathermaneod

Well it is reassuring to hear you are in the same boat with slight inconsistencies between gauges. I was really kind of annoyed at my Autometer for being inaccurate lol And I know I need to drop and clean my tank but the snow is starting to fly and its getting cold and I have no indoor place to work lol. I may get to it over Christmas but I'm not sure.

As for the pressure, it sounds like I should just bump it up a bit for peace of mind if nothing else. Especially now that I know there is no reason to think pressure over 20 psi will hurt anything. I really wish we knew more about the vp44. Its really a pretty awesome machine, but its crazy that its been around for so long and we still don't have all the answers. I watched the video about it in the vp44 sticky on the cummins forum. I thought it was really interesting how they made no mention of the diaphragm. I agree that it would be quite a coincidence for the carter pump to be regulated at 15 psi just like the overflow valve, but I wonder if that was merely Chrysler engineers not understanding the vp44. Because if the vane pump generates 300 psi in the same chamber that the inlet is connected to, how could the inlet pressure affect the overflow? Please don't misunderstand, I'm in no way trying to argue with you. I'm just talking and trying to learn from your experience and research.

Thanks for explaining about the vp and timing! It is a little confusing, but its coming together somewhat. And I think you are probably right about the Fuel Boss not generating pressure quickly enough to be a starting issue. On top of that I think someone else would have figured it out by now too.

I posted a picture of my plumbing with the parts labeled in my gallery if you are interested. Its a little crud because I did it on my phone but i think it will make sense when you see it. Im not sure if the gauge bouncing is due to the pulses or not. It is only at idle, but I would think it would be a lot faster if it were from the pulses, I was under the impression that they would be generated extremely quickly. Oh well, no big deal. Hopefully it doesn't hurt the gauge. Maybe eventually Ill add a needle valve in there too. I don't really feel like breaking it open and risking more leaks right now though lol.

Thanks for the tip on the syn oil, but I decided to go with it after much research because where I live it is not uncommon to see temps not get over 0 for weeks at a time in the middle of winter. And unfortunately, where I work there is no place to plug in. I will always at home and already have been, but I won't be able to at work. Thats another reason I was trying so hard to ensure my starting was tip top. I am running Valvoline Synpower 75-140 in front and rear diffs :-)

KATOOM

No problem and glad I can help at all.....

If you can get by until the weather is more comfortable then why not wait it out. No need to freeze for something thats not harming anything or causing any issues. Not that dropping the tank it terribly hard but its so much nicer to be comfortable.

And Chrysler didnt supply the lift pump, but rather Cummins supplied a complete engine to Dodge. Actually its been said that they (Dodge and Cummins) knew that a fuel pump separate from the engine was better but having the engines complete was part of the deal.

Also, dont misunderstand what I was trying to explain.....even though I'm sure I botched it up some, but what I meant to describe was that the supply pump pressurizes the low pressure chamber at 15 psi, then the vane pump takes that fuel and pressurizes it inside the mid pressure chamber. There is a pressure regulator in the low pressure side too.

So no, the vane pump isnt "pressuring" the low pressure chamber but rather that as long as the VP shaft is spinning, the vane is sending that pressure onward to the accumulator. My only point was that there is no seal separation between the supply pressure and the vane.

You're picture of the fuel system helps but I'm a little confused about the street L. There's a 90* coming out the bottom of the fuel filter housing but where's the street L? And why?

leathermaneod

Very interesting! If they wanted a complete unit I wonder why they didnt use the same lift pump from the 12v...I believe the block is the same anyway isn't it? That sure would have changed history huh? Thanks for clearing that stuff up thought :-)

The street L is like a smaller version of the 90 off the ff housing. It just makes it so that the gauge line is going in the same direction as the vp supply line when it comes out of the tapped 90. There was not enough room between that tapped 90 and the motor mount to go straight down with the snubber and gauge line so the Street L was needed to make the turn. Sorry if that is still confusing. If I'm still not making sense ill take a better picture in 2 weeks when I get home from leave

By the way I'm going to start a thread about doing a VE swap into a 24v if you wanna jump in on that haha

jrs_dodge_diesel

The mechanical pump off of the 12V puts out pressure around 17-22 PSI at idle, and goes up with RPM to around 35-45 at 2500 RPM. So a lift pump off a 12 valve won't work on a 24 valve as a bolt on replacement without modification.

The block is the mostly the same. The location on the block for the 12 valve lift pump is where our electric lift pumps are mounted. The mount for our pumps also serves as a block off plate for the hole in the block for the 12V pump, since they were camshaft driven pumps. And you can't put a 12 valve lift pump on our 24 valve engines without two things, a pressure regulator to bring the pressure down, and a new camshaft. The 12V camshafts have a 13th lobe for driving it's lift pump, stock 24V camshafts only have 12 cam lobes.

KATOOM

There you have it.....and well said too.

As for the VE, I'm not sure that would be worth the effort. The VE wasnt anything great and if you're going to swap out the VP for anything it would make sense to use a P-pump. But.....as popular as some think that swap is, I feel its important to make people aware that if you live in a state that is currently smogging diesels or will be in the future, you'll most likely have a problem since by swapping injection pumps you've altered the engine. How the emission laws are effected by that swap would also be important to know too. In California, even though the 2nd gen 24 valve trucks have zero emission components, you're still not allowed to alter the engine or its performance output. So that means a P-pumped or VE swap 24 valve would fail smog around these parts of the country. Sad but still a variable we have to deal with.

jrs_dodge_diesel

Thanks KATOOM

I think some of the reasons the VE pump swap gets attention is the (somewhat) relative ease in swap process. The injector lines are already in the right order and locations, only need extended adapters (VE is a little shorter than a VP). The VE does require a new timing case due to the way it mounts. The injectors would need to be taken out and adjusted for the lower pop pressures of the VE

The VE do have some neat advantages: Fast start ups, hot or cold. Timing is adjustable by hand. The engine runs smoother compared to a P7100 pump. And lastly, the VE pump is easily rebuildable by anyone with decent mechanical skills, something that could not be done with the VP44.

And yes, CA has some very silly regulations.

leathermaneod

you nailed it jrs :-) that is my reasoning in a nutshell. I think the only thing you really left out is the relative low cost compared to a P7100. From what I've heard, you can swap to a VE for about the same price as a new VP. As long as your doing the work yourself, and I wouldn't trust anyone to do something like this haha. I also am a big fan of the quick starts, and I've heard the VE is one of the more efficient of the Bosch pumps, if not the most efficient. I also do not and will not ever need/want the mega power you can make with the P pump, the VE will always be fine for me. I'm not totally sold on the VE, and I may never even get to do the swap, its just something I would like to learn more about and hopefully do in the future, and it seems like a more practical solution than a p pump to me. Thanks for the tip on the emissions thing too! I hadn't thought of that. It shouldn't ever effect me though because PA does not require emissions on older diesels.

BTW- Thanks for schooling me up on the 12v setup jrs! I love learning all the ins and outs of these engines :-)

leathermaneod

Here's another question for you guys. I guess maybe I should start a new thread for this stuff but it makes for a good chronicle of everything I'm doing to my truck lol.

Anyway, I'm making a plan for what all I want to accomplish when I drop my fuel tank to clean it. I'm hoping to do it in my father-in-law's shop while home for Christmas. So I have to plan well and make sure I have all the parts I need. I would like to upgrade the factory return line to rubber, all the way from the return "T" to the tank and run it through the frame with my new supply lines for one. Does it matter what size I use? I believe the stock one is 5/16. Should I upgrade the fuel basket at all? I ask because I am concerned it may start to fail and suck air just because its old. I was going to use a Vulcan DrawStraw I, so that I could have the suction line, return line, and Fuel Boss return all in one place. Unfortunately, after asking Richard at Glacier, I learned that for some reason the DrawStraw does not work with the Fuel Boss. Richard told me he had two other customers that tried it and had major low pressure issues and Vulcan was not able to tell them why. I asked Richard about just using the supply and 1 return port on the Vulcan DrawStraw and still returning the Fuel Boss to the filler neck, but he said he couldn't say for sure after that bad experience. So thats out. He said he strongly recommended just continuing to use the factory setup if it doesn't have anything wrong with it. My only concerns are like I said that the factory unit will fail due to age soon after I clean the tank, and I would like to eliminate restriction. What do you guys think? Maybe a Fass Draw straw or a sump? Or just keep it stock with the removal of the screen if it looks ok?

KATOOM

I have no problems with you asking questions on this thread but just know that the only people following who may have input for you are the few who've pitched in so far. Meaning, if you want more well rounded responses to particular inquiries then by all means start another thread. But that said, you can still ask here as well as in a new thread if you actually care for my long winded answers. I'm not on the forum very often looking for new threads so I may not catch whatever new thread you start until later on.

As for dropping the tank and the return line and the module..... Dropping the tank is easy. The OEM fuel module is perfectly fine using too as long as the pre-screen isnt damaged allowing debris to be sucked up. From all the garbage in your line it does kinda sound like it may be though. I would highly suggest NOT removing the screen and if it is damaged then replace the module.

The return and the supply are next to each other, in the same module basket, which is how the engine gets fuel when the tank level gets low. The basket plays as a small reserve.
Drawstraws are stand alone supply inlets and you install them somewhere else in the tank, which means the only fuel available is the fuel it can suck up is whatever is passing by at the bottom of the tank. And the depth of the drawstraw when installed is easily done incorrectly too. Addressing the install issue further, the distance from the bottom to the top of the tank varies depending on how much fuel is in there too which further skews installation. These are all reasons why drawstraws are so problematic with low fuel levels. So really, I wouldn't use a drawstraw unless I had too. Even at that, I would use one of the aftermarket fuel modules first before I tried a drawstraw. Even with the 5/16" quick connect fitting, you need a lot of fueling to justify eliminating the fuel module. Again.....dont mess with whats working. The likelihood of the fuel module allowing air to enter the fuel lines too is almost impossible since the only way this could potentially happen is if the supply line quick connect fitting o-ring was damaged.

I'm sure the problem Fuel Boss system has with drawstaws is the fact that FB also returns via the fuel tank fill hose. The OEM fuel module works so well is because of the basket whereby the drawstraw probably aerates the supply line too much as it gulps passing fuel which may cause cavitation in the FB, reducing pressure. Not completely sure but it sounds likely.

The sumps are pretty cool but not only do you have to cut a hole in the bottom of the tank and re-route your lines underneath but I have no idea if they offer any type or level of pre-filtration like the fuel module does. Probably not so you'll quickly find yourself back to square one if you happen to get any crud in the tank again. And I thought this whole "dropping the tank" effort was to get rid of the junk in the tank in the first place which is making its way up the fuel line.

And no, dont change the return line to rubber. Waste of time as the hard metal 5/16" line is perfectly fine handling the volume running through it. Others have gone through the trouble and found no gain. And why create a reason to have to find a way to run a new fuel line which is already nicely tucked up along the frame rail? Plus you'll have to also change all the fuel line fittings affected by that change or find a way to get fittings that can connect to whats already pre-fitted on the return line ends. Seems like a pain in the rear.

leathermaneod

I actually enjoy ready your "long winded" replies lol I prefer talking with someone who takes the time to explain things.

As far as the stock fuel basket and the screen goes, what is the advantage of having that screen? I mean obviously it filters out some dirt but isn't there a risk of it getting clogged and causing the pump to cavitate? And if you had a DrawStraw you would t have any type of screen...Also what does pump cavitation mean exactly? I know it's not a good thing but what exactly does it mean? And if I have to replace the module, do you know a good source for a new one?

Thank you for taking the time to explain all that about draw straws as well. With all the hype I thought they were the cats meow! I also appreciate you explaining about the fuel boss and why it wouldn't work with a draw straw.

What you said about replacing the return line makes sense too. I'll leave it as well as long as it's in good shape.

Yes the sumps are cool but I wouldn't like the fuel line outside on the bottom of the tank. The only one I like is the FASS that has a suction tube inside the tank but still feeds from the sump. But it doesn't have any type of screen like you mentioned.