Engine/Transmission (1998.5 - 2002) pumps, lines & whatnot

[AdamH]

I am interested in the sump to see what kind of sealer you come up with and what kind of screw attachment system you come up with and if you baffle it for sloshing and how it will be protected. Maybe an external tank completely separate from the OE tank as a sump?, but that would make it considerably more complicated and maybe not practical. Should be interesting.

Bob
I ran an external sump system on an old alcohol car. It's been many years and brain cells ago, but I do remember it was problematic and necessary. It was a small tank with a Holley carb bowl attached to each end. Fuel was pumped in to the tank with a high flow low pressure pump. The Holley bowls had their floats still attached and kept the level right. It had vents with slosh tubes installed so that air could get in but fuel could not get out, sort of. We then pumped out of that tank to the injectors. That is the total of my memory of that project. I'm not even sure why we ran it. I do remember it was a pain, and I wouldn't recommend it for a street driven vehicle.

I believe I'm going to mount my sump inside the tank with nothing hanging out the bottom. I'm still working out the details. I'll keep you posted. I'm also taking the 5th wheel out this weekend, give the fuel system a real going over, before I head out on my 1700 miles to CT.
Adam

 

[rweis]

Adam -



A sump inside the tank sounds logical. Something to keep fuel in a central area around the pickup. Maybe something as simple as 2 barriers across the tank on either side of the fuel pickup spaced maybe 6" from the pickup with 1 way flapper valves. A sump big enough to be useful.



As an immediate alternative for this summer's drive through the mountains I think I am going to get a 32 gallon aux tank from Summit RCI-1321C ($150) and just keep the OEM tank 1/2 full. This would give 1/2 of OEM (12 gal) + 32 of aux for 44 gal usable @ 10 mpg (440 miles) which is about all I want to drive a day anyway. I chose this tank because it is below the side rails of the bed and fits the space fairly well. Numerous ways to get it into the OEM tank. Not an elegant solution, but works for me.



The drive to CT sounds really nice. We are going to AR this year for a couple fo weeks.



Bob Weis

 

[rweis]

Gary -



A PWM on a really good pump and fine tuning the supply makes all the sense in the world for exactely the reason you stated. This is an approach that should work well as you stated for the pump. You could even put the rheostat in the cab in case you needed a little more or less pump duty cycle. Flat lands, the psi of your choice, mountains, the psi of your choice, empty, the psi of your choice, loaded, the psi of your choice. Electric adjustability is an advantage you have over the mechanical pump I have. I get X overkill and then have to manage it. But ... ..... all the discussions of mechanical vs electric pumps.



The Walbro seems to be holding up fairly well and seems to be a good replacement to the OEM lp. THe PWM makes it even better.



The concept generally used is also as you stated - massive fuel feed overkill to insure you get at least what you think the VP44 needs. That is why the 150 gph type pumps on a system that will not possibly be able to use but 1/3 of that.



Fine tuning is what it is all about. Supply what you need plus a little safety factor.



The Kinsler bypass valves are AN-6 sized (properly sized to the task, one of their attractions) and highly adjustable (the other of their attractions).



A different observation I am finding is as the summer heat (here getting into the high 80's) gets settled in, the fuel is thinning out and the bypass psi is reducing by about 1 #. Tank feed temps are holding steady at OAT + ~ 15* in my system (coolers etc). Today OAT 88* fuel feed temp was 101*. Output fuel temp was 116* going back to the tank (OAT + ~ 30*). Towing raises both input and output another 5* as you suggested. The PWM would be adjustable to compensate for the thinner fuel in the summer and the thicker fuel in the winter especially in environments like where you live where the OAT swing is considerably more than where I live.



Bob Weis

 

[csutton7]

Bob--i've also noticed over the last few years that when I get in temps above 80* that pressure is reduced--I've seen a 5-6psi drop when encountering outside temps of 100*---I have 19psi at the vp44 and my original vp lasted until last year, which was good for 5yrs at that pressure--just a little more info to shove into the memory bank---



Adam & Bob---

although I do like the idea of the inside sump I think the DI sump and then modifying the return to dump into the sump will be much easier solution to making sure fuel is on hand--even though it will hang down I think it is going to be stout since it has all those bolts to keep it in place in case it encounters alien bombardment, but I still am interested in seeing how Adam completes his system and maybe it won't be as hard as I'm thinking----chris

 

[rweis]

FWIT



Summit has an attachable sump to attach to fuel tanks. Sort of wedge shaped, with the fuel pickup at the back of the wedge. Have zero idea if it would fit our tanks. Zero idea of what the dimensions are.



Bob Weis



An idea that has been batted around before.



1. In bed tank of a size of your choice that will act as the sump (1 gallon to 100 gallons)



2. In bed tank gets returns from

a. the VP44 (what the VP44 returns from the outflow valve and the injectors lubrication return )

b. the RASP (what the VP44 intermediate pump does not use) or whatever you use to pressure feed (13. 5 psi) the VP fuel inlet

c. a constant low flow feed from the OEM tank (to cover what ever the injectors DO use + a little bit)



3. In bed sump tank has a spill over gravity overflow back down into the OEM tank to handle the "a little bit" from 2c



Use the OEM tank as the AUX tank. Since the bed is above whatever lp you have there is gravity feed at all times. When you fill up you fill the OEM (aux) tank and the bed (primary) tank



OR just put a 55 gallon drum on the CC roof

 

[csutton7]

I got my DI sump the other day--nicely machined pc I will say-- I like it, but I do think it can be improved upon possibly by extending it up into the tank more, but when ever I get it installed I'll see if the improvements are necessary and then make the decision if it's needed---don't hold your breath though as I don't get to things to quick anymore----chris

 

[csutton7]

also should add with all the bolts that are used to keep this thing in place I think this thing could withstand a heavy hit and be fine--chris

 

[csutton7]

rweis--I can't count how many times I've looked at that wedge online---but I refrained from buying it as I always thought it wouldn't work---chris

 

[rweis]

Well I am taking a different approach to the sump problem.



I am going to use the OEM tank as the sump.



What I am going to do is add a 55 gallon aux tank (18" x 12" x 60") to the bed.



By using fuel from the aux and not going as far down the OEM tank before refuel the OEM tank becomes its own sump because instead of having 3" of fuel remaining at refuel time (1/8 on the fuel gauge "fuel low" MIL) you just use say 5" of fuel remaining (1/4 fuel gauge), or 7" (1/2 fuel gauge), or 14" (full fuel gauge) depending on the terrain you are in, or what ever is comfortable for you.



The aux tank becomes your main tank. The main tank becomes your sump.



Just stop and fill up when ever the OEM tank starts to drop below full tank and I guarantee you the Draw Straw will have fuel to draw I do not care what terrain you are in.



YOU become the decision of the "terrain vs OEM tank level" that drives when you fill up the aux tank and the OEM tank. Flat terrain you might go to 1/4 full on the OEM gauge, heavily sloped terrain you might go to 1/2 full on the OEM gauge.



Of course you could do this wihtout a aux tank. Just refuel before the MIL light at whatever level is comfortable to you.



Bob Weis

 

[csutton7]

a winning system no doubt---chris

 

[rweis]

Well, I spent the entire day adjusting the springs and shims on the VP44 Kinsler brass bypass I have to regulate the pressure the VP44 sees. I ran about 15 different spring / shim sets with the Kinsler brass bypass.



Sometimes frustrating, sometimes confusing, always a challange.



In the end I got to 11 psi idle (850), 12 psi 1000 rpm (1. 5 psi low) then a slow psi rise to 14 psi at 2200 rpm (. 5 psi high), and finally 14. 5 at 2600 rpm (1 psi high). Most of my driving pattern is in the 1200 - 2000 rpm range and will generally be in the +- 1 psi range.



That is as close as I could get it. Brady at II had a reply to VP44 psi and said the target was 13. 5 as the rpm increased to minimize internal pump stress. I took the approach that if I was going to be off much it was going to be at lower rpm's and more accurate at higher rpm's.



I will run this configuration and report back it I see anything that needs changing. I know OAT > ~ 90 will cause a 1 psi loss, but I will have to see what happens with the spring / shim configuration I have and see if that still holds true.



Bob Weis

 

[Gary - K7GLD]

Got my own homebrew regulator installed right at the VP-44, where I also take my fuel PSI readings:



#ad




After 3 tries on spring length, hit PSI dead-on at 15 PSI - steady as a rock, until heavy load draws it below the set point - I'm figuring to try replacing my 7 PSI Carter pusher with my spare OEM LP - the extra 10 PSI or so I would gain MIGHT fill in the PSI "hole" of heavy demand under load, and completely stabilize PSI under ALL circumstances - plus, the swap of pumps can be done in just a few minutes because they are externally identical...

 

[csutton7]

concerning the vp and pressure--I finally had to replace my original vp after 7 yrs of which the last 5 was at 19psi for most of it's life--just a little more info that is factual information to file away in the memory banks----I will also add that a lot of time I drove with the EDGE Drag Comp box off and would only turn it on to destroy some punk or for a sledpull or dyno----chris

 

[Gary - K7GLD]

concerning the vp and pressure--I finally had to replace my original vp after 7 yrs of which the last 5 was at 19psi for most of it's life--just a little more info that is factual information to file away in the memory banks----I will also add that a lot of time I drove with the EDGE Drag Comp box off and would only turn it on to destroy some punk or for a sledpull or dyno----chris

How many miles on that pump Chris?



This latest VP-44 I now have on my truck will be getting the best available care - fuel additives for lubricity, extra cooling for the pump electronics, and stable fuel PSI in the recommended range under all operating conditions. It also has all the latest Bosch revisions and upgrades - so we'll see if it lasts any longer than the 40K+ the OEM one did...

 

[csutton7]

wish I could tell you exactly--when I went from the 3. 54 to the 4. 10 my speedo has been off and then with the 35'' of 36'' tires it's way off, but if I was to garner a guess I'd think somewhere around 90k--I don't rack up a tremendous amount of miles, but a lot of short trips to lumber yards and the like---chris

 

[airacer25]

As a nugget in this arena, I must say, this is a good thread...



Thanks for all the reading and info!!!

 

[EagleEye]

Revisiting and questions...

Back about 3-4 years ago, I placed a Carter pusher back by the tank and have had good luck ever since.



I recently started seeing intermittent/low psi on my SPA and figured it was time to check the pumps. Checked both out and all seems good, but slight debris in my Carter pusher... OK... figure I gotta drop the tank, and while it is down going to remove the strainer and place a Racor 645-r10 back before the pusher.



I called Racor Tech and inquired about the different applications. The tech threw out a formula (which Racor uses) and said a 45gpm would NOT be sufficient, and a 60gph filter would be undersized as well. HPx0. 18=gph



OK, so I call Cummins/Fleetguard and inquire as to the flow rate of the stock fuel filter. 59. 97gph.



Here's the questions...

Anyone ever come across Racor's formula before?

Stock supply lines are 5/16. I wonder what they can flow?

I have seen people install the Racor 645-r10 (45gph) and others. Undersized?

What is the internal bypass/relief psi of the stock lift pump?



I ordered a 660-r10 with 60 and 45 filters so I can mix and match. Figured I might try JUST the stock lift pump back where the pusher is, install the Racor prior to the lift pump, remove the tank screens, and utilize the stock filter for insurance.



Any input on any of the above?

 

[rbattelle]

HPx0. 18=gph

Sounds like a very rough rule of thumb, which should never be used to actually design anything. It's just something people throw out at parties when someone asks a question and they don't have time to sit down and calculate the answer.



I'd ignore it. Do your own calculations, and decide from there.



Ryan

 

[csutton7]

well I'm not fan of the pusher pump setup in the first place, but you've had good luck and that's great---again electric fuel pumps are great pushers and not very good suckers, so you're going to strain the pump IMO even more than the OEM strainer, but hey it may work out fine also--definite good test--I agree on ignore and work off your own calculations---chris

 

[rweis]

I use a RACOR 690 r10 right out of the tank.



My thinking on how I arrived at 690.



I think the max flow at the VP44 is 45 gph. I did not want the filter to be right at the limit because the filter is going to degrade as it filters. The 60 was the next choice. However, the sucking vs the pushing thing came up. I can see how sucking is harder than pushing. I went up another notch to have a bigger filter area and make the sucking easier. Next notch was the 690. I also did not want to go any larger than the 10um and that small of a um also implied to go up from the 660 to the 690.



Then I took the weather temperature into account. When cold the fuel is thicker and not flow as well the filter was going to be a even greater restirction so the 690 had a second vote. If I were in colder climate than FL then I would have put a fuel heater in the 690 and probably an additional in line fuel heater just to be absolutely sure the fuel can flow in the winter.



They sell filters and probably want to make absolutely sure they do not undersize an application. I would imagine the . 18 has some fudge factor in it. If it is even close to approximately accurate the 690 will support 500 hp which is well above of where I am, again somewhat over built, but better over filtered than under filtered (690).



I also overbuild just about everything and I liked the extra ports in the head of the 690 and I measured the verticle length of the bed pocket where I was going to mount it and the 690 would fit in the bed pocket easily.



I have 80k on my 690 r10 and have had not a lick of any indicated problem. I did get a bad load of fuel about 3 years ago and last week. The recirculation of the fuel cleaned up the fuel in about 1 1/2 hour. Symptoms were rough at idle speed, ok at anything above idle. Threw 0602 code as well. After about an hour and a half no rough idle, no code 0602.



RACOR does filters worldwide and I tend to trust them just because of how long they have been doing it and how diverse their product line is. I also run their RACOR 802LFS bypass filter.



My thoughts and why I did what I did.



Bob Weis