Fuel System Mods

[IdahoF350]

So I'm pondering some low buck mods with things I now have laying around. Thing is, I recently acquired a later 2005 6.0 38 gal. fuel tank. My truck is a long bed, so the 38 gal. tank is a direct swap, and I got the plastic heat shield, the tank straps, and the skid plate from the donor truck.

I can do the harpoon mod to the tank, easy. The fuel level sender is the same range and connector even, and there is no mixer in the 6.0 fuel sender assembly. You don't exactly here about problems with air in the fuel lines on 6.0s, it was never a problem with mine anyway. If I use the later sender, I avoid the need for any internal tank mods that the hutch mod deals with.

So can I just replace the o-rings in the fuel line connectors and avoid the rubber hose? I know the Hutch mod deals with adding an in-line pre-pump filter, and I can figure something out there, but I'm not big on having endless feet of rubber hose in place of hard line, especially when I have access to the OE adapters to utilize the stock lines or minimal lengths of rubber hose.

Thoughts?

 

[emev0l]

Your going to want larger lines. I believe stock fuel lines from the tank to the pump are 5/16. Depending on what fuel pump you plan on using your going to want a 3/8 to 5/8 pickup and lines.

 

[rusty1161]

So I'm pondering some low buck mods with things I now have laying around. Thing is, I recently acquired a later 2005 6.0 38 gal. fuel tank. My truck is a long bed, so the 38 gal. tank is a direct swap, and I got the plastic heat shield, the tank straps, and the skid plate from the donor truck.

I can do the harpoon mod to the tank, easy. The fuel level sender is the same range and connector even, and there is no mixer in the 6.0 fuel sender assembly. You don't exactly here about problems with air in the fuel lines on 6.0s, it was never a problem with mine anyway. If I use the later sender, I avoid the need for any internal tank mods that the hutch mod deals with.

So can I just replace the o-rings in the fuel line connectors and avoid the rubber hose? I know the Hutch mod deals with adding an in-line pre-pump filter, and I can figure something out there, but I'm not big on having endless feet of rubber hose in place of hard line, especially when I have access to the OE adapters to utilize the stock lines or minimal lengths of rubber hose.

Thoughts?

Don't you already have a 38 gallon tank in your '99 CCLB?

Rusty

 

[IdahoF350]

Ok, so the Harpoon mod is done to the spare tank. That's not as easy as it's made out to be if you are a bigger guy with big hands and long arms, getting the cutter on the tubes in a position to be able to squeeze them is a bitch. I underestimated that one a bit.

The '05 sender assembly appears functionally identical to one that has had the Hutch mod, just a closer return point with a rubber nipple check valve on it, so I'm going to run it unless it happens that the line sizes are different.

Been thinking about the screens in the mixer and if they were worth anything from a filtering standpoint, they'd plug up all the time, and guys would be bitching about them regularly. It's more likely they are there to break up any air bubbles from the return line.

So the pre-pump filter, while fine in principle, is going to be WAY more than anything in that mixer is capable of. It only concerns me that putting a pre-filter in front of the pump may put an unnecessary load on the pump, cause cavitation, and increase the load on the pump, reducing the output and shortening it's life.

I'm looking forward to doing this as my Friday project. I'll let everyone know if I run into any snags or if it goes smoothly.


Sent by my right thumb!

 

[V-Ref]

It only concerns me that putting a pre-filter in front of the pump may put an unnecessary load on the pump, cause cavitation, and increase the load on the pump, reducing the output and shortening it's life.

That helped me decide to run a sump. It's helped the stock pump in my two pump fuel system hold pressure too. Only in the biggest tunes on a longer extended run do you see a small pressure drop with the factory SD pump. I've come to conclude the positive head pressure from the sump is why.....dunno?

 

[mandkole]

Idaho, I'd long thought about the same thing in regards to these mods on stock fuel systems. Their main value appears to eliminate/repair any broken parts in the stock sender assembly and that would draw air when the tank level drops below the broken area. Pump reliability in stock systems demonstrates that there is not a huge prepump filtering issue. Honestly I would not put a prepump filter in a system with stock supply line as there is not enough volume to move across the filter and it would seem to strain the pump more as it gets dirty. A 10-20 micron prepump filter is more suited for bottom tank sump supply and larger lines.

I agree that sumps would seem to add head pressure benefit to supporting a stock pump but at the risk of more water/trash in the system (that needs a filter/separator).

If you have needs met by the stock fuel system , then what you are doing is just fine.

 

[IdahoF350]

When I build a fuel system for a road racing car I run a central sump, and sometimes foam in the cell. For drag racing the sump is at the rear of the tank, and foam is not beneficial.

I've seen the various sumps like the Hellmans, they are fine I guess, but I designed my own if I was ever going to go down that road back when I had my 6.0L. It's a little different than anything else in the market, actually traps fuel at the pickup, and would allow you to drain the tank of all but a couple quarts of fuel.

But ultimately, yes, pulling the fuel up and out of the tank creates a vacuum on the inlet of the pump by itself. "In-Tank" fuel pickup inserts were all the rage for Mustangs from the mid '90s on, and I saw a higher than normal failure rate with everything from Holley "Blue" pumps to A1000s, especially when used with a pre-filter when using those inserts in a stock tank, and that is exactly how the stock Super Duty pickup is configured, so I don't want to replicate a known poor system configuration.

Thanks for the input guys.


Sent by my right thumb!

 

[IdahoF350]

So it's all done. It's now an Early '99 with the Harpoon and Hutch mods.

2005 tank is physically the same as E99.

2005 heat shield is a little different, covers more area up top.

2005 fuel filler neck will accept a high speed fuel nozzle at a truck stop, the E99 would not.

2005 fuel cap is different than the E99 cap, it is a threaded style cap, as opposed to the E99's push in and twist to lock design.

2005 fuel level sender is the same ohm range as the E99, the electrical connector and the wiring color codes are the same, although the pigtail is a few inches shorter, but not an issue. The fuel line connection is identical as well.

2005 Skid plate bolts up using existing holes.

I know that some of you have had your 7.3s for so long that some of this is ancient history and or seemingly trivial. Having come from a 2005 6.0L back to this E99 7.3, there are a lot of subtle differences that I miss from the '05 like the fuel filler. Now I can fill at a truck stop and not have an issue with the larger nozzles.

As far as any difference in running, I'm going to say the injection system seems a tad but less noisy at idle, but a subtle difference at best. I haven't really driven it yet to notice any running differences, and I don't expect much of anything.


Sent by my right thumb!

 

[Arisley]

I can fill my early '99 up at a truck stop. You can rattle the big nozzle around in it. One of the first mods I did to my truck, five minutes with a sawsall and a dremel.

 

[Ron's Power Stroke]

:whs:
only i used an air chisel ...we did the same thing back when we had a choice of regular or unleaded gas...

 

[IdahoF350]

Well, for what it cost me for the updated parts, I was happy to just swap them and be lazy about getting creative modding the stock part. And the stock fill and vent hoses were not in great shape, so they are now replaced with updated pieces as well.

Put almost 200 miles on it today. The sender doesn't make the gauge read like it has a mind of it's own, it's not so erratic. But as far as any improvement from removing the mixer, I'd say absolutely none, in sound or performance. Truck runs the same.

When I fill it next time I'll see where I land before it's full to the top of the filler neck, if that's the only real gain from all this, I'm still happy, I've got maybe $20 in all the parts after you subtract the value of the fuel that was in the tank.

If anybody in SoCal needs a stock 38g tank, sender assembly, heat shield, or spare filler neck and cap, they're free to a good home if you pick them up or meet in the AV or Bako, or for the cost of the ride if they need to go farther on the smaller stuff, the big stuff isn't worth shipping.


Sent by my right thumb!

 

[IdahoF350]

So there has been one notable improvement from the above mods. The fuel gauge is now more consistent, as in it doesn't lose it's mind as you go up and down hills changing by 1/8th of a tank or slightly more, it now changes only very slightly, and more gradually.

Aside from that, filling it has been faster with the Harpoon Mod, so all in all, very happy with "cheap" upgrades and legacy mods.


Sent by my right thumb!

 

[RichardinVirgina]

Hello, I wonder if you will take the time to reply to me? Here is my question. If I do the Hutch and Harpoon Mods do you think I will cause my fuel pump to fail if I installed a post tank / pre-pump 20 Micron filter as I describe here?

I have an issue with my sending unit which indicates my tank is full which I know it is was not. I was needing fuel the other night, so I put in $30.00 (about 10 gallons) and now the needle seems to stay a tad bit above the full mark.

In addition, the truck seems to have started to act a bit sluggish and I am pretty sure there is a problem inside the fuel tank based on the info I have looked into via reading about this issue on this forum and some YouTube videos.

So I am working up to the task at hand of dropping the tank and checking for the problem, and while in there will probably do "the Hutch and Harpoon" mods.

I also am going to add a post tank/pre-pump fuel filter. I want to hear some feedback from this forum.

The post filter parts I am considering using here are part numbers: Fleetguard 142784S Fuel Filter Head by Cummins Filtration (or mount head Fleetguard #3930618S); plus the mount bracket, Cummins Filtration.com part number: 3312054S; and a filter like the Fleetguard FF105.

OK ... does anyone know what the micron rating is on the two small tube filters that I will be eliminating from the pickup on the sending unit when I do the Hutch Mod?

And finally what do you think? Any suggestions here?

I want it simple and I am not into fancy stuff or overkill, this is a work truck. Thanks!

My rig: 2001 F-250 7.3 Turbo with 190K

 

[Ron's Power Stroke]

this kit will fix all your in tank problem (except for the sender)
https://www.strictlydiesel.com/p-2662-driven-diesel-fuel-tank-pre-pump-kit-hutch-mod.aspx

 

[RichardinVirgina]

One concern I have needs answered OK?

this kit will fix all your in tank problem (except for the sender)
https://www.strictlydiesel.com/p-2662-driven-diesel-fuel-tank-pre-pump-kit-hutch-mod.aspx

Thanks, Yes I have been considering this KIT from StricklyDiesel as an option.

One concern I have come across and need to resolve a good feeling about is this: Will the installation of a post-tank/pre-pump filtration set-up cause the fuel pump to fail premature?

Reading about some of these installs has me concerned about the flow rate through the filter and the vacuum pull by the OE pump.

Any ideas? Comments?

Thanks again:thumbsup:

 

[Ron's Power Stroke]

never heard of any trouble with the pumps do to the filter..many of us have run with a spin on filter post and pre pump for the past 15 years...

 

[RichardinVirgina]

never heard of any trouble with the pumps do to the filter..many of us have run with a spin on filter post and pre pump for the past 15 years...

That sounds good.. Was getting a bit worried I would cause more problems. I was reading some guys posts where he had problems, seems he had a two filter set-up and had them in reverse order or something and starved the pump until it quit altogether?

I want a simple small set-up just to catch debris coming up from the tank (in case the pick-up screen missed something etc.) before it gets to the inlet side of the ford fuel pump and gets sent on to the fuel bowl.

The FF105 filter I plan on using does not have a water drain on it, but I do not think it will be a biggie. I also plan on installing two small ball valves one on each side of the filter mount head to be used when I check or change the FF105.

I am going to assume you have done the Hutch and Harpoon Mod then?

What other mods have you done that you feel really are needed?

Thanks again, Richard

 

[Ron's Power Stroke]

there are alot of simple mods you could do to help your truck run better..getting rid of that screen in the tank is one of them...doing a regulated return is another...

 

[Ron's Power Stroke]

hear is a good read
http://www.guzzle7pt3.com/index.php

 

[RichardinVirgina]

Yup been to Guzzle many times! Thanks Again

Yup been to Guzzle many times! Thanks Again

Should I be concerned that the FF105 20 micron filter has a flow rate of 91.94GPH?? In reading a post from the owner of Stricklydiesel, the Baldwin BF1212 they sell with their Hutch Mod Kit boasts a flow rate of 1psid @ 210gph just wonder if you had an opinion on this?