What the heck is this? Extra fuel return?

[6 Nebraska IDIs]

Ok, I dont have pictures. But I can describe it well enough you guys should be able to tell me WTH its doing.
Ok, its a aftermarket hose that is tapped into the fuel filter head elbow and runs straight down to the injector return lines. Is this supposed to be there? It looks really out of place to me.

 

[fellro86]

It is actually factory, but is just trouble. I have been told it is deleted per Navistar instructions. I have had it on al the 6.9's I have dealt with so far, deleted on the runners...

 

[6 Nebraska IDIs]

So you're saying to take it out? I guess none of ours have them, this is my low mile truck, and there's ALLOT of stuff on this truck that the bolts have never been turned before.
What was it intended to do?

 

[fellro86]

It is a bypass for overpumping from the filter to be returned to the tank. There is a check valve in that brass fitting where the hose hooks up to that likes to stick, and then drain the filter back to the tank when sitting. It sucks to go start the truck, to have it essentially run out of fuel 30 seconds later. I capped the nipple on the brass fitting, and then the return line on the front injector. No problems, been like that for over 2 years. No problem with the fuel drain back any more either...

 

[bng]

yeah its also a source of air entry from dribling return line pia o rings . I simply changed it to a 1/4mp x 3/8 ff 90o elbo also silver brazed sight glasses in oulet of ff line & i/p return. no more bubbles or surprises [a couple of return lines still weep but no more hard starts. hope it helps butch

 

[Andylad13]

my problem with hard starts when i first got the truck was that brass fitting on the filter head. i replaced it through ford, and new return lines and o rings, and i've never had air leaks, or fuel return problems after that.

if you've been having a problem with it then you can cap it, but if its fine and working properly i would leave it alone.

 

[6 Nebraska IDIs]

I've had problems with it bleeding off since I've had it, and even has a tone change problem like it leans out periodically while driving.

 

[Andylad13]

that doesnt sound like a problem from the return from the filter. i could be wrong though. i would check your filter itself for a problem like that, however, either way, if your having problems...**** can it!!

by the way, what do you mean by bleeding off? like the damn line comes off when driving??

 

[6 Nebraska IDIs]

air bleeds into the system, somewhere. Its getting worse too! all my injectors and lines are original, never touched. just that one from the filter housing. But there are literally no oil or visible fuel leaks ANYWHERE on this truck. Its dry everywhere. I dont know where it's getting the air. But everytime I start it I have to crank atleast two 45 second crank times on the starter before it will fire.

 

[Andylad13]

thats definatly air! sometimes fuel wont come out of a hole that air will go in. injectors and lines should be ok.

check the return lines themselves. dont look for fuel though, look for cracks. my original ones were a braided material and when i took them off the caps, they broke in half!! all of them!! and they looked good by just looking.

so check those good! that should be where any air is comming in. also check the drain on the filter. tighten that bad boy right up if you can. good luck.

oh yeah, you prob already know this but i hope that your not consistantly firing the starter for 45 sec in a row.

 

[Mr_Roboto]

AFAIK air will not cause a no-start, since the truck can start on what fuel is already in the IP. Normally air will cause the truck to run for a few seconds, then the motor will die when the IP starts sucking air.

 

[6 Nebraska IDIs]

No no, I let it cool for about a minute before I try it again.

Roboto, what is AFAIK? Well the returns are cracked, atleast the original grey paint is cracked.
Everyone's told me that even though it has under 90,000 original miles on it, I need to replace the IP and injectors because they can be dried and bad after sitting for so long.

 

[Mr_Roboto]

As Far As I Know = AFAIK

 

[FordGuy100]

Mine has it, and my truck starts fine. I suppose I should take it out though, if a lot of people are having problems.

 

[Rot Box]

I've had problems with it bleeding off since I've had it, and even has a tone change problem like it leans out periodically while driving.

I'm having the same exact problem! Kinda getting annoying when its -5 outside..... Hopefully we can get things figured out

Btw I'm new here and greetings from Northern Utah