2006 ford f250 SD converted to 1997 12 valve with fuel delivery problems

[Kerry Bradley]

This is the second ford that I have converted over to a 12 valve cummins . Both were 6.0 powerstroke trucks . The first is a 2003 f250 SD to a 1998 12 valve cummins and all is well . But this 2006 f250 SD , when fuel tank is full to down to 3/8 tank the truck starts and runs fine but when fuel gets down to 3/8 tank and sitting over night seems to have a problem with fuel flowing back towards the tank and will just about run out of battery power before starting and after starting , runs questionable at times . I am running the truck on the block mechanical fuel pump and replaced with a new one recently . I since have dropped the tank and found a leak in pickup tube so to fix that problem , I installed a sump in the bottom of the tank . Problem solved , right ? Wrong ! I am at 1/4 tank and truck runs great all of the time but when the truck sits idle for 4 hours or more fuel is again running back . Crank and crank to get fuel back to the injectors and when engine starts it runs great no rough idle no hickups on road or at stops . Just runs great .
The Dodge Ram that I took this engine out of did not have this problem and it might sit a week or two between starts . What am I missing here ? Any help would be appreciated .

 

[Wayne M.]

I would hook up a temporary, isolated 5 gal supply just to eliminate the engine from chassis. Make that tank at the same height or lower than the stock tank.

 

[Kerry Bradley]

Wayne , I will do that and let you know in a couple of days. Should be easy enough .

 

[Morlock]

Wadip Kerry, I have the same name haha, and so I have a 12 valve cummins with p pump from a 96 freightliner mt45 FedEx truck, and was thinking about putting it into my 2006 silverado..It's just an awesome engine and the box truck frame sux, you've done something similar, any thoughts?

 

[Kerry Bradley]

Diesel conversion specialists will have the kit for that . The Silverado is a 2500 , right ? Is it 4x4 , just wondering? It will be a little tighter fit than in a Ford but yes go for it . The only problem with converting a gas burner to diesel is with emissions testing if you have them where you are . These are the last trucks i will ever have . The engines will last other than the norms on them and just have to replace other norms on the trucks themselves . Take your time and have fun . Take many pics as you go and post . Diesel conversion specialists will help with info you will need at times but they are sometimes slow to get with you on things and you will have figured it out before they do . Again take your time and have fun . Holler at me if you need more info . No expert but been through a couple of these swaps with Fords .

 

[moparguy]

Not elegant at all but; solenoid activated anti-drainback valve or appropriately sized check valve?

Good Luck,

RonR

 

[AEdelheit]

Have you made sure the fuel tank vents are clear and it is not creating a vacuum in the tank? Very rare but possible.