Can someone explain to me the whole fuel issue with the 7.3 in newbie terminology. what is the fix.
Just looking for better running and fuel economy, not a race truck

 

Are you speaking of the dead head fuel issue and the reason for the different injector in #8?

 

Starting at the in tank mod, frx, regulated return, banjo bolts from ITP, injector 8, All these different fixes. I have read a ton about all these things and am confused. I was hopeing some one could start at the begininig and run me through the problems and all the fixes. I know this is daunting and the fixes are different depending on what you can afford.

 

The intank mods do a few things. The hutch and harpoon make filling up much easier by shortening the filler neck and vent pipes. The next intank mod is removing the mixing chamber that has a couple screens in it that get clogged with debris over the years and many gallons of diesel run through them. The mixing chamber gets the fuel from the pickup and the return fuel from the filter bowl. When the return fuel is pushed back to the tank it get air mixed in. When this fuel gets mixed with the pickup fuel it will have air bubbles, which are bad all the way around.

The engine fuel mods like RR or FRX eliminate the deadhead issue where the fuel is pumped into the head from a single point with no return citcuit. Having no return leads to air bubbles getting in the heads and the only way out is through the injectors. Since air will compress and fuel will not, the pressure will vary and cause issues (cackle).

When you get down to the banjo bolts you are just providing more flow, which may help, but not nearly as much as prepump or return mods.

 

Thank you. What all is needed to do the " intank mods"? Do you add a external filter to take place of pick up screens. Is the frx just a cheaper way to do the fuel mod? do they both accomplish the same thing? What is the difference? Thank you for your patience.

 

The in-tank mods do a few things. The Hutch and Harpoon require no parts, just cutting the filler and vent pipes. The delete of the mixing valve does require parts including an external filter as you no longer have the screens to collect the return debris. One option to get is the Sinister Diesel Pre-Pump kit. For $159 you will have everything needed to do the tank work. Clay at RiffRaff Diesel also has an In-Tank kit coming out, but I don't think it is on his website yet.

The FRx is more affordable than a full RR system and it is not adjustable. Most buy the RR system and only set it once so the adjust-ability is not needed for everyone. Eliminating the "dead head" issue is the main purpose, and they both do that.

If you are curious about the crud in the mixing chamber screens, here is a picture from a well maintained truck with 119K on it. Both screens look the same, and they are not serviceable without dropping the tank.