LB7 fuel junction block banjo bolt

[2500HeavyDuty]

its plugged so that when the fprv pops open at around 23k psi the fuel has no place to go since it would have to flow though the banjo bolt that has been plugged. be sure when plugging it that the holes at the base of the banjo bolt are still open so that the fuel from the injector return line can still flow though

I have a write up on diesel bombers. along with many others. lemme dig it up real quick.

http://www.dieselbombers.com/lb7-bombs-aftermarket/21777-dmax-tech-plugging-fprv.html

 

[2500HeavyDuty]

The banjo bolt is hollow with holes in the side to allow the injector and cp3 return fuel to pass through the sides and the FPR valve to bypass through the center. Most of the Dodge guys block theirs by tapping the end 1/8" NPT and using a allen plug that recesses just slightly below the end of the banjo bolt. On my Dodge I slid a small round piece of steel in the end of the banjo bolt and Tig'ed it closed. Just make sure you don't block the side holes and the injector/cp3 return.

i got the idea from a dodge guy who is a certified mechanic in damn near everything diesel, he told me it would me safe if i used a steel plug and he goes it all the time when he installs modded cp3's on dodges and dmaxes.

i dotn have a welder so i really couldn't weld the end of my banjo bolt shut. tapping my only option then

 

[duramax-rob]

I don't know if I'm hijacking this thread, if I am I would appreciate someone putting it in the correct area. My 01 lb7 just had the fuel pump and reg replaced at the dealer and the banjo bolt at the back of the drivers side head banjo bolt bottomed out and shut off the return for that side. He used all the correct new gasket, u shaped, and it shut off the return fuel and blew the top of one of the injectors off. Is this the banjo bolt you are all talking about and has this happened to anyone else and know why it bottomed out?

Any help would be appreciated. Thanks duramax-rob

 

[Idaho CTD]

That isn't the same banjo bolt. It sounds like you have a restriction somewhere else. Either something fell in the hole or the hard line has blockage. I would pull the return hard line and blow it out and blow out the return line under the valve cover as well as the hole in the head. The 4 injectors/side share a common return line that has a banjo bolt into the head. Outside the head there is another banjo bolt that goes to another common return line from the injectors on the other side of the motor, cp3 relief, and rail pressure relief valve (the one we were talking about above).

 

[2500HeavyDuty]

the bolt we talkin about is the one that threads into the fprv on the fuel junction block

 

[duramax-rob]

Idaho CDT, I appreciate your reply. We did what you stated above and it still happened again. Finally installed anothe washer under banjo bolt shoulder and that finally fixed the problem. Also I think he overtightened it too tight. said most of the ones he removes are just barely past finger tight. Just a heads up to others now.

duramax-rob

 

[Idaho CTD]

The banjo bolts are hollow so you can't tighten them too much or you'll risk breaking them, especially the smaller ones going into the head.

 

[duramax-rob]

We checked the banjo bolt lengths and they all seem to be the same lenght and even had parts look them up and seem to only call for one length. Did we screw up some where and maybe put a longbolt in where there sould have been a short bolt and are there different lenghts that you have observed?

Greatly Appreciative duramax-rob

 

[Idaho CTD]

I haven't noticed if the inside banjo bolts are longer then the outside but it's possible.

 

[duramax-rob]

Thanks for the help. Absolutely appreciated!!!!!!!!!!!!!!!!!!!!!

 

[bullfrogjohnson]

Bump.....What size allen head set screw do we need to do this?

 

[sweetdiesel]

This was my first setup that ended up leaking at 160mpa
but i thought you guys would like some pics

 

[2500HeavyDuty]

Bump.....What size allen head set screw do we need to do this?

1/2

 

[02dirty]

thanks for the info guys i just did it and i am impressed

 

[03 D-max]

so whats a safe psi for the lb7 injectors?

 

[sweetdiesel]

so whats a safe psi for the lb7 injectors?

160mpa is safe But who on this site plays safe?

 

[03 D-max]

160mpa is safe But who on this site plays safe?

so if 160 is safe what will 180 do:devil:

 

[sweetdiesel]

so if 160 is safe what will 180 do:devil:

I run 180mpa I havnt had any reprocutions from it YET

 

[03 D-max]

I run 180mpa I havnt had any reprocutions from it YET

well i guess i will be testing mine at 180mpa, time will tell.