I want to add some gauges to the truck. I really want it to turn out clean. I think eventually, I'll have the pyrometer mounted on the A pillar and fuel pressure in the dash under the stereo (I saw a pic of a nice installation on here).

I just took some pics to make sure I understand how it is plumbed. Please correct me if I'm wrong.

This is where the fuel enters the filter from the lift pump.

 

This is where the fuel leaves the filter on its way to the hi pressure pump. Viewing from below.



Clean fuel from the filter to the hi pressure pump. Viewing from above.

 

In the pic below:

A - inlet to the hi pressure pump from the clean side of the filter
B - not sure, leakage back to filter for recirc?
C - hi pressure line to fuel rail



This is where fitting B leads to, what is it?

 

It looks like I can purchase the following banjo bolt with 1/8 NPT and exchange it with fitting A to wire the fuel pressure gauge to. Am I correct? This looks like the cleanest way to do it.

 

imho ditch the banjos, get jic fittings easy to install, remove, reinstall. less restrictive to flow.

 

How would that work in this application? I know what a JIC fitting is, but how would it replace the existing banjo fitting?

 

Dot, most of your thoughts are correct, except where the fuel enters the filter, that is to the left of the red circle that you had. The banjo bolt you circled and the one to the left of the filter on the front, are all the return fuel lines (return from pump, head, rail relief) ect.

 

Thanks TAS

 

OK, got a better pic, X is where the fuel enters the filter from the tank, I traced that one back to the tank. Y is a return as you said.

 

Now, what's the deal with these two lines going to the back of the block?
I can't see what they're connected to.
#1 is the hi pressure line in both pics.
#2 points to the same line, it's one of the returns.

From below.



From above.

 

More evidence that someone has been messing around.
Definitely not a factory piece. The filler line is kinked a little bit.
Apparently, there's a checkvalve in this nipple because I don't see any fuel coming out of it.