Best Return Line Setup for Peterson CNC Caps? (1/4" vs 3/16" Hose)

[idiBen]

I'm looking for some advice on the way I currently have my injector return lines set up.

I purchased some Peterson CNC aluminum return caps that I purchased from Classic Diesel Designs. First impression is that the quality is very good. My question comes from the size of the fuel barbs, which use 1/4" return hose connections. My truck originally had the factory-style setup with 3/16" return hose, so I had to use reducers to connect everything to the factory brass return manifold (see attached picture).

My first attempt used aluminum 1/4" to 3/16" reducers from Summit Racing, but I could never get them to seal completely and they would seep fuel. I replaced them with plastic reducers from O'Reilly's, and so far they have not leaked.

My concern is long-term reliability. I'm wondering what the best solution is:

1. Leave the plastic reducers in place and run them until they become a problem
2. Replace the brass return manifold/barb fittings with 1/4" barbs so the entire return system is 1/4" and remove the reducers altogether
3. Stretch 3/16" fuel hose over the Peterson CNC return cap barbs

Has anyone else run Peterson CNC caps with the factory return manifold? If so, how did you handle the hose size difference, and what has held up the best over time?

 

[rreegg]

Sorry don’t have any advice but all I can say is “oof” and will be watching this thread. These fuel return lines will always have the last laugh

 

[8769bigred]

I was looking into getting these aluminum caps as well.... Going to be watching your project!

Thanks for finding out the hard way for us lol

 

[idiBen]

I'm considering the option to make my own 4 way to keep entire return line setup as 1/4. Thinking of this setup:

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I need to see what size fitting runs from the injection pump to this 4 way though.

 

[IDIBRONCO]

My truck originally had the factory-style setup with 3/8" return hose,

Not from the factory it didn't. The only two sizes from the factory were 1/4" and 3/16". That hard return line was the early style and it used the 3/16" return lines. The return line to the tank behind that junction was 5/16" from the factory. If anything was 3/8", it was changed out after it was bought new.

 

[idiBen]

Ah, you're spot on IDIBronco! Both of my post above should say 3/16. Thank you! Going to edit it to avoid confusion.

 

[IDIBRONCO]

Going to edit it to avoid confusion.

I have to admit that I was a little bit confused too.

 

[IDIBRONCO]

Now that I think about it, you might be able to come up with some 1/4" fittings that are similar to what the later style of return lines use and change it all over to 1/4" hose. Here's my return lines from when I redid them last fall. Yes I did run the crossover underneath the intake manifold to avoid the heat from a future turbo.