I think the FASS harness uses the stock LP wires for a trigger, but it still uses a relay. This was how it was done on my previous 2nd gen, I hope the 3rd gen harness will be the same.

 

Yup that's how the FASS harness does it.

 

The nice thing about using the FASS harness ($46) is that it already has the correct plug for connecting to the 3rd gen lift pump trigger wires. If you use a generic harness & relay like from Jeg's ($25-$30), then you have to improvise. You could buy a LP plug and wire tail direct from Cummins (around $16) and solder it to a generic relay harness. Cost-wise it is roughly the same by the time you figure shipping.

 

Looks good...... but I don't see an electrical wire to the pump.

 

man, not only does the job look clean, but all those bright blues really stand out and just give the engine compartment a "cool" look. Really nice work, my hat's off to you.

 

Nice setup!! I would like to install a 2 micron filter soon too. Where did you get the filter mount/housing? Is there a part number?

 

Well as from you read above I did the install a few days ago. Today I installed the FASS electrical harness, a Geno's tapped billet filter cap (no worries of that thing cracking) and a second digital fuel pressure guage. One guage I have prefilter and I am seeing around 20psi. The second is right at the CP3, I am only seeing around 1.8 psi. This shocked the crap out of me! It does not drop below that with the Juice on level 5 and the pedal mashed. So should I be worried about the low pressure? I'm sure I have the flow to it, but super low psi.

I also tried pinching off the 3/8" CP3 by-pass and it only made my pre-filter pressure increase.

Any thoughts fella's?

 

Look at the flow rate graph of the Walbro, at 20psi it is producing nearly 60gph, just cause you have a dramatic pressure drop, the flow is obviouslt there, cause as you said, you don't even see a pressure drop.

 

Wow, 1.8PSI is lower than I would have expected. My 0-60 gauge on the Geno's billet cap is seeing around 22psi, and my CP3 0-30 gauge shows between 10-14PSI at idle with two return lines.

I guess it shows that those AN fittings really do remove the stock restrictions (banjo bolts, steel fuel lines, etc). What if you pinch the return line between the CP3 outlet and the fuel canister? Does the PSI on your CP3 gauge rise?

 

That's what you get for having two filters, or maybe just from the CAT filter alone. If you see higher pressure as you go upstream (towards the fuel pump) then you have restrictions. 28psi before the filter(s) and 1.8 after says your filter is a big restriction. It's not voodoo magic, less fuel is getting to the CP3 side of the filters. A 26psi drop is *huge* imho.

Andy

EDIT: What is the internal regulator on the low pressure side of the CP3 set to?

 

Blast Chamber are you monitering the return pressure from CP3? I have mine (not shown in the pic's above, just added today) mounted right at the CP3 inlet, if you got a reading there do you think you would have somewhat of the same pressure? I'll have to try pinching off the return tomorrow, earlier I just tried pinching the by-pass.

If pinching the return nets me a little pressure, I may have to put the banjo's back on the return. I still have my Geno's tapped banjo that was on there before, plus I have 1/8" NPT to -06 An fittings. I ordered too much, but i'm kind of glad now since I may have to play with configurations a bit.

I just hope I get everything up to par by Saturday as I have to make take a trip down to NC.

 

I don't think the Cat filter is that restrictive. Fuel shot out of there when I was blowing out the lines by hooking the Walbro directly to the battery, so i'm deffinetly getting the fuel there.

Enlighten me on the CP3's internal regulator please.

 

Well I don't think you can adjust the internal regulator on the CP3. Either it's wide open, which means high flow and low pressure, or you've just got too much restriction from the filters. You might want to try hooking up just the stock can to see what it does for comparison.

To get fuel pressure that low at the inlet of the cp3 just doesn't seem right, but I could be all wet!

Andy

 

I don't remember Superduty ever giving any pressure readings at the CP3, but he did go with a 5/16" CP3 by-pass. I with others I have seen went with a 3/8", SD said (whether right or wrong) Just to get the fuel to the CP3 and it will take what it wants. Which is where the by-pass came into play, it's not being force fed, just circling by it.

Like stated above, do you think it's possible that I don't have enough restriction on the return?

 

You don't want any real measurable pressure on the return line. It should flow freely.

Andy