Banjo fitting and fuel pressure gauge

[wscott]

I'm in the process of acquiring all the necessary parts for some gauge installs. One of the gauges is the Westach fuel pressure. I would like to use a banjo fitting but am unsure as to where to install it. I'm assuming that it goes at the bottom of the fuel filter bowl. If this is correct, at that location is it pre or post filter? If this not the correct location, please HELP. Thanks in advance for any help you may render.

 

[wscott]

P. S. If I wanted pre and post pressure readings where would the second sending unit go.



Also, the kits at Geno's come with some standard banjo fittings. Why would you need these? I'm assuming that you would remove a factory banjo fitting and install the tapped banjo fitting. Is that accurate or am i missing something?

 

[dmurdock]

Just a guess, but the one's your seeing may be the increased internal diameter banjo fittings. One of the common mods on the vp-44 motors (98. 5-2002) is to upgrade the fuel system... the new banjo bolts are supposed to flow more fuel than the stockers.





If your installing one unit, definately install it post filter. If it reads low, change filter. Still low... check the pump. (no way to tell filter condition pre filter).



I don't know if there will be as many fuel guage install experts on the 03's... there was definite hysteria involved with the vp-44 motors (i had 2 of 'em). The fuel system on those trucks was marginal at stock levels... the fuel system on the 03 seems to be OK for up to around 400hp (or so I've read... only time will tell).

 

[DIESELMAN]

Isn't a fuel press. guage on an G3 a waste of time?



If the engine runs, theres enough, and that doen't mean there is enough pressure to even measure between the lift pump and primary of the fuel pump.



Besides the Low side of the fuel pump is sealed between it and the high pressure side so theres no way to measure that either.



If the engine runs, its primed, and the lift pump has no further task in life. And once running, you should be able to pull the power to the lift pump, its electric, with no effect. The Fuel pump just draws fuel through the lift pump, whether the lift pump is running or not. It will start and run just fine even without the lift pump running if the pump is primed.



In fact, I would expect under heavy throttle, the pressure would be negative, vacuum, as the fuel pump is exceeding the ability of the lift pump.



So I think the fuel pressure guage isn't necessary.

 

[rbattelle]

If you do install one (and there are people in here who have done so and can provide good advice on where/how to do it), just be real careful if you do it post-filter. This new fuel system is SUPER sensitive to dirt/contamination.

 

[Car_nut57]

Fuel pressure gauge

At the bottom of our gauge page http://www.dieselpowerproducts.com/gauges you will find PDF files of gauges instructions for the 03 Cummins which includes the fuel pressure gauge. I hope this helps to answer your questions.

 

[d90boy]

The new TDR issue indicates that lift pump fuel pressure is insignificant, that is only there to prime the main pump. The Duramaxi has no electric lift pump supposedly. Anyone read about problems in the Chevy forums about burning up high pressure pumps with increased fueling? DD says we need a supplemantary pump and lines over 400hp. I wonder if the stock lift pump becomes a restriction at high fuel levels with the high pressure pump trying to pull more than the lift pump can flow? Maybe KLock will see this and tell us why we need the supplemantary fuel line/pump kit.

 

[wscott]

Thanks guys. All your help is greatly appreciated but what I'm really after is a picture showing the banjo fittings that would need to be used/changed out to allow for pre filter and post filter monitoring. Hope someone can help.

 

[AndyMan]

Unanswered Questions

This thread leaves some unanswered questions. I too have a Fuel Pressure gauge on the way, and am not real sure of how to tap into the fuel system. Will a tapped banjo from Geno's work for me? What size fitting do I need to attach to the banjo bolt?



I'll be running fuel into the cabin, so no worries about the isolator.



Thanks,

Andy



Pics!??!?!?!? Instructions, Tips, etc?!?!?!

 

[rbattelle]

There's a banjo fitting on the bottom of the canister that I believe will give you pre-filter pressure. You will need to buy a banjo from Genos.



Tip: avoid smoking while performing this installation.



Ask RSnaith about it... he's done it (not the smoking, I mean the banjo install).

 

[AndyMan]

LOL! Where's the sport in not smoking!!?!?!



Seriously, It SEEMS like I saw somewhere that someone had tapped into the pump just after the fuel filter... . Seems like they had attached an isolator as well. I want to tap there... . just not sure if the banjo from geno's will fit.

 

[rbattelle]

I'm under the impression that the banjos are "universal", so the banjo you get from Genos can replace any of the stock banjos.

 

[AndyMan]

Well I'll be darn! I guess you're average idiot could've figgere'd that. I feel kinda silly that I didn't put 2 and 2 together and conclude that for myself. I guess you can tell what level of novice you're working with huh?



Thanks for the help!!! Maybe I'll get all this figured out soon!

Andy

 

[rbattelle]

Andy,



You're not an idiot, it's not immediately intuitive that they would be "universal".



Just do yourself a favor: be CLEAN when you do this job. Don't let ANYTHING get into that fuel system. If you use Teflon tape, use it sparingly. Remember those injectors are sensitive, and if one blows on you and it's not your fault, the dealer is going to see that a modification (no matter how small) has been made to the fuel system and deny your warranty.



I'm convinced that's going to happen to people at some point, and I dread the day it does.

 

[barbwire]

change of plans

Well, from what I see on this thread, I guess that I have to change my plans. I was going to put a fuel pressure gauge on my 2004, but from what I am reading here, it seems as though it would be a complete waste of time & money. I guess that I will have to put a trans. temp guage in the 3rd hole in my 3 pod A-pillar mount, Where I had intended to put the fuel gauge. Then just change the fuel filter frequently.

Oh well, the 99 needs the fuel pressure gauge anyway... ...

 

[d90boy]

If you don't want a permanent FP gauge you can replace the stock banjo bolt with one that has a schrader valve on it. I went to the dealer and bought a banjo bolt from a 98. 5-02 truck. This would let you put a FP gauge on and see what your FP is doing under full throttle without a permanent install.

 

[rbattelle]

from what I am reading here, it seems as though it would be a complete waste of time & money

In my opinion, no gauge is a waste of time or money. Except maybe a muffler bearing wear indicator.

 

[d90boy]

Yeah or blinker fluid temp gauge.

 

[barbwire]

gauge

Muffler bearing , wear indicator !!! Ok, you got me there. But, if it's like d90boy said, that the fuel pressure is insignificant in the 3rd gens. , then maybe a persons money would be better spent on something else. But, I am still waiting for the final verdict, as to the worth of fuel pressure gauges on the 04s. Because, if there is at any time a vacuum inline before the injection pump, what would you gain from having a fuel guage?

 

[rbattelle]

Overall, I think the jury is still out on whether we need FP gauges or not for 03-up. It might just take some time for the fleet to get some mileage on it.