So I went with the Lunar Series gauges (wanted to match my inside lighting) and I bought them a while back. I finally got the fuel pressure gauge hooked up and it is showing a constant 16-17psi or so. It doesn't drop with my comp box on 5x5 at WOT at all. I do have a FASS.
Ok, so the reason why it bothers me is what it says on summit racings website now on that gauge.
"This gauge is not designed for use on a Dodge diesel." (didn't say that when I bought it)
I don't want to mix/match my gauges and I sure as hel don't want to replace all my gauges ($$$) but I need to know if the reading is accurate. Why would it say that about this gauge?
The sender is ran inline at the vp44.

 

Link to gauge

Summit Racing Autometer Fuel pressure gauge

 

Dont know if they say that because its the wrong range....or maybe it will not withstand the pulsations from the fuel system in the Cummins. Have you called Autometer tech to ask??

You can check it with a mechanical gauge on the test port of the VP-44.

You can get the hose for a test guage here:

http://www.vulcanperformance.com/ser...ies/Categories

or from Genos:

http://www.genosgarage.com/CoastalDa...ectGroup_ID=98

 

Does the gauge go up and down when it primes with the key?
If it goes up and down after the WTS light then I would say the gauge is working.
I have run AM gauges in both my Cummins and had no problems, I ran a liquid filled pro comp 0-15 fuel gauge (I ran that same gauge for 10 years on my gasser) for around 3 years and on this truck I run a 0-60 liquid filled blower pressure gauge.

 

ratsun...same thing I am running on mine....60 psi blower gage.

My guess would be the pressure pulses will kill it. Call Autometer and ask them.

 

I don't think it moves. I will double check though.

 

When I first started experimenting with FP gauges on CTDs about ten years ago one symptom of failure I saw with electrical gauges is that they would often read just the highest pressure they have seen and zero with no in-between.
Very deceptive mode of failure that leaves you with the impression that everything is fine. After several sender failures I gave up and went mechanical, no problems at all.

 

The pulsations from the vp44 can kill senders very quickly (I went through 3 with my digital gauges) and autometer probably doesn't wanna keep warranting the senders because of that problem. So install a needle valve and you'll be alright.

 

Ditto on the needle valve......it will just about completely cancel out the damaging pulsations to the sender.

 

myautometer sender is an small electric unit that screws in...not one of the large brass or metal units with studs for connecting your electric FP gauge to. this was a new style i bought a few months ago that uses a wiring harness with special plugs...and my FP gauge is all over the place. i assume its the pulses of the VP44 but its fluctuates alot, which is good instead of just reading the highest pressure like mentioned above. I have the sending unit in my "big line kit" about a foot from the VP44, so i may still add a needle valve to eliminate any pulses...but I just worry about my low readings.

 

I guess the difference is if you use a Mechanical gauge you dont have a sender to fail, and if you use a liquid filled Mechanical gauge it helps to dampen the pulses that may hurt the gauge? As stated though a needle valve is a must for safety.

 

Ok so a needle valve... where do I get one and where exactly does it go? I have the sender plumbed in right befroe the vp44 but as far as pusations, my gauge shows none. It never moves from 16-17. I would just go with a mechanical one but they don't offer it in Lunar and I want them to match.

 

The needle valve can go anywhere in between the pressure source and gauge (mechanical) or sender (electrical)
The valve should be run barely cracked open.
They are commonly used on ice makers and are available at most hardware stores.
Napa also carries them.
A male/female configuration is best so no additional fittings are required.
I buy mine here http://www.grainger.com/Grainger/wwg...835462&ccitem=

 

I run the Diprocol gauges, and LOVE them. These are the poop. Get rid of that autometer junk. Those are for the hot rods. Run the stuff for Diesels.

Actually I got these because of the boost gauge. It was the one I really liked, and it had the best possiblereadings. 0-30

Dima

 

Ok so the source of pressure is the FASS right? I thought it was from pulses from the vp44?

If its barely cracked open, wouldn't that seriously disrupt the fuel flow to the vp44?

Thanks Dimirti, I'll check them out!