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Discussion Starter #1
Well, after getting almost done, after I installed the boost gauge, which went ok, I have the FP gauge (autometer electric) screwed in to the banjo bolt. I plugged the harness into the back of the gauge and ran my hot and ground for the lighting. I started it up and the gauge went to 9 psi and stayed there. I then revved the engine up and still stays @ 9-10 psi. Any ideas on what may be causing this....did the standard checking the ground and what-not...

I also noticed that the autometer sending unit does not screw all of the way into the banjo bolt..it gets tight after about half way or so. I checked for leaks and all is ok as far as that goes..

Any ideas guys????
 

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I wouldn't think it would move until you revved it out while you actually have load on the engine....not just in neutral. What does it do when you lay into it when you are driving?
 

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I have not drove it yet because i still have the pyro to install so I have wires everywhere...I haved revved the engine though and it pretty well sits at 9-10 psi...does this sound right as far as amount of pressure or should the gauge be moving up and down as I rev the engine???
I wouldn't think it would move until you revved it out while you actually have load on the engine....not just in neutral. What does it do when you lay into it when you are driving?
 

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I would not run the sender directly into the banjo bolt. I have heard that the engine vibrations are tough on senders. I ran a grease gun hose from the banjo bolt to isolate the sender. At the end where the sender screws in I used PTFE paste instead of tape to keep pieces of tape from pealing off and cloging the sender and also connected a T so I could run an idiot light in the guage mount to grab my attention if fuel goes below 5psi. The sender was an off the shelf Cummins unit from a Freightliner dealer... $13. Dont use automotive fuel senders as they are not rated for diesel and will melt internally. Good Luck... Chris
 

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Sounds like it is working to me. What were your expectations?

On my Autometer gauge, the sending unit had 1/8 NPT threads. This is a tapered thread, so what you describe seems correct.

9PSI on a stock in tank lift pump doesn't seem off. As a previous poster said, take it out and see what FP does when your boost gauge is at 30PSI.
 

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Discussion Starter #6
honestly, I am as far as away from being a mechanic as possible, so I honestly do not have the knowledge to know what the characteristics of the gauge should be, as far as what pressures and needle movement, etc...

I am just trying to verify that I installed it properly...
Sounds like it is working to me. What were your expectations?

On my Autometer gauge, the sending unit had 1/8 NPT threads. This is a tapered thread, so what you describe seems correct.

9PSI on a stock in tank lift pump doesn't seem off. As a previous poster said, take it out and see what FP does when your boost gauge is at 30PSI.
 

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I am just trying to verify that I installed it properly...
For your truck with a stock in tank lift pump, if the sending unit is not leaking fuel, what you describe sounds correct.

You will probably see some lowering of fuel pressure when you put a load on the engine. Boost follows fuel, so if you are seeing 20-30 or more PSI of boost, your engine will be drawing max fuel, thus drawing down the pressure.
 

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Discussion Starter #8
Dad- thank you for your help. I just did not know what to expect. I did not know that the gauge is fairly steady in movement. I didn't know if it was supposed to bouce around like a tach or what....I also just got off the phone with Autometer tech support (they were excellent) and they told me what psi to expect with my engine and verified over the phone that I installed it correctly (as much as they could anyway while being on the phone).

Anyway, thanks a million and know I move on to the PYRO tonight. Little nervous about drilling!
 

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Good thread, good info here guys, thanks.:thumbsup

Kevin
 

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I will try to update tomorrow after I do the pyro tonight...

Hopefully I can get that done and buttom up all of the wiring so I can pick up my boat and de-winterize it this weekend...My truck is a disaster with the wiring and dash apart right now!!

Supposed to rain tonight so i hope I am able to get it in....unfortunately, my garage is not quite big enough to do the work in:CRY:
 
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