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Yes that sounds low for the work done. overflow valve could be the culprit. Punch the return line for a second and see if the pressure spikes. If so the OFV is bad.

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it was only 19psi I max out my overflow valve.
What do you mean by this? Do you have an adjustable ofv or did the pressure drop to 19 psi when you increased the rpm to 2500
 

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If the pressure is 24 at idle the OFV sounds fine. What is it at 2500, no load on the engine? It should be higher. Dropping pressure at WOT while driving indicates a problem of fuel delivery.
 

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Yes that sounds low for the work done. overflow valve could be the culprit. Punch the return line for a second and see if the pressure spikes. If so the OFV is bad.

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If you pinch the return line when the engine is running the pressure will spike if you have a good or bad OFV.

Pinching the return line to check to see if the truck will start on the first crank tells you the OFV is bad if you've had starting issues.
 

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Discussion Starter #25
Yes I have a new torktek adjustable over flow valve. My truck has 0 psi fuel pressure at 2500psi wot. My lift pump must be junk it's not that old probably has 50000miles on it. Also has heavier spring in it. these lift pumps seam to be junk anymore I got this one from genos garage.
 

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WOT while driving is not 2500 RPM unloaded. If you want to drag out the process of troubleshooting for days just keep not answering the questions. Genos sells genuine Cummins lift pumps, they don't make them. Yours might be faulty, it happens sometimes. However, just like a new vehicle, once you modify it you become the warranty station. You can't blame Cummins for a pump failure after you opened it up and modified it.
 

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Discussion Starter #27
In my truck 2500rpm is wot wont go pass 2500rpms. How am I not answering the question. The truck has 0 fuel pressure and that was with the truck loaded not unloaded.
 

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Discussion Starter #28
It was both loaded and unloaded. It really has 0psi even before I get to 2500rpm. As soon as i smack the throttle a little bit u can see fuel pressure drop off quick.
 

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Pretty simple then. You need a new lift pump.
 

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This is why I have stayed off this site for the last 6 years.
I took a look at your last post from 2014. So tell me, do you still believe this?

. Your boost lines going to your boost gauge have like a 3-4mm inside diameter (I'm just throwing that number out there) however, psi=pressure per squar INCH not PER MILIMETER. When a 1 Inch line will lift 40lbs of weight when charged to 40psi, your 4mm boost gauge will lift, well lets see. 25.4mm per 1 inch. So math: 4÷25.4 will give us what percent difference it is between a 1 inch hose and a boost line. So 4÷25.4=0.1574 or 15.74%. So your boost gauge is 84% (100%-15.74%) smaller than what PSI reading are suppose to be measured in (a 1inch hose).
Games you are too funny. I wonder how long you spent looking for this. You won't read how a turbo works but you will spend hours looking for dirt. Reread the post. I wrote this in the correct context of what the poster was asking.

As for the fuel psi issue. It does sound to me like the lift pump is bad. Another thing I have seen is using the wrong fuel line from the tank. The lift pump will actually draw enough suction to collapse a weak fuel line. Last I saw this a guy was running 1/2" heater hose instead of fuel injection rated hose. Anyways, just another area to check.
 

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I wonder how long you spent looking for this.
Not long. Maybe 10 minutes. Totally amazed that PSI can not be applied to a PSI gauge because the line might be 4.6 cm. Would you feel better if it was 1/8th inch? Oh, I already know how a turbo works. Trained on gas turbine engines, remember? Same principle, add air plus add fuel = more power. Add air alone, cooler EGTs, add fuel alone, higher EGTS and smoke.
 

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Games you are too funny. I wonder how long you spent looking for this. You won't read how a turbo works but you will spend hours looking for dirt. Reread the post. I wrote this in the correct context of what the poster was asking.
It's actually pretty easy, a matter of seconds really:

Click on Username > Find More Posts by [user]. Newest posts appear on top. Skim past the couple dozen or so 2019 posts, and there it is at the bottom of the second page (currently).

There's nothing to re-read, you clearly didn't understand the difference between pressure and force when you made that post. Boost gauges read/show pressure, not force.

I will now invite you to quit trolling other members. This is not a suggestion.
 

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Yes I have a new torktek adjustable over flow valve. My truck has 0 psi fuel pressure at 2500psi wot. My lift pump must be junk it's not that old probably has 50000miles on it. Also has heavier spring in it. these lift pumps seam to be junk anymore I got this one from genos garage.
Some people get 300,0000 where some get to change them 4 times a year. I dont understand it either.
 

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My lift pump must be junk it's not that old probably has 50000miles on it. Also has heavier spring in it. these lift pumps seam to be junk anymore I got this one from genos garage.
Check the spring to make sure it isn't broken. I think you could also have a flow restriction between the pump and tank
 

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I did a failure analysis a few months ago on one. Owner sent it back saying the fuel pressure dropped to zero out of the blue, all the sudden. Turned out the discharge check valve had disintegrated. Newer (current revision, Chinese manufactured) pump, about 3 years old with 50k or so on it, as per the owner.

Nothing mass-produced is perfect.
 

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I did a failure analysis a few months ago on one. Owner sent it back saying the fuel pressure dropped to zero out of the blue, all the sudden. Turned out the discharge check valve had disintegrated. Newer (current revision, Chinese manufactured) pump, about 3 years old with 50k or so on it, as per the owner.

Nothing mass-produced is perfect.
Could biodiesel have any affect on the valves.
 

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It's surely possible. The checks looked and felt like a bog standard 75-ish durometer Buna-N which would not be the best choice for use with bio. The inlet check was in perfect shape though, so I was left with the assumption there was a chemical defect in the one that caused it to fail.

A company like Cummins could easily have pistons supplied by one place, outlet fittings supplied by another, castings supplied by yet another, then carry out assembly at a separate location. If that is the case, and each manufacturer is on their own for sourcing materials (not an uncommon practice in China), it'd be a near certainty that the two check valves aren't coming from the same molding plant.
 

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Change your fuel filter, check for plugged fuel heater, before you waste money on a new lift pump.
 
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