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Let's take the Truck!
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Just want to say it was as simple as a $24 dollar fuel filter... Old one was naaaaastyy
With the odd LP behavior i would still be suspicious or at least cautious because the restricted flow you were experiencing. Point being as I stated many people put new parts in and all seems ok until the next bout. In my opinion you should still perform a lift pump test as well and check over the wiring. Truck will run even without the lift pump active if you have good flow ip will suck fuel. I know this from experience when I rebuilt my entire fuel system after testing my wiring and harness I unknowingly left the pump unplugged and drove the truck a few miles and noticed only a small lack of power. Im glad you got the truck running and people here are glad to help but we want you to also be successful if not at least aware. Im not being negative just bringing 6.5 awareness to you.
 

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JC is correct..

A nasty (restricted) FFM element may cause the IP to starve, especially during high FLOW demands, but will not cause noisey LP operation or DAMAGE to the LP in any way, unlike a clogged strainer that will hammer a new LP to a premature death in short order..

Clogged FFM element, LP just thinks the IP is sipping tea, completely unaware that the IP may be struggling to draw fuel through the nasty FFM element.....
 

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Discussion Starter #23
Dually noted, i appreciate the concern, and from what ive noticed, the new lift pump is making the same sound as the old one, a general noisy clicking when priming, dies out when the wait to start goes out. Should i be concerned on the new pump aswell? Maybe bring it back under warrenty?
 

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My 6.5 scared a prius
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mine runs for a bit, then when pressurized it will stop until you crank the engine over
 

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The stock LP and many others dead head against pressure, so the stop pumping with no demand. Also, the stock priming function only last about as long as the Glow/WTS on a cold start.
 

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Discussion Starter #26
I know that the pump will stop on dead head, or run til WTS light is out, but is the clicking sound coming out of the new pump a normal sound? If so then i replaced a perfectly fine pump
 

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Clicking sound is normal vibration, since its mounted on the frame rail. Some of the higher powered ones you can hear them while the engine is running too.
 

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Discussion Starter #28
Ah okay gotcha, i mustof loosened it in its clamp then when i replaced all the lines and caused it to make an audible click instead of a whine which it had before, good to know i guess though, also have a brand new fuel system pretty much other than the sock, and IP
 

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Discussion Starter #29
Soo... It did it again, it ran fine after a fuel filter change, and lift pump change, it ran fine since my last post until tonight, i let it idle to warm it up and it died, still gets fuel to the filter
 

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Soo... It did it again, it ran fine after a fuel filter change, and lift pump change, it ran fine since my last post until tonight, i let it idle to warm it up and it died, still gets fuel to the filter
What was the condition of the inside,bottom of the fuel filter canister?

If it is dirty it is recommended you clean it.
What was the condition of the screen manager down inside of the bottom of the fuel canister??

The small screen manager is always forgotten about and can cause issues.

Here is a video of how to remove and replace the screen manager.
http://www.dieselplace.com/forum/63-gm-diesel-engines/21-6-5l-diesel-engine/755153-engine-shutting-off-randomly-3.html#post7520401

It sounds like your still getting air in your fuel system as well
 

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Discussion Starter #31
I didnt actually notice if there wasa filter and seeing how the bottom looked, but i pulled the new filter out and it looked as good as new, but oddly enough i waited about an hour and a bit and bumped the key and itnfired and idled. Prior to that it idled for around 3 mins and died, and just cranked and cranked. Odd, i guess i should check condition of the FFM and clean it out and replace the 2nd filter in there.
 

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I didnt actually notice if there wasa filter and seeing how the bottom looked, but i pulled the new filter out and it looked as good as new, but oddly enough i waited about an hour and a bit and bumped the key and itnfired and idled. Prior to that it idled for around 3 mins and died, and just cranked and cranked. Odd, i guess i should check condition of the FFM and clean it out and replace the 2nd filter in there.
In case you replace that screen here is the part #

Stanadyne: 29244
 

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I suspect your OPS is defective, leaving the lift pump inoperative if not intermittent. Or the liftpump is struggling, restricted or not receiving full voltage..
I know, its a '99 models but you wouldnt be the first to suffer from an inop liftpump during engine operation on OBD2 models..
I think the redundancy power thing is misunderstanding myself but I have no way to verify my suspicions first hand..


Installing a Vacuum Restriction Indicator pre-liftpump will help monitor the strainers health but wont help locate those pesky 'zippers'..

"A leak on suction (inlet) side will reduce the volume of fuel on the pressure side of the pump and suck in air."



IIRC, any more than 5" (equiv to aprox 2.5 psi) is considered excessive restriction. Currently, my recently restored system has barely registered (recorded) any measurable vacuum (pre-lift pump resistance)..
Any more that a 2psi pressure loss across the FFM element indicates excessive restriction, read due for replacement...




FWIW

Avoiding Air Intake
An important function of all hoses, lines and fittings is to carry fuel with maximum absence of air.

When the fuel tank cap is in place and the injection pump and fuel pump are drawing fuel through the lines a low vacuum of 0-1 lb. mercury is created. This occurs because the fuel which the engine uses must be replaced by air.

During this vacuum condition, the slightest leak, which may not leak fuel externally, could draw air into the system and depending on the volume of air, a wide variety of engine malfunctions are possible. These may show up as M.P.G. complaints, smoke complaints, performance complaints and hard starting or not starting conditions.

For example, suppose the inlet fitting was slightly loose at the engine fuel filter. This would probably have an external leak and be a complaint of fuel leak or smell of diesel fuel accompanied by a “ starts but then dies and can’t re-start” complaint. It is possible that when the engine is shut down the fuel could syphon out of the lines and fuel pump and back into the tank. It is then replaced by air which entered at the loose fitting. The fuel system is now empty and as a result the engine must be cranked until the lines are full again.

Continued reading on page 116
source
 

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Discussion Starter #34
I guess checking the fuel purge would be a good place to start for fuel in the line, check the pressure at the ffm after it dies, if notta is there then bleed the system and try to fire, if thats the case, then air in the line, check the left over line that isnt replaced. Im going to order that stanadyne filter tonight after work. Im reg the truck tonight, just would love it if it didnt leave me stranded again.
 

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Start with the simple and free things first
Did you open the t valve ? If yes what did it do ,if no start there
Blow the snot sock out ,take the fuel line off and take fuel tank cap off and blow air through the line
Check for fuel leaks
 

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When the engine dies, does the Service Engine Soon light stay lit with the ignition in the ON position?
 

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Whistle Pigs Are Cool
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I suspect your OPS is defective, leaving the lift pump inoperative if not intermittent. Or the liftpump is struggling, restricted or not receiving full voltage..
This is what I was thinking as well.
 
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