Fuel pressure....but running out of fuel!

[gingrass179]

Ok guys I used to be on here all the time..i had built the crew cab with the super short bed..well I need help! And I know this is the place to go!

I traded an ar for a 89 250with the 093 turbo with 3"outlet....
We couldn't get it running there. I bring it home put in a starter and she fires right up and runs great and was originally just going to be a quick flipper truck

So I started cleaning things up

And we'll things got out of hand!

Everything has been gone thru.I even tore down the spring pack and sanded and painted each spring and then reassembled! All new bushings and new front springs with a leveling kit and new radius arm and inner beam bushings new rubber brake lines up front and the rear drop down new wheel cylinders and shoes new calipers bearings pads and rotors new e brake cables new u joints new body mounts new carpet and headliner seats from 06 250 new clutch and fly wheel

Now onto the trouble

The truck ran great when I started doing the tear down...I mean phenomenal or I wouldn't have thought twice...

I got rid if the mid ship tank and am only using the rear....I deleted all lines and ran my own....right off the tank on the frame rail I have a Carter pump. Pressure line runs up front and under engine along cross member the same way. once on passenger side I have a holley bypass regulator mounted line goes from there to filter head...I have gauge mounted on the filter head...set at 6 psi...

Truck idles and runs like a dream up to 2000rpm...around 23-2500rpm it acts like it is running out of fuel..engine Ron's sky ticket without extra input and when I let out of the throttle and it goes back down to idle it falls below normal idle catches slightly stumbles than recovers...all the mean while my bypass return and my return off injectors and filter head maintain good fuel flow and clear line from filter head to return system stays beautiful with no air intrusion and my psi never drops on the gauge....if I bump up pressure to say 15psi it will hold good to about 28-3000rpm than same symptoms occur...I deleted my by pass regulator with no change and also deleted the regulator in the filter head with no change...I'm starting to believe my metering valve in the front of the ip is not letting enough fuel in as it is being demanded...any input or ideas please throw them my way I am at a loss...and if I need to clarify our post videos let me know!


Thanks

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

 

[icanfixall]

WEll you sure have done plenty of work on this but why??? Anyway my guess is there is a line pluggage in the suction inside the tank.By chance did you remove the fuel level sender from the tank to check if the suction shower head is broken off? When these heads break off the end up being sucked into the supply line and that causes low fuel flow like you describe. Did you replace the short rubber line from the frame to where the mechanical lift pump was? What about the fuel light on the dash. Does it come on when you have these issues? The fuel light sender is located on the filter housing. then finally does this happen with the tank level around 1/4 tank.

 

[gingrass179]

Awe yes my apologies...I build my own sender's/pickups for these that have been successful in multiple trucks that I put in this truck also...and yes all new line from tank to filter head I bent a new metal line to follow the crossmember under the engine....I can't see a filter light yet as my dash is still disassembled but my gauge never reads a pressure drop and my clear lines never show signs of air just pure beautiful diesel

 

[OLDBULL8]

Could it be you have a U-Haul IP governed to 2500 RPM? From what your saying, they act like that.

 

[gingrass179]

Anything is possible it just used to run all the way up to 3200

 

[OLDBULL8]

Shoulda said that to begin with.

 

[catbird7]

hellava nice foundation you got there!

 

[sjwelds]

Fuel restriction somewhere.

Try running it out of a 5 gallon bucket of diesel hooked straight to the lift pump. or even straight to the IP.

 

[icanfixall]

If you think the internals of the injection pump are suspect try filling the filter with auto trans fluid. Run engine till you hear the change when the atf begins being used as fuel. then shut down the engine and wait till morning. then run it like you stole it. See if that frees up anything.

 

[gingrass179]

I did this but with sea foam lol

 

[hesutton]

What is your fuel pressure when at idle and when it acts this way?

Heath

 

[gingrass179]

Fuel pressure stays consistent at wot and idle whether I set it at 6 or 15

 

[hesutton]

If you're reading fuel pressure after the filter (pressure the IP is seeing), then fuel pressure/supply isn't the problem.

Heath

 

[gingrass179]

That's what I had figured...would you be in agreeance of a metering valve issue?

 

[Macrobb]

Hm... I'd try with a jerry can of fuel and gravity-feed it into the IP. Eliminate your entire pump setup. Something is wrong here, and I doubt it's the IP.

If that /doesn't/ work, you may need to pull the back end of the IP off. the big "nose" where the fuel inlet is will unscrew(there is a hex screw and keeper holding it though), and inside is a small fuel screen. If you managed to get crud into there, that might cause it. Here's the IP manual: http://www.stanadyne.com/docs/misc/99009 DB2 Manual.PDF
Still... considering the fuel filter before it, that's the /second/ thing I would check.