Wouldn't I somehow see that in the data captured from the truck though?

Also, would such a tune explain the bouncy EBP, high EGTs and lack of boost?

 

Yes, by monitoring ICP, Duty Cycle, boost, EGT's, FIPW, fuel pressure in the higher HP tunes. and some tunes modify the the EBP sensor.

It's just a guess, wish I was close enough to go for a drive.....

 

Air in fuel (sender anywhere on the pressurized side) and loaded fuel filters (sender on the passenger side of the fuel bowl) are the most common causes of fuel pressure drops at WOT. If the sender is on the driver side of the fuel bowl, pressure will climb with a loaded fuel filter.

My sender is on the passenger side port, and I get a 5 PSI drop at WOT (regulated to 60 PSI). Right now I'm getting a 10 PSI drop because my fuel filter is due to be changed out.

 

Good Info. I have the gauge plumbed into the driver side of the fuel bowl.

The video was done with a full tank of fuel.

The fuel filter was changed out recently.


So the pressure drop might be indicating air in the fuel?


Could this air be related to boost/egt/ebp jump issues though?

 

Yes, but should he see any drop with stock sticks and stock tuning?

 

Air in fuel will make any tune drop pressure, and depending on the severity - can cause all kinds of running problems and unnecessary noise in the injectors.

 

I'm trying to figure out what to do next. I'm going to take one more spin on an intake and/or exhaust leak and expect to find nothing.

Based on my symptoms, it seems like there are 2 paths I can go next. One is to deal with possible air in the fuel and the other is to do the injector o-rings.


I think o-rings would involved
1) Compression test
2) New glow plugs
3) new o-rings

Can I send the injectors out to have them bench tested? It seems like if one is misbehaving and causing all these issues that I might not be able to tell which one it is with a visual inspection...

 

Air in fuel abatement is an absolute must!

Regardless of what else you may fix and find, your truck will thank you for it

Keep in mind that air in fuel will still allow you to build pressure, just unsteady pressure. Why? Air compresses, liquid fuel does not.

Like trying to drive nails using a hammer with a spring on the head. Yep, just as noisy and chaotic...in your fuel system and your injectors

PS- I've also read about people finding rusted fill and vent tubes when dropping their tanks, so be sure to check and replace as necessary. Your pump will thank you

 

agree 100%, this type of mod is a must do IMO weather or not it is part of your current problem. A kit like this is a great option.

https://www.strictlydiesel.com/p-266...hutch-mod.aspx

************************************************** *************

 

1) If I go through this process, I'd like to install a filter where I can see if there are bubbles (or gunk) in the fuel. What about a a Parker (Racor) PS12-02 filter?


2) If I install the filter first - while I run down my 44 gallon tank of fuel - shouldn't I be able to see the bubbles/foam in the fuel if that's an issue?


3) It looks like there are hard lines from next to the pump to the gas tank. Do people cut these lines and add a compression fitting and hose barb to plumb in the filter?


[ EDIT ] OK it appears as if some people just replace the hard like with a rubber hose. Has anyone retained the OEM hard line without cutting it? [/EDIT]

4) I keep reading that the hutch mod fixes a an air in fuel problem at less than 1/2 tank. I did this pressure drop test with a fresh fill.... So does that eliminate air in fuel as a candidate?


[EDIT]
Could my higher RPM loss of power and higher EGTs be caused by clogged filter in the tank?

After some reading I'm learning the higher EGTs is related to more fuel (as opposed to a lean condition). So I wold think that clogged filters in the tank would result in less fuel so low EGT and low power?
[/EDIT]

 

I'd recommend doing the Hutch/Harpoon mods in a pretty traditional way. No sense reinventing the wheel. Guzzle's Hutch Mod Read thru that and google other threads to get an idea for how it works and what your choices are.

The Strictly Diesel kit Rich linked above is very nice but you can get all the parts yourself for less. The filter that comes with it is overkill IMHO, but many run them just fine. A simple strainer is all ya need down there, and some like the Baldwin BF7725. That Racor is BA. Search for threads like this one and you'll see plenty of options.

You will want to run the tank down close to empty before you go to drop it, just so it is lighter. You could also siphon the fuel out.

For diesel less fuel is less power, more fuel is more power. Assuming adequate air and proper timing. Not like a gas engine where a lean mixture burns hotter.

Also, that video of the fuel pressure dropping after pump is turned off is freaky. A quick 10 psi drop then a super slow decline? WTH. All the pressure should bleed off in around 2 seconds under normal conditions. Something is wrong there, but what, I do not know. Possibly just a funky pressure gauge setup.

 

Look at my video and comments here:

https://www.ford-trucks.com/forums/1...hutch-mod.html

Just use a piece of clear gas tubing (like for motorcycles) and use the pump to empty your tank. You have to cycle the key about every 15-30secs.

Bet you see air like I did...and LOTS of FOAM when you get near the bottom of the foot.

My Ex has a piece of rubber line from the tank to the hardline by the driver's rear wheel and a piece from the hardline into the fuel pump.

Yeah, that's what I thought, too

There is also a duckbill that fails and allows air into the system, above the pickup tube.

Edit: Also the quick connect hose fittings on the suction side often admit air into the line, hence the recommendation to replace those rubber lines on the INLET side of the pump. More debate about the outlet side

Inefficient combustion due to unstable fuel/air ratio can do strange things.

Seems strange that gassers add fuel to cool EGTs, but diesels are different animals.

As to the exact nature of high EGTs, that's best left to those who know more than I to explain

Hope this is helping

 

I have a line tapped into the driver side of the fuel bowel. I drove the truck for 10 min and then ran about a gallon of fuel through the system before taking this video. I ran at least 3 koeo passes of the pump with the video being the last one.


It seems as if I don't have a current air issue on suction side of the fuel pump:





I've reviewed that. I know many have successfully done it. I'm just paranoid about using compression fittings inside the gas tank. With my luck something will happen on a bridge, in heavy traffic, towing a trailer with my family in the truck.


Great link for filter options, thanks. I prefer a see through filter like the Racor. I figured for $200 I could get a replacement for the whole assembly, no such luck yet. I see that RiffRaff has a no fitting solution for $400. That's getting up there in price though.





Ha - it's got about 42 gallons in it right now... I'll have to run it down even if I decide to siphon some out.


It's just an analog gauge plumbed into the filter port. The gauge is new, so it could be the gauge, there are no leaks in the setup.


OK, as you can see in my video, I did not have a clear line. I had that small jar and kept getting air. I figured it was a startup issue. So I got a one gallon jug and let the jar overflow into the jug - so I could watch for air bubbles in the jar.

If the hose is in free air and pointing down and the pump goes off, the hose continues to drain. **I think** this causes air to be in the hose. When I kept the line in the bottom of the full jar I didn't get bubbles when starting the pump for the 2nd or 3rd time. I think this confirms my assumption?

[edit] missed the spot where you addressed this:

I know that if I left the tube submerged that I didn't get it thought.
[/edit]

Now the noise in your video at the end (~13 seconds). This is normal correct?

I could not find the line from the hardline to the tank. But I assumed that was the case. The part from the hardline to the fuel pump is very short and not clamped on. I assume some kind of adhesive. I think it's too short to remove from the fuel pump and then loop in a fuel filter right there.


The outlet side will be obvious. Since it's under pressure, and leak should present itself pretty clearly.



Yes, this is really bothering me. On the one had I have low boost, and no black smoke. As I understand it, this points to a lack of fuel. On the other hand I have high EGTs at higher RPMs under load. This, I think, implies excess fuel.

 

Here's a video of of the pump starting. The jar is already full, still dripping a little from the previous pump flow. This video ends after the start of the other one I posted, so between this one and the other it's the entire koeo pump session. The other video had some talking so I got rid of the sound.....

ExPACamper you can hear the sound I was asking about in this video at around 8 seconds.

 

Tugly, found this is ExPACampers other thread:

If you look at the 2nd video, I drop my foot and then the fuel pressure drops from ~63 to ~57. It stays at ~57 until I take my foot out of it. Is this a big deal?