Chris... I can shed some light on exactly what you experienced because my oldest son went through the same drama last fall between Thanksgiving and Christmas. The only exception is that he did not have a Carter booster pump installed ahead of his stock pump, and he was initially using a small "pocket" filter ahead of the pump.

Fast forward... we had to replace his pickup foot because it had completely crumbled apart and was creating line pluggage problems. The extra strain this pluggage placed on his stock pump killed the pump (something like 315K miles on it). With clean lines, no filter, and the original stock pump, we would see 60 psi until we got on it, and then the pressure would drop to 30 psi. We replaced his pump and installed a spin on filter, and the world was great again.

More context for the point I'm trying to make. On my own truck, I've been running a spin on Baldwin element ahead of a Carter pump, both being between the tank and the stock pump. With new filters, I see almost 70 psi at the engine during idle due to the extra 5-7 psi gained from the Carter pump on the suction side of the stocker. The only time I have ever experienced fuel flow issues since installing this setup was when the first Carter pump died after about 80K-90K miles on it, during which time the stocker was puling through both the Baldwin and the dead Carter pump, and I was still doing fairly well at highway speeds and up mild hills.

My point is that you may have some crumbled pickup foot junk inside your tank, but I would suggest that it may also be either an inadequate built-in priming pump or a weak (dying) stock pump (assuming that you are still running the stock pump).

Personally, what I have taken from all of this is that I'll be switching out my current Baldwin setup with the Racor setup pictured by Rich.

 

Pete,
I get what you are saying and agree that if i had not already done the in-tank mods, the restriction could be attributed to pieces of the old pickup foot clogging the line.

What im saying, is that i observed over 10psi in pressure loss with the spin on in play.
With it bypassed... my engine is 100% happier.

I keep scratching the rear wheels now that its getting that pressure back.
My throttle response went from ok, so-so... to... Holy Cow!

I understand completely the logic behing replacing the mixing chamber screens with something else before the pump... but if restriction is one of the symptoms were trying to cure with the hutch mod(as well as nullify any air intrusion) then logic asks me to answer why on Earth we would introduce the avenue for further pre-pump restriction...

For a little comic relief...

Its kind of like whipping a dead horse because he wont pull the plow...


I have no issue with your remedy to the issue...
But in my case, i dont think its worth the extra effort.
For the most part i get very clean fuel, from the same pump, pretty much every time i fuel up.

Ted and I both discovered that our local Murphy's dispenses some dirty, filter blackening light crude... so for Motorbug... Valero has the go juice.

I dont fuel up anywhere else.
I like things to be consistent.
If I get bad fuel, i will know exactly where it came from.

Again...
Im not trying to sway anyone into a fuel system reconfigure, nor disuade anyone from installing a pre-pump filter as part of the hutch mod...

Im only reporting what I observed and sharing the decision I made based on those observations to eliminate the pre-pump filter on Motorbug. She is just a happier truck running "without no panties" .

Yup...
I just went there.

 

My turn. Hutch mod and brand-spankin' new OEM pump on the stage II injectors. Verified no air in fuel (you can hear it in the fuel bowl when it's there... I have practice at this). I started with this:



It ate my... well... more to the point Stinky's breakfast. When I got on it, my FP dropped south of 20 PSI. I swapped to what you see in the first picture, and the race tune can eek FP down to 42 PSI for just a second, but that's as low as she goes - then it climbs back over that 45 PSI minimum I like.

You're not crazy, Chris.

 

Aww come on Brother Rich...
Supposed to keep that on the DL lol!

Glad im not in my boat by myself tho.

 

P.s.

Somebody get Rich for me...
Got cuffs on.

 

With the pre-pump filter in my signature and the original fuel pump, I'm seeing 58 psi at idle and about 54 at WOT. The filter was designed use on either the suction or pressure (60 psi max) side. I have the 30 micron element installed on it, but they have a water coalescing 150 micron element. I might switch to that one when it eventually gets replaced. There are a lot of options available for this particular filter housing, like heaters, pre-screens, lift pumps, primer pumps, etc.

 

Chris,

I understand everything you've shared. The only point I was trying to make is that your OEM pump is probably getting tired as is evidenced by it being so much happier without any suction side restriction (aside from the screen inside the OEM pump). A new pump would likely eliminate that situation completely.

I have to admit, too, that I do not have a readable gauge in (or near) the cab, so I cannot see pressure drops associated with WOT. When my son sold his truck, he kept his long hosed diagnostic pressure gauge for me to have/use as a troubleshooting tool, but I haven't picked it up yet. I'll do that soon and install it just to see how much pressure I lose at WOT.

 

The downside to this of course is the screen on the inlet of the fuel pump may become clogged, at which point you buy a new fuel pump. The reason I'm running a 100 micron inline filter is to catch whatever might show up in the tank to save the fuel pump. It's much easier to carry around a $2 filter than a spare pump (but after my last Carter pump failure I carry a spare pump too, but that's another story.)

 

OK, Chris... you're the first one I've heard refer to a Carter pump failure (besides me). How many miles did you get on it? The life I got out of my first one was around 80K-90K miles, and it was a little over a year ago when I replaced it.

 

Miles or weeks? I got about 8 weeks out of mine.

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

I average anywhere from 500 to 1000 miles a week, so this was long enough for it to not be an immediate failure due to a manufacturing defect absolute catastrophe, but quick enough that it obviously was.

They did give me a new one for free, but not until I had gone to the closest parts store which happened to be Oreilly's and got me a pump that would get me home.

The Oreilly pump is still running strong today, and the Carter is behind the back seat new in the box just in case.

 

My OEM was still working after 265,000 miles (note all those digits)... so OEM was the replacement (from Clay). I have the old one for backup, but I'm reasonably sure that's just going to be ballast for years to come. One and done... I have other things I'd rather do than play Musical Chairs with fuel pumps.

I forgot to back up Chris's fuel pressure at idle... I have those same numbers, and the dip below 50 PSI doesn't occur until I really get on it.

I must stress the importance of the FP gauge on our aging trucks... it really got my attention as soon as I installed it, and I felt silly for not doing it sooner.

 

Chris, I just read through your other thread and discovered that you and I are talking about two completely different Carter pumps. Yours was an OEM replacement, while mine was/is the P4594 booster pump which is running between the tank and the OEM pump.

 

On my SD I have done the in tank mods, 3/8" line from tank to engine, regulated return with bowl delete, Baldwin BF1212 pre-pump filter (20 micron water separator), Baldwin BF7633 post pump filter (2 micron), and the bone stock OEM fuel pump with 172k miles on it. My fuel pressure is a solid 60psi at WOT with 160/100s in it. I can barely see the needle flicker a tiny little bit when I stab it, but it holds right there at 60psi.

In my OBS I run the stock pick ups in both tanks, the stock selector valve pre-pump, stock fuel lines up to a Dahl 2 micron pre pump filter, aeromotive 100 micron post pump filter, and regulated return with bowl delete. With a stock SD pump I would see about a 15psi drop @ WOT. Now I replaced the pump with a Walbro and fuel pressure is rock solid at 60psi with 160/100s.

Just saying, the correct pre-pump filter shouldn't be a restriction problem... Hell, my OBS will run and drive without even having the fuel pump running, so I'll go out on a limb and say there aren't any serious problems with that fuel system.. I haven't had a pump fail or lose power on the SD yet to know if it will do the same thing, but I imagine it probably will. If you're losing pressure by having a pre-pump filter, you need to free up the system somewhere else IMO. I've done quite a few fuel systems and never had pressure issues caused by a pre-pump filter.

 

From your description, it sounds like you certainly know how to manage a fuel system setup. However, might your microns be opposite what you stated? I always understood that it is more typical to use the coarser filter on the suction side of the pump with the much "tighter" 2-10 micron element on the discharge side.

Otherwise, I would agree that there appears to be some other restriction (or pump performance issue) in Christof13T's system.

 

Nope, I posted it absolutely correct. On my OBS I installed that Dieselsite CPR fuel system about 5 1/2 years ago. That is the arrangement that the fuel filters are in. The 2 micron Dahl pre-pump filter is also a water separator. Even I find that fuel system arrangement to be odd, but I can't say anything bad about it because it has worked very well in my truck all these years. That is the only system I've ever installed that wanted the filters arranged in such a way.. There are quite a few things about the Dieselsite system that is different from the "norm".

The regulated return doesn't feed at the front or rear of both heads like has become normal. It feeds at one head, feeds through that head, crosses over to the other head and feeds through the other head, then returns to the regulator. I prefer feeding fuel at the front of both heads, but I haven't had any issues to give me a reason to replace that fuel system. I'll be replacing that fuel system when I put some bigger injectors in it that will also require a big Fuelab pump.

My SD has the fuel filters arranged like you're talking about in that post.