Deuce Billet Dual Fuel Filter Assembly

[lino]

Hey All,

I'm working on a fuel filter setup for my deuce.
I made some hints about this in one of my threads, but I figured I could put it all in one "development" thread. That way I (and others) have an easier way of keeping track of all the useful comments.

Couple pics of the CAD design to start:


The system will bolt more or less in the stock fuel filter location, it has an integral (and adjustable) pressure regulator, dual gauges (pre and post filtration), and keeps all the fuel lines on the same side of the body (the side that's closest to the IP).



Here's a couplel pics of a 3D printed part to check for approximate fit.



Finally got around to making revisions based on 3D print and started the programming and machining.

More soon.

 

[lino]

Here's another pick that's see thru and has all the bits in the picture.


Hopefully, with some head scratching, you can see how it works...

 

[lino]

Argh. I keep finding stuff to add...
Another pic of the fuel system, really helps visualize what's going on...

 

[lino]

So, after some (successful) testing on rigid pipe tapping earlier this week, I got started machining today.

Before and after the first operation (top surface):


This is after the second operation. That drill bit is 8" long and I used every bit of it's length. (wishing I had thru spindle coolant!!) And I was close, my machine only had 3" of vertical travel to spare.


This is just after the start of the fourth operation (front face), and after that op was finished:


And before/after the fifth (and final) operation:



And that gets everything up to date.

I'm hoping to machine the steel inserts for the filters today, and start fitting all the little bits together. I'll get pics of how that's going later (if I can get to it today)


ciao
lino

 

[lino]

well, if I may say so....
I'm feeling a little smug. It went right together:


The filters are just sitting on top in the last pic.
Getting started on the threaded inserts for the filters now, while I have momentum...

If I can get the mount bracket done today, I might get testing started this week.
(does anyone have the hole pattern of the studs in the block that the stock setup mounts to?)

thanks

ciao
lino

 

[59apache]

very nice machining

 

[Snowtiger]

Correct me if I am wrong but that same configuration would work as a replacement for the fuel cartridge style water separator on my M923A2 behind the front wheel wouldn't it. ??. Excellent workmanship by the way sir

 

[lino]

I finished the threaded inserts today:


And with all the bits together:


So now all that's left is the bracket to hold it to the vehicle. That'll probably have to wait until the weekend, and I'll install the works at the same time.

ciao
lino

 

[rustystud]

That is looking really nice lino ! Keep track of your time and materials as I might want you to make one for me !

 

[Ferroequinologist]

That is cool. Sometimes I wish I had taken machine tool classes in school.

 

[Valence]

I'm a big fan of the built in gauges, and fuel flow labeling on top (More pictures of those!). Top notch work for sure! I'm with rustystud on wanting one!

 

[wreckerman893]

Any idea on cost for a complete unit. I only have one deuce left but the aftermarket system I bought for it is FUBAR.

If I decide to keep the truck (M275) and restore it I'm going to make several improvements on it.

Keep us posted on mass production and prices.

 

[lino]

So, I'm amenable to selling these, but I want at least one more iteration on the design first. Not sure what the price will be. I'll certainly post in classifieds when I get there. I can bound the price between $200 and $500. That's a big range, and it'll hopefully be on the lower side. But these take a fair amount of work to do. Anyway, more on that later.

Here's some pics of the install:


And so now I have some questions...
My intank fuel pump was dead (just died 2 days before) when I installed this, so I had to replace that before I could test.

Got the Parker pump in this morning and it works great. Runs about 9psi on the gauge on the tank.

Thanks to gringaltube for suggesting a prime port, as that made things quite easy. Took about 30 seconds for a mess to erupt out the port. Capped off quickly and easily.

Engine started right up.

Now, next I needed to try and adjust the overflow valve...

with the valve where I had it, mid tight, it read 40 psi at idle. As I turned down the valve, nothing happened for part of a turn, then the pressure started dropping, linearly with turning the adjust screw.
So far so good. Valve was seated shut above system pressure, and I could turn it down and it appeared to regulate smoothly.

I put the valve back to about 1/2 turn above seated (that is, I turned it up till the pressure stopped rising, then went 1/2 turn further).

Next I revved the engine. As I revved, pressure rose to maybe 50 psi or so.
I'm not sure how high I revved it, but at some RPM (don't know if it was near red-line), the pressure would suddenly fall, maybe 10-15 psi. Then it would go back to where it started for about a second or two, and then repeat.

I couldn't hear any change in the engine revs, and I didn't do it very much, so I'm still not sure what was happening.
Is there some sort of fuel cut at redline? It doesn't seem like my overflow valve would do that, since it regulated smoothly while I adjusted it.

This seemed like some kind of really sticky or poor fuel pressure regulation. Of course I didn't have gauges before, so I can't tell if these filters are the culprit...
Haven't driven it yet.

I'll re check the TM for the fuel pressure settings later this week and get the valve set a bit better. But I was wondering if anyone had an explanation for this?
I might be able to post a video of it tomorrow (if it does it again...)

Thanks

ciao
lino

 

[rustystud]

Your relief pressure should be 70psi at around 2200rpm . Probably what was happening is your relief valve was opening and closing at 50psi , though why all the pressure would drop to 15psi for a second I don't know. Maybe your gauges are slow to react .

 

[Tracer]

Count me in for one.

 

[peashooter]

Very nice

 

[lino]

OK, so I managed to do a little more testing today...

Rustystud was correct. The relief valve was set too low.

I had it set, at first, so that it just stopped regulating fuel pressure at idle. That's not the right setting. Fuel is regulated elsewhere (at HH), and this is just a secondary bypass to knock the top off of occasional pressure spikes.

So it makes sense that things went weird if set too low. As system pressure rose, my regulator started dropping pressure, but the main regulator would still be increasing it, then they start fighting, and I end up with weird oscillations...
So what I saw was easy to explain.

Here's a video of the issue:
https://youtu.be/ZKIiW_vkqIA

Now, as to adjusting it to the correct setting...

For starters, I checked travel. There are almost exactly 4 turns from where it stops regulating at idle (40psi setting) and where the screw bottoms out.
For lack of a better starting point, I went 1 turn further in from 40 psi.

When I ran the engine up to 2200 (and also 2500) RPM, there were no other issues. Pressure rose to about 60 at 2200 rpm and almost 70 at 2500 rpm.
No more oscillations and the gauges were steady.

And a video of after the adjustment:
https://youtu.be/8pN-smNb6fI

With 3 more turns of the screw before things bottom out (I don't know if that's thread travel or spring at full compression), I do know that there is still room for the ball to relieve excess pressure in the event of a spike.

Only thing left to solve now is that I'm a little uncertain that the screw will stay where I put it.
I'm going to replace it with one that has a nylon insert in the threads. That should provide enough friction to stop it from moving. I don't have enough space in there for a locking screw.

Other than that, so far anyway, all seems good. Going to fix a couple tap depths here and there on the next version, but nothing major. I might add more engraving to indicate which way the fuel flows thru the filters (which one first), and also identify the vent port and the bypass adjustment access port.

ciao
lino

 

[lino]

I'm tweaking the engraving on the top surface. Here's a "wordier" option:

Hopefully it's readable if you expand the pic...
(some of the lines look dotted, they aren't, it's just the pic)

Any comments? Too much? Not enough? Unclear? Missing anything?

Thanks

ciao
lino

 

[rustystud]

I'm tweaking the engraving on the top surface. Here's a "wordier" option:
View attachment 585692
Hopefully it's readable if you expand the pic...
(some of the lines look dotted, they aren't, it's just the pic)

Any comments? Too much? Not enough? Unclear? Missing anything?

Thanks

ciao
lino

Looks good to me ! Actually looks like military grade ! Just like the wire diagrams on the MEP's .

 

[Valence]

Man I love the "wordier" version. Helps folks like me

First Question:
What does RLF mean? (RLF Adjustment)
Relief?

If you sell these, include in your price a creation of perhaps instructions such as for adjusting or what pressures should read.

Second Question:
Are the pressure gauges displaying the pressure AFTER or BEFORE each filter? (It might make the top too cluttered if you tried to include that clarity in the arrows - or maybe not if you're clever