The Summer of Ven: Reassembling the IDI Electric Fuel Pump System

Last time I ripped most of the OEM fuel system out of the engine cave on Spool Bus, and received the parts needed to fabricate the new fuel system. So here’s where I get to put it all back together!

First things first, the new Facet e-pump itself has to be mounted. I chose to put it on the frame, right next to the filter head that some previous owner added. If you wanted something comprehensive, it seems like the R&D frame-mounted filter and pump kit is the go-to. But I already had the hard part done for me, so might as well use it!

And here it is all mounted up. At this point the fittings were just threaded in for visual effect – after I installed everything I realized some of them had to change.

So here’s what’s going on now with the plumbing. The long arc at the top is the inlet coming from the fuel tank selector valve. The fuel gathers at the clear strainer (so I can see how much poo is in it) and is sent to the filter head, then from there, to the rest of the fuel system.

This is what it looks like on the inside. It passes through the frame at two pre-existing holes – I suspect the filter head location was chosen by a P/O for this convenience. For completion’s sake it needs a plastic grommet here at the holes, which I ordered but wasn’t here yet (BURNOUTS NOW, GOOD IDEAS LATER)

With the system plumbed up to the filter outlet, time to test everything and give it its first powered break-in!

The magic van juice flows. The Facet pump makes a pretty loud clicking sound as it’s operating, possibly indicative of it being a vane type pump instead of a small centrifugal or axial flow turbine like most in-tank pumps that make a more whirring or buzzing sound.

I had this setup hilariously looping back on itself (hose back into the fuel tank) for about 5 minutes or so to break the pump in.

The remaining plumbing steps were all engine-side. I needed to cut the existing injection pump feeder line that went to the OEM filter housing and turn it into a fitting I could attach to the fuel hose, then add a return system.

Getting to the injection pump inlet fitting was, how should we say, unpleasant. Again, no overhead view, so this was done with a phone camera inspection video and then by feel. First, I had to remove the intake plenum thing to get access to the injection pump’s backside, which was an easy enough operation (though I had to loose and shift, but not remove, the turbo). There’s only space to turn the wrench 1 hexagon side at a time.

And here it is, the original filter to injection pump line.

I used a tube flaring tool from Harbor Freight to cut, then form, then put a gentle flare onto the end of the rigid line. It’s supposed to stick up just a little out of the center valley so I can slide the rubber fuel hose over it.

If taking the fitting off was a lengthy video game side quest, then re-mounting it was some kind of next level miniboss that didn’t even drop goodies. I had to do most of the initial mating and threading by hand.

The updated feeder line terminates in this photo just under the rubber vacuum hose to the right.

Here’s a new front-towards-back view of the now much more spacious engine cave.

The original fuel feeder line coming from the selector valve was wrapped around under the front of the engine, rising upwards on its forward passenger side face. I gently bent the rigid line where it began on the frame to point towards the back of the engine. Again, slightly badly lit photo, but you can see the “Nipple to Nowhere” pointing downwards in the center, which is where I’ll attach the new fuel line.

While doing this, even more parts had been arriving. A new expandable intake hose, for one, but more importantly, I received the electric solenoid valve and fittings for making a device I nicknamed the Dongle of Diesel Distribution:

So here’s what’s going on. The DDD takes in fuel from the pump/filter on the bottom left fitting. The electric solenoid is connected vertically above it, in order to give a high point for air to collect. It then does a U-turn while touching a pressure sensor, and the injector pump hooks in on the rightmost fitting. The top “exhaust” fitting will be routed into the fuel return lines.

I decided it’ll mount right here, at the studs where the former OEM filter housing was located.

I decided to get silly and design up a snail-shaped mount to be 3D printed. Bent piece of sheet metal? Sure, why not. But that wasn’t extra.

Whatever, it’s a snail if you squint hard enough.

It’ll be made on one of my Markforged machines from their carbon fiber nylon composite material, Onyx. My favorite vegetable for making dishes as diverse as entire beetleweights to welding fixtures to …. stuff like this.

I actually modeled this up and had it running on the printer while I was doing the plumbing work that night, so it was ready by the morning!

The finished snail bracket assembly! The only place to “mount” this so to speak was using the solenoid valve’s mounting holes.

I grab one of the studs of the former OEM filter mount to locate this thing, and also function as a ground point for the solenoid valve.

Am I confident that the print will survive underhood temperatures? Absolutely. Hell, just about everything in a new car is made of fiber-filled Nylon of some sort… to my chagrin.

Time to do some final plumbing. I’ve linked up the injection pump (hose labeled -> IP ->) and the feeder line, and the free hanging one will be the return vent line.

For fuel pump power, I fished up a long 16 gauge wire following existing brake lines to meet the repurposed fuel heater power drop.

Here’s what’s going on underneath. The orange and black bundle going off to the right is the fuel pump power.

The DDD purge solenoid is grounded on the OEM filter mount stud and I ran a purple wire up and over the engine cave (note the orange and purple wires in the wiring tray at the top) to meet the solenoid wire.

I connected the solenoid wire to a 12V access point at the Centurion-supplied fuse block. Then I pulled the doubled-up wire into the cabin via the same terrible, un-insulated, un-grommeted hole everyone else has been using (“Not the better redneck, just the most recent”) and the cut the doubled up loop. Now I just need to connect the ends to a switch to enable the solenoid.

A photo of the Wiring Teratoma now with my own additions (blue overdrive connection, purple purge solenoid….)

I found a button switch in one of my Collections and decided to just position it above the fuel selector switch. It’s a momentary button, so if I ever do some kind of service on the fuel system that empties it out, I’d just key ON (not start) and hold the button a few seconds to let the system quickly prime.

To be fair, once you have an e-pump, it will eventually shove all the air out of the system anyway, save for any air that might be trapped in the injection lines themselves which will need to be individually bled at the injector (no thanks) or cycled out through brute force.

On the reassembly path some more! Here’s the back side of the intake reassembled with the new extend-o-hose, now free to run diagonally across the engine cave without tripping on ANYTHING.

The “Cold” “Air” “Intake” is now back in place as well. That’s really all there is to it for this install.

And now we’re ready to fire back up. Verdict? Well, it works the way it’s supposed to. If I push the purge button, fuel begins blasting out of the return tee junction instead (oops, forgot to tighten that clamp). However, now that the system is being consistently pressurized to 10 PSI, I’m watching ALL of the injector return fittings spew diesel fuel every time the pump is running.

Welp. That’s what the next post in this series will cover: all the collateral damage, including repair of the return lines and fittings. While I waited on these parts, I also decided to get new glow plugs and repair that circuit.

The Summer of Ven: IDI Fuel System Teardown and Electric Fuel Pump Retro-mod

This series of posts will detail the first major system modification I perform to the IDI 6.9 liter engine of Spool Bus, inspired by the work of other enthusiasts like Nick Pisca.

After finishing the brake system work and getting it driving well, I noticed that it suffered from a pretty badly aerating fuel system. As I mentioned in the Murdervan post, the IDI engine family depends on a fuel system that is fully primed and free of air, or they tend to have severe starting issues. Coupled with a mechanical fuel pump that’s crankshaft driven, and it means a lot of work is dropped upon the starter (and therefore batteries and heavy power wiring) to turn over and keep cranking an all-original engine with dried or cracked rubber hoses to pressurize the system. Spool Bus definitely exhibited this problem along with a non-functional glow plug circuit, making things even worse.

To make up for it, I would do the unspeakable thing and feed it a tiny puff of ether (starting fluid) if cold starting. It would always getup and go immediately, which indicated to me there wasn’t really anything wrong besides the aerating fuel lines. With fall and winter on the horizon, I decided to go for the mod both as a quality of life improvement and because the system needed addressing anyway.

The changes entail removing much of the OEM fuel delivery system and replacing it with an electric low-pressure pump to feed the high-pressure injection pump unit, as well as relocation of the fuel filter mount from its basically-impossible-to-service OEM location under the engine cave ceiling.

See, a lot of these parts would be perfectly reasonable from a service perspective with overhead access in the pickup truck line. But when you shove all of it 2 feet backwards with the engine squarely under the dashboard, those OEM locations just make you go what. how. WHY. I keep saying Ford (and other manufacturers!) should have just committed and kept the van line cab-over, but I say that as a die-hard defender of the Church of the Cab-Over Van.

So here we go! Part 1 will focus on deconstructing the original fuel system, basically acting as a pictorial guide if you might ever want to fix one. Next will be the installation of the new electric fuel pump, and then I’ll clean and wrap up everything with new glow plugs and return lines.

Up in the “Service Position” it goes! I promise, this is far less sketch than it looks, as for some reason the slope of the driveway is exaggerated by the framing of the picture. That’s also what wheel chocks are for. The previous renter of this place left these big cut up railroad ties that worked suspiciously well as ramps, so maybe we had the same idea!

We’ll start with the underbody inspection. So, Spool Bus has no less than three fuel filters. I think people just added more fuel filters as they got clogged or something, not gathering that’s not how it works. I’d been getting some fuel feed problems before this where it feels like it’s running out or pulling air, losing some power while cruising. Having experienced this in Mikuvan back in the old’ dirty gas disaster days, I figured this was another impetus to finally making the mods, which is basically another chance to dig through what previous owners had done. The state of service of a van always tells a story, often a tragedy.

The item shown above and to the right of the yellow (new!) from shock absorber is the OEM fuel-water separator fitment. I figured it was OEM, as it was located in a spot that only Ford could have installed BEFORE they put the van part of the van on the van.

Next, moving just a few feet back, on the frame was another fuel-water separator unit. This is plumbed in right before the fuel tank selection valve, just inboard of the frame rail from it.

….and I know it’s hard to see exactly what I mean, but the white object immediately behind the A/C compressor shown at the bottom is the OEM fuel filter and its mounting fitting. Yes, far as I can tell, to remove this thing and replace it you have to actually unbolt the A/C compressor.

I always felt like the van line of any car company got the most disposability treatment. I mean, why not? They’re generally the most vocational of the product line. Buy them for your contractor, plumbing, environmental disaster response, etc. fleet, run them for 50,000-70,000 miles, and then throw them away before anything becomes a problem.

So the OEM water separator has a little cable coming out of it that leads to this knob under the driver’s seat. You pull it to pull up on a plunger inside, and theoretically with water being heavier than oil, all the water collected at the bottom will drain out. Pull the plunger too long and you drain out your fuel system as well ¯\_(ツ)_/¯

I decided to dismount and mess with all the filters to see if they were exceptionally clogged or something to cause the fuel feed issue. I mean, the answer was Probably Yes, but I wanted to be thorough and see it firsthand anyway.

I yanked off the frame-mounted filter and… eww. It was chunky inside from an uncertain source of brown. I read that algae and other simple life forms can begin growing in situations where oil and water sit together too long. Whatever, I don’t care. Obviously, we needed a replacement here.

With a bit of hose following, I found out that the OEM water separator was actually no longer in the picture. I might uninstall it one of these days, but not right now.

To uninstall the OEM filter, I had to remove the intake hose and luckily was able to sneak a strap wrench in there just enough to start breaking it loose. There was just barely enough vertical volume to wiggle it out afterwards!

So here we have the two “Original-to-me” filters. I decided that the existing frame-mounted filter head was fine and dandy for anything I wanted to do – no use to purchase a new one, even if it’ll be fancy. I’d mount the electric fuel pump right next to it on the frame, and just run a hose straight from there to the engine.

There does need to be an air purge method located at the highest point of the fuel system. For that I brewed up a plan to use an electric solenoid valve connecting that point to the fuel return system, and so I can activate the P U R G E from inside if need be, instead of having a manual fitting like the Schrader valve on the OEM filter head.

Time to start deconstructing from the back side in order to remove the rest of the fuel system. Remember, this bullshit is what I’m dealing with. There is a LOT going on inside the engine cave of the Ford van chassis, even without Dashboard Turbo giving me the side-eye here like he owns the place. Nick’s assertion that the most valuable real estate on a van is under the hood and inside the engine cave is absolutely correct – whatever I can remove from here is added service access and airflow.

First to go is this torn up plastic coated metal coil intake hose. So it’s just been pulling air from wherever the hell it felt like all this time, huh? I’ll order a proper new one when I get to that point.

This is the view from the driver’s side of the engine cave, out towards the front. On the left, the shiny cylinder is the rear of the A/C compressor. To the right of that is the OEM filter head location, and to the immediate right, the black casing is the turbo compressor’s outlet adapter to the intake.

That’s right, there is NO blow-off valve or intercooler here. Just straight in…. as well as straight out. There’s no wastegate attached to the turbo either. It’s just “sized right” and with a 1000 pound blob of cast iron underneath it.

The view going the other direction, peeking in just under the hood apron. At the end of this adventure, the metal tower that is the OEM filter mount will be gone.

I’ve got a bunch of other hoses removed now, and also have removed the crankcase pressure regulator (the can at the bottom), which I’m led to believe works like a very overgrown PCV valve. This was enough volume for me to get a read on where to route and mount everything.

Fast forward a few days, and a combination of Papa Bezos and RockAuto have #delivered. I also just took the old filter to an O’Reilly and held it up to them and went ? ? ?, picking up a combined filter and water separator (that little knob at the bottom loosens to drain and also cover you in diesel-water poop)

Also in the order is the electric pump itself. I went for the near universally recommended one, a Facet DuraLift unit, and also ordered a bunch of brass fittings to match.

I also picked up a “fuel pump block-off plate”, seen in the middle of the fuel hose coil. I obviously didn’t know this, but it seems like every mechanical fuel pump for decades was the same hole pattern in the side of the engine, so there’s like only 2 products that cover up the hole for every American vehicle ever.

Step one of this whole disaster: Remove the mechanical crankshaft-driven fuel pump. Apparently the diaphragms inside these pumps can eventually (or prematurely) fail, which then dumps fuel into the crankcase. Great!

This photo makes it look like a reasonable service position. It is in fact not. I’m looking upward from just inside of the front passenger side wheelwell. The structure at the left is the engine cradle/crossmember. The orange b u l g e is an aftermarket coolant filter some previous owner installed (hmm, this is a good idea in general) which was absent on Murdervan and made this whole adventure that much harder to navigate.

Of course you can’t see the bolts either. If you ever want to work on vans of any sort, you have to be really comfortable with “Braille Servicing” out of sight and only having your proprioception and tactile feedback to let you know if you landed the socket or started the thread.

Face Down, Ass Up, That’s the Way We Like to [adjust the power steering belt tension on a 1975-1991 Ford Econoline]

I got a start on it with removing the fuel feeder line coming from the switchover valve (rubber, bottom nipple) and unscrewing the rigid line going to the OEM filter head (flare nut, upper fitting). The bolts holding the pump on are standard 3/8″ with 9/16″ wide heads.

I went ahead and pulled up the rigid line from the front of the hood after undoing a few clamps holding it to the engine.

The rigid line has a heater element attached to it that’s powered from a fusible link system coming from the passenger-side (primary) battery. I have no particular use for this, but will be tapping the power for the fuel pump later.

To remove the fuel pump, I actually found it easy enough to use a standard box end wrench. I didn’t have a ratcheting-end box wrench or a socket that would actually fit in these confines, so I just suffered through it with the initial loosen, and then the removal by hand was easy enough.

And here it is dumped out the bottom. Installation of the block-off plate was far more pleasant, as there was now nothing in the way.

Next up is to remove the OEM filter head and its fittings, also easy enough with a 9/16″ ratcher, though the approach angle is better from the front-right position (shown here).

Here we have the pile of scrap generated from this evening’s operation. Well, I suppose the intake pipe adapter isn’t scrap, but it happened to be laying here as well. Some of these rigid tubes will be harvested for their fittings and make it back into the operation.

Next up, re-plumbing the engine fuel feed and adding the electric lift pump!