So there I was one fine (a.k.a last) summer collecting some parts for the MOST RECENT PROJECT CATCH (never before seen on this site! Yet!) with Spool Bus, having been recently been re-HVAC’d such that I no longer had to risk dehydration simply puttering it over to the shop or a car meet. The application called for the same model E4OD transmission that I retrofitted into Vantruck as part of IDIocracy whereas Spool Bus and pre-op Vantruck used the older C6 3-speeder with overdrive pods.

For the van chassis, the transmission had to be a narrow year range for drop-in compatibility – 1987 to 1991, during which both the F-series and E-series used shifter linkage rods. Transmissions made after 1991 switched to a shifter Bowden cable and began relying on electronic speed sensors instead of the mechanical speedometer gear. On top of that it had to be for the diesel bolt pattern, because Ford handily lost the bellhousing wars to GM. The transmission would need to be dismantled to change that shifter input, so I wasn’t really keen on making an off-year work.

I stalked a whole bunch of regional yards and found a candidate around 60 miles away. After explaining once again, to another junkyard, that no I wasn’t here to sell the vehicle to the yard, I embarked on my merry way with a new-to-me 1991 E4OD transmission from a dismantled diesel box van. (They were so enamored with the project that I also got the shifter links and doodads for free!)

Now, to get home day to day, I usually pass by one or two water treatment facilities located close to the river where the highways cross. For some reason that day, the area smelled extra spicy and chemically as I approached. Fine, I thought. Maybe they’re doing some kind of pool bombing operation or deep cleaning the poop mash tuns.

Except then the spicy chemical smell began visibly collecting inside the cabin. Remember, Spool Bus had working HVAC (ok, just H-V and no A/C) again, so it was pulling the stank from somewhere. It was then that I realized the chemical smell was that of burning plastic and PVC wire insulation, not something typically pumped en-masse into the poop fractionation towers. I wonder what’s on fire this time, said I, having become numb to having vans catch on fire for some reason.

My mistake was hitting the brakes to pull over and inspect, which caused a massive smoke cloud to suddenly puff out from the hood vents and into the cabin. This means whatever was on fire was being fed by brake fluid being pumped onto it like a really cursed oil heater burner box.

If we’re keeping score, at this point I’m going 70 mph on an interstate, while potentially on fire, without a way to stop and do something about it.

So what did I do in this absolute situation? Drove the bitch straight home, what else.

I didn’t bother stopping (well, not like I had a substantial choice in the matter) and after being confident that the electrical fire was no longer an issue, manually dropped into 2nd gear and then simply crawled home slowly (Woe is me, for I am old truck, beset by mechanical problems! Hark, my hazard blinkers!) using the parking brake pedal with the unlock handle pulled out to modulate final stops at red lights. I count my blessings that a Ballistic Nissan Altima did not suddenly dot product itself with me.

I am also keenly aware that none of this would have been possible in a new app-car with an electronic parking brake caliper and fully electronic transmission. Honestly, part of my love for old decrepit mechanical things is the ability to force many fallbacks and partial solutions instead of being locked behind software-defined hard fails.

Well, now that I made it home and am clearly not writing an article for The Autopian about how Spool Bus burnt down on the side of the highway, it was time to do some battle damage assessment.

It was immediately apparent once I pooped the lid as to what happened. On a lot of older trucks with retrofitted trailer brakes, there is a third brake line that is tapped from one of the master cylinder ports, typically the rear circuit. This extra hydraulic line is routed inside the cabin to a trailer brake rheostat that is actuated by the pedal movement, and that is how power gets passed to the electric trailer brakes.

So people just tend to route these lines wherever and Spool Bus came with a particular lazy routing where it just went up and over the master cylinder and punched through the firewall somewhere on the driver’s side corner. What basically happened is at some point, the battery cable that very rudely touched the master cylinder fell out of the old broken plastic cable tray above it, and on my trip home, finally wore through its cracked 40 year old insulation and grounded out through this trailer brake line.

In doing so, it probably heated up and sagged, also cutting through the spring strap holding the master cylinder lid closed.

Check out these ends of the trailer brake line and lid strap! They look like they’d been used as stick welding electrodes which….. isn’t far from the truth.

The probably red-hot trailer brake line melted through a bunch of things. The plastic vacuum reservoir serving the power brake and HVAC selector system (as diesel engines do not natively produce manifold vacuum, a vacuum pump hitched to the engine pulls these little bubbles down for the brake booster to use), basically all of my appended wiring to bring back the overdrive unit and air purge solenoid valve, and a fair bit of the main engine wiring harness.

This hole was where the whole thing grounded out. Spool Bus just has a bunch of these random holes drilled into the firewall with random stuff pulled through it, including wires (including some of my wires too so I’m not entirely morally clean, to be fair).

So, in short, Spool Bus was a time bomb on multiple fronts. The battery cable had probably been resting on the trailer brake line for a while, and if that didn’t eat itself, any one of the other wires could have grounded out on the sheet metal and melted. At this point, enough was broken that I basically had to redo a lot of the wires from scratch and replace all the vacuum canisters anyway, so it was time to just commit to taking it offline and doing everything properly.

Like look at this battery tee clamp. That’s 30+ years of being bent and pried and hammered back into the right shape, and it was so wallowed out it needed a spacer sleeve. All of this I’d be replacing with new wire and new connectors.

Doing the teardown also uncovered other funny things, such as the fact that this auxiliary vacuum canister had rusted out probably some time into the Clinton administrations. Spool Bus always had a very mediocre brake vacuum assist strength, The fact that one of the vacuum cans is just not (a failure to suck, if you may) could explain a lot.

The diesel chassis came with these extra brake vacuum reservoirs They looked very much like repurposed coffee cans with a fitting attached. No treatment of the metal meant the thing basically crumbled in my hands, and almost every one I’ve encountered in the wild has been the same condition.

As a random aside, I found out while unbolting the battery cable from the starter motor that one of the bolts holding the solenoid on had fallen out and the other was loose and handing on by 3 threads. Again, something something time bomb how was it even running.

The closest screws I could find that fit were some random ones from a bed frame I took apart. Quality repair!

So, to start with, here are the three large wires I had to reproduce. Two battery grounds and the large parallel wire that goes between the two batteries and to the starter motor and glow plug contactor.

Not a very difficult challenge with my stash of leftover 2/0 size wire, both spare stock from IDIocracy and stuff I harvested elsewhere. I just had to pick up a few crimp-on clamps and ring terminals.

Here’s a view of the new tee junction that goes on the primary battery. It serves the glow plug circuit as well, and has a tap for general vehicle 12V power.

Replacement cables prepared and ready! This was the easy part, honestly. Everything else had to happen before I could install these battery cables. Specifically, I had to replace the master cylinder, run a new trailer brake line into the cabin, and then repair all of the melted accessory wiring. Oh, and replace the vacuum bubble and line that melted too.

I was never a fan of this kind of old school cast iron master cylinder. I’ve only know them to leak from the lids because the metal rusts and no longer provides a good seal. It turns out they make exact replicas but in aluminum, so that will at least alleviate the rust problem.

Here’s the wound that the blazing brake line cut into the vacuum reservoir!

I cut back and re-flared the service brake lines because the new master cylinder had different threads in the ports and needed new flare nuts anyway. Not only that, I discovered the fittings had a fair bit of corrosion at the flares too, something you definitely do not want to see.

The new aluminum-bodied master cylinder fully installed. The little block on the right is the tee junction where the trailer brake line comes out.

I decided to do something about those infinite “Rust Hole or Drilled Hole?” firewall holes. These are a few different TPU 3D-printed bushings. I cleaned up most of the holes to one of two diameters, 1/2″ or 3/8″, and made press-in bushings to fit.

Here’s what they look like! Now I can have my pick of any number of different Rust-Or-Drilled holes to route the replacement accessory wiring through.

Also, you did NOT see this. There is no massive gaping rust hole entirely through the inner cabin wall and fender apron wall. It definitely does not pour water through here if I drive in the rain. What an absurd concept.

I’m routing the replacement battery cable and OEM engine harness through a large wire loom which will be retained to the upper firewall flange with some straps. This is the same approach I took for Operation IDIocracy in Vantruck. The OEM wiring tray that crosses this area is, by now, always completely deformed, heat-damaged, and otherwise deteriorating.

What the driver’s side looks like now with replaced battery cables and hangers.

I cut back and re-spliced the two addenda that I put in – the overdrive shifter solenoid and the fuel system air purging solenoid. The new wires live inside looms, and pass through the now protected Random Rust-Or-Drilled holes!

I also cleaned up how the starter wiring climbs up the side of the engine bay, as long as I had everything taken apart.

The last operation was to create a trailer brake line that went into the cabin roughly where I needed it. This was done largely using eyeballing a small ruler I held at various orientations to get an idea of where it was going, plus or minus a bit of slop length.

The new trailer brake line runs under the master cylinder and then under the auxiliary battery tray. It should no longer be directly carrying battery current.

It also tees in coming from the bottom, so the whole system will “self fill” if I just keep the master cylinder topped off. I wasn’t sure how you were ever supposed to properly bleed these mechanical trailer brake controllers, because they didn’t have bleed ports. Even if you just left the fitting in them loose and squeezed fluid out with the pedal, the way they’re oriented there would still be an air bubble at the very end! I guess it just didn’t matter enough. The answer to many of my Car Questions about “How did people back then do X” has been “well they just didn’t”

Final closeout time! I fixed the hanging reflective tape, don’t worry.

As I wrapped up the repair on a Friday night, my first inkling was to go get some food to road test it all. I stopped by the local gamer bar (which, sadly, has since closed because the area it’s in is one of those overpriced developer hell projects). I’m proud to say Spool Bus can stop once more, and doesn’t try to MIG weld using brake lines either. Also, in checking over everything on the fuel line side, it turns out the front tank aerating was caused by a giant crack in an old fuel hose I didn’t replace the first time.

Really the only small-but-irritating problem staring at me each time is that the oil pressure gauge itself is broken, or the sensor wiring is broken somewhere inside the dashboard. Spool Bus might still have a ton of stuff wrong with it, but I think by the end of the summer it was at least in the upper 20th percentile of all trucks found in the South: Runs, drives, turns, stops, has lights, has wipers, isn’t profusely leaking one or more fluids, and you can even listen to crazy AM radio hosts. What else do you need really?!

Haven’t heard that name in a while, right? It seems like after renovating the fuel system way back in 2021, Spool Bus just kind of vanished off this website, except for appearing as background set in photos occasionally. That is because Spool Bus became sort of an unsung hero of the Old and New Robot Trap House: it was principally in charge of all the 𝕿𝖗𝖚𝖈𝕶 𝕾𝖙𝖚𝖋𝖋:

After all, can’t have my white elephant doing any work or something. Once the summer’s worth of mechanical work was completed, Spool Bus was simply a well-running and driving truck, albeit one with many peripheral functions missing or worn out. But that means I didn’t feel bad chucking scrap metal (above) or rocks and concrete waste (below) into it.

It is kinda nice to have something you don’t really feel bad subjecting to this kind of “throw it in and send it” treatment. Like, there wasn’t really anything I could do to Spool Bus to make it consummately worse than it already was, with gaping floor rust holes, almost every dashboard instrument dead, and a bed made of 3/16″ thick plate steel. And with that mechanical service front-loaded in 2020 and 2021, my usage cases were really so light-duty for the platform that I barely even touched it for all sorts of maintenance since.

This isn’t to say Spool Bus was only pulled out once in a prime number collision for some menial task. It not only participated in meme recoveries including, in this very year, the most arduous van recovery mission I’ve ever taken on (More on that story later), but I also regularly brought it around to local car shows… or just took it to the Tail of the Dragon for fun while chasing the Lemons Rally.

But gradually, the grievances did pile up. When I said “nothing in the dashboard worked”, I meant it. It had no turn signal pilot lights (though the blinkers and lights themselves worked), and the oil pressure and thermostat gauges were inoperable.

The wipers only ran very slowly if I hit a pothole in the correct way, a sign of the motor being just totally spent.

The HVAC blend selector was stuck on heat with the lever broken, so I had the choice (when the blower motor was actually working, needing a different pothole impact angle to work) of Hot or Even Hotter.

The vacuum system was so weak that said HVAC system could rarely get out of defrost mode, and I only had one pump of power brake assist available. This probably meant the brake booster canister was bad as well.

The front fuel tank’s feed line probably had a crack in the hose, because it pulled air instead of fuel and would aerate the fuel system nearly instantly if I switched to the front tank. So I really only had the rear tank available (whose gauge only reads below 1/4th, else it reads zero).

Let’s just say it was just getting really bad and uncomfortable to operate on the regular. So, in May, before the weather started entering truly hot and steamy territory, I decided to embark on the LONG HOT SUMMER OF SPOOL BUS, a quest to eradicate as many of these problems as possible.

At minimum, I needed a working HVAC system and wipers. Even if the air conditioning is toast, the Econoline’s front vents are not wimpy and at least lets things be survivable (Mikuvan’s front blower motor is very weak with wear/age, making it pretty deathy to drive in summer besides being deathy to drive in general).

So, I focused on those problems first. I pulled a wiper motor from a junkyard van many moons ago because it was right in front of me, and the intent is to just change it out while keeping the old motor for a future rebuild, as chances are high it simply ran out of brushes.

To do the HVAC selector/blend door system, I had to do a deep dive and take apart the entire thing from both ends, in order to reach and inspect the broken Bowden cable that connected them. So back to the scene I’ve been presented with many times…

Like I said before, I had no beef at all with how Spool Bus drove. Arguably it starts and runs better than Vantruck does (I have long suspected that this is not its original engine, and it had a proper rebuild or reman engine dropped not too long before it went in-op), and the little Banks turbo adds like 7 butt-horsepower and convincing sound effects. But this is definitely the layout that made me try out the low-mounted twins of Snekvan, then Vantruck, through Operation IDIocracy.

Knocking the dashboard down was easy enough, although the (sporadically working) radio is annoying because all the knobs have to be removed first to unscrew its faceplate. The HVAC selector pod is below the radio, so removing it is required.

On the passenger side, removing the blower motor and its cover is just a few screws. This allowed me to peek into the absolutely filthy poop-encrusted blower box and heater core housing.

That foam covered door is what moves when the temperature lever is pulled, and I think at some point it might have become stuck and then the cable broke internally. That, or the mounts cracked off. Either way, it was free to move at this point already.

The blower motor and fan wheel dismantled well for being rusty and 40+ years old. As I suspected, the motor simply became brushless over time. I had a replacement I bought a while ago, so this pile of motor got put in a Giant McMaster-Carr Bag for future rework.

I mean, all it really needs is brushes and maybe some oiling of the bearings. They’re just too simple to truly die.

To get to the Bowden cable that moved the flap, I had to remove the blower housing, which fortunately was just a couple more screws but required very close-quaters van combat above where the dashboard pad covers everything. Nothing but a few plastic-threading screws here though. The Dremel was needed to cut new drive slots into several internal panel screws which were thoroughly rusted.

(This was also a great chance to vacuum, air blast, and somewhat pressure-wash this whole box out because who knows how many animals have pooped in it over the years)

Interestingly enough, the Bowden cable was still fixed and working on the blower box end… but on the selector side, the Z-bend that used to connect it to the lever was snapped off. So, it might just have been fatigue over time.

The problem was that the small plastic snap that anchored the cable housing (so it could do the Bowden push-pull thingie) was also cracked apart. This meant the cable housing couldn’t stay in place any more.

Nothing a large, healthy blob of Sugru couldn’t remedy. At the same time, I noticed that the selector valve itself was slowly cracking open at the seam between the black and pink housings.

This probably helped explain why it would barely switch over, as it would just be a massive vacuum leak. I solved this by cracking it open the rest of the way, then putting a big ring of CA glue around the former factory joint and clamping it together.

My solution to the broken Z-bend problem required a big of digging into some very old parts bins…

I was just going to use a model airplane pushrod connector. In doing this, I sacrifice about 3/8″ of travel off the lever, so “Mostly Hot” is fully hot, but this worked perfectly on the cold (a.k.a Still Mostly Hot) side.

Getting the Bowden cable housing screwed in again on the other side, though, was one of those “double blind” van wrenching operations.

The first blind is visual because you can’t actually see what you’re doing because you have to face the other direction for your arms to bend the correct way. The second blind is tactile because you have to feel for where the screw hole is while simultaneously making sure the little plastic tabs line up, and all of this operation is occurring near where your fingers’ Jacobian matrix is as singular as you are.

But luckily, after enough wiggling, the Bowden cable was anchored on both sides again, and I regained control as to whether Spool Bus blew Warm or Warmer air into my face. As I said, the lever stops about 3/4 of the way up the Hot mark, but that is nothing a strip of black Gorilla tape can’t fix by visually blocking the rest of the way!

Alrighty, next task. It’s windshield wiper time! To remove the motor, I had to dismantle the windshield cowling which necessitated some Advanced Fastener Extraction techniques in some areas because the 40 year old Phillips head self-tapping metal screws had basically become smooth-head rivets from corrosion.

After the cowling comes off, most of the wiper mechanism is immediately accessible from the top.

The linkages and bushings were in surprisingly good shape without much slop. They’re held together by these funny little clip-on retaining rings, which were all on the borderline of disintegrating – if they do vanish, I’d just replace them with regular snap rings or E-clips. I took both of the linkages apart and cleaned and regreased them anyway.

The motor itself is removed from the inside underneath the dashboard. As you can see, there’s a pretty clear (for a van) path to getting its mounting scr….

No, just kidding. This is what the view ACTUALLY looks like when you start.

The shop books suspiciously skip over the fact that you have to dismantle out the fuse block, its little mounting bracket, the ground fanout bracket (on the upper right), and disconnect the brake light switch and cruise control vacuum switch. And, on top, the left side dashboard panel has to be removed and the ventilation duct behind it as well, which means you’re disconnecting the headlight combo switch and wiper switch too. All it says is “Remove Motor”.

Y’know, I’m starting to think I thought this was an easy job because the junkyard van already had all of those things stripped out by someone… so I was just looking at the wiper motor, going “Ah, yes, there’s nothing in the way!”

I took apart the junkyard motor for a quick visual once-over and to clean up and re-lubricate all of the gears and bushings (compare it at the top with Spool Bus’s motor with its totally dried out and crusty gearbox).

The parking switches on these things are just embedded variants of a self-stopping limit switch circuit, something I would do with a discrete snap-action or button switch or something.

The motor is able to receive 12V power through the normally-closed contact (shown in this position) via the springy copper strip until the little plastic finger pushing on it falls into a specifically placed divot on the drive gear. Once it’s in the divot, the strip gets pushed onto the normally-open contact (below the finger, with two little rivets).

At this point, the motor stops moving until the intermittent wiper controller clicks its relay, and that supplies a momentary pulse of power through this N/O contact, just long enough to get the motor moving and getting the finger out of the divot – at which point the motor runs as normal until it comes back around.

It’s definitely a very analog and old school way of doing limited-range motion without a modern encoder-equipped motor and its control module. Stuff like this still has a lot of appeal to me, because while it’s not very in-field configurable and changeable, it…. just works.

As with the blower, this motor has totally exhausted its brushes and only works if I smack it a few times, enough for the remaining stump to make contact (which is why I had to selectively hit potholes and curbs to get the wipers to cycle). So some time later I’ll pop it open and do that service and rebuild, including perhaps machining the commutator.

After SIGNIFICANT WIGGLING, I got the mounting screws lined up and piloted. These old rubber bushings are not very friendly when it comes to lining things up, and to make it worse, they’re in incomplete sockets (C shape, not a fully surrounding hole) so they like to fall out as I am trying to hold the motor with one pinky finger.

And the rest was simple. Now, when I said this self-parking motor circuit was “simple and just works”, I meant “Wow this motor just is doing whatever the hell it wants”. Some times, it takes 2 or 3 tries by the intermittent wiper controller for it to finally start doing the go-around thing. Other times, it parks and stops at this awkwardly high position. But after who knows how long, I could actually see in the rain again!

(As of September, this issue has largely resolved, and I think it was because the wiper motor contacts were probably old and not making good connections)

We’re not done yet, though. Not long after this round of work, one of the funniest van failure modes I’d ever experienced ended up requiring some Operation IDIocracy inspired shenanigans to recover from…