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Full time dilettante

“It’ll take a few days, a week, at the most.”

This is what I told my wife, in order to convince her that I was qualified to rewire my vintage truck, I gave her a gross exaggeration of the time frame. Fortunately, I had simplicity on my side, an International Scout, is about as basic as it gets. I’ll allow the following Google searches tell you how qualified I was for such an endeavor:

“How to crimp a wire.”

“How to solder.”

“How to make electrical connections.”

Which might lead you to ask yourself, “Why the heck is he doing this anyways?”

A local shop quoted me $2,000 to rewire my Scout. I could buy a harness for $200, so I figured it was just a time consuming process, and fortunately for me, I had a lot of time on my side. After flicking though endless pages of online forums, I narrowed down what I needed, and what I should avoid.

The candidate, a 1970 IH Scout 800A, belonged to my dad before it fell into my care. My dad took the time and money to make it into a surprisingly civil and pleasant vehicle to drive, for a forty five year old street legal tractor. That’s only if you don’t need heat, air conditioning, radio, or a fuel gauge. The unsynchronized transmission demanded patience and skill to shift.

I inherited this vehicle, blind to my dads true intent—sick of pouring money into an old truck, or perhaps just running out of garage space. I was in love with the truck at a young age, long before I could drive, as I’d sit in the passenger seat and bounce down dirt roads. I learned to drive stick in it, and the old truck seemed to embody everything I loved about cars, that would never return in the current trend of modern trucks. I loved the utilitarian nature, the practicality, and the over all robust reliability, which could take years of neglect, and still be fixed with a set of tools most of us have in our garage.

The Scout, like many old trucks, is host to numerous mechanical and electrical quirks that are too long to list. Instead of trying to fix the turn signals, stop lights, fuel tank sender and the multitude of other electrical connections that rely on a 47 year old wiring harness, I decided to start from scratch, and replace the whole thing.

My mechanical aptitude, or lack there-of, finds support in my persistence. If I take on a project, I will do anything in my power to make sure it’s complete, or that I at least didn’t go down without a fight. Many of these projects arise out of wanting to save money, or wanting to learn a new skill. So you can guess how I arrived on the genius idea of rewiring my 1970 Scout in the middle of a Michigan winter in an unheated garage.




The harness arrived in a massive tangle of multi-colored wires and plastic connections. I quickly explained to my wife that I might be in over my head, she rolled her eyes, a common and fair assessment she frequently used during this project.

I began by photocopying the wiring diagram of the Scout and blowing it up to poster size. I pinned it on my wall and traced the wires with a tip of a pen through the diagram, like a treasure map. 

My next step was to wrap my head around the theory of electricity, why it goes the way it does, and what it needs to get there, or what it might need to stop half way or be turned on and off.

The entirety of this project, my resources, and information was provided entirely for free by generous people much wiser and more patient then I, via the Internet.  I scoured web forums, Googled endlessly, and read too many article to count.  With the right amount of patience, it seemed I could rebuild the entire truck by browsing 4x4 truck forums. Slowly, I was beginning to figure this out, and it was all thanks to strangers.

My next step was one that I had been anxiously waiting for. I had to remove the old harness, and while most people suggested going about this willy-nilly, I deemed it wise to try and keep things intact for a reference later on down the road.

With side cutters in hand, I proceeded to nip, and clip my way though the wiring harness. What I discovered was the reassuring fact that, the harness was in a pathetic state of disrepair, and mice just loved my dashboard. My other concern was IH’s affinity for the wire color green, and how they used that color for 99% of the harness. The wires had small black numbers printed on them, but expecting those numbers to stay adhered after 45 years of neglect is being unrealistic. As my clipping and nipping continued, I was amazed at just how well the Scout ran with the current state of the wiring harness. Wires were frayed, connections corroded, and bore the visible scars of previous owners attempts make “repairs.”

To see that pile of gritty and frayed wires next to Scout was very satisfying. This feeling was quickly overcome by fear, the inevitable feeling when one reaches the point of no return. The Scout was going to sit where he currently was, until I either hired a truck to tow him away, or I finished the project.

I began at the rear, tracing the path of the older wires on the frame through a labyrinth of car parts.

Before I began this project, I made a commitment to make a neat and tidy job of my work. If I was going into this project with such little expertise, there was one thing I could do well, route wires neatly, keep everything organized, and tidy. I insisted on weatherproof connections everywhere, no matter where they were, and heat shrinking those that were exposed to the elements. Should this project fail, as I watch a tow truck whisk my Scout away to a garage to finish the job, at least I’d know, they’d be impressed by my meticulous detail and organization, even if I had everything wired backwards.

What followed was a short-lived—but savory—feelings of accomplishment as I got the taillights, stop lights, and backup lights wired up. The dashboard came next, where these feelings vanished in the tangle of circuits, gauges, switch’s and doo-hickeys.

I went back to the Internet to seek what an ammeter was and why it was different then a voltmeter. I found the answer, backed by various opinions on why I should throw it out and replace it with voltmeter. One goal of this project was to not just replace the harness, but replace any outdated technology that could be swapped with more reliable parts.

The voltmeter replaced the ammeter. Which would lead me to my next hold up, the regulator. My scout had an external regulator, something the instructions that came with my harness gave no instructions for. To be fair, the instructions didn’t give me much in the way of guidance, or clarity, and I’m not sure why they were even included in the box.

I would later learn, that this style of regulator is outdated, if I wanted to, I could continue to use it, or buy an alternator with an internal regulator. This would simplify the harness, require fewer connections, and clean up the engine bay. Out went the regulator, and the alternator, replaced by a modern unit. I was making progress, slowly, but it was progress. This was about four weeks into a project I deemed would take a few days.

Progressed continued—tools were thrown, spirits crushed, expletives shouted at non-sentient objects. Hobbled and contoured in strange positions underneath, on top, and under each and every side of the Scout, the process was becoming a test of physical and mental endurance; pointing the heat gun at my fingers to revive circulation, whispering to myself in the blue haze of the fluorescent lights, red wire, or was it green, was that sixteen gauge or twenty, left or right headlight….

The most time consuming part of this project for an expert is terminating the connections. But when you make a connection, realize it’s the wrong one, and you’ve routed the wire in the wrong place, your time spent on each connection increases astronomically. Top this with my juvenile dexterity, and increasing self-doubt, the project hit roadblocks.

I Googled grounds, and found out why they mattered and how important they were. I replaced mine, adding three new ground straps, proudly grinding the contact surface to a silver shine.

After six weeks, forty-two days, of wrenching, routing, crimping and heating—the harness was in place. Whether or not everything worked was a whole different matter. I checked for a parasitic draw, and sure enough, there was one. Several days of sleuthing, prying and begging, I found the light switch I installed incorrectly.

The next day, I sat in  the drivers seat, my left hand nervously slipped the key into the ignition. What followed was the culmination of the past six weeks, freezing my ass off in a garage, in a ten second sequence. I pulled the choke, pushed the gas pedal down three times, and cranked the ignition.

The engine turned over, enough of a reaction to send my spirits to the moon. Unfortunately, that’s all it did. Turn over. Before the project, Scout was a turn-key truck, it always started. Replacing the harness shouldn’t change any of this, or so I thought. The most frustrating part, was that it was on the cusp of roaring to life. The V8 fired on all 8 until it was just on the fringe of exploding to life, rewarding me for all my hard work in thick curls of blue and black smoke from the exhaust, but it wouldn’t budge.

I went back though the connections that feed the ignition and the starter. By now, I was beginning to fell confident around the harness, or at least I could call everything by its proper name or function. I pulled the ignition switch, checked fuses, checked fuel, spark, and the battery. I even went as far as looking for a mechanic who could make a house call, is that a thing?

At the end of the day, weary and frustrated, I flicked the light in the garage and went inside. The next morning, I checked the distributor, I vaguely remember pulling of the coil wire that feeds the distributor, and perhaps I didn’t plug it back in properly.

Scout roared to life. I just sat and smiled; listening to the deep growl of his idle echo in the garage. My wife gave me a hug.

I now have turn signals, stop lights, and a whole host of creature (and legal) comforts. If you told me what I would have to go through to get there before I started this project, I wouldn’t of believed you, but I wouldn’t of gone any other route. I now know Scout inside and out, why he works, and how to trouble shoot.