Wires, wires, everywhere

It's cabling not wiring

Rear battery pack cabling complete

Working with 2-0 cable

I finally finished running all the high voltage 2-0 cabling.  This included the jumpers on the battery packs, wiring from the battery packs to the motor controller, and wiring from the motor controller to the motor.  Working with 2-0 welding cable is a different kind of wiring than I'm used to.  You don't just snip this wire and screw it to a terminal.  Just cutting the wire, stripping it, and attaching a terminal is a significant task with special tools.  You also have to very carefully plan how you're going to run the cable.  This stuff doesn't bend like #12 house wiring.  The bends need to be gradual and you have to get the lengths just right.  It was especially tedious to run the two lines from the rear battery packs up to the front of the truck.  That task took a lot of creativity and 1/2 a day.  Most of the time was spent designing and fabricating the clamping points.  The cable needs to be secure without any points where it might rub on a sharp edge and wear through the insulation--that would be an unpleasant event.

Motor controller & DC-DC converter

Welcome to my hood
With the rear battery pack jumpers done and the main lines run to the front I tackled the under-the-hood wiring.  I wanted a breaker on the main line so it was easy to disconnect the power to work on the components.  This turned out to be a non-trivial exercise, again due to the difficulty of working with 2-0 cabling.  I was able to fabricate a bracket to hold the breaker out of 16 gauge sheet metal.  I found a nice plastic box to enclose the breaker at my local surplus store.  Not sure of it's original purpose, but it makes a decent electrical box. Again I had to make a bunch of short 2-0 cable jumpers to complete all the high voltage wiring under the hood.

With the high voltage cabling done, I moved on to running all the low voltage (12v) control wiring.  This was much easier, but still tedious.

Oh what a tangled web we weave

Legacy 12v wiring harness

I now have two major wiring tasks left.  The first is to hook the DC-DC converter up to the legacy 12 volt system for the truck.  The 12 volt system is powered off of the main (116 v) battery pack through the DC-DC converter.  This is not a simple as it sounds.  I'll need only about 20 percent of the old wiring system--just that portion that runs the lights, and accessories. All the wiring for the engine, ignition, alternator, and engine control module can be eliminated.  The difficulty is figuring what wires to get rid of and what to keep.  I've got all the wiring diagrams for the truck, but this is another tedious task.

The last wiring task is to hook up the battery management system (BMS).  This requires installing small circuit board on each battery cell and then wiring them into the BMS.  The circuit boards on the cells measure the voltage of each individual cell and can shunt the charge voltage around the cell once it's fully charger.  The BMS keeps track of the state of charge of every cell and controls the operation of the battery charger.

We'll I'm now going on 6 weeks behind schedule.  I'm thinking I might make a Thanksgiving completion date.

HVAC Detour

Beware of Simple Tasks 

The now dashless truck interior

A few weekends ago, my friend Chris was over helping with the conversion project and I said, "why don't you take out the old heater core so we can put the electric heater in."  I was thinking this would be a nice couple hour job he could work on while I worked out some wiring issues.  Well it turned out getting to the heater core required removing the entire dashboard--simple enough right?  Wrong!  Four or five hours later we finally had the dash out.  As with nearly every detour, there is a bright side to this one.  With the entire dash removed, I have easy access to all the heating ducts and was able to remove and thoroughly clean them all.  This turned out to be pretty important.  The previous owner use the truck for a landscaping & maintenance business and I've found dirt, grass clippings, and mulch debris in every crevice of the vehicle--inside and out.  I now have clean, dust-free ducts.  It's also a lot easier to clean all the crevices and niches of the dash board when it's not in the vehicle.

Electric heater core in place

The electric heater core is substantially smaller than the old liquid heater core so I had to make an adapter to get it fit into the duct properly.  This gave me a chance to learn a little sheet metal fabrication.  Fortunately I have access to a sheet metal shop and was able to use the brakes, shears, and punches to fabricate a sheet metal box to hold the electric core and fit snugly into the duct work.  It's a bonus that this whole thing fits inside a duct where it will never be seen.  It all works fine, but my first attempt at sheet metal work leaves a lot to be desire on the aesthetic side.

Old leaky master cylinder

The last little detour had to do with the breaks.  When I bought the truck there was a half-full bottle of brake fluid behind the driver's seat and the reservoir was about down to the low limit.  I soon had to add fluid to the reservoir, I figured I had some leaky cylinders at one or more wheels.  However the puddle of brake fluid under the left side of the engine compartment clearly pointed to the master cylinder.  I wasn't really looking forward to rebuilding the master cylinder and was please to find out that I could by a refurbished master cylinder at a reasonable price.  All I had to do was unbolt the older cylinder move the reservoir from the old cylinder to the new one, and bolt the new one in place.  Actually, bleeding the new master cylinder on the bench took longer than replacing it.

I've now finished most of the major mechanical stuff and am moving seriously into the electrical part of the construction.  Things have slowed down quite a bit now that summer is over.  I'm into tortoise mode-slow and steady.