This section is defined as "Post Completion" changes and results.  All this means is that I drew a line and said the truck is "complete", and this section is what happens after that.  Of course it is not really complete!  I need updated instrumentation, a heater, possible changes to the power steering, etc.

This is also where I will talk about the performance and endurance of the truck.

   
Changes to the Vacuum Pump

As soon as I started driving the truck, it was obvious I had to do something about the noise of the vacuum pump!  It was very loud and it ran often and long.  It really detracted from the enjoyment of driving my creation.

In researching my options I ran across another S-10 conversion where the owner had replaced their pump for the same reasons.  They used an MES-DEA pump from Metric Mind Corp. and were very happy with both the speed of pumping and the lack of noise.  The specs looked good.  The noise spec for my Gast pump was <70 dBA.  The MES-DEA was <58 dBA.  Being a logarithmic unit of measurement, the sound power doubles for every 3 dBA, so this is a very large 16 to 1 difference in the sound power!

MES-DEA is a Swiss manufacturer, and makes these pumps specifically for EV's.  They make two models, one with about the same pumping capacity as my old one, and one that is almost double.  Even though the small pump would have fit in place of mine with no problem, I chose the larger one.

I had lots of vertical clearance with the old pump installation.  Careful measurements showed that the new pump would interfere with the electronics board, when it  was raised, by almost 1/4 inch.

I decided to lower the flat plate on my mounting bracket by about 1/2 inch.  I could do this as the new pump contains its own solid state pressure switch.  By removing the old mechanical switch from the top of the reservoir, I had room for the lowered plate.  I heated and bent the plate downward, then heated and bent it back level so the plate was dropped about 1/2 inch.  I then welded a strip of 1 1/2 wide bar stock to make the plate larger.  The new pump mounted on this reworked plate very well and clears everything.

The results of the change are worth every penny the new (and expensive) pump cost.  When I turn on the ignition in the quiet garage, I hear a hum, somewhat like the electric fuel pumps on modern ICE cars.  When I am in an area with ambient noise, I cannot hear it!  My initial pump-down time decreased from about 35 seconds to less than 20.  This is not quite a fair comparison as I now also am pumping down the original truck vacuum reservoir and the plumbing for the heating and air conditioning vents.  I never had these hooked up before, and it would take less time without them.
 

The new pump on the bottom is about 2 inches taller than the old pump on the top.  It has just about twice the pumping power, but is much quieter.

The old mounting bracket was flat.

The bracket I modified for the new pump had the plate bent down about 1/2 inch, and 1 1/2 inches of additional steel welded to the end.

The new pump fits in almost like it was designed to, and has adequate clearance all around.

I got my first clue to the actual cause of the problem  when I saw this melted insulating boot.

Things didn't get any better when I removed the boot and the cable.  The terminal is in pretty sad shape!

The fully repaired battery doesn't look bad at all!  The paint over the epoxy and roof sealant almost hides all the prior problems.  I think the color match I got by grabbing a Rustoleum can off the Walmart shelf is amazing!

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This is the clamp assembly. The black is the bed structure, the top being the floor of the bed with the front hat section below it. The violet is a doubler on the top surface of the hat section.  This assures a rigid member to clamp to. The hatched red is the swinging clamp.  The hatched yellow is a piece of nylon attached to the clamp bar, which is my version of a nylock insert.   It gives a positive drag to make sure the bar swings with the bolt once the clamp is loosened. The green is a plate that keeps the clamp from catching on the edge of the hat section and provides the positive stops. In operation, the clamp bar is aligned along the fore/aft axis of the truck, and the bed is lowered. The clamp clears the mounting bracket on the way down. The bolt is now tightened, swinging the bar under the mounting bracket (blue) on the frame. Continuing to tighten the bolt tightly clamps the bottom of the hat section to the mounting bracket, firmly securing the front of the bed down to the frame. My apologies to the draftsmen that see this for cross hatching direct views and not hatching sections. It just seemed to better highlight the important parts!

For a fairly simple clamping concept, it required quite a few parts. This picture shows (top to bottom) a pair of spacers which hold the bolt head near the bed surface, one of the stop plates, the two swing clamps with their nylon friction blocks,  the doubler plates that are positioned inside the hat section, and the other stop plate.

I had to drill two holes in the bottom of the bed to access the bolts that activate the clamps.   To actuate the clamps, I use a tee handle allen wrench. This view is looking down over the left fender. The front of the bed is to the left, and the left side of the bed is at the bottom of the picture.  The hump in the floor is clearance for where the gas filler pipe used to run.

This shows the bed as it is clamped down. The grey swing clamp is tightened against the bed mounting bracket.  To open the bed, loosening the bolt will loosen the clamp until it can swing by the friction of the nylon block.  After it swings to the other stop, clearing the bracket, the bed can be opened. This view is looking straight up on the passenger side, with the cab to the left.

After I completed these clamps, it was wonderful to drive the truck without the constant rattle.  It was really very quiet.  The truck seems to be "tighter" now than it was when powered by the gasoline engine.

Additional Instrumentation

I decided to enhance the instrumentation package by adding an E-meter, digital voltmeters which monitor each half of the battery bank, and a digital voltmeter to indicate the status of the 12 volt battery.  The E-meter keeps track of all the current entering and leaving the battery pack and is in effect a fuel level meter.  It also has many other functions to assist in monitoring the battery bank.  The meters on the two halves of the battery pack are to make sure that there is no battery or connection going bad.  If something does start to fail, it will affect the voltage on only the half of the pack where the failure is.  By making sure that each half performs the same as the other, you are almost assured that things are OK.

Shunt installation

The first problem installing this additional equipment was installing another shunt in the main power circuit.  The E-meter requires a current shunt which monitors all the current going into and out from the batteries.  It must be the only thing attached to the negative terminal of the battery pack with all the connections made to the other end of the shunt.  The only logical place to connect this is directly on the battery.  The original cable going to the electronics board is easy to connect to the shunt instead of the battery.  Connecting the battery terminal to the shunt is a problem.  They are located so close that a standard cable cannot be fit in.

This is my most negative battery (battery #1).  I need to install the new shunt between the battery terminal and the black battery cable (and smaller charger cable).  As you can see, there is not much room!

I decided to make a copper strap to do the connection, but have no good local source of copper bar.  I decided to make my own from copper plumbing pipe.  I took several lengths of 1/2 inch hard copper pipe and softened them by annealing.  I now flattened them forming copper bars about 1/16 inch thick and 1 inch wide.  

To get the current capacity I wanted, I decided to stack three of these bars.  This gives me a cross sectional area slightly greater than the 2/0 cable I have been using.

I have made three soft copper straps by annealing hard copper pipe and then flattening them.  I did this by heating the copper to a dull red glow and letting it cool.  This makes the copper dead soft.  I then totally flattened the pipe into 1/16 x 1 inch bars, which I formed into nesting arcs..

I then nested the three strips and soldered the two ends.  I did this to minimize contact resistance.  Leaving the middle part of the strips loose allows much better flexibility.

The shunt is installed.  The cables  removed from the battery terminal are now on the close end of the shunt.  The fabricated copper strap then connects the other end of the shunt to the battery. The screws on the top of the shunt blocks are where the signal leads to the meter will be connected. I still need to make an insulating boot of some type to cover the shunt, strap, and battery terminal.

This is the original post cover with access and clearance holes added.  Over half the wires are in place in this picture. The voltmeter and ammeter are very short gauges and only needed a small hole for the wire access.  The E-meter, which mounts in the bottom hole, is long enough that I needed a small amount of additional clearance behind it.  That is why the bottom hole is so large.

The wiring has been finished and the pod installed.  The white tubular devices with red on the end are the meter lights for the voltmeter and the ammeter. There are quite a few wires for the E-meter.  Not seen in the E-meter hole is the DC to DC converter which isolates the 12 volt power from the regular 12 volt system.

The E-meter has been wired and is ready to be installed into its opening.  In the back of the cavity, you can see the DC-DC converter (with the yellow shrink sleeve).

Here the gauges are installed and ready for use once all the wires still hanging under the dash are properly connected. I spent a lot of time trying to figure out a good way to fasten the gauges in the pod.  The clearance around the guages is not adequate for the standard mounts.  After I removed the ammeter and voltmeter from their temporary mount, I discoved that they are "push fits" into the holes and really don't need any more support.  I wrapped electrical tape around the front of the E-meter until it was also a push fit.  This simplified life tremendously as I was then able to wire the meters outside the mounted pod and then just push them into their holes.

I mounted the prescaler and the 3 fuseholders in the DC compartment of my charger monitoring meter box. The prescaler is the black object on the back wall of the front compartment.  I ran more wires than I had planned the length of the cab. These wires run in the barely visible loom at the lower right corner of the pictue. Since taking this picture, I have removed all wires from the left hand fuseholder and now use it as a spare.

This diagram shows the wiring for the gauges installed on the windshield post.  The voltmeter and the ammeter were just moved from their temporary locations with the wires extended.  The E-meter involves quite a bit more wiring.  The 6 conductor cable shown at the bottom goes to the center of the dash where the digital voltmeters will be located.  Some conductors will be feeding these meters, others will be picking up required external circuits, and some will do both. The three prescaler wires at the bottom are routed under the door base molding back to the charger meter box. Battery monitoring digital meters Below is the diagram for the digital meters I installed to keep tabs on my battery condition.   I had originally planned on a three meter package with a separate meter for each half of the traction battery pack plus one for 12 volts, with all three meters turning on with the ignition.  I decided to go with a somewhat simpler switched two meter system, one for high voltage, and one for low.  This made the packaging much easier and solved a couple of potential problems I have been concerned about.  This implementation leaves all the power off the meters unless the switches are specifically turned on.  I now don't need to worry about having excess brightness at night or leaving power on the meter leads at all times.  I will also have better accuracy as the two halves of the battery pack are measured with the same meter, not two that might be calibrated slightly differently. .

This is the connection diagram for the other end of the cable and the digital voltmeters.  The first meter will allow me to compare the voltage of the first 10 batteries with the second ten by selecting the bank with the 4PDT switch.  Any differences will be a sign of problems developing.  The second meter monitors the 12 volt lighting battery. .

The meters and their switches are mounted on a 1/4 inch thick fiberboard panel which mounts on a piece of 2 x 4 which is hogged out for clearance. The small black chip with the yellow shrink sleeving is the isolated DC to DC converter which supplies the working power for the high voltage meter.  The low voltage meter only has 2 leads and is powered by the circuit it is measuring.

The assembled meter housing totally encloses all the wiring. The left hand meter reads either the upper or the lower string of 10 batteries as selected by the 3 position switch above it. (Center is off.) The right hand meter reads the 12 volt battery voltage whenever the switch above it is on.  This allows checking the battery at rest or with the main DC to DC converter charging it. The light in the center is the motor overheat warning light, which flashes between red and blue when lit.  (The LED came that way!)

I mounted the meter assembly on an aluminum strap which attaches to the dash using a couple of the original screw holes. As I will only use these meters on an occasional basis, the low mounting should not be a problem.