I needed to tackle all the miscellaneous mounting tasks required for the many electronics units, the controller cooling system, the power brake vacuum supply, the motor speed sensor, etc.  I chose these tasks next.

Main Electronics Board Hinges

First I wanted to finalize the location and mounting technique for the main electronics mounting board.  I did several paper templates, and after firming up the design, I made a stiff cardboard one.  I determined the height I needed for proper clearance both above and below this board.  I did a rough design of the hinges.  These all allowed me to determine exactly where I needed to mount the hinges.

For a design I chose to have a "double shear" style of hinge.  A simple bolted joint between two members, one fixed and the other movable, would have worked, but not been nearly as stable.  I also decided to not allow a threaded bolt to be the pivot, with the threads acting as part of the pivot.  My solution here was to use steel tubes as the pivots.  These will be held in place using a smaller bolt through the center.

The fixed hinges were made by welding a 1 inch angle to the web of a 1 1/2 inch angle, leaving a gap of 0.140 between them.  The outlines were then cut to the desired size and shape.
 

This is the hinge on the driver side.  It was able to be mounted with a single bolt through the firewall, with a 1/4 inch backing plate. Note the hinge is designed to sandwich the movable portion between two fixed plates.

The passenger side hinge is more complicated.  As I have no access to the inside of the firewall in this area, I mounted a much larger assembly to the firewall with 6 sheet metal screws.  The angle of the firewall also made getting all the angles correct more difficult.

This shot gives a better perspective of the hinge locations.

I mounted the cardboard template to my hinges and can lift the assembly just as I will the final assembly.  I plan to mount packaged assemblies such as the controller and its interface, and the DC to DC converter to the top of the board, and my contactors, shunt, and fast acting fuse on the bottom.
 

I have made a cardboard template of the final mounting board configuration.  The hinges are attached. Although I have just pushed 3/8 bolts through the pivot holes for this mockup, the final hinge will have a tubing insert through the 3/8 holes, with a 1/4 inch bolt through it to captivate it.  This will assure that the hinges do not pivot on a threaded area, but have the full contact of the smooth spacer.

Computer and Cooling Pump Mounting

The original engine computer assembly is still going to be required for a couple of tasks on my electric truck.  It was originally mounted on the radiator overflow bottle on the right front fender well.  I removed the bottle, which left the computer un-mounted.

I decided to make a frame to mount the computer and the vacuum pump, both of which would fit after removing the bottle and moving the computer back a little.
 

This frame was made to mount the automotive computer which was originally mounted on the radiator overflow bottle.  By moving the computer toward the rear of the truck a small amount, room was left to mount the vacuum pump next to it.

After completing the frame, which mounts on the studs which mounted the overflow bottle, I started thinking about what the effect of the vacuum pump vibration would be on the computer.  I decided to move the vacuum pump and mount something else on this frame with the computer.  I decided to mount the coolant circulating pump here, as it should run very smoothly.  This pump keeps the coolant flowing through the Zilla controller and the radiator.

To make the change, I cut off a corner of the bracket and added a mounting hole.
 

After thinking about the vibration the vacuum pump produces, I did not want to subject the computer to it.  I decided to mount the Zilla controller liquid cooling pump on this bracket instead. You can see I cut out the corner and added a 3/8 mounting hole for this pump.

The computer and the cooling circulation pump are mounted on the passenger side fender.  The computer is almost in its original position, but has been moved back several inches, and sits lower.

Controller Radiator Mounting

The controller cooling radiator and reservoir was next.  I found some surplus aluminum extrusions in a modified angle configuration.  I riveted a cross piece at the top to give access to mounting screws, and bent the bottom to mount on a lower pan.
 

I made the mounting frame for the Zilla cooling radiator from some surplus aluminum extrusions.  As the junction of the top rail and the side members is sandwiched tightly between the radiator and the truck top rail, this prevented using any type of screws and nuts.  Instead I riveted them together with both ends of the rivets nearly flush.

The radiator attaches to the rails with 8 screws. The bar across the top provides mounting holes to attach to the truck top radiator rail. bottom mounting holes are in the bent portion and attach to a plate at the bottom of the original truck radiator.

The final mounting location is behind the air conditioning condenser.  Cooling air will pass first through the condenser then through the radiator.  I can mount up to two fans on the radiator if needed.
 

Here the radiator mounting is completed.  The two white circles at the bottom are where the hoses will be attached. The coolant circulates through the pump, then the radiator, then the controller, and back to the pump.  There will be a squeeze bulb in one of the hoses to assist in initial priming of the system and elimination of any air bubbles.

Vacuum Pump and Reservoir Mounting

In looking for a better location for the vacuum pump, I decided to mount it below the electronics board on the transmission bell housing.  I discovered that there was also room for mounting the vacuum storage reservoir just below it.  This is a far better location than the original one, as it puts all the equipment very close to the brake master cylinder, and should be less likely to radiate the sound as it would have on the sheet metal fender..
 

I decided to mount the vacuum pump and the storage reservoir on the same bracket, attached to a couple of transmission bell housing bolts. The bracket us upside down in this picture.  The bottom cross piece mounts to the bell housing.  The flat rectangular plate mounts the vacuum pump, and the reservoir bolts to the bar at the top of the picture.

The vacuum pump and the storage reservoir are test fitted to the bracket.

After assembling all the components, I connected the hoses between the pump, reservoir, and the power brakes.  There is one extra hose that is currently connected to the vacuum gage, but will eventually connect to the other vacuum operated devices, namely the heater and air conditioning baffles.
 

The pump, reservoir, and bracket are installed.  Most of the plumbing is in.  I have the vacuum gage on the hose extending to the left.  The final use for this hose will be to connect the heater control valve which opens and closes the various HVAC doors and baffles using vacuum.

Motor Speed Sensor Mounting

My next project was to mount the motor speed sensor.  This is a round magnet that mounts on the motor shaft surrounded by a sensor housing.  Since the drive pulley for the air conditioning and the power steering is already mounted on this shaft, I need to extend the shaft and make a bracket to hold the sensor beyond the pulley.

I decided to use a flat plate mounted on spacer blocks.  The alignment between the shaft and the sensor housing is critical.  There is about 0.050 total clearance between the magnet and the housing.  This means that a .025 misalignment will cause the magnet to scrape the housing.  My tolerances are much tighter.  I figure that I should allow a maximum of .010 misalignment.

My design was a two configuration one.  I originally designed it to have a base plate with a secondary plate screwed to it.  This secondary plate could be adjusted to provide my exact alignment.  I then decided to first try a single plate that would mount the sensor directly, relying strictly on fabrication tolerances to hold the alignment.  This is risky as there are many tolerance that add up to the total misalignment  If the results of this were not accurate enough, I would then make the secondary "floating" plate.
 

I'm boring the hole that indexes the sensor location.  The sensor has a raised ring that fits in this hole to align it, so this diameter is critical.  I initially bored it in the primary plate in hopes that the alignment through all the tolerances would be OK.  Since it was not, I later bored a similar hole in the sub-plate.

I had previously provided 3 threaded mounting holes in the air conditioning/power steering base plate for mounting this assembly.  I decided to use threaded rod, held by lock nuts to provide studs.  This made assembly easy, and assured a full thread engagement in the base plate.  After completing the basic plate, I installed it and measured the alignment between the hole and the motor shaft.  I was almost .025 off!  This amount would either just drag the magnet, or just miss dragging it.  I need to make the floating plate.
 

I used threaded rod to hold the speed sensor assembly to the base plate.  They are threaded into the holes and locked with a nut.

I made the small plate, boring the alignment hold in it as I had in the main plate initially.  I also drilled and tapped the sensor mounting holes in this plate as well as providing the 4 holes to mount it to the main plate.  I added matching threaded holes in the main plate and drilled out the old sensor mounting holes to be clearance holes for the ends of the screws.
 

This is the front view of the mounting assembly.  The small plate can be moved to perfectly center the mounting hole around the motor shaft.  It is then locked securely with the 4 screws in the corners.

.	The rear of the assembly shows the spacer mounting blocks.  The relief at the base of the mounting holes is for clearance around the lock nuts.

To be able to mount the magnet, I had to make a spacer to extend the motor shaft the amount needed to align the magnet with the sensor body.  I made an aluminum spacer with a well centered .250 diameter hole.  This spacer had to be accurate, as it is an integral part of the alignment system.
 

I needed an extension spacer to extend the motor shaft out far enough to reach the sensor.

To align the floating plate, I bolted the extension shaft to the motor shaft without the magnet.  I then used a specially made alignment tool that slid over the extension shaft and had a diameter that fit the sensor alignment hole.  Once the tool was in place, assuring the sensor mounting hole was accurately aligned with the motor shaft, I tightened the 4 screws to lock the plate in its properly aligned position.

I then remounted the shaft extension with the magnet in place.
 

I made an alignment tool to accurately adjust the floating plate.  The bore fits snuggly around the shaft extension spacer and the protruding diameter is a snug fit in the sensor aligning hole of the floating plate.

Here the alignment tool is being used to position the floating plate.

The magnet is mounted on the end of the shaft spacer.  The base of the magnet protrudes 0.130 into the sensor housing per the manufacturer's specifications. The single screw, which holds the magnet and the spacer, is threaded into the end of the motor shaft, and is retained with Loctite.

Now that the magnet is mounted, I am ready to mount the sensor housing.  The alignment should be within a couple thousandths of an inch.
 

The sensor is mounted completing the assembly.

Fastening the sensor housing in place completed the installation.

If I need to change the serpentine belt some time in the future, I only need to remove the 3 nuts holding the assembly to the studs.  When done, I can slide the assembly back over the studs and tighten it.  The alignment will not be affected.

Inertia Switch Mounting

Installing the inertia switch completed the mounting of all the loose items under the hood.
 

The last "loose" item to install under the hood was the inertia switch. This is to kill the power in case of an accident.

This is my progress through September 30, 2008
 

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