Wiring up the Controller Harness

Today, I installed the last kit piece that I have from Electro Automotive: the motor controller wiring harness.


Here's the harness plugged into the controller and fed through the two-inch computer grommet from the last blog entry. ElectroAuto was gracious enough to color code every single wire to help prevent misconnects. This made the installation much easier.


The wiring harness again from inside the engine compartment before crimping on all the connectors.


Just for grins, I plugged in the motor position indicator connector and inserted the main motor drive cable into the controller to get an idea what this thing might look like completed. The motor drive cable isn't really bolted in and will probably come up through a hole in the trunk floor instead to prevent interference with the rear battery rack. Note the two black circular connector holes on the right of the controller where the battery cables will plug into.


Here's the wiring harness crimped and connected to the terminal blocks. My EV partner-in-crime Randy provided the dimensions for the current shunt that will also have to mount on this wall. Given the wiring interference, the battery rack placement and the large size of the current shunt, I'll probably have to move all this around to get things to fit. At least this gives me an idea of what connections I'm dealing with. The loop in the wiring harness at the bottom of the picture is extra slack in case I need to rewire anything.

Technically, if I shorted some of the terminals on the top block and added the 144V of batteries (along with a 12V accessory battery), I should be able to drive the car. The next major step is installing the battery racks which still need to arrive from ElectroAuto, so I have no idea when they will be here. In the meantime, I can remove the original battery tray and engine hood latch. The passenger window is also really hard to operate with the hand crank, so I might open up the door and lubricate all the mechanisms.

Just a quick note about the Azure Dynamics motor controller (DMOC445): The instructions from the FTP site said that with proper protection, the motor controller could be run off a rectified AC source (!). This means I could rectify a dedicated 120V AC outlet to generate about 160V DC to try and spin the motor. Sooooo, I contacted Azure Dynamics and they basically said to not do that and that they would update the instructions to remove that option. Well, that takes away my idea of a 20-mile extension cord to get to work...

I'm also starting to do more research on battery management systems. I'm thinking that if I can make a user-friendly system to tell people the state-of-charge for their battery packs that also monitors the health of each battery, that could be very useful knowledge as gasoline prices go up and more people get interested in electric vehicles.

Next up: Waiting for more parts and firing up the sawzall to remove the battery tray...

Spaghetti Wiring

Today was a day for really getting my brain wrapped around the initial wiring. After studying the AC kit diagrams and reading the motor controller documentation from Azure Dynamics, I think I understand a little better what all these relays and terminal strips are for.


Yay! The two six-position terminal strips that ElectroAuto promised were in the mail today. This means I can really jump into the wiring.


Yikes, this isn't pretty, but I think it will get the job done. One of the major difficulties in placing all the terminal strips and relays is that the left mounting wall inside the engine compartment is not flat in many places. To allow enough room for wire connections and put the pieces in roughly the right place, I had to angle some of them. I tried to leave a space for the current shunt (between the two circle depressions), but I have no idea how big it actually is. Randy, another 914 EV AC kit customer is going to send me a few sketches so I can move things around, if necessary. The instructions call for two of the small black relays, but I only received one, so I ran out to Napa Auto parts today to get the second one.

I keep telling myself that I have plenty of wire, rivnuts and crimp connectors in case I need to redo anything.


Here's the main wiring loom with the important wires sticking out and crimped. The remaining wires are folded back on the loom and taped in place with red electrical tape. The green/red wire drives the oil pressure light and will be tied to chassis ground on a bolt, so we use a closed terminal. The black wire is the 12V switched supply from the ignition switch. The two grey/dark-red wires drive the backup lights.

The red wire comes directly from the 12V post on the battery. It was formerly the alternator charging cable. The instructions call to add a separate 16-gauge wire to the positive battery terminal, but since this one was already in the loom, I used it instead, albeit with a thicker crimp terminal.

The directions also say to pull the black/yellow-stripe wire out of the main loom. This is a trick request as there isn't a black/yellow-stripe wire in the loom. This wire exists in the loom that travels back to the brake lights. Thus I had to add a wire and splice it into the black/yellow wire near the trunk. This signal is new to the AC version of the kit because it flashes the brake lights when the regenerative circuit is active.


Here's wiring from the main loom and potbox (large grey wire) tied to the lower terminal block.


The directions call to remove the positive terminal clamp, bolt the 12V wires together and insulate the whole thing with electrical tape. Just to keep things clean, I also removed the negative battery clamp and cable since it didn't go anywhere but into the chassis.


I finally found a solution to protect the 2" hole drilled between the engine compartment and the rear trunk where the motor controller sits. I found these somewhat deep nylon computer grommets.

Off to the upper-right is a small pouch of piggyback terminals from Radio Shack that I needed to properly follow the wiring instructions on the relays.


Here are two back-to-back computer grommets glued with liquid nails into the 2" hole in the trunk to the engine compartment. After this dries, I'll be threading through the DMOC motor controller wiring harness and attaching all the wires to the relays and terminal blocks.


Here's the current mess of wires. Most of the really loose ones are the black wires from the relays to the potbox. I suspect this will look a bit nicer after I tie wrap everything into place.


Here are the two neutral start connections to the potbox. These connections prevent the driver from starting the controller unless the accelerator pedal is fully released. I had to use an ohm-meter to determine which two of the three terminals to attach the wires to since the directions just say driver side connection and passenger-side connection.

When the driver turns the key in the ignition and the pedal is fully released, it activates the neutral start relay which turns on the motor controller. The relay is connected in a "self-hold" configuration so that it stays engaged until the driver turns the ignition key off.

I think that's it for today. I'll try attaching the motor controller harness tomorrow after the grommet glue dries. After all that wiring is done, the only other connections that are technically required are the regen-disable and power-mode connections. These will probably go up to a switch and knob in the driver cabin. If I had batteries installed, I could just ignore those two connections and the car would still operate. Getting closer...

Starting the Wiring

With the motor/transmission bolted into the chassis and all the mechanical shafts/cables attached, I'm starting the wiring. ElectroAuto sent me the incorrect terminal blocks and missed one of the smaller relays (assuming the instructions are correct), so I'll probably run out to Napa tomorrow and see if I can pick up more stuff.


Here is the first terminal block and two relays attached to the left wall behind the driver. Notice the second bolt on the left at the bottom which needs another black relay.


Here is the main factory wiring loom removed from the "multi" connector that attached to the engine compartment fuse/relay board. The connector was easy enough to detach by prying it open with a screwdriver.


Here's the main wiring loom with several of the key wires separated out to the left. The black wire is the 12V switched line from the ignition. The two grey/red-stripe wires drive the backup lights. The green/red-stripe wire turns on the oil-pressure light in the cabin.

The fifth wire called for in the AC kit instructions is supposed to be black with a yellow stripe for the rear brake lights. The catch is that this wire is NOT in the main loom and exists in the wire bundle beneath it. I'll have to cut open the lower bundle and tap into it so that the regen function of the motor controller will activate the brake lights.

I spent most of today researching the wiring diagrams in the Haynes 914 manual and comparing them to what I see in the vehicle. An interesting note is that the blue wire shown in the picture above actually drives the tachometer when given a bunch of 12V pulses. It would be great to make a pulse generator that gets this working to match the RPM of the electric motor! Maybe I can get the "low-fuel" light to come on when the pack is near depletion. Ah, fun projects for much later days. Onward to crimping connectors on the wires...

Tying Up Loose Ends

Today was a day to get rid of cruft left over from the conversion process so far. I took all the extra, un-used 914 parts lying around the house out to Craig at Camp914 in exchange for a fusebox cover for under my dash. I also returned his 12-point CV joint tool that I used to take the transmission out of the car. I sent an e-mail to Pat to return his flywheel lock tool and clutch centering tool. All the cardboard boxes from the motor, controller and several other ElectroAuto shipments are in the recycle bin.

There are few things left to finish for hooking up the transmission to the chassis:


The instructions suggest adding tie-wraps to keep the clutch and speedo cable from flying around (shown here in red before trimming).


I had originally failed to get the correct length of bolts to connect the black ElectroAuto motor mount to the original horizontal engine mount bar. The correct bolts are now properly sitting in the two recessed holes in the orginal engine mount bar. I also tightened down the four primary nuts to hold the black motor mount to the motor itself. Everything should be snug now.

Note: the original ElectroAuto instructions call for 3 1/2" bolts for the original engine mount. I found that 2 1/2" bolts were far better. I wonder if this was a typo in the directions or if there are different motor mounts on the various 914 model years.


In the process of cutting the hole in the trunk for the motor controller, I had to cut the grounding bolt away. There wasn't anyplace near enough to install a new bolt, so I simply used one of the bolts that holds the controller mount plate in.

Since the bolt head is inside the trunk and the nylock nut is under the car, I had to use a wrench and two steel blocks (pictured above) to hold the bolt in place while I worked with the nut below.


Here's the grounding strap in place under the nut. Note that I scraped the metal under the grounding strap as clean as I could get to provide a reasonable contact. Since we don't have to pull high numbers of amps from the chassis ground anymore (say, to the starter motor), I'm hoping this will be adequate to ground the transmission and electric motor housing.

Cables and CV Joints Attached

The task for this evening was re-attaching all the cables and drive shafts back to the transmission that I re-installed last Friday.

Here's a dangling CV joing (minus the protective bag) ready for bolting back into the transmission. I packed the joint with grease for lubrication and painted a CV joint gasket with grease to seal the joint.


Here we are, torquing down the CV joint bolts with the special 12-point tool I borrowed from Craig at Camp914 and my father's torque wrench.


After installing the CV joints, I installed the shift linkage and cover. I'm hoping things will be much tighter since I replaced many of the ball sockets. Thanks to my neighbor for helping hold the shift lever while I twisted the shift linkage on.


Here's the final undercarriage which is much more sparse without the gasoline engine. The speedo cable and clutch cable are attached and ready to go.

Next up: tie-wrapping things together, fixing the bolts on the electric motor mount and starting the wiring. This will hopefully be much less messy than wrangling the transmission.

Motor/Transmission Attached!

Well, today was quite productive. My friend Nicole came over for a few hours to help me finish the transmission and put the motor/transmission together.

While rummaging through my bolts last night, I discovered that I had forgot to install the flywheel bolt plate and had just put the bolts right into the flywheel. While this might not have been fatal, I'm really happy that I was able to take out the bolts (rather hard with red loctite) and install the proper plate.

Here's me torquing down the flywheel bolts again (80 foot-pounts!) after putting the proper plate in underneath the bolt heads.


With the flywheel on, I could now attach the new clutch assembly. Thanks again to Pat for letting me borrow his flywheel lock and clutch centering tool (pictured here). One mistake I made was to not push the centering tool all the way in, so the clutch was off-center by a few millimeters. After realizing this, I loosened the six clutch bolts, pushed the tool all the way in (as shown in the picture) and tightened downt the bolts to 18 ft/lbs.


with the flywheel and clutch on, Nicole and I used 2x4s and other shims that I got from Pete to line up the motor and the transmission. After maneuvering the two together, it was easy to bolt them tight. Here's Nicole putting in the bolts for the motor adapter plate.


Tightening the bolts with two wrenches to keep them from turning in place.


Here I am with the assembled motor/transmission with lots of 2x4 spacers on top of a 1/2 ton furniture dolly. Note: the kit instructions mention that the bolts that tie the motor mount in the kit to the front Porsche motor mount are 3 1/2 inches long; however, I think this is a typo because I had to go back and purchase 2 1/2 inch bolts because the 3 1/2 ones were almost exactly one inch too long.


Since I don't have a transmission jack, I chose to put the motor back in the car the same way that I removed the gasoline engine. Here's the motor on the furniture dolly ready for insertion.


All I have to do is jack up the car, slide in the motor (shown here) and then lower the car back down until the mount points on the chassis line up with the motor mount points. To make this process easier, I measured the distance from the center of the front motor mount points to the innermost transmission bolt on the chassis (approximately 37 inches). I then adjusted the motor mount bolted to the electric motor so that its mount points were also 37 inches to the innermost bolt on the transmission mount.


This acutally worked rather well, and I was able to get the motor inserted into the chassis with little physical effort. I did have some tenuous moments when I needed to insert the mounting bolts with nothing but the two floor jacks holding the car up. Most people would not recommend doing this, but I took the chance. Notice that I did put 4x4s under the rear suspension swing arms as a minor safety measure.

One more quick note, ParkRose hardware had all the bolts I needed for this; however, make sure the hardware you get out of the trays is actually the hardware you're looking for. I had to make another run to Parkrose today because one bolt from the proper bin was 1/2" too short and another bolt was the proper length, but had the wrong thread size (fun).

Update about wiring harness parts: Shari from ElectroAuto got back to me today and clarified that she still needed to send me two more six-place terminal blocks as the instructions mentioned to fill out the proper kit parts. I still have many other things to work on in the meantime, but it's good to know that I wasn't totally confused with the last shipment.

Off to go enjoy some hiking out in the sunshine for the rest of the weekend...

More Confusing Parts

Yay, I got another shipment of parts today from Electro Auto! These will help me move forward a bit more once the motor is installed into the chassis.

I'm a bit confused because the directions call for a five-terminal block and a six-terminal block with a shorting bar. What I got was a five-terminal block with a shorting bar (lower-right pice in the picture) and a four-space connector (upper right part). The negative terminal and shunt are missing, but I don't really need those until I install the heavy battery cables.

I'm going to give it a few days while I install the motor/transmission and see if anything shows up before I contact Shari at ElectroAuto.

I'm pretty tired today from other things, so I think I take a break.

Assembling the Motor Adapter

My friend Ruth came over this evening and helped get the final nylock nuts put on the potbox. The remainder of the evening involved attaching the motor mount and adapter pieces to the Azure Dynamics AC motor.

This is my fathers torque wrench from WWII. He hasn't used it in fifty years, but it works just fine!


The directions say to tighten the hex-head bolts in the cone adapter. I came up with this trick that uses two flywheel bolts and an extra box wrench to allow extra tightening of the adapter bolts.

To get the cone hub to the right depth, the directions mention attaching the flywheel, measuring the proper distance with a caliper and then taking off the flywheel WITHOUT moving the cone hub. I found this near impossible, so I simply measured the delta between how much the cone hub moved between bottoming out and the proper location. After taking the flywheel off, I bottomed out the cone hub and then moved it out the delta distance. Much easier...


And the last step for the day was torquing the flywheel bolts to 80 ft/lbs (ugh). Note the flywheel lock on the upper left that I borrowed from another Porshe enthusiast (Thanks, Pat!).

I ran out to Fred Meyer to get some Moly Lube for the needle bearing in the middle of the flywheel. Tomorrow, I'll assemble the clutch and think about attaching the whole thing to the transmission.

Fun with Rivnuts

I purchased a Rivnut gun yesterday at Parkrose Hardware. That place is amazing; they had all the hardware and rivnuts I needed. It's associated with TrueValue hardware, so people in other areas might be able to go to TrueValue.


Here's the Rivnut Gun. It's expensive($65), but I suspect it's easier to use than the tool shown in the VoltsPorsche DC manual. I didn't receive any rivnuts or tools from ElectroAuto, so (in my impatience) I just went out and got my own.


Tonight's project was installing the potbox that I assembled a few days ago. This requires taking out the cabin seats and pulling the upholstery behind the seats forward so you can access the bolt heads as they come through the wall.


Here are the two upper bolts from the potbox coming through the firewall. The bottom two are installed with rivnuts so we don't see them. I have a friend coming over tomorrow to help me attach the nylock nuts. The directions say to install the bolts from the passenger compartment side, but I found it was easier to push the bolts through this way.

Getting the bolts to line up properly on the firewall was difficult due to the rust and grime on the bottom edge that screwed up the alignment. If you go too high, you bump into the brake cylinder(see picture below). If you go too low, the bolts don't come through at a flat place in the firewall (see rightmost bolt in above picture). Furthermore, if you purchase spacers, make sure the 1/4" bolts actually go through the spacers. I spent an hour filing out the centers of the spacers so the bolts would go through (argh!).


Here's the potbox installed. I still need to add the spring, cotter-pin and 5mm threaded barrel listed in the instructions, so I hope those come later with the remainder of the kit parts. The grey wire coiled off to the left will install onto a terminal block soon.

Electro Auto shipped their first AC wiring harness to the first AC kit customer and it arrived today. I'm excited to get my own terminal blocks, relays and harness soon.

Just Cleaning Up

I spent the past two evenings getting the rest of life together. Tonight I just did some simple cleanup. I swept the garage and put away all the tools, wood pieces and garbage so that there would be space to work in.

The garage, somewhat clean again. The transmission off to the right has a fresh load of oil in it and I look forward to seeing if I have any major leaks over the next few days.


Here is the photocopied template for the potbox on the firewall inside the engine compartment just behind the drivers seat. I'll need to drill holes at point A and B.


Here's the "potbox" which tells the motor controller just how far I've pressed down the accelerator pedal. This is the equivalent of the throttle on a gasoline engine. I'll be gone for the next two days, but hopefully I can run out to get some rivnuts tomorrow and install this on Sunday.

Speaking of rivnuts, ElectroAuto has not been returning my phone calls or e-mail again, so I'm going to run out to Park Rose Hardware tomorrow and see if they have what I'm looking for. All the mechanical engineers at HP rave about ParkRose HW, and they seemed very knowledgeable on the phone, so we'll see.

Victory! Death to the old Transmission Seal!

Well, after fighting with the front seal on the transmission for a few days, I finally got it out. I tried using chemicals to melt the rubber portion of the seal. I tried using a slide hammer to yank it out. I tried using a long rod and large hammer to push it out from the other side. In the end, I scraped away as much rubber material as I could and simply hacksawed a slit in one edge to loosen it up.

Here's the hacksaw after cutting the slot. The seal pulled out with a pair of pliers after this.


The cause of much frustration over the past few days.


The mostly clean hole left with the seal removed.


Here is the new seal in place. Even after lubricating the seal and the surrounding hole with oil, I still had to use the throwout tube and a large hammer just to get it in. It took almost as much force to put in as it was to take out. I didn't even get it flush.


Here's the throwout tube installed.


With the front seal back in place, I added the rear gaskets, wetted them with transmission oil and installed the intermediate plate with gear shafts. This actually went fairly smoothly.


Here's the rear transmission cap installed. It was a bit of a trick to get the reverse gear to slide into place since it sat inside the rear cap.


Here's the shift support installed with a new O-ring and gasket. I also have a new shift rod bushing and cap over the protruding ball.


And finally: The throwout bearing installed.

At this point the transmission is fully assembled and just needs a load of oil. Yay!

Next up, filling the transmission with oil and starting on the potbox installation. Installing the electric motor and the potbox requires some rare hardware (rivnuts and hex-head nuts) that I hope ElectroAuto will send to me.