Add-a-Leaf

Today I finally got around to fixing the sagging rear end. Although I had added a lift kit, the weight of 950 pounds of batteries in the rear end was just a bit too much for them. After thinking about it for a while, I decided to get an additional Old Man Emu leaf spring to insert into the pack.

The first step, of course, is the same as the original lift - remove the old springs. Jack up the Jeep and add heavy-duty jack stands. Also, put jack stands under the rear axle. Unbolt the shock from one side, let the axle droop (being careful to avoid breaking flexible lines), and then unbolt and remove the leaf springs, with a liberal application of elbow grease.

Here are the springs next to the add-a-leaf. The new leaf is nearly as long as the whole pack, designed to support the main spring. The "pointy" end goes on the rear, where the shackle attachment is. The "blunter" end goes toward the front:


To prevent sudden explosive unspringing of the pack, I clamped it and then unbolted the center bolt. I then gradually unscrewed the clamps, allowing the leafs to separate:


And here is the pack disassembled. The add-a-leaf is shown placed between the main leaf on the left and the rest of the pack on the right:


Assembly, as they say, is the reverse of disassembly. Before assembly, though, I applied liberal amounts of grease to the new leaf. To keep the leafs aligned I inserted a screwdriver in the bolt hole, and then clamped down. When it was clamped down tight, I removed the screwdriver and replaced the bolt. I then alternated clamping down even tighter, and tightening the bolt:


And then, I replaced the leafs on the Jeep. This went a lot easier than last time - not sure if I'm better at it, or if the year of sitting on them has made the leaf pack "remember" the approximate distance between the front and rear eye:


And here is ElectroJeep, all happy and level with its new add-a-leaf. It rides very nicely, now, too!


Edit (Jul 31 2009)

By request, here is what the Electrojeep looked like before the add-a-leaf (this photo is from a post in January). It actually got a bit worse after this - I added 1.5" spacers to the front springs to get more clearance above the front differential. Unfortunately, I don't have any pictures of the whole Jeep at that point.

Pumpkin Interference, V

Man, this motor mounting project has turned into a pain... This week, I finished the motor mount I had designed last week. I cut it, welded it, bolted it, painted it, and installed it on the motor. When I went to install the motor, the trouble started... but let's step back in time first. Here are the original parts, all primed pretty:


The bolts are torqued down to 25 foot-pounds per typical specs on Grade 8 hardened steel bolts. The primer is just rattle-can metal primer. The welds are there to keep everything aligned more than for structural purposes - the bolts themselves are plenty strong to hold everything together. The two longer parts I call the "cradle" since it cradles the motor feet. The two shorter parts are called the "forks" for obvious reasons (they go around the motor mounting bushing).

I finished painting the parts (rattle-can black) and mounted the cradle on the motor. The 3/8" bolts holding the cradle on were torqued to 45 foot-pounds, along with some blue threadlocker. Those guys won't come off unless I want them to. The forks are temporarily mounted for photogenic purposes. The handy thing about the cradle is that it provides a good place to loop chain or cable around for lifting with a hoist:


And here is where the trouble began. I'm not sure how, but I measured the distance between the two motor mount bushings incorrectly. I measured it at 19" - but it is really closer to 18.5". This means it is impossible to mount both forks at the same time. In this picture, you can see that I have mounted the passenger's side fork, but that the whole motor is pushed over toward the driver's side about one quarter to one half an inch:



Because of this skew, I could not install the driver's side fork. So, I put a temporary bolt on the driver's side just to support the motor while I went back to the drawing board (this is obviously only a temporary measure):


The good news is that there is sufficient clearance between the highest point on the motor mounting system and the bottom of the front battery rack (so at least I measured *something* correctly):


After much thinking, I came up with a new design. The issues were:

• The current design is too wide
• But I can not make the fork tines shorter while still using box tube because the main 1/2" bolt head will interfere with the motor mount bushing retainer
• Additionally, the box tubing on the fork "tines" was too thick to easily get a nut onto the bolt that goes through the bushing
  
• And, I'm not happy using threaded rod - I'd rather use a grade 8 hardened steel bolt thru the motor mount bushings, and those typically only come in 6" or less lengths (unless you special-order them).
  

I finally realized that I could do three main modifications to the fork design:

• Replace the long box tubing with an angle iron
• Shorten the tines by 3/4"
• Cut the tines in half at the motor bushing bolt end to make more clearance for bolt heads etc.

So, I did it. Here is a rendering of what the completed motor mount will look like with the modified forks:


Here is an exploded view of both the driver's side cradle as well as the new driver's side fork:

And, I built and painted the new forks. Installation will have to happen some time this week or next weekend. I'm out of daylight...


You may find a PDF of the blueprints for the driver's side motor mount (both the cradle and the fork) here. Note that the passenger's side is a mirror image of the driver's side.

All this for a stupid front differential... if only I could have found a two-wheel-driver front axle and transmission...

Pumpkin Interference, IV

It's full steam ahead on the "rotate the motor 180 degrees" project to overcome the pumpkin interference. I removed the motor and installed the new mounting points and bushings:


It was not strictly necessary, but the old ones were in questionable shape, and these are heavier-duty (designed to support the 4.0 liter engine). I also rotated the profile plate 180 degrees - note that the motor "feet" are now on top:


And I cleaned up and cut all the metal pieces for the motor mounts:


I spent some time drilling holes, but there are quite a few more holes to drill and welding to do. Cooler weather is rolling in; hard to tell how much I'll get done tomorrow...

Pumpkin Interference, III

I spent most of my spare hours this week wracking my brain for a solution for the motor mounting problem. I finally bit the bullet and drew a very accurate SketchUp model of the AC55 motor, plus a drawing of the new motor mounts & bushings. I also carefully measured the distances between the motor mounts, as well as the angle of the motor (5 degrees). Using all this information, I figured out a motor mounting scheme that, although a little baroque, I think will work very well:


Here is just the left side, from behind. The new mount has mirror-image left and right sides. Each side is composed of two parts which swivel about a large 1/2" bolt. Below, you can see the two parts - one of them is bolted to the motor mounting point, and the other gets bolted to the motor. This pivot allows some adjustment to be made to the motor angle (I'll probably also enlarge the hole that the pivot bolt goes through to allow for some adjustment). The two halves will be welded together, but there are 1/2" bolts on the part that attaches to the motor to give it more tensile strength:


Here are a few exploded views of all the parts. Once I get this built accurately, I'll take final measurements and update with a PDF drawing of the assembly:

Tomorrow promises to be warm-ish (55 degrees) and sunny - perfect welding weather... hopefully I can get this completed in one day.

Pumpkin Interference, II

After some thought, I've decided on a combination of approaches to solve the motor / differential interference. First, I bought some aluminum 1.5" lift spaces and installed them this weekend (side note: I'm tired of wrestling these springs. This is the *last* time I remove / reinstall them...):


This shows the clearance gained by doing this:


That's without batteries installed, of course - with 500 pounds of lead in front, and with a new adjustable trackbar installed, I expect that clearance to shrink to about 1.5 inches (which, no surprise, is the height of the new spacer).

Next, I'll gain another inch by either rotating the motor 180 degrees or by moving the motor mounting points back (stay tuned...)

It's been really *cold* this week, so that is likely all until this weekend.

Pumpkin Interference

No, not the gourd - the differential case is sometimes known as the "pumpkin". As I was preparing to put the ElectroJeep back in the garage for the miscellaneous final things that need to be done, I took a look at the front differential - I expected the springs / shocks would have settled some after going over the curbs, etc. And I was right. The motor mount was resting on the front differential. This is very bad - going over a bump with any significant force would cause serious damage. In fact, even the 100 gentle feet I drove caused damage to the mount - see the lower left corner - bent and scarred (this picture was taken with the Jeep jacked up, so the front axle is dangling):


So, the whole thing needs to move up. I have about an inch of clearance on top:


I also need to move the crossmember toward the rear of the Jeep. This causes, umm, interesting challenges if I am to use the original motor mounting points. Here is one design, showing a heavy 1" box tubing framework that pushes the hanging point toward the face of the motor (it would all ride on a 1/2" threaded rod, shown, that runs the whole length of the assembly):


I would also have to remove most of the aluminum foot on the driver's side of the motor (highlighted in blue here). This would give me nearly two inches of clearance - and I could put a rubber "bump stop" or something down there in case of an extreme bump.

The other option, not shown, would be to rotate the motor 180 degrees so the "foot" is on top, and the motor is hanging from a support stretched across / between the two motor mounting points. But the size of the foot means that there would not be as much clearance between the differential and the motor. And I think I need all the clearance I can get...

Brakes, U-Joints, Transmission

I also finished the brakes and transmission. Because of the under-seat racks, I needed longer emergency brake cables. To change them, you pretty much have to dismantle the whole rear brake assembly. So, I put new shoes and drums on while I was at it. Here is the old assembly:


And here are new shoes, springs, etc. (on the other side):


And here is the new drum. The old drum is pretty much rust-colored:


Here are the new emergency brakes hooked up to the handle. I got two Jeep Wrangler YJ '91 or later passenger's side cables, part number 52007522, and hooked them up. I had to extend the threaded rod to meet the cables. This is all as documented on this link at 4x4 Wire. A functional emergency brake is a necessity for an electric vehicle, since there is no "compression" to act as a "motor brake":


I also installed new heavy-duty U-joints on both sides of the drive shaft, and new straps and bolts on the differential end:


Not shown, but I filled the transfer case and transmission with fluid. I used a suction device to fill the transfer case, and I filled the tranny from the shifter rod opening until it started to drip from the fill hole.

Motor Installed!

After a week of vacation, time to get back at it. Today, the task was to install the motor for real. The first step is to install the flywheel. The instructions call for 1.415" +/- 0.01" - with the modified hub / bushing, it was very straightforward to get the flywheel there:


A trick I figured out to make installing things easier was to push the bushing in as far as possible (with the flywheel installed and without using excessive force), and measure that distance. In this case, it was 1.275". This means that the hub has to come out 0.140" from its maximum "in" distance. That distance was 0.750", which means that the hub has to be 0.890" +/-1 0.01" - here is that distance shown:


It is *much* easier to measure this distance as you tighten the taperlock hub than it is to do as suggested in the "VoltsPorsche 914" manual - in that case, it suggests you tighten it *almost* all the way (so it is difficult to slide back and forth) and then adjust, remove the flywheel, and tighten for real. With the volt914, I kept moving the hub when I removed or reattached the flywheel. I like this "measure the bushing distance" method much more - I only had to remove / reattach the flywheel *once*.

With the flywheel mounted (and the bolts torqued to 50 foot pounds plus 60 degrees), time for the pilot bushing. A piece of cake, using a socket as a drift:


Here it is, installed:


Next, the clutch. You insert a pilot tool to keep the clutch properly centered when you install the pressure plate (side note - this is the last picture ever to be taken with my trusty garage digicam - it got dropped in an oil bucked right after this picture was taken):


Here is the pressure plate installed (the bolts are torqued to 23 foot pounds as per manufacturer's specs). You can also see one of the two brass bushings I bought to replace the transmission locator pins, which I cannot seem to remove from the original gas engine no matter how I try:


As part of the clutch kit, I also got a new throwout bearing. Here it is, on the throwout lever plate:


And here is the plate / bearing installed in the transmission, with the driveshaft greased up and ready to mate with the motor:


While the motor was out for this procedure, I took the opportunity to fix the interference problem with the motor mount:


Finally, with everything in place, I removed the lifting eye. This was trickier than expected. Basically, you are supposed to "tap it with a hammer" and it will slide out - this concept is well illustrated by the picture here:


However, there were complications. Either when it was installed, or during all the hoisting I've done over the past few months, a large burr developed on the heatsink fins. So, I had to take my angle grinder to them and widen the groove somewhat. And then I had to use my Big Friendly Hammer (a 6 pound sledge) with full-force "taps". The lifting eye was pretty banged up by all this, but I got it off:


Just for grins, with the lifting eye removed, I dropped my 3x1 battery box on top for a test fit:


Whew! Now, to weld the battery racks and boxes...

Motor Mount Fabrication

This week I fabricated the motor mount. I stuck fairly close to my original design, but tweaked it as I went along. It all started with 1 1/2 inch steel straps and angle stock - here is the first set, clamped and waiting to be welded (you can see where I wire-wheeled off the primer to make a clean weld):


This was my first attempt at flux-core welding (my previous welding experience was mig welding) so it is a little rough, but the penetration is good, and it is plenty strong:


I cut one side of the angle stock for the bend in the hanger - this leaves an unbroken strap all the way around. Here is the hanger cut, bent, and clamped in preparation for welding:


And here it is, all assembled. I decided not to add the forks from the original design - it would have made it so it did not rotate, and I think a slight rotation will be necessary.


After drilling the holes for attaching the motor, the next step is priming (here you can see the notch I had to cut in the hanger due to interference from the original Jeep motor mount):


Finally, it gets a coat of enamel. With all that done, here it is installed (on the left you can see how the notch fits against the mount):


And here is the motor, resting all happy in its new home:


That lifting eye has been handy so far, but the time is coming when it is just going to be in the way. Azure Dynamics' website says it is removable, but darned if I can figure out how. I'll send them email and see what they say.

Finally, after test placing 480 pounds of batteries in the front, I went under the Jeep to check lower interference. Unfortunately, there is some, with the front axle "pumpkin" (higlighted in red here):


When I remove the motor to do the final flywheel/clutch assembly, I'll take out the mount and grind a new radius on that corner, as outlined in green, to remove the interference.