Conversion of Oliver 1800 using Nissan LEAF components

My project is progressing - slowly - work and farming took priority this summer. I got the hydrapower (2 speed transmission) torn apart and decided to keep the housing to hold the flywheel/clutch. I removed the jack-shaft, gears, hydraulic pump and, with some help from a machinist, the input and output shafts are now just coupled together. Unfortunately it will take up a lot of space, but it's simplifying things to keep it.

I also got a crank-shaft substitute made that the flywheel will mount to. A flange bearing and pillow-block bearing will hold the shaft.

I'm currently thinking of of just direct coupling the leaf motor to the flywheel shaft with no gear reduction. I'm concerned that when running the PTO on the tractor I'll have to run the motor at a low 2000 RPM - not it's most efficient. If it turns out to be an issue then I'll peruse modifying the leaf gearbox. I gave up on the idea of using belts and pulleys to get the desired ratio - would require a lot of space for all that.

Now that I have the tractor almost ready for mounting the motor, I'll work on disassembling the salvage-leaf over this winter.

Here is what I'm working toward for holding the crank-shaft substitute, and motor mount frame: The chain coupler shown is what I'm planning to use for the leaf motor.



Below is the modified hydra-power without any gears or pump. I kept the clutch-pack (the big thing in the middle of the opening) but tweaked it such that the clutches won't slip. It was easier than trying to make a coupler for the input and output shafts. I'll still need to fill it with oil to lube the bearings.


Crank-shaft substitute shown below, with flywheel attached. I still need to cut it to length and have a key slot cut for the coupler.



Got the flange bearing mounted to the bell housing. Mounted it into the tractor to get the rest of the frame aligned. Next step is to get the frame welded up like the cad drawing above and the pillow-block bearing mounted and aligned. Then put it all back together with the flywheel and clutch attached. Someday I'll find a way to cap the oil-filter on the hydrapower that isn't needed anymore. For now, the filter keeps the dirt out.

The tractor is pretty much ready for the motor now. I bought a leaf motor coupler from @Bratitude and had my machinist turn it down to 1.5" and 3/8" keyway cut to fit inside a chain coupler. It came out nice, here it is not pushed in all the way. I still need to get the coupler hardened - has anyone had that done, how important is it?



Below is the frame I built with flywheel and clutch mounted. Painted red - cuz that's the paint I had on hand. Donor leaf is in the background along with the 2-speed (no longer a 2-speed) with bell-housing that it attaches to.



And here it is installed in the tractor. I also reinstalled the steering mast and hydraulic lines - mainly to keep dirt out of them. 2 hydraulic lines go to the power steering, and 2 up to a cooling loop that is in front of the radiator.


My plan is to focus on the leaf next. Need to get the AC refrigerant captured, but will have to haul it somewhere for that. In the meantime I am learning more about CAN bus and hopefully be able to spoof/mock components I don't need in order to keep the VCM/BCM, etc happy. Thinking I can do that work while the car is operational.

electro wrks said:

It looks to me by the way the ICE is solidly bolted to the frame, it contributes to the beam and torsional strength and rigidity of the frame. Without this contribution, the remaining frame structure may be stout enough to handle he forces applied to it. But, you should watch for excess flexing of the frame that might lead to cracks forming. In this case, an additional structure may need to be added to the frame to strengthen it and make it more rigid.


This is a bad idea with a motor designed to turn up to 10-12k RPM, at maximum power. I don't think there will be enough power reliably available at such a low RPM. Also, if you try stepping up the motor RPM to get more power, with this direct drive to the stock flywheel, you could run a serious risk of the flywheel coming apart.

A slow turning, large diameter DC brushed motor would be a much better fit for this kind of simple, direct drive set-up. The motor control is also much simpler. You should check the used forklift motor market.

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Thanks for the things to think about. I agree that the engine probably did provide some torsional stiffness to the frame. I'm counting on the fact that this frame is very beefy - at least 3/4" cast iron in a curved L-shape. I don't plan on having a loader attached, so hopefully its strong enough for tractor weight. If it is an issue, I guess I would need to build some sort of structural frame in the ICE's place... yuck.

The frame has 4 large mounting areas - 2 on each side that I think was intended for a loader to mount to. I'm thinking I'll use those to mount a battery box on each side.

Regarding the RPM issue - I originally was planning to gear it down to allow the motor to run in the 6-7k range (3:1 ratio), but then someone had pointed out the torque curve of a leaf motor which is 187 ft-lb flat up to 3k RPM. Comparing that to the Oliver 1800 spec of ~133 ft-lb - I didn't see the need to gear it down, as long as I keep the RPM's in a safe range.

I will have to give some thoughts on how to limit the RPM to avoid having things fly apart. As I tinker with the CAN bus maybe I'll discover something that can limit the RPMs.

Made some progress over the holiday week:



Before taking the donner car to a local shop to get the AC evacuated, I used it to run the tractor's drivetrain enough to see all the mechanical components spin. And also tested the hydraulic system, replaced filters and pumped out the hydraulic fluid to change it. This tractor has no drain plug for the hydraulic fluid - you have to attach a hose to a remote and just run the pump until it sucks air. I originally made this PTO-to-wheel adapter to try and start the ICE engine that was seized - but never got it to turn. It may still come in handy someday if the power goes out - might be a way to charge a car using re-gen (from one of my ICE tractors).



Car on the way to get it's AC drained. Just barely fit on my 12' trailer. I still feel bad tearing this car apart - it drives just fine, just side impact damage. Not wanting to load it up on the trailer to bring it home, I just drove it home.

Now on to pulling the battery pack out. My first challenge was just trying to figure out the safety disconnect. This is different than all the other ones I see on the internet. If the intent is for this to be easy to use by first responders (which I thought was the intent) then Nissan really failed on it. It took me a good 30min to figure this out and get it opened.

The main battery cable was a similar puzzle/challenge - luckily I did someone's instructions on how those connectors worked.

Otherwise, besides one stubborn bolt holding the pack on (seems like the threads were screwed up when it was installed), things went well just using 4 jack stands, one floor jack, one transmission scissor jack, and a homemade dolly. Was able to lower the pack onto the dolly and roll it out:



Hope to pull the batteries out of the pack today to store in my attached garage to keep them from freezing this winter.

Battery pack opened - found using an oscillating saw worked well for cutting the adhesive.



However.. now that I have it opened, I'm playing around with the top cover to see if I could just use the entire pack under the tractor, at least to get things up and going without spending a lot of time re-configuring the modules. Once you take a look inside one of these packs, it is clearly going to be a lot of work to replicate everything in new battery boxes (I was planning on 2 boxes, mounted on each side).







Seems workable... The power cables will come out the rear, which will make for routing them around back to the motor. The slope of the tractor frame makes it work better to put the bulge to the front. But cable wise, it would be better rotated 180. There is a big bolt hanging down hits the top of the cover - that is used to adjust the height of the 2-speed gear box. I would like to remove that bolt to let the battery to go up a bit higher. But would need to find a different way of supporting that 2-speed.

Rotating the battery 90 degrees has some appeal - easier to mount with the mounting brackets under the tractor instead of off to the sides. It also sits up higher with the saddle fitting under the belly. But I really don't like the HV lines coming out the side where they could get damaged and touched. It's also off-balance - not that this tractor would care. So probably going with the above idea.

Last week I was able to get the motor mounts done and motor temporarily mounted, alignment all seemed okay. Removed the motor to get it the frame painted up, but then it snowed so I didn't get it mounted back up to take good pictures.

This weekend I reached what for a while seemed like an impossible milestone - got the wiring harnesses removed from inside and outside of the Leaf. Along with the VCM/BCM, etc. What a chore that was - took me two days to remove all the dash and stuff. Hopefully next I can do some bench-testing to see the motor spin outside the Leaf.




I ended up cutting three cables - ones going to the drivers and passenger doors - couldn't figure out how to disconnect them. Probably would need to remove the door and do it from the outside. I don't expect them to be important. Also the passenger airbag connectors - couldn't figure them out. Otherwise, it is a good project for someone good at puzzles, and a lot of patients.

I attempted to get the Leaf motor running outside of the car this weekend. It was not successful, but at least I have enough of the system communicating to know what this DTC codes are and what Can bus signals are missing that I will try to emulate.

I realized that the wiring harness that goes to the Li battery also goes to the rear of the car, and is connected to the harness on both left and right sides of the car. After looking at the schematics I could find, I didn't think there was anything in the back of the car I needed. So I took a pair of tree loppers and just cut both left and right side harnesses. About 50 wires on each side! Turns out there is a brake booster backup battery in the back that is causing some DTC's and Can comm errors. Hopefully just emulating the Can messages will satisfy the system.

The parking pawl on the gear box also needed to be re-connected - otherwise the display would just say to apply the parking brake. I tried removing the pawl motor from the gear box and just connecting it that way, but it would just spin for a while and not satisfy the system. Seems like it needs to hit a hard stop to signal that it is locked/unlocked. Eventually I would like to use that motor to lock the flywheel when in park - since the brake locks on this tractor are a bit of a pain to use. So I'll need to figure how that works a bit more.

Comparing the Can bus communication from when it was in the car working, to what it is now, I have a list of ID's that are missing, and working on a program for a ESP32 CanDue that will emulate the missing messages. Some of them are not known in the database I've found, so I have no idea what they are. But I'll just generate them at the frequency they appear and see how that goes.

Pictures below look like a disaster - it is really hard to organize these harnesses. Eventually I'll open them up and cut out anything I don't need - not looking forward to that chore.

I'm continuing to work on spoofing the CAN messages for missing components. Latest work was around the intelligent brake unit (which I don't have connected). I've gotten rid of a lot of the DTC codes. But still have at least one that is preventing the EV/HEV system from being happy (DTC P31A0). I'm hoping once that one is fixed that the it will allow the battery system to run on.



From what I read, P31A0 is caused by an issue with the intelligent brake messages I'm sending:


Not exactly sure how to go about determining which CAN message I don't have correct, and that is sending an error to the VCM. I'll double-check the messages I'm emulating and hope I just have a bug.

Otherwise I may reconnect the brake unit and cut the CAN bus wires to it and connect a Can-Due device between it so I can tell what messages it is sending to the VCM. Once I do that then I can go back to my "working" scans and compare those messages.

If anyone knows where I can find out more about the P31A0 code, please let me know - I couldn't find much on the web.

remy_martian said:

What does the wiring diagram say as far as their routing?

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The round (low-volrage wire) connector to the battery box shows the 6 (plus shield = 7) grounded wires (highlighted below). And the harness diagram showed me where those were routed - which was up into the cabin around the drivers seat and to the pillar behind the seat. I had cut the main harness behind where the battery low-voltage wires came into it thinking they all ran forward - to the VCM, etc. My mistake was not realizing the ground wires ran the other direction - to the rear. Anyway, all is good now that I know that. On with the next challenge.

Next challenge is to figure out what to do with the parking pawl motor. The leaf-system won't run without it connected, AND needs it hitting a stop at something like 30 degrees rotation both directions. I eventually want to use this to hold the tractor from rolling. I'm thinking of using the, now vacant, mounting hole where the ICE starter motor went. Having the parking motor turn a lever that engages some teeth that mesh with the flywheel ring-gear.

The shaft that goes into the parking-motor has splines which means either using the shaft from the gearbox, or hopefully I can get a machinist to make something. If I can get something made I'll go that way so I can get it the length I want, etc.



Here is a first-grader drawing of what I have in mind, and picture of the starter hole it would go into:



Another thought would be something like how the starter motor worked - a spiral splined shaft that would engage a small stationary gear into the ring-gear. Unfortunately the tractor didn't come with the starter (my guess is they removed it to hide the fact that the engine was seized...) Otherwise I may have been able to use parts out of it for this.

Anyone have other thoughts on how to do this?

First I'll get a splined-shaft made and hopefully I can at least get a defeat-mechanism in place so I don't have to keep the gearbox attached just to run the system.

I created a bracket to hold a shaft going into the parking pawl motor today. I created the shaft from a 1/2" bolt - using my drill press and machinist vice with a carbide cutter to shape a rectangle on the end that will fit into the splined end of the motor. The rectangle ended up being 7.44mm X 6.2mm. It had a little play, so perhaps one of those dimensions is a little small. I did a heat treatment on the end just in case the corners were not strong enough to hold shape. This little gear motor is pretty darn strong as I found out trying to hold the shaft with some vice grips.

Not sure how yet how it will mount on the tractor to hold the flywheel. But not important right now, just wanted this bracket in place to allow the VCM to to operate the motor without the gearbox.

Some pictures and a video:




Video of it operating, and my rambling about it:

I finally figured out why my "EVTV ESP32 CANDue" Can bus controller would get the CAN bus into an error state and stop sending/receiving messages. Turns out the board includes terminating resistors that unfortunately have to be unsoldered to remove (tiny little buggers). As most other boards include jumpers that enable/disable the resistors, they didn't provide that convenience on this guy.

Seems to be working well now. I ordered a "Teensy 4.1 Triple CAN Bus Board" which has 3 CAN bus ports. My plan is to use two ports as a CAN-bridge on the EV bus to modify messages coming from the VCM. And the third port to send the Car-can-bus messages for the missing ABS/brake/AC messages. The EV-bus bridge will allow me to do RPM/torque limiting and hopefully a "cruse control" (governor). RPM limiting by modifying the torque request messages and preventing them from increasing torque if RPM is above the tractors normal/safe limit (3k or so). And similar with cruse control to keep the RPMs steady by adjusting torque requests.

I had hoped to use the VCM's cruse control but so far I can't get rid of the brake error lights - which I assume are causing it not to function...

I implemented a speed controller using an Arduino Teensy. Allows me to set the desired RPM and it will apply torque to maintain a constant speed (governor). Also got rid of some of the extra wiring and components. Here is an updated video, next step is to see how it runs in the tractor (tomorrow).


Motor is installed now, will hook up the battery tomorrow and give it the first test spin (not driving).

Another milestone today - powered up the leaf motor installed in the tractor. After some tuning of the PID speed algorithm it worked nicely. Hydraulics all seem to function as well as PTO. Given the battery is not mounted to the tractor, I still can't actually drive it. Mounting the battery box and building an electronics box is next up.