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Discussion Starter #1
I'll try to keep this as short as possible, but following the sticky's format here's some background for starters. I work as a commercial electrician in a state that doesn't really have any kind of ev community from what I can find. I have a solid understanding of electrical theory and safety from both my time in college working towards a physics degree, and my electrical apprenticeship. My experience working on cars is only slightly more than changing my oil, although over the last few months I've developed a burning passion for all things automotive. Doing my own maintenance just isn't enough for me (at least on the mechanically sound Corolla I drive now) anymore and I pretty much NEED a project, so I'm really not afraid to dive into anything at this point.

I want this project to accomplish two things. Firstly it needs to serve as a material hauling/utility vehicle for the ~100 acre (former) golf course my family has recently bought. My parents are planning a series of construction projects on parts of the property only accessible by cart path, and will be needing to transport several hundreds of pounds of lumber/building materials to and from various places on the property. For this purpose I'll try to set a modest goal of hauling around at the very least 500 lbs of material (+vehicle and two people) at 10-20mph for 2-3 hours of total drive time throughout the day. Being a golf course there are quite a few elevation changes, some very steep, but lets just say it needs to be able to handle a modest incline while under full load (without worrying about the batteries or controller blowing up obviously)

My second goal for this project is less need and more want. I'd like for this vehicle to be able to make the round trip from the golf course to the hardware store in town 20 miles away. These are 80% back roads with two stop lights and a couple of stop signs between point A and B. Speed limit 55mph for about 75% of the trip and 45mph for the other 25%. On the way back I'd want it to be able to haul at least 200-300lb of cargo without worrying about running out of juice.

I live in a hot and humid area and out in the middle of the property this vehicle will be the only source of power, so I'll go ahead and tack on the requirement that it have enough battery capacity to run an air conditioner through both of these use cases.

Based on my goal of having the vehicle road legal and capable of decent speed AND capable of hauling material at low speeds, a small manual transmission truck seems like the logical donor. So after about 1 minute on craigslist I managed to find a 2wd 1997 Ford Ranger XLT 5 speed manual seemingly in good condition. I haven't gone to see this vehicle yet, but supposedly the interior and exterior are in great condition despite its age, the only problem with it being a recently blown engine. I'm confident I can get this truck for $500-700, which seems like a great deal as long as the interior and exterior are in as good a condition as the owner says, and the transmission and suspension aren't totally shot.

I'm not sure exactly what battery technology would be best for my purposes, but considering I'm trying to keep as much bed space and hauling capacity as possible for material, Li-ion seems like the only way to go. I am however not sure if it'll be prohibitively expensive to have the capacity and utility I want in such a (relatively) large truck with Li-ion cells. It seems like salvaged leaf/volt battery packs are the gold standard of batteries these days, but I'm seeing conflicting (probably outdated) information about LiFePo4 cells being the most affordable/safest option?

On the note of affordability I saw the thread about using used motors from forklifts and was wondering where one might be able to source such a thing? I know of a few places that rent out large equipment like that in the area, but I'm not sure if they would be able or willing to sell a perfectly good electric engine from their fleet to just anyone walking in off the street. Also not sure if one of these engines would be capable of handing the tasks I'd like to accomplish.

That covers pretty much all of my ideas so far, so now all that's left is for me to ask if it would be at all feasible to complete this project (and have it not look like complete shit) within a budget of around $6000 total. After a quick calculation using figures from the wiki (and tending towards the high side on my battery requirements), it looks like the batteries are going to suck up my whole budget and then some, but I'm hoping a salvaged leaf/volt battery pack (or 3 :D) will save this project. I've just had a hard time finding good info on whether these batteries made for small cars will be able to handle the load I want to put on them, and also how much they cost/where to get them.

If you got this far, seriously, thank you. And I hope you laughed when I started this essay by saying I'd keep it short. Any suggestions would be much appreciated, because at this point it looks like the only way to accomplish what I want to would be to buy a 25 year old (ICE) Japanese mini-truck from an importer in the next state over, and I hope it doesn't come to that haha.
 

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Based on my goal of having the vehicle road legal and capable of decent speed AND capable of hauling material at low speeds, a small manual transmission truck seems like the logical donor.
I agree. You can even start with an automatic transmission truck if you choose a motor configuration that doesn't use the truck's original transmission.

Any suggestions would be much appreciated, because at this point it looks like the only way to accomplish what I want to would be to buy a 25 year old (ICE) Japanese mini-truck from an importer in the next state over, and I hope it doesn't come to that haha.
That's not really such a terrible plan - a lot of people have done this quite successfully. I think the worst part is that these are Japanese domestic market vehicles, so the driver sits on the 'wrong' side of the vehicle. Kei trucks are somewhat more practical here in Canada, because we can bring them in at only 15 years old, so they are (presumably) in better shape and more modern (although modern design may not matter for this purpose).
 

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battery types

It seems like salvaged leaf/volt battery packs are the gold standard of batteries these days, but I'm seeing conflicting (probably outdated) information about LiFePo4 cells being the most affordable/safest option?
LiFePO4 are still likely the safest if not using sufficiently capable battery management system and other protective features, but they certainly don't seem to affordable compared to salvaged EV packs now.
 

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First, although an argument can be made that "engine" is a valid word in English for an electric motor, it would be more clear to just call it a "motor", like essentially everyone else.

On the note of affordability I saw the thread about using used motors from forklifts and was wondering where one might be able to source such a thing? I know of a few places that rent out large equipment like that in the area, but I'm not sure if they would be able or willing to sell a perfectly good electric engine from their fleet to just anyone walking in off the street.
You're looking for someone with forklifts to be sold for salvage, not an operator with only serviceable equipment.

Modern forklifts (or at least many of them) no longer use this type of motor, but you're looking for a motor from an old forklift.

Also not sure if one of these engines would be capable of handing the tasks I'd like to accomplish.
The traditional series-field brushed DC motor used in old forklifts can certainly work; you just need a big enough motor, and enough battery. Of all types of motor commonly used in EVs, it has the least desirable power-versus speed characteristics and cannot readily be run in regenerative braking mode, but it is the cheapest to buy and the corresponding controller is cheaper than an AC controller/inverter.
 

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Welcome to the forum.


I found my motor from a forklift repair shop. It is a GE 11" from a Hyster lift.

The traction motors have a splined shaft. To make an easy-to-make coupler get the pinion gear from the forklift too.

Good luck
Alvin
 

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I've got a vehicle built by Tomberlin called a "Vanish". It does everything you describe except top speed is 25mph. They are difficult to find, but I have seen some sell at auction in nice shape for $2500. The one I have I converted to lithium using a pair of 2kwh Chevrolet Volt modules tied together in parallel with a harness through the balance ports and top balance it with a cheap BMS using the original Delta Q charger that has a custom program peaking the cells around 4.05V. The other nice thing about the Vanish is that they ARE street legal as an NEV (neighborhood electric vehicle), they were all built with turn signals, horn, lights, etc. To get the range you want you would likely want to run 6kwh or 8kwh of battery, which would be easy to do. Mine has a range of 15 miles or so of start/stop farm use, I don't use it much and charge it once/month or so. It will easily haul 500lbs of stuff, and I tow a 16' fishing boat with it once in a while. My guess is if I just took off down the road it would easily go 25/30miles - range is always totally dependent on duty cycle. Good luck!
 

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I've got a vehicle built by Tomberlin called a "Vanish". It does everything you describe except top speed is 25mph.
...
The other nice thing about the Vanish is that they ARE street legal as an NEV (neighborhood electric vehicle)...
The problem with a NEV is that it would not likely be legal on the roads needed for this part of the plan:
My second goal for this project is less need and more want. I'd like for this vehicle to be able to make the round trip from the golf course to the hardware store in town 20 miles away. These are 80% back roads with two stop lights and a couple of stop signs between point A and B. Speed limit 55mph for about 75% of the trip and 45mph for the other 25%.
Generally it is unsafe and as a result illegal to drive on a highway with something that is only safe at low speed.
 

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Discussion Starter #8
I agree. You can even start with an automatic transmission truck if you choose a motor configuration that doesn't use the truck's original transmission.
I guess I've only ever seen manual transmission conversions. I think manual is still better for my use anyways because I don't want anyone to accidentally slam the gas and go into a lake on the course at 50 mph.

That's not really such a terrible plan - a lot of people have done this quite successfully.
You know when I mentioned a kei truck I hadn't even considered converting it to electric, but thinking about it now it seems like the perfect solution to my problem of battery cost. After a quick look around EVAlbum I found a few converted mini-trucks and they all seem to be around 250-300 W/mi traveling at (or near) highway speed. Fully half of what I was calculating for the ranger I was looking at! Now the only issue is finding one in the states with a blown engine or other non-issue that will help me get it for as cheap as possible.
 

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I guess I've only ever seen manual transmission conversions.
While a some people do conversions with an automatic transmission, what I was suggesting was that the original transmission doesn't matter if you don't use a truck transmission at all. For instance...
  1. using a complete EV drive unit (motor, gearbox, and differential), or
  2. a different reduction gearbox (or none at all) between the motor and the axle
The complete drive unit is becoming a somewhat popular choice, but in a conventional pickup truck that would mean fitting it under the box and completely changing the rear suspension, or putting it in the front and having a front-wheel-drive pickup.
 

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Discussion Starter #10 (Edited)
Welcome to the forum.


I found my motor from a forklift repair shop. It is a GE 11" from a Hyster lift.

The traction motors have a splined shaft. To make an easy-to-make coupler get the pinion gear from the forklift too.

Good luck
Alvin
Thanks for the response! A quick look on google maps and i did find a couple of different forklift repair shops in the state so that's definitely an option. I'm kind of rethinking the whole plan now, trying to make more room in my budget for a better motor, but I'll definitely keep it in mind (and probably ask you a lot more questions) later on down the road.

  1. using a complete EV drive unit (motor, gearbox, and differential), or
  2. a different reduction gearbox (or none at all) between the motor and the axle
The complete drive unit is becoming a somewhat popular choice, but in a conventional pickup truck that would mean fitting it under the box and completely changing the rear suspension, or putting it in the front and having a front-wheel-drive pickup.
I'm actually pretty attached to the kei-truck idea now. I think they're really cool vehicles and would actually be better for staying on the paved cart paths than even a small wheelbase pickup. To my knowledge most of them are RWD or 4WD though so the problems with a complete drive unit would still apply I assume. Are complete drive units gaining in popularity because you can take every piece from a wrecked commercial EV and save both money and time/effort instead of buying/fabricating each piece individually? I think those benefits would probably be negated for my particular case because kei-trucks are mid-engine RWD and presumably a LOT of fabrication would be needed to fit a complete drive unit into that package. Speaking of, do you know of anyone that has documented their kei-truck conversion? I'm fairly intimidated by the mid-engine aspect and would love to have some reference just for dropping the engine out at least.

That said I do expect it will take me at the very least several months to find a donor mini-truck pre-1995 anywhere in the US that would be both clean and cheap enough for what I want. Not such a bad thing since it'll give me more opportunity to save/research. I assume pretty much everyone finds their donor vehicle as the first step?

Thanks a ton for helping me work through this. I feel like I'm juggling 12 things at once in my mind, but I can hardly bring myself to think of anything else it's so exciting!

Edit: Also meant to ask about the "different reduction gearbox". Would that always be something from a (presumably salvaged) road vehicle or are there other ways of getting a gearbox that might suit my needs? Also unless I'm wrong, assuming the donor is a manual, isn't the easiest thing just to use the gearbox already attached to the vehicle? Still good to know I have options if I can't find a donor with a manual transmission (or one that's broken) especially since I'll have such a small pool of vehicles to choose from.
 

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I'm actually pretty attached to the kei-truck idea now. I think they're really cool vehicles and would actually be better for staying on the paved cart paths than even a small wheelbase pickup. To my knowledge most of them are RWD or 4WD though so the problems with a complete drive unit would still apply I assume.
...
I think those benefits [of a complete drive unit] would probably be negated for my particular case because kei-trucks are mid-engine RWD and presumably a LOT of fabrication would be needed to fit a complete drive unit into that package.
Yes, essentially all Kei trucks are RWD or 4WD; the newest have the cab behind the front axle, but the old ones are mostly cab-overs, with the engine anywhere from under the seat to behind the rear axle. If the truck has an independent rear suspension (most don't), or if you're willing to swap in the complete rear suspension from another vehicle, the rear engine truck is a better starting point for any complete drive unit that is low enough to fit under the cargo bed. A challenge will likely be that these trucks are so small that the commonly used drive units (Tesla, and to a lesser extent Leaf) may be too wide to leave room for suspension.

For a mid-engine kei truck, the drive unit from a Mitsubishi i-MiEV drive or a Smart ForTwo ED might be a good match - they don't have a lot of power, but they place the motor just ahead of the rear axle and fit under the floor.

Are complete drive units gaining in popularity because you can take every piece from a wrecked commercial EV and save both money and time/effort instead of buying/fabricating each piece individually?
Yes, the already integrated motor and transaxle is much of the appeal of the complete drive unit, especially if you want a modern high-voltage AC motor, because those production EV motors have an output shaft designed to work with the transaxle, not with the common couplers typically used to connect an industrial or forklift motor to a transmission. It certainly is possible to use these motors with something other than the original EV transaxle; there are a few Leaf motors connected to conventional transmissions in conversions.

That said I do expect it will take me at the very least several months to find a donor mini-truck pre-1995 anywhere in the US that would be both clean and cheap enough for what I want. Not such a bad thing since it'll give me more opportunity to save/research. I assume pretty much everyone finds their donor vehicle as the first step?.
There are companies in both Canada and the U.S. which specialize in importing JDM vehicles including kei trucks, and likely have trucks in stock, but they may not be the least expensive source. They presumably look for mechanically sound complete trucks, not cheap starting points for people who don't need the engine.

It seems like most people find the base vehicle first, and that makes sense because available space and other issues with fitting components could cause problems if the EV components are chosen first.

Edit: Also meant to ask about the "different reduction gearbox". Would that always be something from a (presumably salvaged) road vehicle or are there other ways of getting a gearbox that might suit my needs? Also unless I'm wrong, assuming the donor is a manual, isn't the easiest thing just to use the gearbox already attached to the vehicle? Still good to know I have options if I can't find a donor with a manual transmission (or one that's broken) especially since I'll have such a small pool of vehicles to choose from.
Yes, a conventional manual transmission is the obvious reduction gearbox, even if it is larger and more complex and has more ratios than you need. The biggest reason to use something else is just to have smaller gearbox to fit everything into a configuration other than simply putting the motor where the engine was.

Long ago there were auxiliary overdrive and underdrive transmissions that were installed behind a conventional transmission to make up for an inadequate range of ratios, but they are now rare, and the underdrives (the reduction ratio that you likely need) were always less common. There is still one that is designed and intended for exactly this application - the ev-TorqueBox - but it is quite expensive for a budget project. Also, it has one fixed ratio (rather than a two-speed, shifting between direct and reduction ratios), so if you need two ratios to cover low-speed and highway conditions it isn't a solution.
 

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... do you know of anyone that has documented their kei-truck conversion?
Although it's a relatively obvious conversion, I was not aware of a specific project. I did the same search that you likely have done, and ran across Converting a Japanese Mini Truck in Edmonton in this forum; coincidentally I live in the Edmonton area.

That build thread points to another project in EV Album: 1992 Daihatsu HiJet

Both of these builds omit the original transmission; the first one apparently uses the stock 4WD transfer case as a reduction gearbox, although that presumably cannot be used on pavement since it would cause binding.

The tilt bed on the second truck and the battery box construction photo of the first truck illustrate one difference between these trucks and a pickup: the kei trucks usually have a tray cargo bed, entirely above the tires, so they don't the wheel wells of a typical pickup. The high tray bed leaves good height for components including batteries and potentially the motor and transaxle.
 

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... kei-trucks are mid-engine RWD and presumably a LOT of fabrication would be needed to fit a complete drive unit into that package. Speaking of, do you know of anyone that has documented their kei-truck conversion? I'm fairly intimidated by the mid-engine aspect and would love to have some reference just for dropping the engine out at least.
Although technically mid-engined, most of these trucks appear to have a very conventional drivetrain layout, with the engine up front (but just behind the axle and under the cab, so mid-engine) followed by transmission and a conventional (but short) propeller shaft (a.k.a. driveshaft) to a live beam axle on leaf springs. If the cab doesn't tilt up there will be hatch in the cab floor or cargo bed floor if required for access. The engine is almost certainly removed by supporting it with a floor jack, moving the mounts etc., and lowering the jack to drop the engine out the bottom (with the truck on a lift or tall jack stands). This is actually the easiest way to do many conventional cars, and is the reverse of the way almost all cars are built... they don't actually stuff the engine in from the top through the hood opening, even if we usually take them out that way.

I believe that the Daihatsu HiJet and Suzuki Carry use this conventional layout.

A notable exception is the Honda Acty (in at least some years - I'm not an Acty authority!) which has the engine mounted transversely and just ahead of the rear axle. The rear suspension is a de Dion (beam axle curved around behind the drivetrain, and jointed halfshafts just like an independent suspension). This is essentially the same design as the Mitsubishi i-MiEV, so a complete i-MiEV drive unit might be a nice match. Ford built the Ranger EV the same way.

The Suzuki Sambar is a rear-engine, rear-drive, independent rear suspension design; I don't have any detail about this. Yes, for many years Suzuki built two kei trucks of completely different design.
 
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