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Discussion Starter #1 (Edited)
I'm looking for the correct SR for asking for help in picking parts, since I have a donor car that just had a motor die on it.

If this is the right place, here's what I'm up against:

My 2001 Jeep Grand Cherokee 4.7L engine just died last week, and I was looking for a replacement engine, it costs 1,600$ from junk yards local to me, or 1,200$ from ebay. Problem I find with local options is that it's going to cost a lot of time, and I'm at the moment unable to maneuver a V8 of that size to do the work on my own, and it's time consuming for such a large engine if I hurt myself, since time off work will cost much more than the vehicle is worth. I have plenty of other vehicles for daily driving, this Jeep is only driven maybe 3 times a year, and off road. It's really useless.

So my thought with my drives to Mexico every year is that I use the Jeep as a glorified covered Trailer, but with a proposed fancy feature; It could be DRIVEN to be parked on my driveway. There's laws in place to prevent people parking trailers, and having a trailer hidden as a Jeep seems like a great way to bypass this law, and make it rather easy to have an electric motor help it park.

I'm living in the San Antonio TX area, and i've already started stripping out the engine as I will be using this as a flat towed vehicle to Mexico then to Panama. I will be using it as a nice fancy sleeping cabin for my kids when on a property I trust, and maybe use it for charging phones, the purpose I don't think is too important.

My problem: What AC motor could I use that's good enough to move the Jeep. Speed isn't the issue, it's for either driving around the block, or to park it into the driveway with powered systems. Also, I'd like to try and future proof it by having it have a range of maybe half a block to start with, and upgrade by just adding more batteries in parallel. I honestly will never drive it, and will just used the motor to help the car parallel park if I'm driving the car to some foreign city, or to park it up a small hill in Panama to store it on a property where my truck can't navigate (serious problem I don't want to get rid of). I'd LOVE to somehow attach a tesla motor to the 4x4 transfer case, and grab the smallest capacity battery that can power it, and get the electronics for it. I'd love to keep it inexpensive, so that I can get the motor, pedal, and motor controller for as low as possible. If the cost of a tesla motor + accessories to make the motor spin forward or backward is too high, then something that can handle tesla batteries so that I can purchase some cells from ebay, and attach as needed in the future. I'm not needing this trailer to move fast, if it's slow and steady, I could do that as well, this is a future proof project that if it turns into a full fledged offroad EV, I could do it in 5 ~ 10 years when batteries get cheaper or better chemistry is invented/discovered.

Throw some ideas, try to keep them under $3k for the motor, controller, pedal, batteries. No I'm not worried about steering being a problem, I can buy a hydraulic pump that can be powered by a deep cycle 12V battery, it's not an issue for the next decade.


I've browsed around Ebay for batteries;

Teslas are too expensive, and seem like great ideas. 1,000$ each 24v module
C-Max batteries are large, and have a large capacity, and seem economical. I don't need much range, so capacity doesn't have to be large. 350$ https://www.ebay.com/itm/202321528648

Would 5.5AH be enough to move the motor and drive the car around the block, and no more? That'd be great!

I saw some 5KW AC motors from 300$ to 1000$, but I have no clue how to pair up a motor controller with a motor. I'd like for the motors to be able to go into reverse without needing a reverse gear of some sort, as I would love to have the motor mount directly to the transfer case, and avoid the transmission completely. And would such a motor be able to move the car in 4x4? I hope to have the Jeep stripped out in the next 2 weeks.
 

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When I moved my project car into the garage, I just used the starter and the one battery. I have a fairly steep but short driveway and that was enough to get the car up and in position. The heads were off so there wasn't any compression to fight against. In your case, I'm not sure I would want keep the block, even if all the pistons were stripped out of it and just the crank was left, although that is an option.



Bill
 

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Discussion Starter #4
I never thought of just using the starter. I could remove everything and break off the engine into pieces leaving the starter mount in place only. I guess I would just need to attach one of those electric sewing machine pedals to the starter relay and put the car into gear. And if I need anything more, just mount a stronger ele tric DC motor to the flywheel, is that about right?

I was hoping to get rid of the transmission and attach something to the transfer case, giving me much more space for a frunk, But I'll do this to get started.

Any suggestions on what I could do after? So I could roll it down the street?
 

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How about you just throw a cordless drill onto the tranny? They're good for a half/1 horsepower.


A treadmill motor would also work in a pinch.


Don't bother with a speed controller, just hook up the number of batteries you need, maybe use a blowdrier or toaster to limit the little bit of current you'll need.


There's lots of wrong ways to do this :p
 

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Discussion Starter #6
Yeah, I just realized that this has a LOT of potential with my duty. I'll most likely see how I just replace the starter mount with a DC motor with the value of the battery pack I choose. That would be great.

I'm thinking of wiring one of those foot pedals from one of the power wheels directly to the starter relay, keeping it simple.

Now for brakes, what kind of 12/24v vacuum pump should I use for the brake system? The power train is already figured out.
 

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Now for brakes, what kind of 12/24v vacuum pump should I use for the brake system?
None.

You'll have manual, unpowered brakes. They won't work great, since you can't really push that hard with your foot, but you won't be going fast or far, so, who cares.

I wouldn't even add another battery, just use the starter battery.

I guess I would just need to attach one of those electric sewing machine pedals to the starter relay and put the car into gear.
Sewing machine pedals, the old ones, were variable resistors that could handle about 100 watts. You'd melt one trying to drive with it for more than like, 3 seconds.

If you just want an on/off switch, it's going to be a bumpy ride and you're going to chew gear teeth, but, whatever. I guess you could put in a big resistor for a slow start, and a second starter relay in series with the first one that shorts out that resistor for full speed. Drill and add a little light switch to control the signal for the relay and mount it to your dash. :p

Again there are many terrible ways to do this, most of which will sort of work.
 

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Discussion Starter #8
I just realized something, I don't think I can do the starter method to run the transmission if it's an Automatic transmission. I recall an article long ago that this guy put a forklift motor into his honda civic, and had said that to use the motor he had to make sure to use a manual transmission, because an automatic transmission requires spooling up and have a minimum speed for the transmission to build up pressure for the plates to engage the gears.

Would the starter do the deed? or would I need something higher speed?
 

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Hi
A starter is very low duty cycle - why don't you get an old forklift motor and put that in
Here they go for $100 for a small one - 9 inch and $200 for a big one - 11 inch

$1000 will get a decent high voltage controller - but if there is a working controler at the forklift place that would do you for low speed

Then you have batteries - a Volt pack will be about $2000
Which will blow your budget but just one module would be OK and about $500
 

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Discussion Starter #11
Hi
A starter is very low duty cycle - why don't you get an old forklift motor and put that in
Here they go for $100 for a small one - 9 inch and $200 for a big one - 11 inch
It's why I came here, I don't know what to buy.

I've been suggested to just use the starter to move the car.


Here's what I have so far, tearing apart the engine still, need to get the harmonic balancer off the front of the car, then get the timing cover off, then I can get all the timing stuff off, and then remove the head. I'll most likely cut things out at some point. But the cheap sewing pedal does the right job very well.

https://youtu.be/C5CiYZwsP-o
 

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I've been suggested to just use the starter to move the car.
I mean, starters are cheap, you know how and where to get a new one. I would say plan on using one, change your mind if it melts.

I don't think Duncan read your requirements in detail, spending $6000 on a trailer just to help move it around is unnecessary. No controller, no extra batteries, and I wouldn't even waste money on a used motor.
 

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Discussion Starter #13
Hi
Then you have batteries - a Volt pack will be about $2000
Which will blow your budget but just one module would be OK and about $500
Why not a C-Max battery pack? they seem to be plentiful on ebay, 5AH each cell, and modules sell for about 350$, are they that bad?
 

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Discussion Starter #14
I mean, starters are cheap, you know how and where to get a new one. I would say plan on using one, change your mind if it melts.

I don't think Duncan read your requirements in detail, spending $6000 on a trailer just to help move it around is unnecessary. No controller, no extra batteries, and I wouldn't even waste money on a used motor.
Yeah, I was thinking that, I don't need range, and I don't need speed. I need inexpensive, and I just need to be able to park the car when I get to destinations.

I need to go to Autozone and get a puller to remove that damned pulley, so I can start removing the rest of the engine in pieces.
 

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Discussion Starter #15
Got the pulley off, trying to remove the exhaust heat shields and the exhaust piping, and I'm unable to get access to it, it's against and over the steel rails of the jeep. Looks like this isn't designed to be taken fully apart in the engine bay.

I was hoping to finish this weekend, but I don't think that will be possible.

maybe I'll just grab the reciprocating saw, and start cutting away at the engine like a mad doctor. But I definitely can't do it this late in the evening, I know cops will be coming by telling me to keep it down.
 

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I'm unable to get access to it, it's against and over the steel rails of the jeep.
Well just get out the sawzall and...

maybe I'll just grab the reciprocating saw, and start cutting away at the engine like a mad doctor.
My man.

But I definitely can't do it this late in the evening, I know cops will be coming by telling me to keep it down.
Plan it out, then do it quick and back inside. Leave it for 30-45 minutes (time for cops to drive by, see nothing, and leave) then go out and do the quieter stuff again like undoing bolts.
 

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Got the pulley off, trying to remove the exhaust heat shields and the exhaust piping, and I'm unable to get access to it, it's against and over the steel rails of the jeep. Looks like this isn't designed to be taken fully apart in the engine bay.
True. Few cars or light trucks can be fully torn down in place.

maybe I'll just grab the reciprocating saw, and start cutting away at the engine like a mad doctor.
This whole idea of chopping away at the block without a real plan or an understanding of what is inside the engine and what would be needed to keep the starter motor working seems like a huge waste of effort to me. I doubt anyone who has worked with engines would consider cutting through major components (the block or the crank, for instance) with a recip saw.

And then there's the problem that you're right: the automatic transmission won't work for this purpose.
 

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Discussion Starter #18 (Edited)
This whole idea of chopping away at the block without a real plan or an understanding of what is inside the engine and what would be needed to keep the starter motor working seems like a huge waste of effort to me. I doubt anyone who has worked with engines would consider cutting through major components (the block or the crank, for instance) with a recip saw.
I have an understanding of what's inside an engine, my only thing is I don't know what's inside the Jeep engine. My work on engines has been limited to Toyota Corollas, Solaras, Camry, Honda Civics, Fits, and Accords.

This is my first attempt at something so large, and I own a 2013 Chevy Silverado 3500HD, which I don't believe I'll ever be able to tear apart, other than to change the bed.

With the suggestion of "run off your starter" is to tear into the block and the crank shaft up to the first bed, were the shaft runs through. I was thinking of keeping the flywheel, but with the issue of the transmission not able to do what I want;

Does it really matter what I am going to save at this point? I'm just removing the engine until I get some sort of plan on what motor I can use to bypass the transmission, and just go for the motor going on the transfer case.

And then there's the problem that you're right: the automatic transmission won't work for this purpose.
well, darn. But my work of removing the engine still needs to happen. And at this point, removing the transmission as well, since I can sell that along with many other parts. The engine is no good, and will need to be recycled, in pieces.


Still, I need a choice of a motor/controller to handle moving the Jeep directly from the transfer case. I'll work out the coupling part, and how to brace the motor. Unless I need to get a transmission that I can attach to the transfer case to allow reverse, forward, and park, I honestly don't think I need that, if a motor controller can do that, except the park feature, which I have no clue if I need that, unless I just add an actuator that just engages a gear to prevent the gear from moving.


This evening I didn't use the reciprocating saw, but I did make a plan on how to cut off the exhaust headers by lifting the valve heads a bit, and cut past the valves and cut the bolts holding the exhaust in place, once cut, I can just lift off the valve body parts and toss as needed. I'll need to cut out the exhaust from under the car, all cabling from the O2 sensors are gone already, and I'm almost done. Tomorrow, that reciprocating saw may need a new pack of metal cutting blades. Anything to not get an Engine Hoist.

I'm also liking that thread by JackBauer, he made his own motor controller, wonder if the motor controller supports reverse. If so, I may just use his method, and what ever 9" fork lift motor he's using, I didn't catch a model number, or something to search for on Ebay.
 

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Unless I need to get a transmission that I can attach to the transfer case to allow reverse, forward, and park, I honestly don't think I need that, if a motor controller can do that, except the park feature, which I have no clue if I need that, unless I just add an actuator that just engages a gear to prevent the gear from moving.
Again, a non-issue. Keep the tranny if you want, it's auto but, at jogging speeds you'll be fine.

If you want to get rid of it, you can electrically reverse either by switching voltage electronically, or, by using a pair of contactors (one can be the one you've already got) to reverse both positive and negative. You can do this while the motor is off, so, you can get away with lighter contactors. But if you're an auto guy and can swipe a bunch from the junkyard, you're fine. Solenoids are a lot easier than a whole tranny or a fancier controller. (Erm, your contactors have to be double throw, starter solenoids might not have a terminal at the unactivated area).

I'm also liking that thread by JackBauer, he made his own motor controller, wonder if the motor controller supports reverse. If so, I may just use his method, and what ever 9" fork lift motor he's using, I didn't catch a model number, or something to search for on Ebay.
Make your own decision, but, I'm going to all but insist you not spend a goddman dime on your shitbox project. You don't need any of that superfluous shit. You are functionally looking for something as strong as two buddies pushing your car to help you park. Just use the starter. If you melt it, oh well, upgrade later.

Damien's controller will work on your starter motor too, if you're worried about speed control. A DC series motor is a DC series motor. But you don't need it. Two modes, slow, and fast, should be fine. Buy an old hair drier, stove element, toaster.. anything that makes heat, and use that.

Don't overthink this. Don't overcomplicate it. You're looking for minutes of runtime over the next decade.
 
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