[dladd]

Alright, I’ve decided to make a re-build thread for my new (to me) 1995 Saturn SL2 EV.

I’ve been thinking about an EV for a while, and did quite a bit of preliminary research over the last few months. My requirements are modest. 50 mile range, 5 seats (only kids in the back, so weight/space is not really an issue, just need 5 seat belts), sporty-ish (0-60 in the 9 second range with decent handling), able to cruise at 65 for 10-15 miles, and be easy for anyone to drive. No tricks, no funky shifting, no heaterless/air conditioning less cars allowed here. I settled on the idea of a basic 4 door compact car with a DC motor and lithium batteries, which I figured would fit the bill pretty well. Hopefully something new enough to have air bags and shoulder belts in the rear seats, but not so new that it’s completely computer controlled.

Right about that time, I saw this post here in the classified forum. Hmm, a free roller, that could be a nice way to get started! I have always liked the first gen Saturns, and I can’t weld so there’s definitely an advantage to buying something that already has battery boxes and motor mounts made. I emailed back and forth a bit with the owner, one thing led to another and I ended up buying it from him as is. Broken motor mounts, damaged Warp9, all electrics, 48x 130ah CALB cells and all!

Definitely a ‘fixer’ rather than a conversion at this point, but it still needs plenty of work. In addition to the obvious fixes needed to repair the damage, it also has no air conditioning (which I figure I have until next summer to figure out a solution), a non-functioning (but still installed, so hopefully fixable) clutch, a Logisystems 750a controller (one of the few still working from what I can tell, but I don’t hold high hopes for it in the long run) and it needs to have another motor mount added to prevent excess rotation of the motor. In addition to whatever else I find as I tear into the car…

I set up a transport to get the car from there to here (not cheap to ship a non running car!!), and in the meantime while I was waiting I came across this thread and now have a used Warp9 in my garage waiting to be installed.

While I was waiting for the car, I also procured a big, ugly, rusted engine hoist from Craigslist, bought a hand powered winch to get the roller up the driveway (which required drilling into my concrete floor and installing a half inch wedge anchor), and proceeded to clean out a space in my garage to work on the project.

More in a bit…

 

[dladd]

Car arrived! Here’s my girls trying to figure out which one is our new car…

and here they are trying to figure out where to hook the winch line. (yes, the wheels are chocked...)

I was able to pull it up the hill into the garage without problem, I had one kid in the driver’s seat covering the brake, and the other in the passenger seat ready to yank up the e-brake on a moments notice! They took their jobs VERY seriously. Alas, there was no drama, it just pulled right up and in.

I fooled around with it for a little while, mostly making a wiring diagram and trying to figure out how everything was wired up. I also pulled the hood off, but that was the extent of my actual ‘work’ tonight. Most of the components have to come out in order to pull the motor (and replace the component shelf that was broken when the motor jacked up) so I want to make sure I’ve got a good complete wiring diagram before moving forward. Here’s a few ‘before’ pics of it nice and snug in the garage.

This is not going to be a quick project, I’ve got a lot of other stuff going on and really want this to be fun, not work. I’m also hoping to involve my daughters as much as I can (which will certainly slow things down a bit!). My hope is to get it up and running in a month or so, then take my time over the next few months fixing the little things.

I'd love to get the motor/trans out this weekend, but that's probably optimistic. We're in the middle of soccer season and the weather is real nice right now. Probably won't spend too many hours in the garage.

 

[TomA]

Good luck with the project.

Just a heads-up from a long-term Saturn SL owner:

These cars have an Achilles' heel in the transmission- there's a roll pin that retains gears in the cast differential carrier that works its way out. When it does that, the pin clips the transmission case, and the whole tranny grenades. Don't ask me how I know.

There's a pretty good overview of the problem and the various solutions here:

http://www.saturnfans.com/forums/archive/index.php/t-121625.html

There are some things NEVER to do with a Saturn SL: Never spin the tires. Never drive the car with the small spare tire on the front axle. Never use tires of different size on the front axle. Never spin one tire coming out of a corner, etc.

Since your electric motor puts a lot of torque into the transmission, and you're going to have it out on the bench during your rebuild, do yourself the favor of looking into this problem and taking it on.

TomA

 

[dladd]

Thanks for the link Tom, I found a youtube video showing how to check the pin without opening up the trans. Should be easy to do with it out of the car.

if it looks centered and OK, I'll probably just let it be. No need to open things up and make it worse by trying to fix something that isn't broken yet.

Thanks for the tip!

 

[dexion]

Good luck david.

I think in this case (at least now) the trans wasnt the cause of the damage.
The lower trans mount let go which shifted the trans up to the battery box snapping the passengerside cv joint and bending the warp9 enough to make all sorts of naughty sounds. Ill be watching with a tear in my girlfriends eye heh.

Careful in reverse...

 

[dladd]

Good luck david.

hey thanks! Hope I do the car proud.

I think in this case (at least now) the trans wasnt the cause of the damage.
The lower trans mount let go which shifted the trans up to the battery box snapping the passengerside cv joint and bending the warp9 enough to make all sorts of naughty sounds. Ill be watching with a tear in my girlfriends eye heh.

Careful in reverse...

fixing the clutch ought to help out. Or a smoother controller. Maybe both.

 

[dladd]

A bit more progress today, I pulled out all the components mounted over the motor. First I made a good wiring diagram, then started disconnecting and labeling everything. It was a shame to pull it all apart, it was wired really cleanly! Anyway, with the tray and components out of the way, I could get a good look at the motor.

In the closeup below, you can see the damage. The closer I look, the better it seems! It looks like it possibly is just that the metal screen rotated and pushed up against the terminals and the plastic connector. It broke the connector out of the case, but the terminals actually look decent, just the plastic insulators got thrashed. I may not need that second motor after all! Too soon to really tell though…

The picture below really shows how far up the motor twisted. It pulled the rubber motor mount clean apart on the right side.

below are a few photo’s showing the ripped apart CV joint (which sprayed grease on everything near it!) and the lower torn trans mount. It also completely separated.

so far so good! I just may get the motor and trans out this weekend after all!

 

[dladd]

well, no more garage time over the weekend, so not much else done. I did spend some time translating my scribbles into a readable wiring diagram. I am not an electrical engineer! But I think it all makes sense. What do you think? See anything wonky? This was a running car for over a year, so I know it works. Anything you'd change?

I did not put in the details of the heater or BMS yet, just the inputs to their 'black boxes'.

edit: hmm, I can't seem to get the .pdf to display in the post, but I think it did attach correctly.

 

[mora]

Is relay on top of 12V battery (in the drawing I mean) rated for full pack voltage (DC)? I'd change that if it is regular 12V automotive relay there.

 

[dladd]

Is relay on top of 12V battery (in the drawing I mean) rated for full pack voltage (DC)? I'd change that if it is regular 12V automotive relay there.

Here is what it says on it:

White-Rodgers
120-10571-6
Coil 12v DC Cont
120-901

this is what it looks like:

 

[dimitri]

I think Logisystems controller is at least partially responsible for the damage to motor/tranny mounts. Its notorious for lurching at low throttle due to poor design, which is especially evident at low gear like rear gear. Many people come up with kludges to limit throttle when in rear gear to avoid jumping backwards at the touch of a pedal.

So, after you fix up motor/tranny and start testing, be very careful with this controller.

 

[dexion]

yup i could drive it fine but not the GF.

David that relay energizes on 12V but holds pack voltage across the relay. It is the relay for the dc to dc converter (144Vdc in) so its not on all the time without the ignition switched. With the precharge resistor in place the dc to dc would groan and whine so I put in the relay 5 minutes after the precharge resistor went on the car.

 

[dladd]

my 'plan' is to get it up and running with the Logisystems, then do some power tests to see how it feels when running well. From that data, I'll make a decision on what controller to replace it with (higher or lower power). Unless it feels fine, then I'll just keep it.

I read somewhere, not sure where, about someone who added a resistor or something across the pot box only when in reverse, which lowered the power output when in reverse. I'll have to dig that up... That seems like it could be a good fix too.

 

[dladd]

Well, it’s basically all ready to pull out the motor, but I have to wait till the kids have enough free time to do it with me! With soccer, homework and going to a Giants game last night (gotta have priorities, right?) there just has not been time. I’ve pulled the driveshafts and got most of the wiring out of the way, but they are real excited about the actual removal part.

In the meantime, I’m thinking and planning. Cause I have to do something! So, I came up with a list of projects I’d like to do. Some of this is for now, some is for after it’s all back together and running, sort of a phase 2,3 etc. down the road.

1. Redesign the rear motor mount. Currently, the rear mount (CE of the motor) is a beefy strap clamped around the end, then connected to the stock upper motor mount location. I don’t like this setup because a portion of the clamp is actually over the inlet screen, which is not well attached to the motor itself. This appears to be what actually damaged the motor. The clamp to screen was solid, but the clamp and screen rotated together on the motor and damaged the posts and connector when everything broke and rotated. (you can see this in the photo’s on page 1). I see two options here. Either a) modify/remove the screen so the clamp is directly on the motor or b) replace the clamp with a simple CE bolt on plate that connects to the same mounting point. Either way I’ll add a lower torque bar to reduce motor rotation. This will require welding a tab to the frame, once I get the motor back in I’ll have to tow it to a shop to have that done. I’m sure the torque bar itself will be enough to solve the problem.

2. Install a blower for the motor. Maybe not needed, but I like the idea of not only extra cooling, but also the added protection of having the motor inlets covered up and fed by a filtered blower. Seems like it would help keep the motor cleaner and cooler. I’ll incorporate this in my redesign of the rear motor mount.

3. Replace the component shelf with polypropylene. It is currently clear acrylic (at least I assume It’s acrylic) which looks cool, but it is pretty difficult to work with. It’s brittle, and broken already from where the motor hit it. I thought about replacing it with Lexan, but that’s $$! And with all the wiring and components you can’t really see through it anyway, so there’s no real point in it being clear. I’ll just stick with something cheap and easy to work with, but a little more visually appealing than plywood (and quicker since I don’t have to seal and paint it).

3. Move 12 batteries up front. Right now all 48 are in the trunk, 36 in the recessed box and 12 in the trunk behind the rear seats. I’d like to move the 12 out of the trunk and up to the front. To clear out the trunk space and move some weight forward. I have not weighed the corners yet, but the car looks rear heavy. I’ll actually weigh it before doing this to confirm my suspicions that I could use a little more weight up front. The front rack already exists from when the car was lead acid, and the front to rear battery cables are already long enough to reach the front rack, so no major fab work will be needed.

4. Make polypropylene battery boxes front and rear. I’m intrigued by dtbaker’s use of 1/4" polypropylene and a heat welder and want to follow in his footsteps here with some nice looking DIY boxes. Well, maybe not nice looking, but definitely DIY.

5. Band all batteries in groups of 6 with a strapper. The strapping is just for organizational neatness and ease of handling.

6. And the biggie… add air conditioning! The car had it originally and still appears to have the evaporator and all the underhood wiring intact. But everything else was removed. Unfortunately the open fittings were not capped when the expansion valve was removed, so I assume the evaporator will be bad since it’s been open to the elements for a few years. BUT at least it should be replaceable, it’s not like I’m starting from ground zero and building an AC system. There’s plenty of room up front for a condenser, I’ll just have to decide how to handle the compressor. Either pulley off the Warp9, a second motor dedicated to a stock compressor, or a Masterflux style compressor. I lean towards the Masterflux since I don’t have a compressor at all right now, but it’s pretty steep $$ so we’ll see as I get further into that project research. Still a little time for this one, no urgency on getting aircon.

That’s it for now! Looks like we may have a few hours tomorrow after school, we’ll see if we can get that sucker yanked out!

 

[dladd]

Finally got the motor out!!! It took me a week to find the time to do one hour of work… Told you this isn’t going to be a quick (re)build.

Here’s the obligatory ‘motor hovering over the car’ shot with my helper/hoist operator,

a few more of the motor/trans, and empty car.

Hope to have the motor/trans separated cleaned and inspected in the next few days, then I’ll see what I need to do in order to get it back together.

 

[dtbaker]

3. Replace the component shelf with polypropylene. It is currently clear acrylic (at least I assume It’s acrylic) which looks cool, but it is pretty difficult to work with.

4. Make polypropylene battery boxes front and rear. I’m intrigued by dtbaker’s use of 1/4" polypropylene and a heat welder and want to follow in his footsteps here with some nice looking DIY boxes. Well, maybe not nice looking, but definitely DIY.

5. Band all batteries in groups of 6 with a strapper. The strapping is just for organizational neatness and ease of handling.

dude... you're dissing my polypro welding. ?!

actually, its very easy to work with, although it makes a mess of the garage with the chips having significant 'static cling' to everything. The heat-welding is easy... like caulking, but you really need the tip that lets you feed in the rod of material like a TIG welder to do a decent job. The poly gets a little flexy, and needs at least aluminum 'edges' to keep long spans straight.

the strapping thing is separate, but pretty easy way to make 3,4,5 cell blocks more manageable. The 'ends' may be better with plates to prevent bowing, but maybe not. I am not convinced that tight banding is better... if tightly constrained, than an overcharge event (causing by internal overheating) would be even more likely to vent rather than flex a little, so I don't see any real advantage to tight banding...

 

[dladd]

dude... you're dissing my polypro welding. ?!

No way! I hope my boxes come out as well as yours! thanks for the info on the feeder attachment, I was wondering if that was worth buying with the heat gun.

 

[dexion]

david,

I cant remember the weather where you are at. The reason I had them all in the trunk is to keep them the same temp. I worried about having some up front in 20F weather and some in the trunk at 40F perhaps for no reason. Also its easier to get them above 32F in the trunk for charging (spec sheet says cant charge below freezing.) but yes its bottom heavy.

 

[dtbaker]

No way! I hope my boxes come out as well as yours! thanks for the info on the feeder attachment, I was wondering if that was worth buying with the heat gun.

The rod/feeder nozzle thing is key to directing the heat right to a small area and getting the filler rod pressed in there as you go.

regarding same temps of batteries in separate locations.... thats part of why I wanted to have both front and rear boxes of similar construction and totally enclosed in the winter. because my original build was lead, the boxes are deep enough to put rigid foam in the bottoms, but I decided to leave the side un-insulated and may just put a layer of mylar space blanket in there as it doesn't get very cold where I live and my car is in a 50 degree garage overnight...

 

[dladd]

david,

I cant remember the weather where you are at. The reason I had them all in the trunk is to keep them the same temp. I worried about having some up front in 20F weather and some in the trunk at 40F perhaps for no reason. Also its easier to get them above 32F in the trunk for charging (spec sheet says cant charge below freezing.) but yes its bottom heavy.

Yeah, in the dead of winter we never go below freezing. There will be some temp difference, but I don't think it's too bad. Most of the year is between 50-80 degrees during the day.