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1962 Mercury Comet + 2013 Nissan Leaf

4906 Views 60 Replies 13 Participants Last post by  olegil
I already made a post in the new members introduction section that highlights my previous builds, including an EV classic motorcycle. In that thread I shared that I bought a wrecked 2013 Nissan Leaf.

Wrecked Leafs like this don't come up for sale very often in my area (Kansas, US) so I bought it. The good: it was made in late 2013 so it has the upgrades over the first gen Leafs, and it has the 6kw charger. The bad: it only has the 24kwh battery and it's a 78% health, which means its really a 18kwh battery pack. And the front sub frame is mangled.

I'll buy a Resolve-EV controller as soon as they're in stock again. I've been waiting patiently all month but the website still says "More stock by end of February".

Then I started hunting for a car to put the Leaf parts into. I'm a fan of classic cars, and station wagons in particular. My brain was telling me to use a retro Mercedes 300TD wagon because the chassis and bodies are well contructed, safe, etc. But my heart was telling me to get something more classic, like a wagon version of a Chevy Nova or Plymouth Fury or Ford Fairlane.

Well I couldn't decide, so I bought both!

The yellow wagon is a 1980 Mercedes 300TD. It's running and driving pretty good although needs a little work, but it just completed a drive from Los Angeles to Kansas City so it the engine is strong. I'm not sure what I'm going to do with in the long run, I think I'll keep it for a backup EV conversion candidate.

But here's what I'm really excited about.

This is what I'll be converting. It's a 1962 Mercury Comet. Identical in many ways to a Ford Falcon. It's in great condition, it does have a small, running engine and a three-on-the-tree transmission, but there's no driveshaft currently. I'll need to upgrade the brakes, add seatbelts, give it a paintjob, repair the roof (it's caved in a little), and do a little interior work.

This is a perfect restoration candidate. Ugly but in great condition. All the glass is there and not cracked, including the wrap around rear windows which would be impossible to find I think. All the chrome trim is there and just needs to be polished. The chrome bumpers are perfectly straight. Most of the body is really straight and dent free, only the roof needs repair. And there is not a lot of rust, most of it can be sanded off or treated with POR15.
Vehicle Car Steering part Motor vehicle Fixture

It was last registered in 1975! Lived in California its entire life.

BTW you might be tempted to think that this is a super heavy American gargantu-wagon. But it is a small car, made to compete against the VW Beetle and the Chevy Corvair. The sedan version only weighs 2,600 pounds! I'll try to get this wagon version weighed but it could be around 2,800 pounds.

I want to get it running as-is (with the ICE engine) just to see how it performs, and get it registered. Maybe dress it up like a mini Ghostbusters ectomobile. And then this summer I can start the EV conversion.

Here's the Comet's ICE engine.

Hood Motor vehicle Wood Automotive tire Gas

170ci (2.8L) inline-six. New carb, new fuel pump, new starter, new exhaust manifold, new battery, new alternator (generator?). I had to add a manual choke cable and replace the starter solenoid, and now it runs pretty well. But I think the clutch is stuck and I can't really get the transmission out of neutral I don't think. There's no driveshaft because the the previous owner tried to install an OD unit to the output of the transmission, and it's all hodge-podged together.

I need to decide how I'm going to convert it to EV. At this point, I have a lot of options. [Update, I'm not doing any of these options lol]
  • traditional EV conversion: mount the Leaf motor to the old manual transmission via a coupler and adapter plate. Put the batteries behind the rear seat and add a leaf to the leaf spring pack to handle the extra weight.
    • I can buy the adapter plate but it would be really expensive, or I can make my own using SendCutSend but there's the possibility of errors
    • for the coupler, I really don't understand the concept. Why do some people use carrier bearings?
    • If the trans I have now is no good (possible) then I'll need to find another one.
    • and I would still need to upgrade the brakes and handling ($1000 to $2000).
  • Building/modifying an independent rear suspension (IRS) and mounting the Leaf motor+gearbox to it, with custom CV shafts to the rear wheels. Fill the engine bay with batteries.
    • might save a lot of money and weight, and might not be more work then making adapter plates and couplers
    • the Comet is pretty small, same size as a Falcon or Mustang, so not a lot will fit. Certainly not a Crown Vic subframe.
    • might be able to use a Miata rear subframe, it's the right width, but the Leaf motor may not fit in there, and the Miata suspension will need to be upgraded for the extra weight
      • I could also swap in the front Miata subframe while I'm at it, and get brake and steering upgrades.
    • might be able to use a Benz w123 rear subframe, but will need to modify it to be 2" more narrow and also will have to run the Leaf motor+gearbox in reverse!
      • Someone did this with a w123 subframe and a Tesla motor. I've also seen a tesla subframe get narrowed. So it might be possible.
      • This was my plan when I thought I was going to convert the Mercedes 300TD. And I love how the suspension feels on that vehicle.
      • Running the Leaf motor+gearbox in reverse is possible but if the bearings are unsealed then not advisable.
    • wheel bolt pattern could be an issue
  • convert the Comet to FWD. Similar to the previous idea but will need to find a FWD sub frame.
    • might be able to use a subframe from a Ford Focus or something, but modified to be a few inches narrower.
    • The Leaf's front subframe is too wide, and the one I have is too banged up after the wreck. Could be straightened maybe, IDK.
    • This honestly seems like a better idea than putting the motor in the rear, will be easier to fit.
  • Mount the Leaf motor+gearbox at 90°, such that one CV shaft attaches the the driveshaft, and fix the other CV shaft so that it can't spin. No, wait, this won't work because the rear axle adds more gear reduction.
My goals are to have a daily driver classic car that is also EV, and big enough for the whole family. After the conversion, I'll probably want to upgrade to a 40kwh battery pack if I can find one. Speed is not something that really excites me like it does some people, but if I can do a burnout then that would be cool I guess.

This project is probably going to take a few years. Wish me luck!
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From the description of the linked valve:
A Proportioning Valve has the job of restricting the amount of brake pressure sent to the rear of a brake system under heavy or severe braking. A common ratio or brake bias for a proportioning valve is to distribute 60% pressure to the front brakes and 40% pressure to the rear brakes. As brakes are forcefully applied, the front of the vehicle experiences additional loading as energy is transferred from the rear of the car to the front wheels requiring more front brake bias and less rear brake bias.
This is a bit incomplete. The proportioning valve does not affect the pressure to the front brakes, and it only affects the pressure to the rear after a threshold input pressure is reached. That means that under light braking the front to rear pressure ratio is 1:1, and the ratio of braking effort to the wheels is determined by disk diameters and caliper piston areas. Under harder braking the proportioning valve reduces the pressure to the rear (relative to the front), so the ratio of braking effort to the wheels is still determined by disk diameters and caliper piston areas, multiplied by the reduction ratio.

This description says that above the threshold the pressure distribution is "60% pressure to the front brakes and 40% pressure to the rear brakes", which suggests that pressure being 'split up' in some way, which is physically nonsense. What is really happening is that the ratio of input pressure to output is 1:1 for the front and 1:0.67 for the rear, meaning that the front to rear ratio is 1:0.67 or 60:40 (or 6:4, or 3:2, or whatever two numbers you want to use where the front is 1.5 times the rear). As Wilwood (who actually makes these valves explains:
The name "proportioning valve" seems to confuse people. The valve is more of a pressure regulator, decreasing how much pressure goes through it by a set amount (once initial pressure reaches a certain point). Reducing the force going to one circuit doesn't increase the force going to the other brake circuit. However, when the valve reduces pressure to one circuit, the proportional relationship between the front and rear braking (front to rear brake bias) changes.
Because only the rear pressure is being affected, a proportioning valve is only in the hydraulic path to the rear, and in racing cars it is often mounted beside the driver in the line to the rear so that it can be adjusted by the drive. The only reason that front and rear lines both pass through the combination valves is so that it can incorporate a failure warning switch (which trips when front or rear has pressure and the other does not due to a leak).

Trying to use a proportioning valve to fix bad system design would require two proportioning valves: one would be adjusted to a zero threshold value so it always cut rear pressure, and the other would have the normal function of reducing the rear even more at high input pressure to shift the balance to the front under hard braking. I have no idea if that would work, only that it would be a bad idea.

Adjustable proportioning valves are routinely available; they are used in custom builds and racing vehicles to fine-tune braking behaviour, and should not be used to fix incorrectly sized components (although First Place Auto Parts and even some aftermarket valve manufacturers suggest doing exactly that). Only the triggering threshold pressure is adjustable - the ratio by which rear output pressure is fixed by the design of the device, so it is fundamentally incapable of fixing brake caliper sizing errors.
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Now, how about an essay on the metering valve?
For those who are curious, the Wilwood page also provides an explanation of the internal operation of the metering system used in a proportioning valve, the "How it Works" section. That explains why the input to output pressure ratio can't be adjusted, so it can't be matched to the random combination of braking components (disks and calipers) that may have been assembled. Wilwood doesn't include an internal diagram, so here are the two steps from another source (note the stepped piston, establishing the two piston areas which determine the pressure ratio):

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Finally starting to shift from the just-talking phase and into the doing-stuff phase.

I pulled the axle shafts and front hubs off the Leaf.
Automotive tire Wood Auto part Automotive wheel system Metal

And I was going to pull the rear hubs and rear brakes off, to see if the rear brakes would work with the front hubs as I had hoped they would, but it was quickly pretty obvious that they wouldn't work, and for multiple reasons. The bolt pattern for the hub's mounting bolts was not the same, just a little bit off. So the caliper mounting plate wouldn't fit with the front hubs. But the bigger problem was that the depth of the hubs where completely different, to account for the rear drum e-brake inside the rotor hat.
Automotive tire Leg Motor vehicle Automotive lighting Luggage and bags

In this photo, I holding the front hub up to the rear hub such that the mounting flanged are aligned, and you can see how much longer the rear hubs are. They're a mile off.

So I'll need to think some more about what to do for rear brakes. The EV West guy used Honda Accord brake calipers and rotors, which have the e-brake cable going to the caliper, and he welded simple tabs to the De Dion tube to hold the calipers. So I'll probably just follow his example.

I'll need to have all this sorted out before I begin building the De Dion tube so that I know exactly how wide to make it.

And just to remind everyone what I'm converting...
Wheel Tire Snow Vehicle Car
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Will a machined spacer plate work, with the knowledge you can concentrically rotate that bolt pattern for the mounting?
I see what you're getting at, but... I just can't make it make sense in my head.

The rear rotors are deeper, to account for the drum brakes inside, and this will cause the rotor surface to be more inboard, possibly fouling with the leaf springs even..? Probably not, but there's no way I could use the Leaf's e-brake with the front hubs.

And I really need to have good e-brakes on both wheels sense there is no feature with the Resolve-EV controller to control the parking brake on the Leaf gearbox . (Maybe I could make my own simpler circuit to control the parking brake but I would probably want to have some logic to control it so that its not accidently engaged while driving).

So I'll just stick with Johnny 5's example and use 2005 Honda Accord brakes because they have a cable going to the calipers for the e-brakes. Bolt everything together after I've built the de dion tube, put the calipers on the rotoers so that they're just floating, build tabs to mount the calipers to the de-dion tube structure, bolt them to the calipers and then tack weld them onto the tube, unbolt everything and finish weld them. Super easy. And the Accord rotors have the right bolt pattern too!

Tire Wheel Automotive lighting Automotive tire Vehicle

BTW, the Resolve-EV website nows says it will be in stock on March 25th.
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No progress to report other than I got the car running in its original condition and drove it around the block. The driveshaft was banging against the previous owner's homespun bracket for the e-brake. I think if I can sort that out and get the brake lights working then I can drive it to the inspection office. The original engine needs to be in there so it can qualify as an antique vehicle in my state (KS) which will allow me to get it registered without a title. I've done this process a few times.
Wheel Car Tire Vehicle Land vehicle

I haven't had time to do much else because I've been a little preoccupied with buying a new house and selling our current one. My wife's idea. Say goodbye to my Tool Temple! :(
Property Wheel Picture frame Tire Building

Plant Building Property Window Wood

But it's all for the best. Plus, our new house has a two car garage that should be a little easier to work on the car in.

Also, I'm still waiting for the Resolve-EV controller to be back in stock.
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The Resolve-EV controller is back in stock! I just ordered one.

90% sure I'm going to convert my '62 Mercury Comet, 10% chance I will convert my '80 Mercedes w123 instead. Our family car/daily driver, a 2013 Volvo, overheated and might need a new head gasket, so the 1980 Mercedes has taken over family hauling duties for right now. I'm trying to convince my wife to trade in the Volvo and get an EV or a PHEV.

I also uploaded this to YouTube. I don't think the DIY EV forum is going to care much for getting the old gas-powered engine to run, but it also gives a good, detailed view of the vehicle that I will be converting:

Side note: my video for my EV motorcycle (in my avatar photo) is currently going viral in Japan, Thailand, and Vietnam 8)
I'm getting ready to remove the battery pack from the Leaf. I tried to charge it a few days ago, using the granny charger, but after an hour the SoC percentage had not increased at all. Sitting at 65%, although the display on the dashboard appeared normal. I have never charged an electric car before, so its all new to me, but the dashboard said it was plugged in.

I wonder if an error code in the Nissan VCU (??), a result of the collision, is stopping it from charging. Any ideas?

Anything else I should do before pulling the battery? Other than pull the service disconnect, of course.

Should I release the parking brake on the Leaf gearbox before the battery is pulled out? Can I keep it non-engaged somehow?
I bought a wrecked leaf also with a good battery. It wouldn't charge while still in the leaf. But it charges fine with the Resolve-EV brain.
Also, in another thread you asked if the transmission park function can be used. I have it working and so far no issues. I documented how I did it in this thread:
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Thanks dddrewski. I'm not sure if I'll use it, I just need it disengaged, maybe permanently, and without having to crack open the gear box.

I think what I'll do is turn the car on, put it into drive, and then disconnect the parking actuator.

If that is not good enough then I'll have to deal with it at another time. I have to get this car out of my driveway ASAP. I waited until the 11th hour to start taking the parts out, and now I have only a few days to work on it, why also doing everything else I need to do around the house before we put it on the market. The realestate photographer is coming on Tuesday and no one wants an ugly wrecked car in the driveway.
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Putting the Leaf into drive and then pulling the wire to the parking actuator must have worked to because when I turned the car off, a very angry message appeared telling me to use the emergency brake.

And then I could start pulling parts out. First up was the battery pack.

Wheel Tire Car Vehicle Plant

I built a special cart for this job. There's four large, pneumatic tires, two of them are the swivel type so it can be steered. I couldn't use furniture dollies or anything because of the gravel driveway. The cart is about 10" tall, it needed to be tall enough to be taller than the lowest point of the floor jacks, and short enough to allow enough clearance to pull the battery out from under the car.

To lower the battery onto the car, I used two floor jacks. I first removed all but the 6 large bolts under the door sills. Then I put the two floor jacks under the battery, with enough room for the cart to go in the middle, and then raised the jacks until they were putting upward pressure on the battery back. Next, I removed the last 6 bolts, then lowered the floor jacks, dropping the battery onto the cart. Worked like a charm!

The next challenge was to remove the motor/inverter/pdm stack.

Tire Wheel Vehicle Automotive tire Car

The hoist got stuck in the gravel, I did not properly plan for that. In the back of my mind, I knew this was going to be a problem, but I consciously ignored it until I couldn't any more.

For removing the battery pack (600 pounds), that's where all my thinking-ahead went into. Everything went to plan when it came to removing the battery. But when I got started on the electric motor, I just hadn't done any forward thinking.

Whatever though, it worked out, I conquered. I was able to move the hoist by dropping the engine onto the ground, move the hoist back a foot, lift up the engine, and repeat several times.

Another issue was the refrigerant - it was all still in the car! I thought it would have all leaked out after the crash, but thankfully not and now it can safely be recovered. There's one pound of r134a in there, and that has the greenhouse warming potential of 73 gallons of gasoline! Scary to think about all the millions of cars with their leaking AC systems...

But I don't have the tools to recover it, and I called a mechanic and they would need to have me tow it to them. So I called my residential HVAC contractors, and they wouldn't touch it (its the wrong refrigerant for them).

So right now I thinking about somehow cutting the firewall such that I can remove the heat exchangers inside the cabin, and take the whole closed loop to a mechanic. I'm going to work on that today. Kinda crazy, just might work. When pulling the motor, I had to unbolt the AC compressor and also disconnect the HV wires to it. Maybe I'll be able to use them in the new car...

Also, my controller arrived in the mail from Resolve-EV!

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Come to think of it, would I even be able to re-use the Leaf's compressor? It's a high voltage electric motor, I don't know if in needs a special controller, I don't really know anything about it to be honest.

But today I was able to get the PTC heater, the throttle pedal, the water pump and hoses, the electric fans, the BMS wiring connector and pigtails, the service disconnect... I think thats about it. I'm not going to try to use the Leaf's power brake booster, I've read its not as DIY friendly as the iBooster.
Great work! And all on a gravel driveway! I had to haul my leaf on a trailer to a auto-shop to get the AC evacuated, and not all of shops could handle the stuff that was in it (r134a). As my tractor project doesn't have a cab I haven't thought of anything to do with the AC/heater components. But it does seem like it could have some use. I'm impressed that you could pull the motor/stack out and keep the AC lines in-tact.

When I was bringing up the components to run outside the car, it was fun to be able to push on the brake pedal and see the booster rod move in relation to the pedal (like a phantom limb). I am still using the original leaf VCM/BMS. Which in hindsight has been the biggest challange of the project, but learning a lot in the process. Looks like the resolve controller has enough wires to be a challenge as well.
Great write up. And extra credit for the Cosmo Kramer painting in the shop.
I got the battery pack and the motor safely into my new garage. Once I didn't have to deal with a gravel driveway, everything became 1000x easier. My new driveway is also relatively level, slopping gently away from the house, so pushing cars and hoists around will be a breeze. But it going to be along time before I have everything organized and a work space established.

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You can't even really see the Leaf motor in the above photos, but I promise its in there somewhere, buried in the rubble.

But you can see my EV motorcycle conversion at least. I'm hoping to bring it to the La Vita Volta EV conversion show in Denver CO, August 5th. (sadly I just realized I overbooked that weekend and I also bought tickets for a concert in Kansas City the day before the show...)

I got everything I needed out of the Nissan, I think, and sent it to the scrap yard. I just had to fill out a little paperwork and the recycling center sent a tow truck to get the car. It only had two wheels but it was not much of a problem.

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These are the parts I salvaged from the Nissan:
  • motor, inverter, PDU
  • battery pack
  • HV heater core
  • all the HV wires
  • charge ports
  • throttle pedal
  • CV shafts
  • wheel hubs
  • water pump & hoses
  • BMS wires & connector
  • hmmm, I think thats about it
I made a hair-brained attempt to remove the entire AC system, without cutting it open and leaking anything out, by cutting into the firewall to remove the heat exchanger. But I didn't get very far, and I ended up leaving it all in the car still. The recycling center said they will capture the refrigerant, but she said it with a little bit of a nod and a wink, and I really hope she wasn't lying to me.

Meanwhile, the Mercury Comet that I'm putting all these parts into is still stuck at my old house. I can't get it running. After I was able to drive it around the block, it started running worse, then it stalled, then it wouldn't start. I took the carb off, took the float and jets out and cleaned them with carb cleaner and then blasted everything with compressed air. Put it back on and the car was running OK-ish for a little while, then quickly went bad again. I put in a new, clear fuel filter and it is still clean, but the carb is acting like its really dirty, IDK. There's no vacuum leak, the timing is probably pretty bad but I can't get it running to find out.

Wheel Tire Car Vehicle Window

Sadly, the art-car parade I wanted to enter into is this weekend, so its unlikely I will get it running in time and also get it dressed up as the "ecto mobile" from Ghostbusters. That was my plan, but the big move took priority over everything else up until a few days ago.

Good think I'm converting it to EV and don't have to worry about carburetors and dirty gas tanks.
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Fuel pump diaphragm may have holes/cracks in it.
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Maybe, the clear fuel filter says otherwise, but even if that was it, it's just too late now to try to get it running again. On with the EV conversion!
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