E-Miata

Gas Gone and Top's Off

2009-04-26T20:41:00.005-04:00

The final gas related components (well OK - not quite - the ECU is still left - but that's electrical) that needs to come out are the the 2 fuel lines and a vapor line that connected the gas tank to the engine compartment. The 3 lines are held in place by 7 clips or so that also hold in places the brake line going to the rear brakes. I had to remove all the clips, press the 3 lines out of them and then re-attach the brake line to the clips after I was done as there was no enough room to simply remove the fuel lines on their own. The hand-brake cable on the passenger side also had to be unbolted to make it easier to remove the fuel lines (as you can see in this picture, is crosses the fuel lines in the background).

After a bit of twisting and pulling all 3 lines were out.

In addition to converting the car, I'm also planning on a bit of renovation - the exact scope is still to be determined. But the number one priority on the list is to replace the 17-year old roof. It's been years since I was able to zip up the plastic rear window and there are numerous holes in the vinyl fabric. It got to the point where I would check the radar at work and if there was a storm coming, I'd have to take the baby car home before it hit and return in another, more weather resistant car.

I also need to take the roof off to access the back parcel shelf, which covers the space previously occupied by the gas tank. I'd like to use the space back there for some of the batteries, but that is going to require removing some of the sheet metal and having the roof removed is pretty much a necessity to accomplish that (for an example of some MAJOR surgery to make room for batteries, see the link to Andrew Schwarz's conversion.

So off it comes. Now, much as I'm enjoying documenting the details of what I'm doing, I don't see the sense in re-inventing the wheel and there is a terrific post at www.miata.net that gives all the details you could ever want on how to remove and install a roof on an Miata. So if you are tackling a roof replacement see that article or any of the other roof replacement articles in the 'garage' section there.

But to keep Brian happy here are some pictures I took and some notes of differences in procedure that I used. To give credit where is it due, the Miata.net roof article is obviously where where I learned the trick of connecting 2 wrenches to get more leverage - here's me loosening the very tight bolts holding the driver seat.

Note the leaves above ... there are even more sitting under the seats when they come out (the perils of leaving the car sans roof most of the time).

The rear window hasn't zipped for years and getting the push fasteners holding the carpet covering the parcel shelf off was a lot easier with the window gone so I took a utility knife to it. Note the wonderful shade of brown that years of exposure to the sun have left it (no cracks though!).

Here is the rear shelf exposed now the roof has gone ... later we'll see what surgery I'm willing to perform on it (or not). Also note the 2 zip lock bags below, one in each seat position - I made sure store the various pieces removed from each side in the appropriate bag so I know which side to eventually reinstall them in.

The roof covering is not too difficult to remove from the frame (which obviously will get reused) but since I'll be getting a new covering I took some short 'cuts' with the good old utility knife again.

Decisions, decisions, decisions

2009-04-21T20:18:00.000-04:00

I've not really talked much about anything EV specific so far, mainly because I've been concentrating on figuring out how to tear the car apart - I figured that if that didn't go well there was no point in making any decisions about EV components. But with nearly all the ICE components out, the car not looking any worse then you'd expect for one with half it's parts missing and all my body parts still attached it's about time to make some decisions about what direction I'm going in - if I don't I'm sure my better half is eventually going to get a little bored of a hunk of useless metal taking up a garage bay.

Since starting my investigation I've been kicking around 2 possible configurations. The first is a high-voltage AC (alternating current) system consisting of:

- a 320V battery
- an Azure Dynamics AC24LS AC Motor
- the matching Azure Dynamics DMOC455 Controller

or, a DC (direct current) system consisting of

- a 144V battery
- a Netgain WarP9 DC Motor
- a Curtis 1231C-8601 Controller

I liked the high voltage AC option a lot as higher voltage means lower current for the same amount of power, and lower current means better efficiency and hence more range. It also includes 'regenerative braking' (using the motor as a generator to assist when braking, so putting some of the car's kinetic energy back into the battery instead of wasting it as heat from the brakes). But the Azure Dynamics system seems a little anemic when it comes to acceleration from feedback I've found in build logs on the internet.

DC motors are less efficient, and you need to go through a lot of hoops and have a special motor controller to get regenerative braking, but they are far more popular for DIY conversions. Popular opinion is that a DC system is simpler than AC (though as far as I can see, AC systems have more components built in so appear simpler to me!) and there are certainly a lot more examples out there to draw on when I get in trouble/need help so I'm leaning that way.

I was pushed to make a decision this past weekend when I was able to hook up with a group buy for batteries. One think I made my mind up about long ago was what battery technology I wanted to use. Most conversions use good old lead acid batteries - 12-20 or more in series - to create a battery pack of around 144V. But if you've ever changed a battery in your car you'll realize that this is one heck of a lot of weight to add. Even accounting for the 250-300lbs taken out in ICE components, you're talking adding 600-1000lbs to the car - that's going to be a real drag on both acceleration and range.

No - I decided that I would be going with some form of Lithium Ion-based battery. The problem with these batteries is quite simple - cost! There are various battery chemistries and a battery pack can cost between 4 and 10 (or more) times the equivalent nominal capacity in Lead Acid batteries. They also require a sophisticated Battery Management System (BMS) to ensure that the individual cells are not over-charged or over-discharged and remain in proper balance, adding more to the cost.

However they have some huge advantages over Lead Acid batteries. The amount of energy they can store is 2-3 times greater than the equivalent weight in lead, and they are far more efficient in allowing you to extract that energy from them. Also their form factor is much smaller making them (I hope) easier to fit into a small car like the Miata. Lastly, while you can change/discharge the typical lead acid battery 400-600 times before you kill then (depending on how far you discharge them), Lithium Ion (specifically Lithium Iron Phosphate - LiFePO4) cells have up to 2000 or more cycles in them - making them at least as cost effective (though with a higher up front cost) as lead acid as you need to replace then less frequently.

My basic research showed that the typical cost of a 3.2V LiFePO4 cell was about $1.60 retail per Ah (Amp Hour - basically the measure of capacity of a cell - 1Ah means that the cell can discharge at 1Amp for one hour before it runs out). So for a 144V battery made up of 3.2V 160Ah cells I was looking at c. $11,500 before thinking about delivery, duties (these ALL come from China at those prices and a BMS) - ouch! However as luck would have it, I was able to hook up with a group buy of cells that was being put together by someone that reduced to price to a much more palatable $1.10/Ah - or just over $8000 for the battery itself.

That battery should give me a range of about 75 miles or so. That assumes that on average I'll use 250Wh per mile which seems typical. The total capacity of that battery is 144V (45 * 3.2V) * 160Ah, or 23KWh. The battery specs say that they can be discharged 80%, making 18.4KWh available - hence the c. 75 mile range. I might get a little more or a little less, but as my commute is only 4 miles one-way and the longest trip I typically take in the baby car is to RFK Stadium and back for a D.C. United soccer game - about 60 miles round trip, that's plenty enough for me. So I plunked down my 50% deposit with Dave and James from EV Components today for the battery which should arrive in about 12 weeks.

So I've thrown my hat into the DC pot ... now I have to figure out all the other bits and pieces I need to order.

Subframe and Gas Tank Out

2009-04-19T20:04:00.000-04:00

Back from the excitement of my ride in the Tesla Roadster I was raring to get the last vestiges of the baby car's gas legacy out. To continue removing the rear subframe I needed to disconnect the hand-brake cable from both rear brakes - this is a lot easier with the wheels off. The hand-brake cable is the lower of the 2 lines in this picture.

Here you can see the nuts holding it on the driver's side loosened - then it's a case of a little twisting and turning of the cable end to get it released.

Now to disconnect the lower arm of the suspension from the shock absorber. There is a single bolt that the Haynes manual says to "hold with a socket while you loosen the nut" ... well that's rubbish ... you can't access the nut at the other end ... and if your could I doubt you can turn it. Simply loosen the bolt and remove it (I did need to pry up on the bottom of the shock to take some weight to get the bolt out).

Now for the fun bit. First I put my jack back under the differential and jacked it up just enough to start taking it's weight (not enough to raise the car body off the jack stands). The rear subframe is held to the chassis by 2 nuts (fornt and back) and 1 bolt (middle) as you can see in this picture.

Now time to use my newest tool - a Craftsman Impact Wrench. As recommended in the Miata.net article on doing this I used a 19mm deep impact socket and a 6" extension and the nuts/bolts were gone in no time - if you do this yourself get an impact wrench - it's not an option! I started lowering the jack but found the subframe was hung up somewhere ... ah, ha ... I had released the cable loom from the torque bar before I removed the splash guard in the wheel well so I missed the cable tie connecting it to the subframe here

And this bracket which presses into a hole here - you can get that out by squeezing the little clips on the backside just like the wire loom connections to the torque arm.

My next door neighbor, Paul, helped me lower the subframe to the ground (we had to manually lift it off the jack).

Then I dragged it out, jacked it back up and attached the wheels so I could move it around easily.

On to the gas tank finally. First the 4 screws holding the filler in place come out.

The inside the trunk the cover protecting the filler and vent pipes need to come of by removing 4 bolts.

Then you loosen the pipe clamps closest to the tank.

And work the rubber lines off (they come of quite easily).

Under the car there is a plastic cover described in the Haynes manual as the 'Tank protector'. Well it's named wrongly ... it actually protects what I think is the gas filter.

Now I needed to disconnect the connections on top of the tank. To do that the carpet covering the rear parcel shelf needs to come off. It's held in place by 5 plastic push-in connectors. I used a V-shaped pry tool with a screwdriver handle underneath to increase leverage. For some reason the 2 connectors behind the driver's seat were broken before I got to them :(.

Lifting back the carpet and padding exposes the tank access cover which releases with 6 screws.

And here is the top of the tank. The electrical connector to the fuel pump and the 3 lines (2 fuel and 1 vapor return?) need to be removed (I broke the plastic tube connecting the 3rd one by pulling too hard :( ). See all that material on top of that tank? I though initially that was some insulation ... but the I got to thinking why would anyone put some loose insulation there? When when I pulled it out I realized that it was a rodent's nest! Apparently a mouse had worked its way into the space above the tank and built a nest - glad I found that before I pulled the tank and had the 'contents' fall in my face!

I propped up the tank with the jack and a 'few' supports. Yes that is not very stable! But I was able to slowly lower the tank after removing the 4 bolts holding it in place using a plastic bucket and a staging area before removing the wood.

And the gas tank is out. I drained a gallon of gas out of it, and it feels like there is a gallon left - I'll get that out when I have another container to put it in.

I didn't quite manage to get all the gas components out - I'll get to that later in the week.

EV Inspiration

2009-04-19T15:57:00.000-04:00

After I finished work on the car yesterday I took our dog to the local dog park. As I entered the parkway by our house I noticed one of those 'board twirlers' - you know, the guys standing at street corners advertising some furniture sale, or apartment complex or, as in this case, new subdivision trying to sell $1.5M houses in our wonderful economy. Well normally I ignore them, but the light was red and for some reason, while stopped I look over at this one ... and my chin hit my chest ... the new subdivision behind ours was offering test rides in an Tesla Roadster for anyone who visited their model home.

It was too late yesterday (and I had the dog in the car) so this morning I popped over as soon as they opened and YES, they were doing it again today! Sitting out in front of the model house was a red roadster.

I signed up for the hourly raffle for one of 4 test rides and had a look around the house - very nice it was too - but out of my price range thank-you (a bit like the Tesla too I guess). I also chatted to the Tesla sales rep for a while and to the Camberly Homes sales folks and let them know what I was doing with the Miata - that drew a bit of interest. Lucky too, because although my name was not one of the 4 out of the hat, I got a test ride anyway!

And what a blast - even though I was only a passenger, I can now appreciate what an EV Grin feels like. The acceleration of the Tesla is phenomenal - I was literally pressed back into my seat as the driver showed off it's paces.

So a big thank-you to the folks at Camberly Homes' 'Reserve at Stone Hill' development - you definitely made my day today!

An Exhausting Day

2009-04-18T21:51:00.000-04:00

Today was set to be a busy one ... but mostly not because of the car. I started out at 5:20am, getting up and packing the car with soccer equipment to drop off for the first day of the season - I'm the coordinator for the youngest age groups at our local youth club Chantilly Youth Association - about 700 of the c. 2300 players in the soccer program. Then back home and out again at 7:15am to take my oldest daughter to the "Solo & Ensemble Festival" for her flute recital. Next back home to pick up the youngest and take her to breakfast at IHOP for her birthday (she's 11 today) and from there to her volleyball game (also part of Chantilly Youth Association) - her team won their match 3 games to 0 :). That done, back home to cut the grass and kill a few weeds ... whew ... finally time to get something done on the car.

The last remnants of 'gasness' remaining are the exhaust system and the fuel system. The catalytic convertor, exhaust pipe and muffler are hung from brackets using rubber hangers that are easily pried off with a screwdriver (or if you're not going to be reusing them like me, cut with a utility knife). That leaves the cat lying on the ground.

But the muffler and exhaust pipe are hung up on a brace that connects the 2 sides of the rear subframe. I guess if I disconnected the cat from the exhaust it would be possible to pull the pipe out over that bar, but no way is that happening with the cat still attached (and you'll remember how impossible getting the bolts off the cat was when I was trying to disconnect the down pipe when taking the motor out).

So that bar is coming out ... note to self ... just because something looks like a nut doesn't mean it turns like nut. If you look at the connection you'll see a bolt that goes from the underside through the bar and is capped by a nut on top. I spent about 20 minutes trying to loosen that nut before I looked closely and found it was welded to the subframe! Loosening the bolt was a lot easier! With that done, the exhaust system was out (note that was after I had completed the tasks below - I had to 'think' a bit about why that nut was not moving).

So now on to the fuel system. The fuel tank in the Miata sits in a cavity between the trunk and the passenger compartment. Very safe I'm sure, but not very convenient to remove. The only way to do it is to drop the entire rear subframe to make room for the tank to drop down and be removed. I've seen a couple of Miata conversions that decided the effort was not worth it and simply drained the tank, capped the lines and left it there. However I want that space for batteries so it's coming out. Luckily I found a good article at Miata.net that gives a great procedure for removing the tank.

Unlike the factory procedure, this one leaves the torque arm attached to the differential. This means that the wiring conduit clipped along it's length needs to be disconnected - squeezing the plastic clips on the drivers' side with some needle-nose pliers and pushing them through does the trick.

Next the ground wire connected to the torque arm at the rear gets disconnected.

Now the rear brake lines need to be disconnected. There is a single line going into a block on the passenger side just in front of the subframe assembly.

Here's another view from in front of the rear tire - the flare nut looks a lot easier to get to from here.

So off comes the splash guard to give me some room.

Then the brake lines comes off and the brake fluid starts dripping. And dripping and dripping ... essentially you're draining your brake fluid reservoir so it takes a while. So while I was waiting, back to the front of the car to see what I can work on there. Ah, ha, the charcoal canister and electrical connections for the emissions control system are still there.

So off they come.

Back under the car waiting for the incessant dripping to stop, I noticed that there were a couple of heat shields - one between the muffler and the trunk.

And one between the cat and the underside of the driver's seat (what ... no seat warmers!).

So they both come off.

That's it for today - time for a trip to the dog park with the pup, then birthday cake and finally Spike TV is showing the first Star Wars trilogy - so I'm off to watch that (yes, I'm a geek :) )

So long, farewell ...

2009-04-14T17:52:00.000-04:00

There's no turning back now ... the engine was picked up this afternoon. We had a fun time getting it into the back of the SUV that the guy who picked it up arrived in. Strangely enough I knew him - his daughter played on a travel soccer team that practiced at the same time as mine for a few years. He lives very close by so I guess I now have a knowleable resource close by to lean on if (I mean when :) ) I get in trouble (just kidding Greg!).

We had to man-handle the engine in as the hoist obviously couldn't fit into the back of the SUV. I was 'fortunate' enough to discover the remaining coolant in the engine block when we tilted it and it flooded out one of the open hoses and down my pants :(. Here's the engine tied down in the back of the SUV.

It's going to be rebuilt and then raced by Meathead Racing - here's their website: http://www.meatheadracing.com.

Gas leak

2009-04-12T15:42:00.000-04:00

At lunchtime my daughter comes in from the garage to tell me that there is a stong smell of gas so I go out and find a large puddle under the car (needless to say I did not bother to take some flash pictures of the spillage). After removing the engine, I had capped the gas lines with duct tape ... but then I closed the gas cap. Bad idea! As things heated up the next morning the air in the gas tank expanded and pushed the gas in the lines out past the duct tape :(

So now the car is sitting with the gas cap loose to prevent pressure build up in the tank and the gas lines are capped with silicon sealant "just in case". Fortunately it's meant to be cool all week ... but it looks like I'll definitely be pulling the gas tank next weekend.

ICE is out

2009-04-12T00:26:00.000-04:00

By my reckonning the are exactly 4 physical connections still holding the engine/transmission to the chassis:

- the wiring to the starter motor
- the 2 motor mounts, one on each side of the engine
- the blasted exhaust!

Having failed twice to disconnect the latter I decided that it was now time to approached it 'the other way' I mentioned in the previous post. A quick visit to the hardware store resulted in the acquisition of a reciprocating saw and 30 seconds later the downpipe was 'disconnected' just ahead of the cat :)

One down, three to go. The nut connecting the power to the starter motor is pretty inaccessible from either above or below ... but I can get a pair of wire cutters into the space at the rear of the engine ... and then there were two.

But before I forget, this is probably a good time to connect up some chains to the engine and take some of the weight off the motor mounts with the engine hoist. The car needs to come off the jack stands at this point too.

I returned to conventional means to get the motor mounts out - I'll probably reuse them anyway as part of the mount for the electric motor. First thing to do was to loosen (not remove!) the 3 bolts holding the mount to the engine on the driver's side (for reasons you'll see below). One of them is quite inaccessible, being behind the exhaust header but I managed to get a wrench in there.

The other two were easy enough, but there was a bracket still attached to the side of the engine compartment that looked like a knuckle buster. This seemed like a perfect chance to let my helper (going on 11 year old daughter) have a turn with the wrench to break the tedium of a lot of flashlight holding.

Now off come the bolts, one on each side, holding the motor mounts to the chassis.

I lifted the engine just a little more so that the hoist was taking all the weight and then removed the driver side motor mount altogether.

That allowed me to twist the engine and transmission to that side and release the back of the transmission from the torque arm where it had been resting. Now the engine was completely free of everything ... so why when I pull it forward does it not want to come out? Ah, ha! The cable bundle going back down the transmission tunnel goes on the 'wrong' side of the clutch line I left in place. Sorry for the fuzzy picture ... but a quick snip of the plastic wire tie holding the bundle to the engine allowed me to slip it over the clutch line and the engine was now really free.

Rather than just going with a chain to hoist the engine out, I invested in an engine leveler and it was well worth the additional $. If I had another person to help I'm sure it would have been possible to tilt the entire engine/transmission assembly enough to get it out ... but the leveler made doing so on my own a cinch. Here's the engine halfway out - you can see how far it needs to be tilted.

And a couple of minutes later ... the ICE is no more!

Here's another view.

And look at all the empty space (there is still some stuff to come out on the passenger side when the fuel system is removed).

I was tempted to call it a day at that, but I'd like to get the engine out of my garage and into it's new owner's hands quickly so time for a bit more disassembly. With the engine and transmission still in the air, off comes the starter motor.

Here you can see the flywheel teeth the starter motor turns to start the engine.

Now, off comes the clutch release cylinder - much easier to do when it's outside the car.

It is incredibly oily on the outside - I suspect a slow oil leak (especially since for the past couple of years there have been drips collecting under that car!).

Before I lowered the engine and transmission I removed some of the bolts that hold them together (the lowest ones that would be difficult to get to with the combined unit on the ground).

Then the final 2 bolts came out.

And with a bit of prying and a little lift from the hoist, the engine and transmission are separate.

Sheesh, there's a LOT of crud inside the bell housing ... more signs of that oil leak.

I need to get the flywheel off as that will be used during the conversion to connect the electric motor to the transmission using a clutch (you can apparently do this without a clutch ... but that's not for me!). So off comes the clutch pressure plate and clutch disk (underneath it - not shown). I will NOT be reusing the clutch - as with most engine/transmission maintenance - if you've gone to the trouble to remove either or both now is the time to replace the clutch. This one also has 78,500 miles on it ... it's the original.

That exposes the flywheel. Note the channel lock pliers I tried to use to hold the flywheel in place when removing the bolts holding the clutch in place ... I do NOT recommend you do that. The metal the flywheel is made of appears to be very soft - the pliers left deep gouges. I'm not worried about that myself as I plan on having this flywheel lightened and part of that will be to remove the ring of teeth used for the starter motor ... which obviously I won't need any more.

So that's it. Engine is out and ready to be picked up. Looks like I've got a lot of cleaning up to do on that transmission though.

Next up ... well I'm taking a break for the week. Next weekend I'll probably tackle removing the fuel system and clear that last vestiges of ICE from the car.

So much to disconnect

2009-04-11T23:29:00.000-04:00

This is going to be a long one, so I'll split today's entry into two. There are fewer and fewer connections between the engine/transmission and the chassis and I was determined to sever them all today one way or "another" (more on that to follow). First up was to disconnect the transmission.

The speedometer cable connects into the side of the transmission and is easily removed (in fact I think I could have removed it with my fingers).

There are a couple of electrical connectors for the reverse and (apparently) neutral switches (I have no idea what purpose the latter serves - but maybe I can make use of it later). Although both are on top of the transmission (sheesh - who thought of that?) the neutral switch connection was easy to see. I marked one of the pair of connectors so I could match them up correctly later and disconnected them.

The reverse one was impossible to see without a mirror and I wasn't able to mark them - I hope I can get them back together properly later.

There was also a bracket holding the cable bundle going to the back of the car bolted to the passenger side of the transmission so I unscrewed that.

Then I removed the 3 bolts connecting the transmission to the the 'torque arm' (a brace running from the back of the transmission and the differential). The Haynes manual says to remove the torque arm (and I'll need to later) but for now there's no need. You can see the speedo cable hanging loose in this picture too.

And the bolts go in a marked bag for reinstallation later.

Since the transmission is coming out, the shifter needs to me removed and that means that the center console is coming out. First the shift knob and ashtray (what's an ash tray for anyway?) come out.

The screw under the ashtray and two screws under the armrest come out.

As do two screws on either side of the console at the front.

And with that the center console is out. The wires underneath are for the parking brake so I marked them. Then I removed the insulation material round the shift knob exposing the lower shift boot which is held in place by 4 bolts.

Hmmmm - appears I be replacing that - after 17 years of gear changes it's pretty much shot.

The shifter itself is held in by 3 bolts (note in the picture I've reinstalled the 4 bolts for the shift boot - that way I have fewer bags of loose connectors to find when I come to put things back together again).

Once out, you can see the lubricant in the turret. I covered that with some duct tape to stop it spilling out when the transmission is tilted to get it out.

Here's the shifter removed and the (pieces) of the boot.

Now back into the engine compartment to disconnect the remaining connections accessible there. There is a tube going from the near the air intake to the EVAP canister (also known as the charcoal canister ... I guess because it contains charcoal) used to reclaim emissions from evaporating fuel. Too hard to pull off (and I didn't want to risk breaking/bending the nozzle on the engine) so I simply cut it.

I cut the fuel lines too and capped them (both ends) with some duct tape to prevent fumes.

The brakes in the Miata use a vacuum assist to reduce the amount of pedal force required to apply the brakes. This vacuum is provided by the engine and there is a hose going to the brake assist, so off it comes. This is another system I'll have to come up with a replacement for.

The Haynes manual suggest removing the clutch release cylinder which is attached to both the engine and transmission when pulling either. However when I looked at it I realized that it was far easier to leave it in place for now and simply disconnect the clutch fluid line at the top of the firewall when it connects to a flexible hose going down to the cylinder.

As you can see it below leaked a bit of clutch fluid. In fact it kept dripping and dripping until I realized that it was draining the clutch fluid reservoir. So I put a container under it and pumped the clutch pedal a few times until the draining stopped, then bagged both ends.

Whew ... that was a bit ... time for a lunch break.

More connections broken

2009-04-10T10:16:00.000-04:00

After a break for Passover I found a couple of hours to continue with the preparations for pulling the engine. First up were the hoses carrying the coolant from the engine to the heater core in the passenger compartment and then back.

In a gas car nearly 80% of the energy produced by burning the gas goes into creating heat (and noise) and not into moving the car - at least you get warm toes for free :). With no ICE (Internal combustion engine ... not the cold stuff :)) to provide heat, I'm going to have to do something else when the car is converted since at a minimum I need to be able to defog the windshield and, since I drive top-down all year round, a bit of heat to my toes IS quite nice.

While I would have liked to do everything by the book, since there are quite a few items not going back into service in the car I'm willing to take a few shortcuts ... literally. The heater hoses refused to come loose by normal means so, in the interests of expediency out came a saw and, ooops, the hoses are now disconnected.

While I was there, time to remove the ground wire connecting the engine to the chassis.

At the front of the engine, there are some wiring harnesses which I assume connect sensors back to the car's ECU.

So they get disconnected.

Along the back of the engine, more wiring harnesses for the ignition system and other sensors.

They are now gone.

That was all reasonably successful and quick so time to tackle the connection to the exhaust system again. The advice I had received from the person buying the engine from me was to disconnect the downpipe at the catalytic converter and pull it with the engine as one piece. Simple enough, eh? Well not so fast. After 17 years exposed to the elements under the car (moisture from road spray and lots of heat) I was amazed at how little corrosion there was on the exhaust system. Well apart from the nuts connecting the cat to the down pipe :(.

The leverage I could get with my 14mm wrench would not budge either nut. One trick I had picked up from reading conversion blogs (I can't remember where or I'd give credit) was to link 2 wrenches together to get more leverage.

That allowed me to loosen the nut on the driver's side a couple of turns but it seized up again and would not budge and for the life of me I still couldn't move the other one. Time to think again.

Thinking I might have a similar problem removing the driveshaft where it connected to the differential I thought I'd better find that out sooner than later so I headed to the other end of the car. Much to my surprise the 4 bolts back there came off with no trouble.

Time for a break for the evening.

Frustrated by the exhaust

2009-04-07T19:42:00.000-04:00

I'm not too far away from having everything I need to be disconnected before I can pull the engine. Next up was to disconnect it from the exhaust system.

First up, remove the heat shield over the exhaust header. Here is it before:

And the header is now visible:

The Haynes manual suggested that the O2 sensor at the bottom of the exhaust header might be tricky to remove when cold, but it came out easily - here it is hanging out of the hole it screws into.

Now to disconnect the header from the downpipe leading to the catalytic converter. Whoa ... not so fast. As you can see in this picture the connection is held in place by 3 bolts ... but the heads are on the underside of the joint.

After an hour of trying to access those bolts both from above and below I decided I needed to seek some advice. A quick e-mail to the guy who is buying the engine from me confirmed that even someone experienced with pulling Miata engines does not do it this way. Instead the trick is to disconnect the downpipe from the cat and then pull it with the header and engine. It's apparently a bit tricky to squeeze it past the transmission if you are pulling just the engine, but as I am taking both out at the same time that should not be an issue. It's too late to start back on that tonight ... so I'll give it a go tomorrow.

More ICE components out

2009-04-06T20:25:00.000-04:00

Well I never did figure out where that drain for the engine block was so I just went ahead and removed the radiator inlet and outlet hoses - that released a cup or so of fluid that was still in the hoses.

Then the radiator came out by removing the 2 bolts top left and right - another couple of cups of coolant were still sitting in the radiator and that came out as I tilted the radiator towards the lower hose connector as I pulled it put. I also removed the coolant overflow tank - which was seriously lacking in contents - well below the Min level ... well I guess I won't need to worry about that any more :).

Next up the hood came off - should have got a picture of that as my 10 (nearly 11) year old daughter helped with that, steadying one side of the hood while I unbolted the other.

Last up for the evening (more 'daddy' stuff to attend to) was removing the A/C compressor. That involved disconnecting the electric cable which I assume carries the signal for the compressor's clutch to engage. I tried to disconnect it at the compressor (the blue connector on the picture below) before I realized it needed to disconnect it at the connector by the driver side headlight (I labeled those connections to I can match them up when the compressor goes back in).

Then I disconnected the freon lines (Midas did their job - no freon in there - you can see them loose in the picture above) and 4 bolts later the compressor was out.

I need to remember to put some plastic wrap over the freon lines to stop dirt getting in them. Ditto the holes in the compressor that they connect to.

Stuff starts to come out

2009-04-05T16:30:00.000-04:00

Last night was not actually the last drive - in order to heat up the engine and transmission oil for draining I took a 10 minute spin this morning to warm the engine up. Since the gas gauge was now well below 'E' I brought along the gas can I use for my lawn mower 'just in case' - it was not needed.

I got the car up on jack stands and quickly realized that I need to go buy a better floor jack. While I can now crawl underneath it's still a pretty tight squeeze (the jack I got off Craigslist only lifts just over 14"). I made do with it today though.

Next problem was, of all things, draining the engine oil. I'm convinced that the shop I use must have used an impact wrench to tighten the oil drain plug. I could not get it to budge until, in desperation, I slid myself completely under the car, head under the diff, put my foot on the wrench and used that as leverage to loosen the plug. Luckily the transmission drain plug came off a lot easier.

Next up was the air intake system which was easy enough. The belts, however, gave me a bit of a problem until I realised that someone has installed the top bolt on the alternator (which rides in a slot to allow tightening of the belts) backwards (so that the head was to the rear of the car instead of the front). Having figured that out, the alternator came out too.

Next up were the water pump and drive pulleys, but I managed to skin my knuckles badly on the former (at the top of the engine) that I thought I'd give myself some more room before tackling the latter by removing the radiator and fans. So off came the splash shield under the engine and the fans (of the 8 screws holding the 2 fans in, the bottom left one is a real pain to get out). I then opened up the radiator drain plug and out came just over a gallon of coolant. That seems a little light and the Haynes manual says there should be a drain plug on the side of the engine block to drain fluid from it ... but I'll be damned if I can see it.

Oh well - time to stop for the day ... my wife left this morning on a road trip with my middle daughter to visit some colleges (it's spring break here in Fairfax County) so I have some 'daddy' duties to perform with my youngest. I'll get back to it tomorrow evening.

Just for the record, here's what I've removed so far:

- the engine and transmission oil
- the coolant (well some? of it)
- air intake system
- drive belts
- water pump pulley
- alternator
- engine splash shield
- radiator fans

The final drive

2009-04-05T02:15:00.000-04:00

So of course the weather was terrible Thursday and Friday and I had no chance to drive off that gas commuting to work, but today everything brightened up. After the first real grass cutting of the year, installing a couple of new shelves in the garage, andtidying up said garage so I have room to work) I took the baby car on it's last drive as a gas car. I headed off to RFK stadium in Washington D.C. to watch D.C. United get their first win of the MLS season. Driving back I was a bit worried about the needle hovering over the 'E' on the gas gauge, but I made it home.

So tomorrow I begin in earnest to remove all the ICE components.

Freon out

2009-04-01T01:00:00.000-04:00

I had been calling around a number of shops looking for someone to drain the R12 refrigerant from my A/C prior to removing the engine. Very few were even interested in touching it. My regular shop said they'd do it ... but for $50 over their regular A/C maintenance package - sheesh!

I called the Midas shop next door and they said they would do it for their regular fee, so at lunchtime I brought the car in and I got a bit of good news - they only charged me half ... I guess because they only did half the work. So another $45 'saved'. Guess where I'll be going when I need to recharge the A/C?

Now I need a couple of days good weather so I can drive off the remaining 1/4 tank of gas (the roof leaks so I can't drive on the rain at the moment).

Gotta love Craigslist

2009-03-30T18:51:00.000-04:00

So having bitten the bullet yesterday and listed the engine for sale on craigslist I was fully expecting to be waiting weeks to get a nibble - sheesh ... was I wrong! By the time I checked e-mail this morning I had four people looking to buy the engine at the price I listed ... no haggling. Of the 3 I talked to all were interested in the engine to rebuild to put into a racing Miata, so it's nice to know that it's going to have a useful (if possibly short) life after I pull it from the 'baby' car.

Luckily I have been doing some preplanning for this eventuality - and again craigslist was my savior. After weeks of daily searching I managed to find an engine hoist and stand for sale and pick them up about 4 weeks ago. A week later I found someone selling a floor jack. I guess the second-hand market is alive and kicking in the current economic times. So I've been able to more than offset those purchases with what I'll get for the engine ... this is probably the last time I get to be ahead of the game.

So I'm all set to pull the engine which I plan on doing this coming weekend. There are a couple of preparatory items I need to do before that happens. First of all I need to figure out the weight of the car as it stands now and also the ride height so I can restore the balance when I'm done (or ar least know how I've changed it) and restore the same ride height. The latter is easy to measure (though instead of the usual ground to wheel arch measurement, I've measured center of wheel to wheel arch - that way I don't need to worry about different tire pressures). Here's what I got:

- LF 13 7/8"
- RF 13 3/4"
- LR 14 5/8"
- RR 15"

Weighing a 2300lb car is another matter. Others have gone to their local trash depots or weigh stations to do that. Unfortunately our local transfer station can only weight the car as a whole and I really want to know the front/rear and left/right split. So the solution I came up with was to use a 2x6 board about 3' long and a couple of identical 400lb max bathrom scales. I jacked the car up one corner at a time, slid the scales and board under the wheel and lowered the car. Adding the weights of both scales together and subtracting the weight of the board gives me the weight at all 4 corners of the car.

Here's what I got:

- LF 587lb
- RF 632lb
- LR 578lb
- RR 541lb

So total weight (with about 1/4 tank of gas) is 2338lb split 52/48 F/R and 49/51 L/R.

One more thing to do ... tomorrow I'm off to the local Midas to have them drain the refrigerant from the A/C system - a 1992 Miata has an R12 system that would be very bad to release into the atmosphere.

Time to fish or cut bait ...

2009-03-29T21:21:00.000-04:00

For a considerable number of months I've been researching the idea on converting my 1992 Mazda Miata to electric power ... too many months in fact ... I've finally decided to put my money (probably a lot of it) where my mouth is and actually make a start. Today I put an ad on Craigslist to try to sell the car's ICE (internal combustion engine) to give myself a kick-start. I'll give it a couple of weeks to see of someone bites (there must be someone out there both a poor Miata that is sitting waiting for a new engine) - if not ... well the engine comes out anyway.

So why do I want to do this? Good question! I'm certainly not the most mechanical (or electrical!) minded person - for the most part I leave even the basic work on my cars to the 'experts' - so it's not because I'm a gear-head looking for another project to dive into. While I can change a tire and change the odd broken part (for example I just replaced one of the headlight motors - early Miata's have great retro retractable headlights) this is going to be as much about me learning a lot of basic auto-mechanics as anything.

And if I'm honest with myself, there is really no eco-mindedness behind the idea of converting this car from gas to electric. While the idea of reducing my personal carbon footprint sounds nice, it's certainly, in my mind, a bit idealistic to think that converting a single car that is, to be honest, not the most practical of cars is going to make a difference. It's not like I'm going to be driving 1000's of miles without gas - in 17 years I've run up but 78,500 miles - basically it gets used (in good weather) for a 4 mile commute to work and for the odd errand/fun drive when I don't have the kids in tow.

More realistically, I think of this project as a bit of an escape from the daily grind and a replacement for my previous escape route. For the past 10 years I've filled my spare time with volunteer work as a soccer coach and administrator for my local youth club in Chantilly, VA. My kids no longer play and after a couple of years coaching "other people's kids" I was finding that my enthusiasm was beginning to wane so hung up my whistle (BTW, I never, ever used a whistle in my 10 years of coaching!). I'm still the administrator for the Bantam Soccer league, but I really need to find something to fill the hole that weekday soccer practices and weekend games and tournaments has left.

Also, being completely realistic, at nearly 17 years old the 'baby' car (so named by my oldest daughter when she accompanied me to buy it in May 1992 - she was 18 months old at the time - OK, she didn't name it that exactly then) is no longer a baby (neither is my oldest daughter - she's off to college in the Fall). While I've been lucky in having no major mechanical problems, she's had her share of accidents (none my fault) and there are some 'cosmetic' issues that need to be addressed (more on those later).

If I was being sensible I'd say it was time to say goodbye, do the minimum amount of work to fix her up and sell her ... but after 17 years you become more than a little attached to a car like the Miata. So while I thought about replacing her with a new Miata, after careful consideration I decided that I wanted to fix her up. Having come to that decision and already having started researching EV's on the web it was not a huge leap to decide to convert the Miata to electric power while doing some restoration work in the process.

Anyway, that's my way of rationalizing the irrational. I'll keep this blog updated throughout the process in the vain hope that maybe it'll prove useful (even inspirational, as some of the blogs I'll link to from here provided me with inspiration) to anyone else planning such project. I have no idea how long this is going to take, as I have not yet decided exactly on how much restoration I'm going to do ... I guess we'll see as I go along. If anyone actually takes the time to read the blog, I'm sure you know more than I do so your input would be most appreciated.

Here are a few pictures of the 'baby' car I took today to remind me where I started.