Motor Installation

After 3 long months of waiting the gearbox, couplers and adaptor plates arrived. At first try the coupler did not fit so back to Geoff for some fine tuning. When it came back everything fit ok so I fitted the adaptor plate to the motor then the coupler and after a lot of time sorting out the right bolts and lining up the motor on the hoist I fit the motor to the gearbox and tightened all of the bolts.

Next I lifted the motor gearbox into the car and bolted it to the front and rear transmission mounts. I the refitted the drive shafts to the transaxle and remounted the wheel hubs and steering arms. I then connected the output of the oil pump to the input to bypass the oil cooler in the radiator, as it will no longer be needed. The majority of the heat generated in an auto transmission is from the torque converter and this is now gone. I filled the transmission with atf and I was ready for a test run.

I put the transmission in D and connected the motor to the old starter battery and hey presto the wheels started turning. There was a very short delay between when the motor started turning to when the wheels turned, maybe 1/4 second. I don't know what this will feel like when driving yet but I have some ideas on fixing the problem.

I installed the ceramic heater core in the heater unit and put the dash back in. About another 4 hours work all up. I am still waiting on the coupler and adaptor plate for the motor / gearbox. This was bad timing as I gave it to Geoff to convert just before he went on leave. I should get it back next week if all goes well.

I have been working flat out on a design for the motor controller over the last few weeks. It's an open source design and I am just doing a bit of fine tuning and the final board layouts. Beta testing of the unit is almost complete with no major issues. http://ecomodder.com/forum/showthread.php/paul-sabrinas-cheap-144v-motor-controller-6404-224.html

Its a long read at 224 pages and growing. Paul has done a fantastic job with the design. We are arranging a bulk buy of parts for Aussies, see http://www.aeva.asn.au/forums/forum_posts.asp?TID=1160&PN=1

Dashboard gone
Dashboard removed

Removed heater core

Being a glutton for punishment, I decided that the next thing to do would be to replace the heater core with an electric element, as there will be a severe lack of hot water in the car after the conversion. I sourced a 120 VAC ceramic heating element from a guy in the USA who sells them to EVers in Australia.

The removal of the dashboard took about 4 hours and is possibly the worst part of the whole job. Without the manual I think it would have taken 8 hours. The most dangerous part of the operation was removing the air bag. Apparently they can go off with very little provocation, hmmm very similar to a woman. Next is removal of the steering wheel using a steering wheel puller, $20 from Supercheap Auto. The instrument panel was removed and I noticed that the front panel was cracked. It looks like a trip to the wreckers for a replacement.

While I was disconnecting some of the wiring connectors I noticed a non standard unit wired into the ignition wiring. It turns out it was an aftermarket engine immobiliser and remote keyless entry. The wiring was very poorly done with wires cut and twisted, no connectors and no solder. As I didn't get the remote control when I bought the car I removed the unit and restored the wiring to original. Finally after removing the dash & the aircon unit I got to remove the heater unit. The heater core will have to be modified to allow the mounting of the electric element into the old core frame.

I sold the old engine on Ebay this week. I listed it last week and it sold for $1.50. It turned out the guy who bought it didn't check where the engine was. He was in Adelaide and I am in Brisbane - go figure. Anyway he defaulted, I relisted and sold it for $100 to a local. He also took a lot of the other bits I didn't need, so I won't have to dump them.

The plans have evolved a bit more now. The automatic transmission is now on it's way to Sydney so that Geoff from GT Tooling can make the adaptor plate and coupler. The plan is to remove the torque converter cut it open and use the internal splines to create a coupler. The secret is to recreate the normal transmission fluid path from the centre of the pump shaft back to the outer shaft where it returns to the transmission. He is also going to make a plate for the rear of the motor to mount the air conditioning compressor and power steering pump

The other problem to overcome is that the transmission clutch for 1st gear will not engage if the transmission pump is not operating ie when the car is stopped at lights etc. I am going to do some tests when I get the transmission back to see how long the pressure remains in the box after the motor stops turning. This should be proportional to how good the seals are. Geoff has suggested that an accumulator connected by a solenoid valve could be used to apply pressure instantaneously to the box when the accelarator is pressed. The logic behind this may be a bit hard to apply and it may be restricted by how fast the clutch can operate compared to the motor.

The other option is to use an electric pump operated from a pressure sensor to keep the pressure up to the clutches. The pump would only operate when the pressure drops below the point at which the clutch would disengage. To make this more efficient, the pump could also be turned off if the brakes are applied, so that when you lift your foot off the brake the pump starts and by the time you apply the throttle the clutch has engaged (if it engages fast enough). Either way there is a bit of testing to do before I proceed any further.

I have settled on a controller for the project. I will be building the controller myself from an open source design see link http://www.paulandsabrinasevstuff.com/evmotorcontrollers.html
It is a 144volt 500Amp controller and it meets my requirements for power. Parts have been ordered andshould be delivered within 8 weeks. Construction should take a few more weeks after that.

For batteries I will be using Lithium Iron Phosphate batteries from Thundersky. I am still tossing up between the 90 Ah and the 160 Ah batteries. I was going to try to fit all of the batteries under the rear seat where the fuel tank was but the available space is just too tight to fit all of the 90's in the one spot. Depending on which battery I can afford at the time I will mount some under the rear seat and some in the engine compartment. I calculate that I can probably get about 90 Km range from the 90 Ah batteries and about 160 Km from the bigger batteries.

I am looking at 2 different battery management systems. The 1st is an open source processor controlled shunt device which has over & under voltage protection. The 2nd option is an active powered system where a small power transformer feeds each cell independently and the amount of current to each cell is controlled by the state of charge of the cell. This gives the best balancing but is limited by the size of 45 transformers and the addition wiring to each cell. The main advantage with this system is the simplicity. I will have to get a few batteries and do some testing to see which way works best and is safest.

ICE Removal

Transaxle ready for a cleanup

Anyone want a 1300cc Mazda ICE

Empty engine bay

Out with the ICE

The electric motor (Impulse 9) was delivered last week.

On Saturday I pulled the axles from the transaxle. This was hard going as the axle nuts wouldn't budge even after soaking in rust remover and using a 600mm break bar. In the end I removed the wheel hubs with the axles attached. The manual said to pry the axles out using a pry bar but I found using 2 bars one on either side more effective. I then loosened all of the engine mount nuts and made sure the engine was free of everything holding it in.

Today I removed the engine. I hired an engine crane and it popped out with no problems at all. I had to disconnect the air conditioner condenser because the return pipe was in the way.

I then removed the transaxle from the engine.

Got back into it this afternoon and removed the entire exhaust system, battery, radiator and disconnected most of the engine wiring and the air intake.

It was hard going at first with lots of rusted nuts in hard to reach places. I then decided to take out all of the easy stuff first and the extra room it gave me let me easily undo the difficult nuts and bolts. The auto gearbox has an oil cooler built into the bottom section of the radiator, so I will have to get an aftermarket oil cooler to fit in it's place.

The workshop manual arrived this week and so I started the dismantling phase this afternoon. I was dying to get started early but family duties took precedence in the morning.

I drained the fuel tank by removing the fuel pump and syphoning the petrol out, then removed the fuel tank and all of the fuel lines. Next to go was the fuel filter and the carbon canister. This is really a dangerous operation as petrol keeps spurting out of the lines as you remove each part. I made sure I had a couple of fire extinguishers nearby ready to go and cleaned up each spill as it happened.

The exhaust system is next so I started off by giving each nut a good spray of CRC to try to free up the rust. It worked on the catalytic converter nuts but not the rear join. So tomorrow I will use a grinder to cut those off.

Well here goes nothing

The conversion of a 1998 Mazda 121 automatic hatchback to a plug in electric vehicle has officially started.

I bought the donor vehicle last weekend had it weighed, measured the ground clearance on each wheel and put her up on stands so I can start work removing all of the bad stuff. Engine, fuel tank etc.

I have ordered the workshop manual so I will wait till it arrives before proceeding. It still has a nearly full fuel tank so 1st thing to do is to syphon it out before removing the tank. I have to be carefull here as it would be very embarassing to set the car on fire under my wooden house. It turns out I have to lift the rear seat, remove an inspection plate, remove the fuel pump connector, start the car and wait till the engine stops to release the pressure in the tank. I can then remove the fuel pump from the tank and siphon the fuel out. This is going to have to wait for the weekend. What happened to the good old days when you could just bung a bit of garden hose down the filler pipe, a quick suck, lots of choking and out comes the fuel.

The plan for the car so far is

Netgain Impulse 9 DC motor - on order

45 off Thundersky 90 AH Liffepo4 batteries

everything else is still flexible