WEEK 9: Engine Swap finished ready for WOF and pickup, battery design module cut out, thermistors and LCD's

This week I pretty much finished the entire engine swap and figured out the rest of the wiring to get the car operating as normal.

I wired the power steering back in as well as the cooling fan in the side and then soldered in the ignition jumpers I made earlier in properly.

I then got the car tided up and gave it a good wash so it is now ready for a WOF and pickup maybe next weekend!

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After taking it in for a WOF on Tuesday morning of week 10, it is now ready to drive on the road and roll once again!





I also milled out my battery module design out of plywood and it turned out great, I want to implement a temperature sensor in each one as well.

And I cut out test flanges for the stator motor mounts out of plywood. I plan for these to be made properly out of either thick aluminium or steel.

WEEK 8: Ignition success! Plywood test rotor end cap, Battery Design

On the weekend of week 8, I spent the whole of Saturday (again) trying to figure out the wiring for the igniter. I looked up the wiring diagrams in the online service manuals and watched a couple videos to trace them all back.

I managed to trace all the 5 wires to the igniter and found several things that might be causing the issue. The 3rd pin 12V supply had no pin connector power source, which meant the igniter could not operate at all. The wiring under the fuse box had 3 or 4 wires difference, which need to be copied of the layout of mine, and possibly the ECU signal wires were not going.

After hooking up a couple jumper wires and ground connection to how I thought the wiring should go, I then gave the engine a crank, which after a second or so it backfired which it hadn't done before. This gave me a lot of hope as I figured their couldn't be any ignition without some sort of spark, especially when the engine is cold. I cranked it several more times and kept getting a kick back or bang every so often, which I knew must be close to the problem, the RPM tachometer was also going all over the place and managed to throw itself off, which will need to be calibrated.

Anyway, the next morning, I then had another go at cranking it over with the same occasional backfires. After doing lots of research and having a chat to the guy who I was doing the engine swap for, I kept working at the wiring, which I then managed to trace the signal wires back to the ECU, which was good.

I then tested continuity of all my ground connections which I found that the igniter was now not grounded properly, so I hooked up a ground lead to it, cranked the engine over and bang it fired up to several thousand RPM's as noisy as a plane with no muffler on it.
This was truly amazing hearing all my work going to plan and now I needed to get the rest of the car back together.

On Sunday, I then got the muffler sealed and bolted back in which drastically reduced the noise, and then I took it out for a test drive and it felt great, I adjusted the idle revs down and the engine was running just like how it was in my MR2.

Anyway, on Monday of Week 9 I then did a fresh oil change and also refilled the transmission with oil as it had gone quite low. On Tuesday I gave it a good blast around town and it is running very nicely with all its power and high revs. I will be continuing to get it ready for the owner to pick it up.
The funds from doing the job will help me a lot to support my electric conversion project.\

Also in week 8, I worked on CNC milling a test plywood rotor end cap, which I was very happy with. I used the plastic spline attachment piece to simulate the coupling. After talking to one of my stakeholders Mr Smith, we agreed on using a solid welded coupling to the motor as it will probably be the most reliable and strong.

I also wanted to get the design sorted for my battery pack. I have decided on getting a proper battery management system from Aliexpress which will balance and protect the batteries in many ways to extend their cell life. I want to use the Arduino microcontroller to build a monitoring system with temperature control, which I have trialled and tested all ready with good results (using thermistors).
I will buy these parts over the next few weeks to get onto building the battery pack.

My stakeholder Jared Cochrane also agreed with the idea to split the battery into 27 different modules which will each be wired in series to produce the desired 99.9V nominal volage up to 113.4V fully charged. This will make each module lighter and more portable, safer, and makes the maintenance easier. But will be slightly more complex and will require more production of battery holders. But the benefits of doing the design like this compared to as one big unit is the sizing is more flexible also and the packs could also be expandable later on if needed.

WEEK 7: Ignition Problems, Steel rotor success

After getting the engine in, it would not start. Even after hooking up all the coolant, fuel, vacuum and electrical lines, swapping over all my electrical components, it would not start at all. I spent pretty much the entire Saturday trying to figure it out, but with no success. I got no spark at all in the spark tests, which led me to doing a diagnosis using the check engine warning light.

By the blinking warning code I got, it showed that there was no ignition signal to the ECU, which meant that either the igniter was bad (which I knew was working), the ECU was bad (which I also knew was working) or there was a wiring fault (open or short circuit). My brother suggested looking into the wiring harness and find where the igniter pins go to, which I then discovered the wiring was slightly different in the fuse box, and the igniter was possibly not receiving any power, which is definitely not good.

By Sunday I decided to just get the car back on its wheels so it could be rolled around, so I bolted the subframe back in, pushed the axles into the transmission and bolted all the tie rods and control arms, alignment rods, etc. which I could then put the wheels back on. It could now be rolled around which was great. I still had no ignition which I will work on to figure out why it isn't going.

This is the wiring I will have to sort through :)

MR2 back on its wheels:

I also managed to get all the magnets aligned in my test steel rotor, which I then placed over a stator and powered it with a BLDC controller. And then it turned and turned, very slowly because it was completely rubbing against the stator but this was proof that my idea was working.

I will continue to develop the rotor concept and hopefully will begin cutting out the actual thing before the end of this term 2.

WEEK 6: Engine repairs and mounted in MR2, designing stator mount, CNC rotor

After rolling the steel rotor I CNC'd last week, I stuck a bunch of the magnets in place, but have found that the internal diameter is several mm too small, so the magnets are rubbing right against the stator. I think this has happened due to the MDF swelling up from the coolant I was adding, which messed up the rebate (1mm cut into the steel), but also the fact that the large steel sheet was slightly warped. So, from this testing I have done, I think I will cut a slightly large steel for the rotor diameter for be just right, even if it is just a little over, it is better than the rotor rubbing on the stators and wrecking havoc. I am excited to get underway with this as it will be one of the hardest parts of my project, so if it works out I will be so happy. I also have my 2 backup plans which is to use an old DC forklift motor which isn't as efficient but much easier to work on, or buying a proper electric car BLDC motor which will be very costly but the most efficient and powerful for my car!


Over the last week, I was pretty busy with getting the engine out and getting it ready for the other guy's MR2.

A summary of what I did:

A good clean and degrease of the engine, I removed my transmission and bolted his transmission on, I switched the water pump and cambelt before reassembly the covers, I then got the starter motor back in and rolled the engine under ready for mounting in his MR2.

It rained the next few days so I covered the engine before I was to get it after Friday.
So, on Friday I managed to get the car on the hoist and lowered it down onto one of its engine mounts which I loosely bolted it onto. This weekend I also was doing my 100 hour famine so I could not do too much after Sunday as I did not have the energy to (till Wednesday). But on Saturday I managed to get the second main engine mount on, which meant the engine was now held in well.
I then hooked up every single hose and electrical line, and swapping some connectors over as the wiring harness was slightly different.

After many hours of getting it all ready I tried to start it where the starter immediately turned on and started cranking the engine well, but it did not start! I had tried over 10 times after swapping other small electrical/mechanical components, but it was not going to start. After performing a spark test, there is no spark in the plugs, which meant there must be an issue with the electrical system somewhere. Over the next week I plan to get his car completely reassembled and on its wheels, and go from there to figure out how to get the engine running, as it was running perfectly fine before I took it out of my car.

Another thing I worked on is the stator mount (for the SmartDrive motors), as the 3 stators I am planning to use have to be very rigid in place to avoid the rotor from rubbing on them.

After talking to one of my Mechatronics stakeholders, Jared Cochrane, he agreed with the idea of using thick 12mm/14mm threaded rod through the 4 original stator mounting holes, with nuts on each side to clamp the stators in place. This also allows me to make fine adjustments to the stator positions to achieve good efficiency and then I can possibly weld them in place or loctite the nuts so they don't come loose as the motor will be spinning very FAST and will be susceptible to vibrations and harmonic frequencies. Another idea was to CNC mill flange plates for each motor out of a thick 10mm steel we have. I think this will greatly increase the rigidity and reduce flexing in the threaded rod, which is important as the electric motor has to be reliable.
Anyway, I will begin designing the mount next week to determine the rotor size so I can get to building it for real, fingers crossed it will work out!

WEEK 5: CNC routed rotor, Stripping Engine out of Car

This week was rather short with only 2 school days for me, I worked on setting up a cut file to cut a test steel rotor on the CNC router. My teacher Jared suggested using a rebate (in-cut) into the steel for the magnets to sit and align in which I thought was a great idea.

At present, the trouble I am having cutting out is the router bit getting too hot when cutting and requiring more water cooling if cutting fast. Because the CNC bed is lined with MDF (a soft absorbent manufactured wood), it tends to absorb the cooling water and swell up, causing the entire steel piece to move and mess it up.

Anyway, on Thursday afternoon I spent several hours after school cutting out the test steel rotor, which was looking good so far until I noticed the steel strip was being warped up quite a bit because of the MDF wood swelling up. I was close to finishing but will probably have to do the last few passes next week. Then I will try roll it and see how the magnets fit and if the internal diameter is right. For this test I used the exact diameter and lengths to calculate the cut file for the rotor, so I will see if I need any less or extra once I cut it out to determine what I need for the final product.

Also I had a buyer of the engine of my Toyota MR2 come round and have a test run of it. I agreed to do the engine swap over the weekend into his Toyota MR2. They brought their car over on a large truck which dropped it off down our driveway for me to get stuck into.

I first had to remove the engine from my car, which I took many photos beforehand in case I get stuck somewhere later on. This is by far one of the trickiest parts, I had to break many bolts loose holding both rear axles on, then had to remove the entire subframe of the car, then the exhaust muffler and manifolds had to come out, which the bolts were rusted over and stripped. I ended up drilling them out which worked fine.
I then had to disconnect everything, and I mean literally every single hose line, vacuum lines, coolant lines, clutch lines, shifter lines and of course all the wiring harness from the ECU.
Once everything was disconnected, I then loosened all the engine mounts and prepared to drop the engine out by lowering it to the ground and jacking the car up over it.
This worked well and after midnight on Sunday, I managed to have gotten the entire engine out and rolled out under the car.

The next day - Monday (week 6) I gave the entire engine a good clean for an hour so it would be way less greasy to work on.
The next few tasks were swapping some components from his old engine which are fairly new to the engine out of my Toyota MR2. I ended up swapping the alternator and water pump over, and after taking off the cam belt cover, I loosened off my old belt and tightened his newer belt on. After some more cleaning and sealing, the covers were back on and then my next job would begin.

As I had to swap the transmissions over as well, I broke all the bolts free with the breaker bar on Monday night in preparation to split the engine and transmission the next day.
On Tuesday morning, I woke up early to do 2 paper runs first before getting into splitting my transmission from the engine which went well and only took about an hour.

On Tuesday night at 11pm, I then spent a good 5 or 6 hours getting the engine entirely back together, which included a quick clean of the bell housing and mounting area, and removing the starter and clutch lines to get his transmission lined up. I was also considering swapping his clutch flywheel assembly over but since this is a risky job, and both assemblies look fairly the same in wear, I decided just to leave the clutch flywheel assemblies how they are. After finally managing to get the transmission loosely bolted together and the spline fit to the clutch plate inside the bell housing, I then fully bolted the 2 together, which was quite a tedious job as many of the bolts are hard to reach. I then put his starter motor back into the transmission and connected the clutch lines and engine mounts back on with their bolts. Finally I jacked up his Toyota MR2 as high as possible and rolled the engine underneath in preparation to install it into his car. As the weather is supposed to be rainy for the next few days I covered it with tarpaulins to protect it from the rain before I get back into it!

Anyway a lot of fun and pain and very late nights over the long weekend but I managed to get a lot done so I'm happy. I am also excited to now start designing the motor transmission layout for my electric conversion and get stuck into it.