Anyone who's been reading this blog for a while, knows that I have a Toyota MR2 electric hydraulic pump running the power steering system. Take the ICE engine out of a car, and chances are your power steering pump goes with it.
There are a few ways of dealing with this problem. One is to simply fore-go power steering. But unless you replace the steering rack with one that's geared for non power steering, that makes turning at low speeds rather like arm wrestling with Lou Ferrigno. The second is to build some apparatus for holding the old power steering pump onto the front of the electric motor, putting a pulley on the tail shaft of the motor and powering it off that. Of course, if the motor isn't spinning, you have no power steering. For me and I'm guessing many others, there simply wasn't enough room to incorporate something like that. You'd be surprised how many times you run out of room and 1/16th of an inch more was all you needed to make something fit.
The third, and perhaps most popular remedy is to use an electric power steering pump. There are a few OEM cars out their using such devices and the second generation Toyota MR2 was one of them. They cost somewhere around $300 to $400, they don't take up much room and its relatively inexpensive to have the custom hoses made to add them to the system.
On a normal car, they run all the time and you really wouldn't care because the alternator will just produce the energy it needs to work. But in an EV, you want to try and reduce parasitic loads. That pump can draw up to 85 amps in a hard lock! So the idea of having it run all the time was troublesome to me. To resolve that, I devised a system by where the pump stayed off when driving in a straight line, but would come on as soon as you turned the wheel a few degrees. I also added an off-delay relay so that it would remain on for 10 seconds after I was going straight. In this way, it wouldn't cycle on an off while I was going through a parking lot or some other place requiring a lot of turns.
But it wasn't a perfect solution, and I grew to dislike it for two reasons. One was that it proved to be dangerous. As is bound to happen when driving, it became necessary for me to quickly dodge something in the street. The amount of effort it takes to begin turning is massive. So when the pump kicks in, you just can't react quick enough to release the pressure. I ended up nearly steering right into the car next to me. It left me with a case of the sweats as I pondered the fact that I'd nearly caused an accident and destroyed all my hard work.
The second reason was that when I would have other people drive the car (something I do as frequently as possible) they had a difficult time getting used to that sluggish, stiff steering wheel when heading into a corner. I thought, "how can I convince people that EV's are fun to drive and just like any other car, only better, when they had to wrestle the steering wheel going into any turn? This was not the message I want to convey.
I thought I would simply put a latching switch into the system that would allow me to bypass the proximity switch on the steering column which would then turn the system on and leave it on until I pressed the switch again. Seemed like the perfect plan and I even had a great place to locate the switch in the cabin. So, before I took the car apart to work on the last motor problem, I ran a few tests to find out just how much power the pump drew when I was traveling in a straight line. It turns out that it draws less than 2 amps from the high voltage pack. That translates into something like 18 to 22 amps on the 12 volt system. Not trivial, but not too bad. The system is sized to accommodate it.
The point is, I could let the car sit idle running that pump and it would take over 60 hours for it to deplete the battery pack. That means in a standard commute to work, which takes 20 minutes, the power steering pump uses an extra... let me think... about, Oh I don't care!! It's seriously not enough for me to worry about AT ALL! Since the car has been on the road, I've left that switch engaged the whole time. My previous post detailed how I've experienced a boost in efficiency seemingly from the new brushes, so the change to the system of having this pump run all the time might have had an adverse impact on that, but it's not enough that I care.
The car drives like a normal car now, in almost all respects. I don't have to explain to people that drive it why the steering feels weird at first, and they don't have to experience the sharp jerk when the pump kicks on and they aren't expecting it. This is definitely the way to go.
By the way, I have turned it off a couple times. Sitting, waiting for my daughter to finish her choir practice, I left the car on so I could listen to the radio and enjoy the air conditioning, but I turned the pump off. Honestly, I'm not sure it was worth the effort of lifting my hand to press the switch.
Showing posts with label Power steering. Show all posts
Showing posts with label Power steering. Show all posts
Tuesday, June 5, 2012
Friday, June 25, 2010
All Systems Go
I ran a final check of the 12v wiring this morning, and after I was convinced everything was OK, I connected the 12v SLI battery. The car came to life just as one would hope. All systems checked out. With a couple minor adjustments, the 12v system was healthy and ready to go.
I ended up needing to move the proximity switch for the power steering pump about 1/8". The power steering pump wasn't cutting off. I also had so shim the aluminum plate that the vacuum pump sits on because it was rattling and making a lot of noise. I shimmed it, and anchored it down, and now the new vacuum pump is so much more quiet than the old one. It was worth every penny.
Once I was happy with all the 12v systems worked, I turned my attention to the high voltage system. I double checked everything and threw the breaker. No big arcs, and no loud pops, so that's good. It was time to start the car up. A twist of the key, a click of the main contactor, and the car was live. I gave it a little throttle and the wheels started spinning. Excellent!!
Now for the real test. Was there any more wobble in the drive line? I revved it up to 4000 RPM and... smooth as glass. Then I ran it through the gears to be sure the clutch was working OK. Everything checks out.
I have a few more things to do before I take it down and drive it. Unfortunately, no time to do any of that until next week. *Sigh*
I ended up needing to move the proximity switch for the power steering pump about 1/8". The power steering pump wasn't cutting off. I also had so shim the aluminum plate that the vacuum pump sits on because it was rattling and making a lot of noise. I shimmed it, and anchored it down, and now the new vacuum pump is so much more quiet than the old one. It was worth every penny.
Once I was happy with all the 12v systems worked, I turned my attention to the high voltage system. I double checked everything and threw the breaker. No big arcs, and no loud pops, so that's good. It was time to start the car up. A twist of the key, a click of the main contactor, and the car was live. I gave it a little throttle and the wheels started spinning. Excellent!!
Now for the real test. Was there any more wobble in the drive line? I revved it up to 4000 RPM and... smooth as glass. Then I ran it through the gears to be sure the clutch was working OK. Everything checks out.
I have a few more things to do before I take it down and drive it. Unfortunately, no time to do any of that until next week. *Sigh*
Tuesday, December 8, 2009
12 Volt System Tests Done (I Mean it this Time)
I got the replacement relay for the heater switch, dropped it in and it works just like it's supposed to. So here's how it works. The Car must be on for the heater fan to work. The heater fan must be on in order for there to be power delivered to the switch on the dashboard that turns on the heater. If the cars not on, no power to the switch. If the fans not on, no power to the switch. So there should be no way for the heater to be on unless the car is running and the fan is on. I'm trusting that means no exciting fires in my dashboard.
I got a bench power supply the other day. "What's that" you say? I'll explain. If you build any sort of electronic devices, you need some way of providing power to them to test them or operate them or whatever you have planned. Well a bench power supply lets you set the precise voltage and current (amps) you want to deliver to the equipment. "But Tim, you're not bright enough to build any high end circuitry" you say. Well, you're correct. But the great thing about these is that they can function as battery chargers.
You say "Well then, why don't you just buy a battery charger you dimwit?" Whoa, that was kind of harsh. The thing about these batteries that I'm allegedly getting someday is that they are 3.3 volts apiece. Not exactly your standard charger voltage. If one of them needs to be charged by itself for some reason, say it lags behind the others in the pack during a normal charge, then I can catch it up with this. I don't expect that to happen much because I plan to follow a fairly conservative approach to charging. But you never know.
Anyway, with that, I was also able to charge the 12 volt battery I'd installed a few weeks ago and have been running down ever since. With it nice and charged up, I felt it was safe to try that energy hog of a power steering pump. I'm pleased to say that the whole system worked flawlessly. I turned the wheels and the pump comes on right away. It stays on for 10 seconds after the wheels are straight again. If during that 10 seconds I turn the wheel again, the timer restarts. Plus no leaks! I'm very happy about that.
I also started modifying some of the carpet that lined the trunk, so that I can put it back in place. I have to cut out holes to accommodate the new equipment, but so far so good.
And you guessed it, still no word on the batteries.
I got a bench power supply the other day. "What's that" you say? I'll explain. If you build any sort of electronic devices, you need some way of providing power to them to test them or operate them or whatever you have planned. Well a bench power supply lets you set the precise voltage and current (amps) you want to deliver to the equipment. "But Tim, you're not bright enough to build any high end circuitry" you say. Well, you're correct. But the great thing about these is that they can function as battery chargers.
You say "Well then, why don't you just buy a battery charger you dimwit?" Whoa, that was kind of harsh. The thing about these batteries that I'm allegedly getting someday is that they are 3.3 volts apiece. Not exactly your standard charger voltage. If one of them needs to be charged by itself for some reason, say it lags behind the others in the pack during a normal charge, then I can catch it up with this. I don't expect that to happen much because I plan to follow a fairly conservative approach to charging. But you never know.
Anyway, with that, I was also able to charge the 12 volt battery I'd installed a few weeks ago and have been running down ever since. With it nice and charged up, I felt it was safe to try that energy hog of a power steering pump. I'm pleased to say that the whole system worked flawlessly. I turned the wheels and the pump comes on right away. It stays on for 10 seconds after the wheels are straight again. If during that 10 seconds I turn the wheel again, the timer restarts. Plus no leaks! I'm very happy about that.
I also started modifying some of the carpet that lined the trunk, so that I can put it back in place. I have to cut out holes to accommodate the new equipment, but so far so good.
And you guessed it, still no word on the batteries.
Saturday, November 28, 2009
A Rough Day In the Garage
Black Friday took on a completely different meaning for me yesterday. While most of this great capitalist nation was out shopping for bargains, I was in the garage experiencing a completely different sort of stress. There were a few other things my day had in common with all the shoppers; it was expensive, and by the end of the day I was frankly too tired to write about it.
Earlier in the week I got the bushing back I'd ordered from the machine shop. You may recall that I need to mount a pulley to the tail shaft of the 11" WaRP motor so that I can run my AC compressor off of it. The bushing is beautifully made, take a look:
It's milled from a solid piece of aluminum, the cylinder is keyed so that it won't spin on the motor shaft, and he even milled a little ridge on the front side that perfectly holds the pulley in place. Very nice work.
So I fit it onto the tail shaft of the motor, and immediately realized I had two problems. In order to get the groves on the pulley to line up with those on the AC compressor, I would need to mount the pulley so far forward that I won't be able to use the motor RPM sensor that I have. I hemmed, hahed and scratched my head for a while, but there is no getting around it. Fortunately, there is a new type of sensor available that should work, but that's another $100 toward the cause. The only thing I've found I hate more than having to build something twice, is having to buy something twice. Very painful.
Turns out that may all be moot, at least for now. I was very careful to build the bracket for the AC compressor so that the pulley was flush with the face of the motor. If it didn't line up right, the belt would come off or simply disintegrate with wear in a short time. As I looked further I realized that while I'd lined it up perfectly on one axis, there was a tilt to the motor that I hadn't matched with the compressor.
Sadly I had to admit that there was no way it would work in it's present state. In reality the only way to make it work was to rebuild the brackets completely. Of course the problem is that getting the alignment right on one axis was hard enough. Getting it right on two will be crazy hard and frustrating. I realized the best, and correct solution is to build the bracket so that it mounts to the face of the motor rather than the chassis. Obviously that will be another custom made machined part. But there's no getting around it, it's the right way to go. Ultimately I decided to shelve that work for now. I want to get the car on the road and the weather is beautiful right now, so the compressor and all it's supporting parts came out. Perhaps in April or so, it can rejoin the rest of the car.
Moving on, I decided to figure out and install the off delay timed relay for the power steering pump. I labored over the electrical diagram for some time trying to coax out the mysteries that it held. After a few dark incantations I was pretty sure that I had it correct, so I hooked it up and tried it. Well, it didn't do quite what I wanted. It came on with power constantly fed through one contact, but never moving to the timed contact. I re-evaluated and decided I'd seen my mistake and tried again. This time it worked! Once.
Apparently, I wasn't supposed to send 12 volts to a particular pin. It managed to trigger the coil once and likely fried it in the process. So, a replacement is on the way to the tune of $27. Not not too much, but frustrating none the less.
From what I learned yesterday, I'll be able to wire everything up so that I can just drop the new relay in place when it arrives. I'm hoping that today will be much more productive and less costly.
Earlier in the week I got the bushing back I'd ordered from the machine shop. You may recall that I need to mount a pulley to the tail shaft of the 11" WaRP motor so that I can run my AC compressor off of it. The bushing is beautifully made, take a look:
It's milled from a solid piece of aluminum, the cylinder is keyed so that it won't spin on the motor shaft, and he even milled a little ridge on the front side that perfectly holds the pulley in place. Very nice work.
So I fit it onto the tail shaft of the motor, and immediately realized I had two problems. In order to get the groves on the pulley to line up with those on the AC compressor, I would need to mount the pulley so far forward that I won't be able to use the motor RPM sensor that I have. I hemmed, hahed and scratched my head for a while, but there is no getting around it. Fortunately, there is a new type of sensor available that should work, but that's another $100 toward the cause. The only thing I've found I hate more than having to build something twice, is having to buy something twice. Very painful.
Turns out that may all be moot, at least for now. I was very careful to build the bracket for the AC compressor so that the pulley was flush with the face of the motor. If it didn't line up right, the belt would come off or simply disintegrate with wear in a short time. As I looked further I realized that while I'd lined it up perfectly on one axis, there was a tilt to the motor that I hadn't matched with the compressor.
Sadly I had to admit that there was no way it would work in it's present state. In reality the only way to make it work was to rebuild the brackets completely. Of course the problem is that getting the alignment right on one axis was hard enough. Getting it right on two will be crazy hard and frustrating. I realized the best, and correct solution is to build the bracket so that it mounts to the face of the motor rather than the chassis. Obviously that will be another custom made machined part. But there's no getting around it, it's the right way to go. Ultimately I decided to shelve that work for now. I want to get the car on the road and the weather is beautiful right now, so the compressor and all it's supporting parts came out. Perhaps in April or so, it can rejoin the rest of the car.
Moving on, I decided to figure out and install the off delay timed relay for the power steering pump. I labored over the electrical diagram for some time trying to coax out the mysteries that it held. After a few dark incantations I was pretty sure that I had it correct, so I hooked it up and tried it. Well, it didn't do quite what I wanted. It came on with power constantly fed through one contact, but never moving to the timed contact. I re-evaluated and decided I'd seen my mistake and tried again. This time it worked! Once.
Apparently, I wasn't supposed to send 12 volts to a particular pin. It managed to trigger the coil once and likely fried it in the process. So, a replacement is on the way to the tune of $27. Not not too much, but frustrating none the less.
From what I learned yesterday, I'll be able to wire everything up so that I can just drop the new relay in place when it arrives. I'm hoping that today will be much more productive and less costly.
Monday, November 16, 2009
Power Steering Leak Solved
At least I think it is. Truthfully, I'm desperately hoping it is.
A friend pointed out that you must be careful with some hydraulic fittings not to over torque them. Some require a mere quarter turn after they seat, others as little as 12 lb/ft of torque. Well I cleaned the fitting and the threads in the pump and gave it a go. I put some fluid in it and... it leaked like a sieve.
I noticed at that point that the tubing that passes through the fitting was completely loose. Clearly, it wasn't seated to the pump properly. I began to wonder if the fitting simply wasn't deep enough to press the tube to it's receptacle in pump. I measured the depth and the length of the threads on the fitting and found the threads were .4 of a millimeter longer. Ok, so if I cinched it down all the way, that should produce a tight fit.
I tightened it down, added fluid and waited. 2 hours later, no sign of any leak. I really hope that it behaves the same under pressure.
A friend pointed out that you must be careful with some hydraulic fittings not to over torque them. Some require a mere quarter turn after they seat, others as little as 12 lb/ft of torque. Well I cleaned the fitting and the threads in the pump and gave it a go. I put some fluid in it and... it leaked like a sieve.
I noticed at that point that the tubing that passes through the fitting was completely loose. Clearly, it wasn't seated to the pump properly. I began to wonder if the fitting simply wasn't deep enough to press the tube to it's receptacle in pump. I measured the depth and the length of the threads on the fitting and found the threads were .4 of a millimeter longer. Ok, so if I cinched it down all the way, that should produce a tight fit.
I tightened it down, added fluid and waited. 2 hours later, no sign of any leak. I really hope that it behaves the same under pressure.
Friday, November 13, 2009
More Power Steering Fun
I rigged up the proximity switch for the power steering pump earlier. It was tricky work because there is a very small threshold to place the switch so that it will work properly. However, with a little work, I got it right where I want it. The switch will come on only after about I've turned the wheel to about 45 degrees off straight. Changing lanes shouldn't cause the pump to come one, but if making a real turn, it should come on in plenty of time to assist.
I also filled the power steering system with fluid. Though I hooked up the lines a while ago, I just didn't have any fluid to put in the system. After about 5 minutes, my worst fear was evident on the floor. Sure enough, there is a small but steady drip from the point where the new high pressure hose attaches to the pump. That can't be good.
I've drained the system for now. Now I have to go figure out how to fix it. Bleh.
I also filled the power steering system with fluid. Though I hooked up the lines a while ago, I just didn't have any fluid to put in the system. After about 5 minutes, my worst fear was evident on the floor. Sure enough, there is a small but steady drip from the point where the new high pressure hose attaches to the pump. That can't be good.
I've drained the system for now. Now I have to go figure out how to fix it. Bleh.
Tuesday, November 3, 2009
Wiring Up Part I
Today was the day to start running power to all the auxiliary electrical equipment. It went fairly well, and I got quite a lot done. Here's a quick list of the bits that are ready.
1. Pedestrian horn with momentary switch (press it, it's on; let it go, it's off).
2. Motor cooling blower.
3. Vacuum pump for the brakes.
4. Water pump to cool the Zilla Controller.
5. Fuse box for all components switched on by ignition switch.
6. High power lines to the power steering pump.
I still need to install the proximity switch for the power steering pump as well as wire the off delay relay, but the schematics for that relay are a bit over my head. I'm going to have to ask someone to help me decode it.
So that was all the easy stuff. Onto more difficult things tomorrow.
1. Pedestrian horn with momentary switch (press it, it's on; let it go, it's off).
2. Motor cooling blower.
3. Vacuum pump for the brakes.
4. Water pump to cool the Zilla Controller.
5. Fuse box for all components switched on by ignition switch.
6. High power lines to the power steering pump.
I still need to install the proximity switch for the power steering pump as well as wire the off delay relay, but the schematics for that relay are a bit over my head. I'm going to have to ask someone to help me decode it.
So that was all the easy stuff. Onto more difficult things tomorrow.
Tuesday, October 20, 2009
Power Steering Pump
Well, after a two week hiatus (which I took unwillingly) I'm back working on the car. Today was the day to mount the power steering pump. I got the high pressure line back from the custom hose shop, and it looked perfect. They really did a good job. I figured the next thing to do was to see if all my measurements were correct, and if it actually fit.
Since the engine is gone, the means of driving a traditional power steering pump went with it. The most common solution amongst EV'ers that need power steering is to use an electric power steering pump. The most popular is the pump that Toyota put on the 2nd series MR2. If you're lucky, you can get one cheap at a salvage yard. If you're like me, there aren't any at any of the salvage yards in a 100 mile radius, which means they aren't cheap.
I put the pump in the fitting we'd made for it and began assembling the lattice work of steel I'd built to hold it, when I realized there was a better way. I've made an effort to avoid building things twice. In other words, build it once only to realize I'd missed something and then have to rebuild it. But in this case, it was clear I could do it much better. So, some quick measuring, steel cutting, shaping and drilling, and it was ready to go. I was actually able to eliminate twice as much steel as I added, so that's a nice bonus.
Once I got the pump mounted, I ran the new line to it, and it fit perfectly. Ok, it is a tad too long, but that's better than the alternative! Next, I had to figure out where to mount the power steering fluid reservoir.
I had an idea where I would put the reservoir, but hadn't sorted out how I would do it. A moments thought, and I figured it out. I quickly mounted it up and then ran the original feeder line from it down to the pump, only to find it was too short. A quick trip to the auto supply store, and I had one slightly longer hose.
All the mechanical aspects of the power steering system are done. I just need to fill it with fluid, and hope that there are no leaks. That's one more task finished, and that much closer to getting her on the road.
Since the engine is gone, the means of driving a traditional power steering pump went with it. The most common solution amongst EV'ers that need power steering is to use an electric power steering pump. The most popular is the pump that Toyota put on the 2nd series MR2. If you're lucky, you can get one cheap at a salvage yard. If you're like me, there aren't any at any of the salvage yards in a 100 mile radius, which means they aren't cheap.
I put the pump in the fitting we'd made for it and began assembling the lattice work of steel I'd built to hold it, when I realized there was a better way. I've made an effort to avoid building things twice. In other words, build it once only to realize I'd missed something and then have to rebuild it. But in this case, it was clear I could do it much better. So, some quick measuring, steel cutting, shaping and drilling, and it was ready to go. I was actually able to eliminate twice as much steel as I added, so that's a nice bonus.
Once I got the pump mounted, I ran the new line to it, and it fit perfectly. Ok, it is a tad too long, but that's better than the alternative! Next, I had to figure out where to mount the power steering fluid reservoir.
I had an idea where I would put the reservoir, but hadn't sorted out how I would do it. A moments thought, and I figured it out. I quickly mounted it up and then ran the original feeder line from it down to the pump, only to find it was too short. A quick trip to the auto supply store, and I had one slightly longer hose.
All the mechanical aspects of the power steering system are done. I just need to fill it with fluid, and hope that there are no leaks. That's one more task finished, and that much closer to getting her on the road.
Friday, October 9, 2009
Power Steering Line
Well, I did manage to get something done this week, in spite of that horrible flu that was trying to keep me down. I carefully measured out the new power steering line that I need fabricated. I took the measurements, photographs and drawings I made down to Alternative Hose in Phoenix and showed them what I need. They were all over it. They had the right fittings and had a plan straight away.
I expected it would take a week or so to get the hose done, but these folks are serious about getting their customers fitted with hoses and fitted quick. The guy I worked with apologized because they were busy that day, consequently it wouldn't be ready for 2 and 1/2 hours. That caught me way off guard; I would have planned my day differently to take advantage of that. But since I didn't anticipate such quick turnaround, I didn't plan for it, and my schedule happens to be tied up for a while. I can't pick it up until October 19th! I'll have to wait until then to examine what I'm sure will be some top notch work.
I expected it would take a week or so to get the hose done, but these folks are serious about getting their customers fitted with hoses and fitted quick. The guy I worked with apologized because they were busy that day, consequently it wouldn't be ready for 2 and 1/2 hours. That caught me way off guard; I would have planned my day differently to take advantage of that. But since I didn't anticipate such quick turnaround, I didn't plan for it, and my schedule happens to be tied up for a while. I can't pick it up until October 19th! I'll have to wait until then to examine what I'm sure will be some top notch work.
Thursday, October 1, 2009
The Last of the Mechanical Stuff
It's a late post today; it's been a busy day. Let's see...
I built the support for the tray that will hold the Zilla and the Hairball, and mounted it in place. Looking at the space, it's clear that some of the electrical stuff will have to be placed under that tray. There simply isn't enough room on top. So I laid it all out on the garage floor, trying to pick the items that were likely to need any attention after install. Apart from a failure of any one component, I think I'm set. There is one thing I'm going to have to do, and that's to sort out what the remaining wires from the cars electrical system do. There aren't many, but I need to track them down. Bleh, not looking forward to that.
I took off the power steering line that ran from the old pump to the steering rack. I took several careful measurements and soon will be taking the old tube and the new pump down to a shop that can custom fabricate a new line. I'm dreading how much that's going to cost.
Spent some time cutting and fitting some duct work for the fan that will blow fresh air into the back battery box. It will be controlled by a thermal switch in the box.
With the completion of the power steering pump, and then mounting up the A/C compressor, there will be no more major mechanical things left to do. At that point, it will be just sorting out the electrical stuff. The truth is, what remains for the A/C and the power steering are pretty minimal, so I'll be setting those aside until I have all the parts. That means I'll be starting all the electrical work in earnest tomorrow.
I built the support for the tray that will hold the Zilla and the Hairball, and mounted it in place. Looking at the space, it's clear that some of the electrical stuff will have to be placed under that tray. There simply isn't enough room on top. So I laid it all out on the garage floor, trying to pick the items that were likely to need any attention after install. Apart from a failure of any one component, I think I'm set. There is one thing I'm going to have to do, and that's to sort out what the remaining wires from the cars electrical system do. There aren't many, but I need to track them down. Bleh, not looking forward to that.
I took off the power steering line that ran from the old pump to the steering rack. I took several careful measurements and soon will be taking the old tube and the new pump down to a shop that can custom fabricate a new line. I'm dreading how much that's going to cost.
Spent some time cutting and fitting some duct work for the fan that will blow fresh air into the back battery box. It will be controlled by a thermal switch in the box.
With the completion of the power steering pump, and then mounting up the A/C compressor, there will be no more major mechanical things left to do. At that point, it will be just sorting out the electrical stuff. The truth is, what remains for the A/C and the power steering are pretty minimal, so I'll be setting those aside until I have all the parts. That means I'll be starting all the electrical work in earnest tomorrow.
Thursday, September 24, 2009
Power Steering Switches
I've mentioned earlier in the blog that I'm not the only person to have undertaken transforming a Z3 to an EV. A gentleman by the name of Len, who happens to reside in Malta started his conversion within a week of when I started mine. Well, he is clearly more skilled than I because his has been up and running for nearly 2 months now.
Len had figured out how to create a position sensitive assembly for the steering column that will turn the power steering pump on as soon as the steering wheel is not straight ahead. Since there is no need for power steering when you're driving in a straight line, this will help to reduce the draw on the batteries and increase range.
Earlier today, a package arrived on my doorstep from Len. He was kind enough to send along the necessary switch, shims, spacers and plans for how to duplicate the assembly on my car. What great and generous thing to do. Thank you Len!! I am most grateful.
Isn't Malta beautiful?
Len had figured out how to create a position sensitive assembly for the steering column that will turn the power steering pump on as soon as the steering wheel is not straight ahead. Since there is no need for power steering when you're driving in a straight line, this will help to reduce the draw on the batteries and increase range.
Earlier today, a package arrived on my doorstep from Len. He was kind enough to send along the necessary switch, shims, spacers and plans for how to duplicate the assembly on my car. What great and generous thing to do. Thank you Len!! I am most grateful.
Isn't Malta beautiful?
Wednesday, August 19, 2009
Battery Support Part V
This may be the last post were the focus is battery support. Today my friend Tim and I welded up what should be the last of the bracing to support the battery trays. With the choice of the newer lighter batteries, I'm confident that the bracing is more than up to the task.
Here you see the cross bracing we put together on the passenger side of the car. The other side is similar.
This is a shot of the new trays I built out of 14 gauge steel. All in all, it saved 15 lbs of weight swapping the heavier ones out. With the batteries being lighter than the lead acid I'd planned, I no longer need the trays themselves to be a structural support, they just need to hold the boxes in position. You'll notice that the box in the back is smaller than the tray. Well that's the one I mentioned I was going to have to have redone. You can see the size of the footprint the box will take up has grown a bit.
I'm leaving the heavier tray at the very front because the power steering pump will be suspended from that one. It's going to need the strength.
Last is a shot of all the boxes in place. I haven't secured the trays down to their moorings just yet; I'll be doing that tomorrow. There's only a few more mechanical items to sort out now; mounting the blower fan for the motor, the vacuum pump for the brakes and the compressor for the A/C system. The compressor is going to be a challenge. It may not be running when the car hits the road, but it will need to be working before next summer.
Here you see the cross bracing we put together on the passenger side of the car. The other side is similar.
This is a shot of the new trays I built out of 14 gauge steel. All in all, it saved 15 lbs of weight swapping the heavier ones out. With the batteries being lighter than the lead acid I'd planned, I no longer need the trays themselves to be a structural support, they just need to hold the boxes in position. You'll notice that the box in the back is smaller than the tray. Well that's the one I mentioned I was going to have to have redone. You can see the size of the footprint the box will take up has grown a bit.
I'm leaving the heavier tray at the very front because the power steering pump will be suspended from that one. It's going to need the strength.
Last is a shot of all the boxes in place. I haven't secured the trays down to their moorings just yet; I'll be doing that tomorrow. There's only a few more mechanical items to sort out now; mounting the blower fan for the motor, the vacuum pump for the brakes and the compressor for the A/C system. The compressor is going to be a challenge. It may not be running when the car hits the road, but it will need to be working before next summer.
Friday, August 14, 2009
Odds & Ends Part V
Well, it's been a very busy week and today was the first chance I've had to work on the Z3. Let's tally up what I did, shall we?
1. Finished the mount for the box that's going in the trunk. It will fit through the hole I've cut and into the cavity that was occupied by the fuel tank. Luckily, there was a mounting bracket welded to the chassis in very nearly the perfect spot for use to support the box. I cut a piece of light steel to bolt to it, and the box will simply rest on it, kind of wedged into place. I'll clamp it down on the front edge, and that will prevent it from moving at all.
2. I also cut a 2 inch hole in the back of the box. I will connect some ducting to it and it will do one, possibly two things. It will provide fresh air to the fans of the charger while it is running, and it may also be the conduit for the AC power line to the charger. I might just drill a separate hole for that so there is nothing in the tube obstructing air flow.
3. I figured out how I'm going to mount the power steering pump. I had decided that I would simply suspend it from the front battery box making use of the room there. Today I cut and fitted all the steel needed to support it. Next up for that is simply weld the steel up and then drill out a few holes so that I can mount it in place, easily removing it if necessary.
4. One of the biggest pieces of news this week is I've opted to scrap the idea of lead acid batteries in favor of Sky Energy LiFePo4 batteries. I'd come across a fabulous series of videos put together by a gentleman by the name of Jack Rickard, in which he talks about how best to treat LiFePo4 batteries. All fascinating stuff, but what really caught my attention was the price he mentioned that he paid for the batteries. When I started looking into the project a year and a half ago, a similar pack of Thunder Sky's would have run me over $20,000. Well they've come down substantially, making them much more economically viable. Jack was kind enough to answer some of my questions, and encourage me along. If you care to check out his project, you can see it here. First rate stuff!
The Sky Energy's will weigh in at 475 lbs, versus the 737 lbs that the lead acid I had intended to use would have weighed. In addition, if handled properly, they are rated to handle 3000 charge/discharge cycles. That amounts to approximately 150,000 miles, or for all practical purposes, the life of the car.
5. To that end, I need to redesign one of the battery boxes and the tray that holds it to accommodate the different shape of the batteries. Fortunately, there is no need to adjust any of the bracing that we'd welded up over the past few weeks. However, I will be able to reduce the weight of two of the trays used to hold the battery boxes. The two trays weigh in at about 32 lbs, and I should be able to drop that to about 10. Today I took all the necessary measurements and began cutting up the new lighter steel to hold it all.
That's all for now. Hopefully next week, I'll have more time for the project.
1. Finished the mount for the box that's going in the trunk. It will fit through the hole I've cut and into the cavity that was occupied by the fuel tank. Luckily, there was a mounting bracket welded to the chassis in very nearly the perfect spot for use to support the box. I cut a piece of light steel to bolt to it, and the box will simply rest on it, kind of wedged into place. I'll clamp it down on the front edge, and that will prevent it from moving at all.
2. I also cut a 2 inch hole in the back of the box. I will connect some ducting to it and it will do one, possibly two things. It will provide fresh air to the fans of the charger while it is running, and it may also be the conduit for the AC power line to the charger. I might just drill a separate hole for that so there is nothing in the tube obstructing air flow.
3. I figured out how I'm going to mount the power steering pump. I had decided that I would simply suspend it from the front battery box making use of the room there. Today I cut and fitted all the steel needed to support it. Next up for that is simply weld the steel up and then drill out a few holes so that I can mount it in place, easily removing it if necessary.
4. One of the biggest pieces of news this week is I've opted to scrap the idea of lead acid batteries in favor of Sky Energy LiFePo4 batteries. I'd come across a fabulous series of videos put together by a gentleman by the name of Jack Rickard, in which he talks about how best to treat LiFePo4 batteries. All fascinating stuff, but what really caught my attention was the price he mentioned that he paid for the batteries. When I started looking into the project a year and a half ago, a similar pack of Thunder Sky's would have run me over $20,000. Well they've come down substantially, making them much more economically viable. Jack was kind enough to answer some of my questions, and encourage me along. If you care to check out his project, you can see it here. First rate stuff!
The Sky Energy's will weigh in at 475 lbs, versus the 737 lbs that the lead acid I had intended to use would have weighed. In addition, if handled properly, they are rated to handle 3000 charge/discharge cycles. That amounts to approximately 150,000 miles, or for all practical purposes, the life of the car.
5. To that end, I need to redesign one of the battery boxes and the tray that holds it to accommodate the different shape of the batteries. Fortunately, there is no need to adjust any of the bracing that we'd welded up over the past few weeks. However, I will be able to reduce the weight of two of the trays used to hold the battery boxes. The two trays weigh in at about 32 lbs, and I should be able to drop that to about 10. Today I took all the necessary measurements and began cutting up the new lighter steel to hold it all.
That's all for now. Hopefully next week, I'll have more time for the project.
Wednesday, February 25, 2009
Odds and Ends: Part I
Spent the whole day doing a variety of tasks, and yet it felt like I made no progress!! In retrospect, I guess it wasn't all bad. I worked on getting the gas tank out. I mentioned earlier that I'm going to be cutting it to pieces rather than taking apart the entire back half of the car. It's plastic after all. Crazy, perhaps, but so far so good. Oh and yes the tank is completely empty with no smell of gas what-so-ever. Even so, I have two extinguishers at the ready.
I spent a couple hours cleaning and degreasing the engine bay. 134K miles of road grime! Now I can work in the space without looking like an oil rigger from the 1800's.
I carefully measured off and marked the area that I'm going to be cutting from the floor of the trunk. Once I get a box built for the space I will be able to suspend 4 batteries below the floor of the trunk. I can put the carpet back over it and still have space to haul lumber and what-not.
Last, I drained the power steering system. I need to remove the old power steering pump, but there's a problem. It's not attached to anything anymore and the nut that holds the high pressure hydrolic line on the pump was tightened by an angry gorilla. The bottom line is that I can't hold the pump still AND put enough torque on that bolt to break it free. I'm going to need to start pumping some serious iron, or try channeling the spirit of Archimedes.
I spent a couple hours cleaning and degreasing the engine bay. 134K miles of road grime! Now I can work in the space without looking like an oil rigger from the 1800's.
I carefully measured off and marked the area that I'm going to be cutting from the floor of the trunk. Once I get a box built for the space I will be able to suspend 4 batteries below the floor of the trunk. I can put the carpet back over it and still have space to haul lumber and what-not.
Last, I drained the power steering system. I need to remove the old power steering pump, but there's a problem. It's not attached to anything anymore and the nut that holds the high pressure hydrolic line on the pump was tightened by an angry gorilla. The bottom line is that I can't hold the pump still AND put enough torque on that bolt to break it free. I'm going to need to start pumping some serious iron, or try channeling the spirit of Archimedes.
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