Wednesday, November 14, 2007

Legal to drive, and 100KM

I registered the volt914 yesterday. In Colorado, all that is required is:

  • A VIN verification form (get one filled out at any car dealer)
  • The original title
  • Proof of insurance
  • Driver's license
  • Normal registration fee
This presumes that you had the car legally registered when it was a gas vehicle. They retain the title, and the state will issue a new one for the new electric-only vehicle it has become.

Some day I'm going to get custom plates, but for now, I just wanted to be legal to drive. One caution - Colorado VIN verification forms have boxes for the type of vehicle - make sure to tell the car dealer that your car is all-electric *before* they fill out the form or the will habitually check the "gas" box.

Also, yesterday, I hit 63 miles on the odometer, which means the car has 100 kilometers on it as an electric. W00T! It still needs tuning (plus some other work - heaters, cosmetics, etc.), but that will have to wait a couple of weeks as my work schedule precludes me from doing much else with it for a while.

Sunday, November 11, 2007

Watering Batteries and Transmission Leak

I took the opportunity today to water the batteries. You want to do this about once a month - certainly you do not want the water level to drop down to the level of the lead plates or it can cause erosion and shorten the battery life. You make sure the batteries are fully charged, then take your jug of distilled water and fill each cell up to just below the filler cap neck. Here's one in progress in the rear compartment:

I discovered that the rearmost cells in the 5 rear batteries are nearly impossible to fill from the middle compartment, so I opened the rear trunk to access those cells:

The frontmost batteries in the rear battery box are also hard to reach, but if you push the decklid open far enough you can get the water in there:

I dropped one of my wingnuts and stuck my head under the car to retrieve it. While down there, I noticed that transmission fluid is dripping down from the motor / transmission mounting point. This is almost certainly a bad transmission mainseal. I did not replace it when I redid the clutch. It looks like I am going to regret that shortcut:

The worst thing about a leak is having to remove the motor & transmission to diagnose and fix it. The second worst thing is that, if it *is* the transmission mainseal, it has almost certainly impregnated the (brand new!) clutch disk with fluid, ruining it. I don't have time to mess with this now - I'll put a drip pan underneath to catch it until I can repair it.

In happier news, I drove to and from work on a test drive today. No problems at all - commuting will be very straightforward with the Volt914.

Saturday, November 10, 2007

A Good Day to Drive

I drove the car quite a lot today since the last post. I probably drove a total of about 15 miles, with the longest drive about 6 miles (I say "about" because I have not yet calibrated the electronic speedo. Tomorrow...). As a first step in deciding how to attack the acceleration parameters, I took a fairly long data dump - here is a chart showing some of the data from 2 minutes of that drive. First thing that jumps out is that the pedal is only pulling the throttle about halfway down. But it's not yet clear whether fixing that (or tweaking a multiplier variable in the controller) will help.

Car is road-worthy

I did a few miscellaneous things to make the car road-worthy. I adjusted the ride height, tweaked the clutch so I could shift well, and made sure the tires were well-inflated. I then took it for a 5-mile drive, at speeds up to 40MPH. Ran like a charm (acceleration is a little on the sluggish side, but nothing extraordinarily bad - I may be able to tune it up via the computer interface).

For those who were concerned about the noise the motor makes (in the previous video) I made the following video which shows what it *really* sounds like. Enjoy!

Friday, November 9, 2007

It's a car!

A quick update - Azure Dynamics was kind enough to point out some errors in my procedures, and I updated the controller with the parameters they gave me. And it's a car! Reasonably snappy acceleration and the "grinding / whining" is much lower (it sounds like a Jetson car now :-). I took my wife for a ride around the block. Well, 75% of the way around the block. I took a bump too fast and the controller turned itself off and would not turn on until things cooled down. I'll debug that tomorrow (and will adjust the ride height too).

Here's the very diplomatic message pointing out that I'm an idiot. Did I mention how fantastic Azure tech support has been?

Sunday, November 4, 2007

It's Alive!

Well, almost alive. Very, very slow. See this movie:

I spent the day yesterday disassembling the clutch & flywheel. Nothing was obviously wrong - I tweaked the tightness of the hub adapter set screws - and the hideous sound the motor makes was there even without the flywheel mounted. So, I reassembled it all, making sure all the bolts were torqued according to specs, and got back to tweaking DMOC parameters

The following are what I have tweaked so far

EEXMaxAccelPower = 43000 (was ~73000)
EE2NoRegenBat 100 (was 300)
EE2NoAccelBat 127 (was 360)
EEXNoIgnSwitch = 1 (was 0)

I set EE2NoRegenBat down so low because the regen was coming on all the time (as evidenced by the brake lights coming on). EEXMaxAccelPower had no perceptible affect. And nothing happened until I set EEXNoIgnSwitch to 1 (tells the DMOC it does not need an external "ignition switch" signal) and EE2NoAccelBat to 127 (it thought my batteries were way too low to run).

I suspect there is much tuning ahead of me. As usual, Azure Dynamics has been very helpful. I sent off a complete dump of parameters along with 30 seconds of data capture; we'll see what recommendations they have for tuning.