Wednesday, March 29, 2006

Too good to last...

"The maintenance guy unplugged you. He say you be stealin' energy"- parking garage attendant.

Guilty. I didn't ask first because it was largely experimental and I wasn't sure I was going to continue driving this way. I plugged in without asking permission. I'm a baaaaaaad EV'er.

So after 2 days, the maintenance guy unplugged me. He had no idea what the vehicle was or what it was doing. He just did it because the parking garage is the only area in his tiny little life that he has any control over and by God he's going to exert control in his little sphere of influence every chance he gets. According to the parking attendant, he thought I was plugging in to heat the van. Oh man... Ok so my big, inefficient charger uses $1.52 to charge me up from "E" at home. I suspect my little charger uses .25 to .50 cents to charger me up from 2/3's. I explained that my charger uses less electricity than one of the garage light bulbs and I was advised to contact the regional county garage manager.

I called this gentleman and he seemed genuinely interested in helping me. He stated that I couldn't use those outlets (for reasons he declined to explain) and promised to "set something up" for me.

We'll see what happens. I can make it home ok without charging but it's a lot harder on the batteries.

Full power communting

"You're so clever!"- Friend

Yeah right. I'm such an amatuer.

With my new onboard 72 volt charger, I've bravely set off on my morning commute to the Metro station. The first time, I rolled into the station having used less than half of a full charge. I easily found a parking spot in front of a column that had a 110 volt outlet and plugged in. I set the charger for only 5 amps because I didn't want to overcharge the batteries while I was away for 10 hours. This charger is dumb and doesn't shut off automatically. At the end of the day when I returned, I found my charge up to about 80%. I learned I can safely increase the rate of charge to the max 10 amp output that this charger will give.

The drive to the station was great. At 4:30 a.m. there's no traffic so I'm not holding anyone up even though I can easily attain the speed limit. The lights are all green so I'm not wasting juice stopping and starting. The ramp that connects the secondary road to the Metro touches a major highway and has a steep hill but the Comuta handles it well. I just put on the flashers when I hit it. It's 45 seconds of delay for whoever is behind me. They can live with it.

The drive home is no problem either because in the afternoon the traffic pattern is horrible and I hit every single red light. I waste some juice by stopping and starting so many times but because traffic never gets above 35 miles an hour, I'm never the one holding things up.

I've learned that the key to maximizing your range really is to maintain maximum RPM's in the motor's main torque band so I keep the van in 2nd gear and wound up tight. I typically make it to the station with 2/3's charge left and that's at 33 degrees F which reduces my capacity.

I've also learned that "topping off" with the charger while I'm in the shower seems to help as well.

Monday, March 20, 2006

Respiration and Circulation

"What's it for?"- Drone at auto-parts counter

Every time I need an auto part I have the same conversation. It goes something like this:

Me: "I need a distributor cap, Bosch part #: xxyyzz."

Counter Drone: "What's it for?"

Me: "Does it matter? I just gave you the part number."

Counter Drone: "Yeah but what vehicle are you putting it in?"

Me: "What does it matter? Is there a law against putting German parts in an American vehicle?"

Counter Drone: "No, I just want to make sure you get the right part."

Me: "I know what part I need. I need a Bosch #xxyyzz. Don't look it up by vehicle, just plug the part number into the computer because my car is definitely NOT in your computer."

Counter Drone: "Yeah but what's it for??"

Me: (sigh) "A 1981 DeLorean DMC-12."

Counter Drone: (taps on keyboard) "That's not in here."

Me: "No shit. I told you that. Go get your boss. I know damn well what kind of parts my car takes and it's none of your business what the application is. All you need to know is that I need a Bosch xxyyzz."

Drone Supervisor: "Hi, can I help you?"

Me: "I need a Bosch part number, xxyyzz"

Drone Supervisor: "Sure, what's it for?"

Me: (Heavy sigh) "Forget it. Just forget it."

And so it was when I visited the local auto bone-yard for a blower that I could use to circulate heat and keep the windshield clear. I told him I just wanted any old working 12 volt "squirrel cage" blower. We went 'round and 'round until I snapped and said that if he wanted to know what kind of vehicle it was for, to just come out and take a look.

He stepped around the corner and stopped in his tracks. He called one of his destruct-o-drones over from dismantling a Mercury Cougar and told him to "go to bin 22 and give this guy whatever kind of fan he wants". $15.00 and a small, Bosch recirc fan later, I headed back home. That was less painful than a normal parts-house thank God.

There are vents remaining in the dash left from the original heating system. It used a gasoline (of all things) heater. Sounds scary and dangerous to me. I'm glad it was all ripped out before I bought the thing. I've already gone to the local parts place and bought generic ventilation duct tubing that will connet to the vents. The next step is to get to Home Despot or Not-Lowe's and buy a general-purpose enclsoure box. I intend to cut a hole, mount the fan and connect the ductwork to the box. I'll also dissect an old heater or hairdryer and mount the heating coil in the box.

I haven't really had a big problem keeping the windshield clear, but it's been cold and I'm sure sick of it. It's March but it's supposed to snow tomorrow. Blech.

Sunday, March 19, 2006

The struggle with brakes

"You have to be able to stop before you can go" - Dad

Lately I can't seem to get the brakes pedal to be as hard as I think it should be. I've tried everything. New master cylinder, one-man bleeder kits, Myti-Vac pump, you name it.

I'm not losing any fluid but it's just not as good as it could be. I bench-bled the master cylinder. Not long after I replaced the master cylinder, the snap ring popped free and I think the piston was travelling "out" of the bore more than it should have. I might need to remove it and bench bleed the thing again. What a hassle.

...And for Christ's Sake, someone send me some warmer weather PLEASE!!!!

Friday, March 17, 2006

EV life so far...

"Is that a Jeep?" - Suburban troglodyte standing on the curb.

Ok, if you're an American in your 30's and you think my triangle van looks like a Jeep then you drink way too much cough medicine.

It's St. Patrick's day and it's still cold enough to reduce my range. We had a couple of freak warm days that hit 80 degrees and the improvement was instantly noticeable. I drive the EV exclusively except for when I need extra speed or range. At my current rate of consumption I won't put gas in the DeLorean for over a month.

The DeLorean steering and handling has slowly degraded over the last year. Dry-rotted suspension bushings and worn out ball-joints are the cause and not only is the EV saving me fuel but it's also saving me from damaging my stainless pride any further while I set aside the cash for suspension parts.

The winter range limitation is bugging the crap out of me though. I promised myself I wouldn't drop $800.00 on a fancy compact onboard battery charger but there has to be a compromise between "nothing" and "too much". I was actually considering building a battery charger but I stumbled on a brand-new, simple battery charger on the internet for only $150.00. It's heavy, but compact, plugs into an ordinary 110v wall outlet and can assist in equalizing charges because it has a variable voltage output from 12 to 72 volts. I can charge 2, or all batteries or any combination in between. I can choose between 5 & 10 amps. Not fast, but adequate.

Now as liberal as Maryland is, it's still not California. We don't have "public charging stations" at every Park 'n Ride or Costco like Cali does. Even so, I did scope out lots of 110v power outlets at the Metro parking garage. I have a good, heavy gauge extension cord. If I can even park on the same row as one of these outlets, the van can charge up nice and slow for the 10 hours I'm away and I'll have a full charge to drive home on every day! I'm going to mount the charger under the passenger seat I'm fabricating.

I'm trying to decide between just plugging in and feigning ignorance if the garage employees catch me or actually asking permission and trying to explain my EV to a bunch of minimum wage workers who barely speak English and might turn me down just for spite and not because of any regulations.

At least now, I'm not always bound to stop when I hit the "point of no return". If there's an outlet where I'm going, and I have the time to let it charge, I can exceed 15 or 20 miles in one direction.

Sunday, March 12, 2006

System Refinements

TEHRAN, Iran (AP) -- Iran will no longer consider a proposal to move its uranium enrichment program to Russian territory and is instead considering large scale uranium enrichment at home, Foreign Ministry spokesman Hamid Reza Asefi told reporters Sunday.

It's now March 12th, 2006 and while I tinker and learn how EV's work, I read the news and watch situations like this with interest. I refuse to propagate any conspiracy theories or post any sort of doomsday rant. I'm just saying that it's nice to know that there's an alternative available to me, at least for local travel.

So far, I've logged almost 2,000 miles on the Comuta Van. Once the motor brushes were replaced, I haven't had a single blip of trouble. The weather has been in the 20's and low 40's for about a month now. This has reduced my range from around 40 miles to 26-28 miles. This isn't enough to get me to the Metrorail station but it is more than enough to get me to the heavy rail MARC train station. The MARC system leases track time from Amtrak and CSX. These are full-sized trains with big, comfy cars that are far cleaner and populated with far nicer people than the DC subway system. I really enjoy riding it but the downside is, it runs far few trains, costs a little more and requires much tighter timing of my daily schedule. Even so, it's a good deal because my company pays my rail costs 100%. Fortunately for me and Northrop Grumman, I've proven myself to be worth it.

I believe that in an EV, conserving every amp can help so I've replaced a lot of the exterior lighting with LED's. They last forever, draw almost no power and are almost as bright as lightbulbs if you get the clustered type. The Comuta Van, being an ex-Postal van had a lot of "marker lights". Take a look at a modern Postal truck and you'll see what I mean. Replacing all of these little guys will ease the load on the accessory battery.

I was only able to drive the van in warm (70 degrees F) weather a few times before winter set in. The motor controller it turns out, is not mounted in the best way. The thing gets very hot channeling all of those amps through to the motor and it should be mounted to a large, metal surface to draw off the heat. Whoever installed the controller here, mounted it to a ABS plastic surface. A few times while driving up long hills, I drove the controller into overheat protection mode. At first, it emits a tone by shifting the switching speed to warn you, but after that it automatically begins cutting back on the amperage to the motor. The effect is similar to running out of juice. You have to stop for a few minutes to let it cool down before it'll give you full power again. To combat this, I mounted a large heatsink to the controller and installed a muffin fan above it to keep the controller cool. I plan on re-mounting it to the firewall, which is a large aluminum surface.

The 25 year old brake master cylinder started leaking but a replacement was readily available at Advance Auto for $19.95. The Comuta Van was built with a lot of "of-the-shelf" parts from other common vehicles so I'm hoping to minimize the amount of hunting I have to do.

The Curtis battery gauge arrived and installed well. It took me a couple of tries to connect it to the traction pack correctly. I had a brain cramp and couldn't figure out which was the first or last in the daisy-chain.

I installed a shifter boot to keep the dust and road noise out. One day, a darling family member was sick of the split seat vinyl and bought me a "flaming dice" seat cover. As a joke, I completed the theme complete with dice tire valve stem caps, dice license plate screws, fuzzy dice, a giant dice gear-shift knob and a chrome, lo-rider steering wheel.

My other big improvement will be to replace the old glass type Buss-fuse-and-spaghetti fuse panel with a modern, blade fuse enclosed fuse block. I'll wire up some extra slots for more accessories like a 12v outlet to charge the cell phone and cheapy stereo system.

I'm also curious to see if it's possible to add 2 or 3 batteries in parallel to some of the batteries in the traction pack. Theoretically, this will deepen my "pool" of available amps, giving me greater range. It won't increase the voltage, or give me more speed but I want range. I need the system voltage to stay the same or my charger won't be able to charge the pack anyway. I'm not sure it'll work though because I'm not certain if the pack will discharge evenly when I drive. I could end up over discharging the parallel cells, killing them quickly, wasting money.

Saturday, March 04, 2006

The Fix is in.

"The electric motor itself needs no lubrication. However, the brushes should be checked every 6 months or 3,000 miles for tightness and proper length..."
- Comuta Car service manual

The weather is cold now. We've had a few snows. It's cold enough to reduce battery capacity to a level that prevents me from reaching the Metro station and coming back without charging up. It's not a great time to lie on the ground doing mechanical work.

Still, curiosity will drive me outside every time. I want to know what's wrong with the Comuta Van and how expensive it'll be. I suspect the potbox that attaches to the accelerator pedal. I'm betting the resistor windings are shot and the "drive" signal isn't being sent to the motor controller. I broke out the multi-meter and started tracing power:

  • 12 volts available from keyswitch to motor controller solenoid: Check.
  • Solenoid engages when key is turned: Check.
  • Resistance changes when key is on and accelerator pedal is depressed: Check. (This surprised me)
  • 72 volts being supplied to controller input when key is on: Check.
  • Controller outputs voltage to motor when pedal is depressed: Check.
  • Double-check that voltage from the controller is present at the cables attached to the motor: Check.

So juice is flowing through all parts of the system and is fed into the motor but the motor doesn't turn. Something is "open" in the motor. Eww....that's not good. By now I've posted a plea for help on the newsgroup and more than one person has told me to check the motor "brushes".

The Postal Van manual just tells you how to drive the thing. It contains no repair information at all. I hope that the info in the Comuta Car/Citi Car service manual is compatible. The van has almost 10,000 miles on it by now so I'm starting to believe that brushes are my problem. The brushes complete the circuit by maintaining contact with the spinning commutator. The commutator is a mass of copper that spins in the center of the motor. The 4 brushes are in holders touching the commutator every 90 degrees around the commutator. As they wear, a spring keeps drawing them tight against the commutator to maintain contact. Eventually they wear down until they are too short to touch and the motor stops.

I crawled under and removed a dust collar and the cooling fan hose. I can see something...with a spring and a wire attached. That must be it. I disconnected the spring and pulled out a stubby block of carbon. It's barely 1/4" long. I've isolated the problem. Now all I have to do is find replacements for a 25 year old GE motor.

Glen, the fellow who sold me the van is very courteous and knowledgeable. He was actually concerned about my "EV experience" and wanted it to be positive. He actually found the brushes from a couple of sources and sold them to me at the lowest price: $50.00.

Consider this: An oil change today costs anywhere from $17.00 to $60.00 depending on if you do the job yourself or have a Jiffy-Change do it for you. You do this every 3-5,000 miles. I paid $50.00 for a 10,000 mile "oil change".

All I had to do was unclip each brush and unscrew the little pigtail from each brush. I slipped each new one into it's holder, clipped the springs on and attached the pigtail. It took 20 minutes. No oil, no filter. No hazmat. I washed my hands with ordinary bar soap when I was done.


"You broke it already? See, this is not how to convince people that an EV is better"
- co worker

I've been putting a lot of short trips on the EV now and haven't had any problems. I'm about to retire my toolbox back inside the house because it's been so reliable. Of course it wouldn't have mattered given the problem that crept up...

Coming home one night from the grocery store, I stopped to make a right turn at a traffic light. I tapped the pedal to creep forward a bit...but nothing happens. A few more taps...nothing. I cycled the key switch and heard the solenoid click on and off which says that the motor controller is connected to the batteries. I shifted from reverse to 1st gear and tapped the pedal. This time there was motion. The light turned green and I drove home with no further issues.

Over the next 2 weeks, this happened 3 more times. Intermittant problems are the absolute worst to track down. I like things to be completely broken before I fix them. It takes some of the mystery out. Well I got my wish. Again, coming home from the store I cut through a library parking lot this time. I stopped at the stop sign, poised to make a right turn. Step on the pedal and nothing. No amount of fussing or picking would fix it this time. I was only a few hundred feet from home and the ground was level so I just pushed it home. The only real damage was done to my dignity. Now I'm dead in the water and the EV is an 1800 lb. lead weight.