Thursday, January 29, 2009

Clutch vs. Clutchless

This question has 2 angles. One is drivability and the other cost.

In an ICE, the clutch is used to allow the engine to idle and to bring the vehicle up to speed in 1st gear. Since in an electric motor the RPM is variable from 0 up to around 5000 the clutch is not necessary. So drivability is only about shifting from 2nd to 3rd etc without a clutch. Many cars are really smooth shifting, especially Honda's. Our current Toyota corolla wagon is pretty rough shifting so it wouldn't be fun to repeately shift without a clutch. It takes a few seconds longer to get the gears to mesh.

The question of cost and conversion simplicity is a no brainer. With a clutch, the flywheel, clutch and pressure plate are kept in place. This requires a coupler between the flywheel and e. motor shaft. It also requires that the position of the flywheel and the alignment of the e.motor shaft and the drive shaft be maintained. So, in my case using a flat piece of aluminum for the adapter plate required the flywheel to be machined down. The flywheel weight loss was good, but took a couple hours of machine time. The alignment of the coupler and the driveshaft was pretty critical too. This required an additional 4-6 hours of machining.

No clutch:
Another way to handle this would be to use two lovejoy jaw couplers ( the way they were intended. One would have a 1.125 inch keyed shaft for the electric motor and the other would have a splined shaft to match the spline on the drive shaft (in the car). The flywheel, clutch, and pressure plate would be removed completely. The adapter plate would be flat and the shaft alignment not as critical because the jaw couplers have a separator between them that gives a little, 1-2 degrees. So, you could almost hack together an adapter plate and the couplers would cost you $14-$26 each depending on your HP and the divider is about the same price. So for around $80 you could have a coupler. Matching the spline would be the trick, but should be possible.

Tuesday, January 20, 2009

Motor install

With great relief the motor installed great. Afraid the shafts wouldn't align, I was nervous until it popped into place. There was only one hiccup getting the flywheel on the adapter plate on the motor. The bolts I'ld gotten were too short and the torque to high so one bolt got stripped a bit. With longer bolts and lower torque to match the motor mount (aluminum) the adapter plate is on, with the flywheel, clutch and pressure plate. Its a heavy bugger, but still light enough for 2 of us to lift.

This video is the first power up of the motor in the car to an old battery. Notice how the battery goes dead and the flywheel starts grinding on the bellhousing when just a little resistance is put on the tire.

Starter chain ring removal

The starter chainring was making a wicked grinding noise on the inside of the bellhouseing. There must have been some tolerances off with the adater plate (bending) so I removed the ring by drilling into it and grinding the last little bit. Since it is pressed on, it fell right off when it was cut. Now onto the batteries and wiring.

Monday, January 12, 2009

Potentiometer installation

Zach and I installed the potentiometer on the upper firewall. This will be close to the control box and the controller for wiring. We used the original cable end with a cable clamp. An 'L' bracket was used to keep the cable in place and the adjusting nuts work too.

The ohms read from .3 to 4.7 on both the white and gray wires.

Thursday, January 8, 2009

Adapter plate

Marcus helped me counterbore the holes in the adapter plate by hand, rather than getting a $40 counterbore bolt. This keep the motor mount bolts on the inside of the adapter plate flush enough to clear the flywheel.

Here is the adapter plate bolted to the motor. Notice the motor bolts are ground off to clear the flywheel. The center hole was drilled with a rental 4 1/8 hole saw and lots of drilling oil.


This EV project has given me concrete reason to read and think more about energy.

It will be a long time until we see many EVs on the road. It could happen, but it won't. At over $40K the Chevy Volt will be way to expensive. I think that a 5 buck tax is the only way we can move to alternative fuels. Self guided conservation hasn't worked (and won't) with only a 5% decrease in use. Tax incentives are way to complicated and controversial. Import tax or blockades will only piss off our suppliers.

Clearly we need a path to alt. fuels because of pollution, global warming (possible), and keeping all that money home (foreign exports). Our cars are a good place to focus at about 45-55% of the petroleum use. With 65% imported oil we need to get 3x more efficiency out of our fleet than the current 19 MPG.

The options are:
  • Ethanol which messes with food prices
  • Methanol from coal has no existing distribution channel
  • Biodiesel has a limited supply (only a few mcdonalds)
  • Propane and diesel are good but only a small percentage more efficient 45-55% vs. 35-45%
  • Hydrogen is a battery technology not a energy source
  • So that leaves electric. With up to 89% efficient motors and a distribution network already in place it looks pretty good.
A $5 a gallon tax over time would give us money to fund a transition to renewable electric wind, solar, hydro, geo, nuclear and clean coal.

Tuesday, January 6, 2009

Flywheel and coupler

The flywheel and coupler arrived today back from the machinist. Tony Smith a local gunsmith and machinist did a great job! From the original Lovejoy L110 he machined a perpendicular surface, cut it to length and turned the end to fit snuggly in the flywheel. He also drilled and tapped the 6 holes. Since a tap for the original M12 x 100 bolts was impossible to find and expensive to buy we switched to 1/2 by 20.

Next he skimmed the outer flywheel surface to fit inside the flat adapter plate (1/2 inch aluminum).

The pilot bearing was bad so Tony knocked it out and I got a new one at a local auto parts store and lightly hammered it in. The old one was obviously bad and would have caused addition drag.

I highly recommend Tony for more EV work.

Saturday, January 3, 2009

Starter cover

Zach built a cover for the starter hole left when we removed the starter motor. We used a 1/4 inch alum plate I found when I dropped off the engine at the recycling place.