Do you have an old vehicle with a bad engine, but a perfectly good body? Does something inside you cringe every time you think of sending it away as scrap metal? Don’t throw it out just yet! Old cars with bad engines can be rescued by being used for an electric car conversion. By converting your old car to run on electricity, you can reduce your carbon footprint, reuse most of the original parts in your car, and rescue it from the landfill. Converting may sound like a daunting task, but thanks to the efforts of thousands of electric car converters who struggled with the process over the last several decades, all of the mistakes have already been made and now the process is much easier. Here, you can learn about how California residents Margaret Milton and Gordon Schaeffer overcame the technical difficulties of the conversion process. Their car is fully electric and can be plugged into a standard 3-prong outlet while its batteries are charged using a charger that is internal to the vehicle.
During the early 1980’s, Margaret’s husband Gordon organized meetings for the North Bay chapter of the Electric Auto Association. At that time, the meetings were purely theoretical and much time was spent chewing the fat about how best to build an electric car. However, no one had actually taken any initiative to carry out their plans. Gordon’s own excuse for not building an electric vehicle was that he already had access to a great public transportation system. One day, Margaret marched into the middle of one of their meetings and confronted Gordon and the boys: “At that point I said something to the effect of, ‘Hello? Have you noticed that I drive all over southern Marin County every day doing my job? C’mon, big talkers! I’ll buy the car, and drive it, too. Make me an electric.’”
Shortly afterwards, Margaret bought an old Datsun pickup truck with a bad engine for $400, then sold the engine and related parts for $300, leaving Gordon with an empty shell that he could use for building her electric vehicle. Gordon designed and installed the electric power system, using mostly war surplus and re-purposed items while Margaret assisted. They used lead-acid batteries to power their car and named it “Gordon Electric.”
Margaret and Gordon first used an orange aircraft generator as a motor, which was not intended for electric vehicles, but designed to generate 28V of electric power to run an airplane’s controls. However, by running electricity through it instead of cranking it from the other direction, it could be used to propel a car. The aircraft generator motor cost them only $100. Due to its original purpose as a generator, it had the ability to run backwards as well as forwards, giving the car the ability to recharge its batteries during breaking. Today, we call this process “regenerative breaking.” However, the aircraft generator motor had a few fatal flaws. For one thing, it was designed to be plugged into a spline and had no drive shaft. Gordon had to find an adapter for it to create a drive shaft, but the drive shaft was never strong enough and kept snapping off. Another problem was cooling the motor. The aircraft generator motor was designed to run hot, and be cooled by fast winds in the sky, so Gordon had to get an electric blower to keep it from overheating. Worst of all, it emitted a high-pitched screech that Gordon described as a “vacuum cleaner on steroids” while driving. Gordon was once pulled over by a concerned highway patrolman who wondered what was “screaming like a banshee.” Gordon explained to the highway patrolman that everything was fine, and was sent on his way, but decided that it was finally time to look for a quieter motor.
Thankfully, modern electric motors are designed specifically for electric vehicles and don’t have any of the shortcomings of an aircraft generator motor. Plus, they are very durable and estimated to last over a million miles. Margaret and Gordon now have a Prestolite MTC 4001 electric vehicle motor, which they still use today in their 1982 Volkswagen Rabbit. The motor has been used in all three of their electric vehicles, including their Datsun. The 1982 Rabbit has traveled over 98,000 miles on the Prestolite motor, and Gordon estimates that there are over 150,000 miles on the motor in total. The motor is powerful enough for highway driving, and so far it does not show any signs of age. In this photograph, the Prestolite motor is being installed in the 1982 Rabbit. The batteries and other components have not been added to the car yet, so the view of the motor is unobstructed.
Controlling the motor was another hurdle that Gordon and other electric car converters overcame. Originally, Gordon used twelve 6V lead-acid batteries for a total of 72 volts. He separated them into two 36V packs and flipped a switch that changed their wiring between parallel and series so that he could use only one or both of the packs at the same time. By using this setup and a coil of stainless steel wire that acted as a resister under his gas pedal, he was able to control the amount of energy that was transferred to the motor. However, the motor still started up too fast, sapping more energy than it needed from his batteries and giving him poor acceleration. The invention of Pulse Width Modulation (PWM) by Russco, Wiley, and others improved the operation of electric vehicles drastically. PWM works by delivering pulses of varying width from the batteries to the motor. The more one presses on the accelerator, the wider the pulses become. While modern PWMs were under development, Wiley gave Gordon the opportunity to conduct practical tests on them. According to Gordon, the transistors were the weak points of the early PWMs, but their performance improved dramatically as transistor technology improved. Gordon now uses a Curtis 1221C-7401 speed controller, which works very well.
Despite all the troubles that she experienced during the early years of driving her electric vehicle, Margaret has fond memories of that time. She says, “I remember making a see-through plastic hood for the engine compartment to show off the weird stuff inside. Building and maintaining an EV was an adventure, not to mention driving it around Marin. Those were the glory days–the eighties–for DIY electric car buffs. We would tow our vehicles to Rallies and shows, talking to people, handing our literature, and giving rides. There was an evangelistic fervor. We were special! We were the wave of the future!”
Margaret decided to trade in the Datsun for an orange 1975 Volkswagen Rabbit for her electric car, so Gordon took out all the electric parts and sold the empty Datsun for $100 to another person who wanted to build an electric vehicle from scratch. By 1990, the body of Margaret’s “Battery Bunny” had rusted so badly that she could see the road through the floor of the vehicle, and the steering system wasn’t much better. The electric motor and its components, however, were still working perfectly. Thus, she asked Gordon to build her the “Battery Bunny II” from a 1982 VW Rabbit that they found on sale for $400 in the local newspaper. The 1982 Rabbit was a diesel-powered car with a bad engine. Its previous owner had been stranded on the freeway, and was fed-up with its performance. If Margaret and Gordon had not rescued the Rabbit, it would have been sent to the scrap heap rather than converted into a functional electric car. Today, Margaret still drives this car for many of her trips, and Gordon borrows it from her frequently. After all, it is still her car.
Although lithium-ion batteries are gradually becoming cheaper, good old lead-acid batteries are still a good option for converters. Margaret paid $1,900 for her current battery pack, and finds the car useful for most shopping trips, doctor’s office visits, and other excursions within 15 miles of their home. With a new battery pack, the Battery Bunny II can go a maximum of 56 miles on a charge, but usually Margaret and Gordon only want to drive it about 25 miles per day. Gordon’s car is a 2002 Toyota Prius that sits in the driveway behind the Battery Bunny II, and is used mainly for long trips beyond the range of the electric car.
In addition to being better for the environment, driving the Battery Bunny II costs less than driving a gasoline-driven car. At night, demand for electricity is low, so power companies have surplus energy. PG&E, the company that supplies most of the west coast with electricity, shuts down fossil fuel-driven power plants at night, but does not shut down its nuclear, wind, geothermal, or hydroelectric facilities. Thus, it has a lot of cheap, green energy available to customers at night that often goes to waste because it is not utilized. Margaret charges her car at night when the price of electricity is 7.5₵ per Kilowatt-hour (kWh) rather than during peak demand times when electricity can cost up to 32₵ per kWh. By using a small meter inside the car, Gordon has calculated that it goes 2 miles for every kWh. This means that each mile costs them 3.75₵. Compare this to an internal combustion engine vehicle that gets 30 miles per gallon on fuel that costs $3.00 per gallon. That’s 10₵ per gallon; more than twice the cost of driving an electric vehicle! With rising gas prices, we can expect to see the gap between the cost of driving an electric vehicle and the cost of driving a gasoline-powered car increase drastically.
Converting an old car to run on electricity does take some time and effort, but thanks to the efforts of Electric Auto Association (EAA) members like Margaret and Gordon, the process has been streamlined and made much easier. Several people besides Gordon have used a VW Rabbit as a shell for converting, while others have opted for flashy and stylish cars. If you have an interest in converting your own car or if you would simply like to learn more about what to look for when buying an electric car, attending an EAA meeting or public car show is a good place to start. Margaret and Gordon now participate in the East Bay chapter of the EAA rather than the North Bay chapter, and take their car to an annual electric car show at Chabot College along with several other electric car owners.
To find your local Electric Auto Association chapter, visit http://www.electricauto.org/
Photo Credits: Gordon Schaeffer and Margaret Milton