End of Day 2

Most of today was spent just taking the car apart. My friend Pete came over for lunch and we removed the front and rear trunk lids. We also drained the fuel tank by operating the fuel pump with a 12V gelpack battery and took out the fuel tank. I even went so far as to yank out all the fuel lines that go down the center tunnel of the car. There's no going back to gasoline now!

I continued to spend most of the evening disconnecting cables, hoses and wires to allow the engine to be removed from the car. I didn't have the proper tool to disconnect the shifting linkage, so that will have to wait until tomorrow. Craigs 12-point tool for removing the CV joints worked like a charm.

Big thanks to Pelican Parts for their technical article on how to easily drop an engine:

http://www.pelicanparts.com/techarticles/914_engine_drop/914_engine_drop.htm


Pete helping me remove the fuel system and front/rear trunk lids.

Fuel compartment without fuel tank.


The empty fuel tank with separated expansion tank (to remove the fuel guage plug).
Note the two hydraulic jacks near the wall. Having two jacks makes dropping the engine much easier.


Rear trunk lid removed.


Method of connecting 12-volt gel-cell to fuel pump to dump fuel into gas can.


The front and rear trunk lids, removed.


The car jacked up and held with a hydraulic jack and two jack-stands per side.


An unseparated CV joint with two 12-point bolts showing.


The CV joint separated and protected with a plastic bag.

I'm covered with grease and looking forward to a good night's sleep.

Hanging out with the OEVA folks

In addition to starting the conversion, the OEVA had their monthly meeting this evening. I got to chat with a bunch of folks about battery management systems and share my excitement over starting the 914EV conversion.


Keith on his all-electric scooter


Demonstration of a battery equalization system that uses one charger per battery after the main charger finishes with the bulk charge.

Whew, what a day. I'm going to bed now.

Day 1

Here is some progress in the first two hours:

Covering wrenches with blue electrical tape for battery work.


Removing the Engine Cover


Taking out the Battery


Removing the starter wire from the positive battery terminal


Uncovering the fuel pump for draining gasoline


Taking out the "classic" WoooGaaa horn

The next step will be to take off the front and rear hood lids, which I'll need an assistant.

The desulfation experiment continues

On a more process-oriented note, the 8-volt battery sitting on the desulfator is up to 9.1 volts (from 7.95 volts), so I have warm fuzzies that the desulfation system is working somewhat. I'll wait until the battery gets up to 9.6 volts (float voltage) and see what the specific gravity is. If this experiment works, I might splurge and purchase a $500 super-desulfator and offer to desulfate batteries for the OEVA club. The super-desulfator is 25 times as powerful as the one I have now and should desulfate a 70 pound battery in three days (whoosh!).

On the battery equalization front, I got some feedback regarding the flying capacitor circuit that I presented in a prior blog entry. While the flying capacitor approach is elegant and simple, it just isn't effective in a practical system because very little charge is transferred as the voltage on the batteries approach each other. A more effective system was designed by Lee Hart. The schematics and other info is located at the following link:

http://www.geocities.com/sorefeets/balancerland/index.htm

The major drawback of Lee's system is that it's expensive. The OEVA club is looking into this and I hope to cost reduce the system to be only $20 per battery. Perhaps using a PIC microcontroller and slightly lower currents will help. My engineering buddies are looking into this now.

Let the Conversion.... Begin!

I just got back from A & P Specialties where Alan replaced the suspension on the 914 and did a steam cleaning in the engine compartment. Without the battery weight and having the unaligned suspension, the car rides unstable and high. No matter, I'm going to start preparing to drop the engine this weekend. I ran out and got another floor jack and a water-proof label-maker so I can mark all the wires and hoses as I take them out.

Today is the last day I will drive the 914 as a gasoline vehicle. With the busy-ness of life and the delivery delays from ElectroAutomotive, I don't know how long this will take. This will be an exciting process for sure. I feel grateful to have an army of supportive friends, OEVA members, and engineers at HP all backing me up.

Damn The Torpedos - Full Speed Ahead!

The Great Desulfation Experiment

Can one revive a mostly dead battery? Several internet sources say yes. Above is a picture of a heavily sulfated 8-volt golf-cart battery I acquired yesterday. It had a floating voltage of 7.85 when I got it and needed half a gallon of distilled water to fill it back up. Just off to the right of the battery I've attached the $250 "Cadillac of Desulfators" and it's merrily buzzing away along with a 1-amp trickle charger. At the end of today, I measured a charging voltage of 8.36 volts which should go up over time if the battery desulfates.

Don Denhardt, the national desulfation mastermind claims that this desulfation unit will restore one pound of sulfated battery per day. With the battery weighing in at about 70 pounds, this will take awhile, but I think it's worth trying to see if desulfators are worth it. Of course, the battery could have shorted plates and other problems that desulfation won't fix, but I'm going to give it a shot.

I still have two other 8-volt batteries (top picture) that I cleaned up today that also needed about half a gallon of water to fill each. They also started around 7.65 or 7.70 floating voltage so maybe I'll try to revive those too if this one shows promise. I suspect that I won't actually use these batteries in the 914 EV, but this research will help me understand battery technology better and perhaps give me some backup batteries in case one or two original cells go out. Who knows, I might even be able to revive bad cells in the battery pack if this works. Let's cross our fingers.

Getting Old Batteries and Fixing the VDO Clock

Whew, today was a long day. My friend Jonathan was in town and helped me go out to pick up some old, sulfated 8-volt batteries from Pacific NW Yamaha Golf Cars. Bob at NW Yamaha was great and sold me some old 8-volt batteries for $5 apiece. I'm going to use these to test out my 8-volt desulfator system to see if I can revive them. These US-Battery models are the same that are going into the electric car conversion. The one on the bench in the picture above was rather low and I had to add half a gallon of distilled water to fill it up.

Jonathan and I also headed back out to Camp914 to say HI to Craig and get some 914 counseling on how to jack up the car and remove the engine. He graciously let me borrow his special "12-point CV joint removal tool" (pictured above) so I could disconnect the engine from the rear axles more easily.

Jonathan and I also spent about an hour fixing the VDO clock which tends to die on most 914s. It looked like the entire clock gear mechanism was intact but the motor wasn't turning. After playing with my new $400 oscope, I reverse engineered the crystal-driven circuit on the board and found an open capacitor. The existing capacitor was rated to 16 volts and probably exceeded its expected operating life of ten years or so running continuously in the car. I replaced it with a much more robust tantalum capacitor rated at 35 volts and the clocks runs fine now. Craig at Camp914 was gracious enough to give me an accessory bulb socket so I could light up the clock too.

This will probably be my last weekend of joyriding in the car in its gasoline form since Alan at A & P will be swapping out the suspension next Thursday. Things are starting to move forward.