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6volt to 12 volt 39 buick


buicks39
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Sounds like you have a maintenance problem. There is nothing wrong with a 6V system. Make sure your connections are clean and your cable are right. A 6V system needs 0 gauge battery cables. Cable for a 12V system will not carry sufficient amperes. Remember Ohm's Law, half the voltage requires twice the amperage.

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I concur, you have something on your car requiring attention. These cars did start readily when they were new with 6 volts and there is no reason for conversion to 12 volts because of the problem you cited. Though the most obvious have been noted (12-volt or otherwise undersized cables, poor ground) you might also consider the starter motor condition, worn brushes, bearing/bushings worn, etc.

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starter was taken to a reputable rebuilder as with the generator and was told that they are fine and i would be wasting money to have them rebuilt.new interstate battery and the cables look fine and have been on the car since i got it and they seem to be original close to half inch in diameter.the only ground i see in the engine area is the one going to battery. thanks

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Warm cable is indicative of a problem. Either the cable has broken down and is heating up from resistance, or the cable terminal is loose or corroded, or there is a problem with the starter pulling too many amps. Back when I worked on trucks, if there was an electrical / starting problem I used to hunt down the problem by looking for a hot cable, such as you described.

By the way. it's easier to fix the problem than to switch to 12 volts and have to deal with all the changeover challenges (guages, lights, regulator, etc.). I have several cars with far-larger engines (525 cubic inches in one case) that start just fine on 6 volts. But they all have new, big cables and bright, clean terminal ends.

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the cable is about the size of my pinky.the cable is to the block.the connections are clean and new and i had the starter tested.im starting to think i need thicker cables.my thumb is the size of a heater hose ha ha thanks

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I kept my 38 Dodge as original, had my starter and generator rebuilt, new 6 volt cables, and put in a new voltage regulator. Also put in an Optima Battery (advertised to have 12 time the cranking power of a regular battery) and I am amazed at the power that turns over my car (6 cyl.). The electric guy who did my starter, etc., said the 6 volt systems worked fine when in top shape. I understand that the voltage regulator is often the problem with sticky points. You might check the voltage reg.

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Your cables seem to be wrong. Undersize cables will cause all the symptoms you describe. Most local auto parts stores will not have what you need, but can probably get it. The correct size is 0 gauge. It's heavy stuff. I bought an Optima 6V battery last year. It was money well spent. It does everything they claim it does. I'll let you know in a few more years about the longevity.

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If the cable is only as big as your pinky I think you found the problem. Modern cables just aren't heavy enough. Like someone else said, it should be as big as your thumb.

Yes, a welkding shop could make another cable for you.

Occasionally my 26 will give me trouble. The starter and generator are as new. So one day I started at the battery and cleaned each connection. When I got to the foot starter I even replaced it. Turned out to be where the cable from the foot starter where it connects to the starter. Now when it does it I simply loosen that nut and twist it back and forth a few times and then retighten it. I'm good to go for another month or two. Keep in mind I drive this car often.

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Good electrical supply stores will carry 1/0 AWG (one-ought, American Wire Gauge) copper WELDING WIRE. If they don't have 1/0 AWG, get 2/0 AWG (two-ought). Welding wire has 900 strands which makes it super flexible. It's costly (about $2.50/ft).

Measure how much you need, double the length (for the return gnd wire run), and have the electrical supply store crimp connectors on each end. When you run your ground wire, connect it to the block as close to the starter as you can. Cast iron has a higher resistance than copper, so you want to make the electrical path through your block as short as possible.

Any dirt or loose connection will cause arcing and heat. Too much heat will burn (and anneal) the copper wire, giving a dull orange-ish look. Overheated copper doesn't carry current very well. Six volts isn't very much push, so all your connections MUST be tight.

When you cut and strip welding wire, the tiny strands want to fray everywhere, especially if you shove the end into a crimp-lug. I usually take a few long strands of thin copper wire and wrap it around the fraying end (about 10 wraps). That keeps everything together until you clamp it, like in a battery post connector. Copper foil works well too, but you probably won't find that. Don't use aluminum foil.

Dave Dare

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There is an easy solution for 6-volt cables. Go to an auto supply in an industrial area of town, one that deals with alot of truck customers. The better shops will have big, heavy truck battery cables, typically in a half-dozen or more lengths. They will also have cable and cable ends so you can make your own to fit. I use these cables on my 6-volt cars.

Also, you could try going to a first-class battery shop (not an auto supply) and have them test the readings on your cables for resistance and voltage, and the voltage and amp draw of your starter.

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You're on the right track. There isn't a whole lot of difference between #1 and 1/0. If you can't find 1/0, #1 will do. Just make sure you change your ground and your hot wires with new welding wire.

Ground the body too, with #10 from the battery. That wire can be bare stranded copper wire from Home Depot. If they don't have #10, buy #8. I run mine from the battery all the way back to the trunk, clamping it along the way. If you need a good ground for tail lights, tap your copper ground wire. Especially with six volts, I got away from depending on spot welded sheet steel for my electrical bonding. All of a sudden, everything consistantly worked much better.

The reason your welding shop has #1, is because it makes great "stingers" (short lengths for guys who do arc welding). Rather than muscle the big heavy wire, welders just clamp-on with their stinger, and weld tirelessly all day.

I told you this because for short runs, #1 will carry loads much greater than their ratings. Duty cycle is the next consideration. Modern cars use #8-6AWG because they have a short run and nobody cranks for more than five seconds.

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Also make sure you have a ground strap from the frame to the engine. Those engines sit on rubber mounts and the closest ground connections are the fuel line, the throttle linkage, the ground wire from the generator to the voltage regulator. These weak grounds cause a lot of resistance also.

Also on the Buick the starter solinoid contacts can be arced and pitted causing a problem. If in doubt get a rebuilt one from Bobs Automobilia (805-434-2963).

The solinoid is not available new anymore and it is one big reason why you don't want to go 12v as the higher voltage will burn out the magnetic coil. Remember these solenoids have a send relay in them for the gas-pedal start.

Bill

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i put the heavier cables on today and turns over much faster how ever now i have no fuel in the fuel pump and even putting gas in the carb still wont fire.i drove the car in running 6 months ago and pulled and cleaned the tank and new fuel lines.is it possible the tank or lines are air bound.and yes i do need a ground from engine to frame,trying to find a nut to the block. thanks

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Buicks39, if you look at the carburator, you should see two wires attached to the starter switch on it.When you depress the accelerator pedal this switch connects the two wires, therefore completing the starting circuit to the solonoid. So if you connect a pushbutton switch, available at any auto parts store, to these two wires, it should work.

Ben

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when i rewired in the engine area those two wires from the carburator to the starter were connected together,how ever i took them apart and ran to seperate wires to the starter.that should not be a problem should it. thanks

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