Positive Ground

[steve_smith54]

There was another post regarding converting to a 12 volt system. It was also mentioned that the older Studebaker systems were not only 6 volt, as were all cars of that era, but also positive ground. First I assume that in using positive ground Studebaker was bucking the trend. I am not aware of other manufacturers using positive ground. Second, have people who have converted to a 12 volt system also converted to negative ground? I used to be a fair mechnaic in my younger days, but never did too much auto electrical work. Can someone enlighten me as to how a positive ground system works differently.

[DEEPNHOCK]

The entire automotive industry was 6 volt positive ground for decades, before the cost cutters figured out by increasing the voltage meant they could cut the wire size, thus saving some copper.
Converting to 12 volt is easy enough, but ask yourself a couple questions before you do it.
1) What isn't working correctly in 6 volt mode that 12 volt mode would solve?
2) What accessory do you want to add that is 12 volt?

Reason for asking is that if everything works ok on the 6 volt side, then you could add a 6v/12v battery and run the 12 volt accessory and still keep the 6 volt system. A good thing if your car/truck is a restoration.

A properly operating 6 volt system is plenty adequate on almost all Studebakers.

Converting to 12 volts is not hard. You will need to get a voltage reducer for the gas guage, wiper motor, and the radio (if equipped).
Several aftermarket places sell these (JC Whitney for one).The bulbs will all need to be changed to 12 volt. The starter doesn't care (as long as you don't keep cranking it too long. The amp guage doesn't care about voltage. The temp guage is mechanical. I'm sure others will add more detailed info...
Jeff[8D]

quote:Originally posted by steve_smith54

There was another post regarding converting to a 12 volt system. It was also mentioned that the older Studebaker systems were not only 6 volt, as were all cars of that era, but also positive ground. First I assume that in using positive ground Studebaker was bucking the trend. I am not aware of other manufacturers using positive ground. Second, have people who have converted to a 12 volt system also converted to negative ground? I used to be a fair mechnaic in my younger days, but never did too much auto electrical work. Can someone enlighten me as to how a positive ground system works differently.

DEEPNHOCK at Cox.net
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[gordr]

Steve,

Six volt Studebakers ('55 and prior) were positive ground, and 12 volt Studes ('56 onward) are negative ground, same as the rest of the North American cars. For years, British cars were 12 volt positive ground, up to the mid to late '60s, at least. There was a belief that having the ground positive made for less electrically induced body corrosion, at least that's what I remember being told.

As a bit of an aside, I have a '45 Studebaker US6 truck, and they were built negative ground if they were to have comms radios, and positive ground if they were not. Mine is negative ground.

Most people doing a 12 volt conversion on a six volt car will also convert to negative ground at the same time, so as to be able to use modern 12 volt radios.

Most of the electrical accessories on a Stude are not polarity-sensitive, and will work fine if the ground polarity is changed. The old vibrator radios WILL work on reversed ground, but it may not be good for them in the long run. Accessories ARE voltage-sensitive, however. The six-volt starter will crank faster, but will live a long time on 12 volts if you don't crank for long periods. Wipers, heater fan, and defroster fan will run fast, and speed control will be pretty ineffective. Best course for these is to replace with similar components from a later-model Studebaker, or spend a bunch of time finding a generic 12 volt motor at a parts house. Gauges need a regulated 6 volt source (actually about 6.5 would be best). You can build an IC voltage regulator, or buy pre-made regulators called "Runtz" out of a streetrod magazine. Light bulbs can simply be replaced with their 12 volt equivalents, bearing in mind that some Studes used a non-indexed 6 volt dual-filament bulb for stop/tail or park/turn applications. In this case one would have replace the socket shell to accept an 1157 bulb.

Frankly, I wouldn't bother converting a six volt Studebaker to 12 volts, unless I were doing it as full-on modified car. The six-volt system, properly maintained, is perfectly adequate. If you want to run a 12 volt stereo, you can obtain an inverter that will give you a 12 volt source, or you could simply run the stereo off a 12 volt gel cell, recharging it at home after a trip.

Gord Richmond, within Weasel range of the Alberta Badlands

[gotti210]

yeah its simple just follow everyone elses suggestions and you get it done i just converted my 50 about a month or two ago piece of cake

[N8N]

Gord,

the non-index base bulb is a 1158 (6V) bulb, you can replace it with a 1176 or 1376 12V bulb rather than go to the bother of changing out the sockets. Only thing is the parking lights will be 6 cp instead of 3 cp as they were stock, but then again on cars using these bulbs the parking lights are almost never used anyway (these are used on the front of my '55 coupe; the rears are standard index-base bulbs)

nate

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