Hey folks; What's involved in switching to neg. grd for my '38 1/2 ton, 6V? Also, I've been jumped with our 12V car, real quick jolts, but would my 6V be any help in jumping another 12V??? Tks~JH

 

6V wont jump a 12V system. If you want to switch to negative ground I assume it's not a restoration, why don't you switch to 12V at the same time.

 

Switch the leads on the ignition coil, and you may have to re-polarize the generator. I am a little foggy on the polarizing thing, so see if you can find out more about it.

 

I'm with EricJ. It's a lot more of a job but going to 12v it a good idea. However it is not a small job. But if you do, your lighting would be vastly improved and the ignition would be better. Also you would have compatibility with newer vehicles. I would guess that you have vacuum wipers (?) but if they are electric it would require a new motor. New coil, and every light bulb would have to be changed. You may need a resistor for your instruments. I would go with a one wire alternator too. The starter would have to be changed too. If you have a 6v radio that would need a resistor.

Aw, that's way too much work! What was I thinking?

 

Ok~If I restore it and stay w/ 6V -pos. grd., can I get enuf power some way to add turn sig., heater, elec. wiper, dome lite?? I understand brighter lites need 12V or at least a strong 6V alt. Tks~JH

 

There is no reason you cannot add additional lighting.

Another possibility is that you could use a hybred system. You should change to neg ground if you do this. Add a small second 6v battery so that you can use 12v add ons because you would likely have a problem finding 6v pos ground accessories, like the wiper motor etc. It could be worked out.

 

You would not have any problem adding stuff to your 6 volt system, in addition to lighting like Bdox said.

For the wipers, all you would have to do is put an ad in the classifieds on this site and look for a 53-55 f 100 6 volt wiper motor. Most people change over to 12 volts, so I bet someone has one laying around they would sell you. I don't know about the mechanical hook-up, but I do know they are 6 volt positive ground. Now that I think about it, they must not be permanent magnet fields, since I ran my 6 volt positive ground wiper system on my 53 with a resistor and negative ground 12 volts. So just worry about getting a 6 volt motor.

And when you hook your accessories up, make sure you use fairly heavy wire. To do the same work as 12 volts, 6 volts has to carry twice the current. That's why the battery cables are so big(or they should be).

 

I've heard that some shops can rebuild the gen. to 12V in the same hsg. That way the original hsg. stays, then all the other things need to be changed or resistors added as mentioned before. Is there some reference to use that tells what gauges need res. and which don't, etc.??

 

Your gauges will definitey need a resistor if you go to 12v. Also if you go negative ground, you will have to reverse the wires on the back of your gauges and your coil. Hopefully the same shop can supply you with a 12v starter motor too. And plan on changine all your light bulbs as well.

 

I am not sure about the guage polarity. If both guage terminals are isolated from the metal of the dash, then you could simply reverse the wires if you had to. The guages do not draw much, so some of those small 3 terminal regulators will work, one for each guage. You can by these voltage reducers already made that bolt to each guage.

The 6 volt starter will be ok with the 12 volts, as long as you do not crank it for long periods of time. There are many 8n Ford tractors running around with 12 volt delco alternators and are still using the 6 volt starter. I have converted 2 over myself.

You may be able to re-wire the generator for 12 volts. Or it may be just an minor adjustment to the regulator instead of the generator, I am not sure on that one. It would be good to have a shop look at it for you.

P.S. Here is the guage voltage reducer. Go to www.speedwaymotors.com and type in 910-64101 in the search box. Other vendors sell them too.