Positive To Negative Ground... Will Gauge Still Work?

[beauishere]

Gentlemen,

My Dad reversed the ground on his 1938 Tudor Deluxe. Now the gauge reads discharge when it's charging. Is the solution as easy as just running the wire the other way on the gauge?

Thanks for any and all help.

 

[waterboychuck]

Since the gauge is now reading backward I would change it and see what happens.

 

[beauishere]

That's what we were thinkin' but I didn't want to do it and find out we shouldn't have.

 

[Mike in AZ]

should be all that's needed....reverse the direction the wire runs thru the ammeter....good luck....Mike

 

[makemc]

Yes thats all you need to do..that easy

 

[beauishere]

Thanks guys. We'll do it tomorrow. Nice to have an 'easy' one for a change.

 

[koates]

Why do you need to change it to neg ground?? Other problems arise like the voltage regulator contacts which are designed to operate on positive ground. They will burn out more quickly on negative ground as they are different metals in each contact pair. This is of course if you still have the original ford generator and voltage reg on your car. Has it now got an alternator ?

 

[garrisonm89@yahoo.com]

If the gauge is working backward then turn it around in the dash. I doubt it'll read any different but you won't be able to see it. And why do you need a gauge? If the vehicle is discharging, in time, it'll let you know.

 

[beauishere]

Why do you need to change it to neg ground?? Other problems arise like the voltage regulator contacts which are designed to operate on positive ground. They will burn out more quickly on negative ground as they are different metals in each contact pair. This is of course if you still have the original ford generator and voltage reg on your car. Has it now got an alternator ?

The car is stock. My Dad said he wanted the negative ground so that when it needed to be charged or jumped, whoever might be doing it, wouldn't mess it up. We had the voltage regulator rebuilt for the negative ground.

 

[beauishere]

If the gauge is working backward then turn it around in the dash. I doubt it'll read any different but you won't be able to see it. And why do you need a gauge? If the vehicle is discharging, in time, it'll let you know.

You can't turn that gauge around on a '38 unless you are talking about something inside the gauge. Just reversing the direction of the wire seems to be the consesus. I don't know about you, but I hate having anything on a car that doesn't work. Besides, this is my Dad's car and he wants the gauge to work.

I wasn't sure if you were kidding or not, but do you put gas in your car only after it runs out?

 

[garrisonm89@yahoo.com]

If the gauge is working backward then turn it around in the dash. I doubt it'll read any different but you won't be able to see it. And why do you need a gauge? If the vehicle is discharging, in time, it'll let you know.

You can't turn that gauge around on a '38 unless you are talking about something inside the gauge. Just reversing the direction of the wire seems to be the consesus. I don't know about you, but I hate having anything on a car that doesn't work. Besides, this is my Dad's car and he wants the gauge to work.

I wasn't sure if you were kidding or not, but do you put gas in your car only after it runs out?

I was just jerkin your chain.

 

[rotorwrench]

I never can figure out why someone wants to do so much work for no apparent gain. Now changing over to 12 volt might have some advantage for more modern electrics and compatibility issues but polarity change on a 6-volt system will just add more confusion down the road. An old fart like me would connect up to it wrong unless someone told me otherwise.

 

[Old Henry]

If the gauge is working backward then turn it around in the dash. I doubt it'll read any different but you won't be able to see it.

Or, you could just turn it upside down. Then it would read right and you could see it at the same time.

 

[Old Henry]

One downside to changing polarity is if you have a stock radio. The ******** inside will only work with positive ground. With negative ground you'd have to change the ******** inside the radio.

 

[296 V8]

You guys running positive ground better be careful …. don’t touch bumpers with a negative car.

 

[Jim in Wisconsin]

Touch bumpers? why- would that be like mater and anti-mater coming together and exploding into a fireball?
you wouldn't want to try jumping one battery to the other that way though.

 

[Old Henry]

Touch bumpers? why- would that be like mater and anti-mater coming together and exploding into a fireball?
you wouldn't want to try jumping one battery to the other that way though.

Or, is it like positive and negative poles on two very huge magnets that attract such that once they touch they can never be seperated.

 

[ford38v8]

I never can figure out why someone wants to do so much work for no apparent gain. Now changing over to 12 volt might have some advantage for more modern electrics and compatibility issues but polarity change on a 6-volt system will just add more confusion down the road. An old fart like me would connect up to it wrong unless someone told me otherwise.

Rotorwrench got it right. Your Dad's afraid that an idiot would get it wrong, but then, why have an idiot work on your car unsupervised anyway? (and what's to be gained by trying to confuse the experts?)

 

[Flat Ernie]

My Dad said he wanted the negative ground so that when it needed to be charged or jumped, whoever might be doing it, wouldn't mess it up.

As long as the cars aren't touching, it won't matter if you jump a positive ground car with a negative ground car...

If you've gone to negative ground, may as well go to 12V.