Learn me... positive ground?

Just a hypothetical question:

If one were to take a positive ground, zero electronics, generator equipped car, and accidentally switch the battery leads to negative ground... what would happen?

I know from experience that starters don't care, they spin in the same direction no matter what.

Probably burn up the gen's regulator in short order.

Same thing as when you switch negative grounds.

You can convert a positive ground Land Rover to negative ground in about 5 minutes. You just have to re-polarize (is that the word?) the alternator/generator. Everything else doesn't care.

http://www.expeditionlandrover.info/polarityConversion.htm

Keith wrote: You can convert a positive ground Land Rover to negative ground in about 5 minutes. You just have to re-polarize (is that the word?) the alternator/generator. Everything else doesn't care. http://www.expeditionlandrover.info/polarityConversion.htm

That's mostly true. You may need to swap leads on a coil if the spark suddenly seems weak. Otherwise, it's mostly a Brit thing...an affectation, if you will. The positive ground I mean. There isn't really anything other than some esoteric 'logical reasoning' that positive ground SHOULD be 'better' than negative. Most of the world considers negative grounds to be the way to go.

Well, the reason I ask... we have a '50 Stude in the shop right now, and it's SUPPOSED to be positive-ground, but the battery is connected negative-ground.

And it seems to be charging weakly and suffering from weak spark.

I suspect these issues are all related

With out doing a little re wiring wouldn't swapping the ground's on the battery result in the starter motor spinning backwards.

Why when you want to swap a fan from pusher to puller you swap the pos & neg resulting in the motor reversing direction?

What am I missing here?

It's the way starters are wound. They don't just have four poles like a fan motor, they have a dozen or more.

Try it next time you have a spare starter and jumper cables lying around. I wanted to spin a starter backwards, and found that I couldn't.

that is very interesting on starters...

I don't remember what year 'Merican Iron went negative ground. I think the English were a little late on it. My 47 Plymouth was positive ground, "6 to 8 Volts." You could put an 8 volt battery in it if you wanted to, to get better starting, like in the cold. Just fiddle the voltage regulator screw until it charged.

As for the Stoodie, I'd guess that someone converted it to negative ground. Any idea if it used to work and stopped working right or if someone just "converted" it and now it doesn't work? Is there an aftermarket radio, base cannon and 2KW amp in it? Or something with tubes?

I hooked up a 6v neg ground on a tractor this afternoon. Engine still turned the correct direction and nothing else seemed to care.

i changed a 60's John Deere 3020 tractor from positive ground to negative ground a few years ago.we only did this because the generator on it died and we decided to just put on a Delco 10SI alternator that was just laying around. the only thing we did was swap the leads on the battery and it works perfect. it even has more power now due to the alternator putting out 14.5 volts or so compared to the 12 that the generator out out before it died.. the gas gauge went kind of wonky after the swap, but that's a minor detail on a tractor that is mostly used for bringing a hay bale out to the cows every day..

When swapping polarity, electric motors with stator field coils will be OK, while those with permanant magnet stators will turn backwards. Until the availability of cheap powerful Alnico magnets, most automotive motors had stator windings.

You'd burn up all the wiring, especially under the dash. You'd probably burn your fingers trying to get the battery cable off, but it wojld be red hot and melted together with the battery post and then you'd probably run around screaming like a little girl. Or at least that's been my experience. BTDT with a Saab Sonnet.

Did it accidentally when replacing the battery. I'd never heard of a positive ground car before.