Change back to positive earth?

[johnny2rovers]

Recently acquired my first Series vehicle. '65 IIA currently neg earth w/alternator. It has been suggested to return to pos earth w/generator. I am trying to get to original. Current wiring is junk, so whatever the change, money is not the issue, something has to be done.

i would like your feedback, neg w/alternator or pos w/generator, a '65 and a good specimen.

[stomper]

What are you going to be using the vehicle for? Garage Queen, overland camping, joy rider? There is no real benefit to switching to positive earth except for originality if you are going for a concourse restoration that you won't be using. There is a reason people switch to negative earth, and an alternator.

[I Leak Oil]

Trying to make the truck "original" would be the only reason I can see to switch back to that setup. You can live well with both setups but one just limits what you can do with the electrical system a little more. OK a lot more.....

[luckyjoe]

You don't need positive earth to run a generator.

[I Leak Oil]

Out of curiosity who, in general, suggested changing it back and did they say why? A '65 is by no means a rare truck and having a - earth, alternator system isn't going to change it's value unless it's a true museum type restoration.
As Tom pointed out you can still run a generator on - earth...but then it's still not original.

[antichrist]

Yup, unless you're going for concours showing I can't think of a single reason to convert it back.
Ok, one reason, you like to remove a battery cable while the engine is running. That would be a reson to have a generator.

I'm also curious why the person said to covert it back to positive earth.

[SafeAirOne]

Out of curiosity who, in general, suggested changing it back and did they say why?

I'm going to guess that it was a fella with a last name of Lucas. Something about his ancestors being masters of reliable vehicular power distribution and this negative-ground thing was just a passing fad. Kept muttering "They'll be back grandpa. They'll be back."

[johnny2rovers]

I keep neckties too. They come back! I'll not say who, but a well known restorer. I just thought I would float it. Not going to do it.

[flighht2k5]

Yup, unless you're going for concours showing I can't think of a single reason to convert it back.
Ok, one reason, you like to remove a battery cable while the engine is running. That would be a reson to have a generator.

I'm also curious why the person said to covert it back to positive earth.

With an alternator you can take off a battery cable and the engine will still run.


Those who would give up essential liberty to purchase a little temporary safety deserve neither liberty nor safety.
Benjamin Franklin

[I Leak Oil]

I think generators are just far more tolerant of it than an alt., especially for any extended period of time.

[JimCT]

sorry no

over the road trucks that run up 100's of thousands of miles run alternators.

I think generators are just far more tolerant of it than an alt., especially for any extended period of time.

[SafeAirOne]

over the road trucks that run up 100's of thousands of miles run alternators.

He meant tolerant of suddenly removing all the electrical load by disconnecting the battery cable, a practice that can be harmful-to-deadly for alternators that don't have built-in load dump protection.

[antichrist]

With an alternator you can take off a battery cable and the engine will still run.

I didn't say it wouldn't run. At least until the alternator dies. So yes, you can remove it, but you have a high chance of frying the diodes. The alternator needs the battery to control the voltage. No battery and the voltage can spike to over 100v. That voltage is likely to fry the diodes, and other things on vehicles with computers.

[I Leak Oil]

over the road trucks that run up 100's of thousands of miles run alternators.

Without a battery connected???? What are you talking about?