Change positive ground to negative ground

FredZ · Jun 12, 2014

Exactly what do I have to change to change my 2010 John deere from positive to negative ground. It is a twelve volt system.? thank you Fred

John T · Jun 12, 2014

In the event it has a Generator, it can charge fine at EITHER Polarity NOT a problem JUST BE SURE TO POLARIZE IT BEFORE START UP or you may damage the Voltage Regulator......If it had an alternator you cant swap battery polarity without some serious changing. Some voltage regulators work at either polarity, while some are labeled specific for POS or NEG ground. If yours isn't suited for Neg ground, its contacts may deteriorate.

In the event it had an ammeter, its leads would need swapped so it don't register bass ackwards.

For a coil ignition, the coil leads need swapped.

The starter is okay and still turns the same direction.

Of course, make the battery connection swap WELL DUH

If I missed anything the other fine gents can add more.......

John T

FredZ · Jun 12, 2014

I want to change it to negative ground so that I can put a chevy alternator on it.
So all I have to do is turn the battery around. and change the coil wires.? No change in the points or anything else.? Do I need to polarize when I put the alternator on.? thank you for all the help. I very much appreciate it. FredZ

wisbaker · Jun 12, 2014

You don't polarize alternators. Doing so tends to let all the magic smoke out of them. Don't ask me how I know this.

Steve@Advance · Jun 12, 2014

After reversing the coil leads, and the battery cables, that's all you'll do to the existing wiring.

There will need to be modifications to the wiring to connect the alternator though. Nothing difficult. If you're buying a kit, should get instructions and a plug you'll need for the alternator (depending on which alternator).

The hardest part is fabing a sufficient bracket and getting the pulley aligned and the correct width to match the belt. It's got to be right or the belt won't last, or the belt will slip and not charge properly.

FredZ · Jun 12, 2014

HI, how about if I use a one wire GM alternator. Where do I hook the one wire.? Making a bracket for the alternator should be no problem. It is the wiring that drives me crazy. will I need a button hooked up to excite the alternator? If so, where do I hook it.? Thanks to each and every one who has helped me. It is great advice. Fred

PJH · Jun 12, 2014

As John sez, "In the event it had an ammeter, its leads would need swapped so it don't register bass ackwards."

It will still charge correctly if the leads aren't reversed, but the ammeter will show a discharge and I promise that it will annoy you.

FredZ · Jun 12, 2014

It has an idiot light. Do the leads on that need to be reversed.? How about the gas gauge.? thank you Fred

rvirgil_KS · Jun 12, 2014

Do not get a one wire alternator, you will lose your charge indicator light.

On a three wire Delco alternator, BAT wire from the old regulator goes to the big stud on back of alternator

#2 pin on edge connector of alternator loops down to large stud on back.

On wire that went from charge indicator light to generator, connect generator end to #1 pin on alternator edge connector.

If it had an L terminal on the old regulator you can connect this to the big stud on back of alternator. This would be power source for light and ignition switches.

Steve@Advance · Jun 12, 2014

The gas guage will work as it is, so will the charge light. You're just going to move the charge light wire from the regulator to the #1 terminal on the alternator.

The alt you need is called a Delco 10SI. Any amperage will work, if you have air conditioner, go with a higher amp.

RWT · Jun 12, 2014

On an 1800 Oliver that I switched from positive to negative the electric water temp and fuel gauge had to be changed.

I naively thought I could switch the wires and that was a no go. It didn't ruin them. They just didn't work. In these there was a coil with a 'fixed' current and another that the sender varied.

RT (my 2 cents)

jeffcat · Jun 12, 2014

You may not to need all of the swap around jazz. Ask at a good repair shop about truck altinators. They are set up for positive ground and so you should be able to have your's set up for positive. Solves a whole bunch of problems.

John T · Jun 13, 2014

Yep, if installing a Neg ground alternator all you need is to turn the battery around and swap ammeter and ignition coil leads. You do NOT need to polarize the alternator.

John T

John T · Jun 13, 2014

You don't have to reverse leads on an idiot light but it needs wired correctly to suit that alternator. ON a Genny and VR it wired across the cutout relay but on say a 10SI family of 3 wire alternators it can be used in the circuit to excite the alternator plus limit current so the tractor doesnt run when you turn off Ignition. Like a diode or resistor (in a 3 wire alternator) it would wire in the excitation circuit from the Ign switch to the alternators small NO 1 terminal.

John T

rvirgil_KS · Jun 13, 2014

The vast overwhelming majority of alternators are negative ground.

The positive ground alternator would work fine until a person with the reasonable assumption that alternators are negative ground connects jumper cables from a negative ground source. The results could be hazzardous to someone's check book.

Change positive ground to negative ground

FredZ

New User

John T

Well-known Member

FredZ

New User

wisbaker

Well-known Member

Steve@Advance

Well-known Member

FredZ

New User

PJH

Well-known Member

FredZ

New User

rvirgil_KS

Well-known Member

Steve@Advance

Well-known Member

RWT

Member

jeffcat

Well-known Member

John T

Well-known Member

John T

Well-known Member

rvirgil_KS

Well-known Member

Similar threads