[39DodgeD11]

can someone explain to me exactly what a positive ground battery system is? Does it mean the positive cable on the car goes to the negitive terminal on the battery and neg cable goes to positive terminal? Ive heard some talk about it since coming on here but i guess ive really never looked into it.

[mrpushbutton]

Positive ground means that the cable attached to the positive post on the battery (the big one) attaches to GROUND (the engine block, and a smaller braided strap to the chassis/body) on the other end and the NEGATIVE cable runs from the negitive post on the battery (smaller) goes to the starter solenoid, where that current is distributed to the starter when the solenoid is engaged, and the various tap-offs that terminate at the starter soleniod.
When you install the battery you still hook the large terminal to positive and the small terminal to negitive.
A lot of old cars are monkyed with re: positive ground because it hasn't been the standard for 50+ years and some folks just can't get their heads around the basic idea.
Trace where each cable is connected.

[Rusty_OToole]

Essentially it means the battery is installed "backwards". The positive terminal is the ground and the negative terminal is the live.

Many cars were set up this way. All Ford, Chrysler and Hudson cars and all English cars for a start.

It makes no difference at all to the car, except that certain parts are polarity sensitive such as the radio and the ammeter. These parts are made to get their power in a particular way. So just put the battery in the way the maker intended.

In the beginning when they first started making cars someone had to decide which way round to put the battery. Some chose one way, some the other.

There is only one good reason I know to prefer one over the other. If you notice, on your cars the positive terminal always gets nasty and corroded and covered in icky green guck first.

They figured if one cable was going to get all corroded and rot off it better be the ground because it was easiest and cheapest to replace. So they made the battery positive ground.

[John Vincent]

Don't forget about having to polarize the generator. When I got my DA the previous owner said that there was something wrong with the charging system, as it would read a discharge as the engine RPM was increased. Everything in the system checked out fine, polarized the generator, no more problem.

And not "all" Ford cars were positve ground. They built more than a few between 1919 and 1927 that were negative ground, the model T.

[John Vincent]

Don't forget about having to polarize the generator. When I got my DA the previous owner said that there was something wrong with the charging system, as it would read a discharge as the engine RPM was increased. Everything in the system checked out fine, polarized the generator, no more problem.

And not "all" Ford cars were positve ground. They built more than a few between 1919 and 1927 that were negative ground, the model T.

[elmo39]

not all English cars were either , i have owned Austins .Morris, Vauxhall and Landrovers and they were all neg ground . although there were some years of landrover that were positive ground.

[elmo39]

not all English cars were either , i have owned Austins .Morris, Vauxhall and Landrovers and they were all neg ground . although there were some years of landrover that were positive ground.

[imported_Bill-W]

Just as in North America, most of the British cars up through the 1950's were positive ground, although 12-volt was more common. And, just as in North America, Britain switched to negative ground.

To show how things changed over the years :

1930 : positive ground -
Auburn, Cadillac, Chrysler, DeSoto 8, Dodge, Erskine, Ford, Graham, Hupmobile, LaSalle, Nash (except 6-450), Packard, Studebaker, Willys, Willys-Knight

1930 : negative ground -
Buick, Chevrolet, DeSoto 6 (switched to positive 1931), Durant, Essex, Hudson (switched to positive 1934), Marquette, Nash (6-450), Oakland, Oldsmobile, Plymouth (switched to positive in 1931), Pontiac, Reo


1950 : positive ground -
Chrysler, Crosley, DeSoto, Dodge, Ford, Frazer, Hudson, Kaiser, Lincoln, Mercury, Meteor, Monarch, Nash, Packard, Plymouth, Studebaker, Plymouth
British - Austin, Ford, Hillman, Humber, Jaguar, MG, Morris, Riley, Rover, Standard, Sunbeam-Talbot, Triumph, Vauxhall

1950 : negative ground -
Buick, Cadillac, Chevrolet, Oldsmobile, Pontiac, Willys


1965 : positive ground -
Austin, Datsun, Envoy, Ford (GB), Hillman, Humber, Jaguar, MG, Morris, Riley, Rover, Singer, Sunbeam, Triumph, Vauxhall

1965 : negative ground -
Acadian, BMW, Buick, Cadillac, Checker, Chevrolet, Chrysler, Citroen, Dodge, Fiat, Ford, Ford (German), Honda, Isuzu, Imperial, Lincoln, Mercedes-Benz, Mercury, Meteor, NSU, Oldsmobile, Opel, Peugeot, Plymouth, Pontiac, Porsche, Rambler, Renault, Simca, Skoda, Studebaker, Toyota, Valiant, Volkswagen, Volvo


The last of the positive ground cars switched to negative -
Austin - started switch in 1971
Datsun - 1966
Envoy - 1967
Ford (GB) - 1967
Hillman - 1966
Humber - 1966
Jaguar - 1967 to 1969
MG - 1969
Morris - dropped
Riley - dropped
Rover - 1969
Singer - 1966
Sunbeam - 1966
Triumph - 1967
Vauxhall - 1967

Bill
Vancouver, BC

[imported_Bill-W]

Just as in North America, most of the British cars up through the 1950's were positive ground, although 12-volt was more common. And, just as in North America, Britain switched to negative ground.

To show how things changed over the years :

1930 : positive ground -
Auburn, Cadillac, Chrysler, DeSoto 8, Dodge, Erskine, Ford, Graham, Hupmobile, LaSalle, Nash (except 6-450), Packard, Studebaker, Willys, Willys-Knight

1930 : negative ground -
Buick, Chevrolet, DeSoto 6 (switched to positive 1931), Durant, Essex, Hudson (switched to positive 1934), Marquette, Nash (6-450), Oakland, Oldsmobile, Plymouth (switched to positive in 1931), Pontiac, Reo


1950 : positive ground -
Chrysler, Crosley, DeSoto, Dodge, Ford, Frazer, Hudson, Kaiser, Lincoln, Mercury, Meteor, Monarch, Nash, Packard, Plymouth, Studebaker, Plymouth
British - Austin, Ford, Hillman, Humber, Jaguar, MG, Morris, Riley, Rover, Standard, Sunbeam-Talbot, Triumph, Vauxhall

1950 : negative ground -
Buick, Cadillac, Chevrolet, Oldsmobile, Pontiac, Willys


1965 : positive ground -
Austin, Datsun, Envoy, Ford (GB), Hillman, Humber, Jaguar, MG, Morris, Riley, Rover, Singer, Sunbeam, Triumph, Vauxhall

1965 : negative ground -
Acadian, BMW, Buick, Cadillac, Checker, Chevrolet, Chrysler, Citroen, Dodge, Fiat, Ford, Ford (German), Honda, Isuzu, Imperial, Lincoln, Mercedes-Benz, Mercury, Meteor, NSU, Oldsmobile, Opel, Peugeot, Plymouth, Pontiac, Porsche, Rambler, Renault, Simca, Skoda, Studebaker, Toyota, Valiant, Volkswagen, Volvo


The last of the positive ground cars switched to negative -
Austin - started switch in 1971
Datsun - 1966
Envoy - 1967
Ford (GB) - 1967
Hillman - 1966
Humber - 1966
Jaguar - 1967 to 1969
MG - 1969
Morris - dropped
Riley - dropped
Rover - 1969
Singer - 1966
Sunbeam - 1966
Triumph - 1967
Vauxhall - 1967

Bill
Vancouver, BC

[imouttahere]

My '22 DB touring was definitely 12-volt negative ground from the factory. I looked it up in the instruction book.