changing a cars polarity from posotive to negative earth?

Question

ford prefect 107e with posotive earth requires changing to negative earth

Answer 1

Hi. This is a tricky job because the polarity of some electrical devices within the car would also have to be changed.

Answer 2

Car electrical systems are based on Direct current(D.C), which has a positive and negative flow of current as opposed to A.C., or alternate current.In a positive earth system the positive terminal of the battery is connected to earth and all other devices like the starter motor, dynamo, distributor,induction coil and others are matched to the battery polarity. If you want to change the positive earth to negative, you need to change the polarity of the other electrical equipments inside the car with the help of an automobile electrician. Otherwise by simply connecting the negative terminal of battery to earth, will result in burn out of some of the devices.

Answer 3

Not that difficult. You will have a dynamo and you can change the polarity of that by just touching the field wire on the positive of the battery. You will have to switch the wiring on the clock and possibly the fuel gauge. It is a basic car and I think everything else will work. Obviously connect the battery negative earth

Answer 4

Do you mean the ground? As in batteries and electrical systems? I would buy or go to the library and find a manual for your car..they tell how to do most of the things you might need to do as far as car maintenance. I think your question would be better answered in another category. Another idea is to be a caller on Car Talk...they are really good (and funny) and answer calls from people with car problems and seem to be very helpful. I would say just swap the red and the black..but since I only have a vague idea of what you're talking about..I don't want to give what might not be appropriate advice.

Answer 5

It has been years since i did that job many times myself on my early hillman imps and mini's. What u have to do is any equipment that is positive earth u will have to IsOLATE THEM FROM THE CARS METAL BODY, obviously u turn the battery around and only connect the earth terminal to negative and with a piece of wire long enough to reach from the battery to the dynamo u connect the wire to the positive live terminal of the battery and the other end after disconnecting both wires to back of dynamo there is one large and one small terminal, with the live wireu touch the large terminal gently 3 or 4 times it will cause a little spark, thats the dynamo's polarity changed to negative earth, i am pretty sure all u do then is connect up dynamo wires and live wire to battery, mi am pretty sure i have covered it all but please double check incase, or if u want try and connect the live positive terminal to battery only by hand to stsrt with, u will get a little spark but if spark is more than little stop and seek help before carrying on. If ball goes well, either fit a modern radio or isolate ur radio from body using wood or plastic console run both wires direct to battery putting wires on correctly ie positive earth if using origional radio. re when connecting live wire to battery just offer ti up to battery but dont bolt it up till u know its ok, u will get a little spark if its ok but it will spark ablot if wrong so stop trying right away.

Please4 let me know how you get on. Jimmy Essex england

Answer 6

The polarity of the battery makes no difference. That has already been done .

Answer 7

Does the car have a dynamo? If so, you may need to upgrade that to an alternator but apart from that it should be fine.

Answer 8

turn the battery around

Answer 9

depens