coverted to negative earth

[craig12]

my 1953 morris has been coverted to negative earth , why would this have been done is there any advantage ? I am thinking of converting it back , the car is running and all appears well but I notice the fuel gauge is disconnected ., has anyone else felt the need to do this .

[mike.perry]

It has probably been converted so that modern neg earth components can be used. There is also less electrolytic action with neg earth

[tysonn]

Maybe last owner had a stereo fitted?

[craig12]

I will put my avo on the wire to the fuel sensor unit but I guess hes got a feed now on this wire and that's why its disconnected , can I alter this unit ? every thing else works but unless the dynamo polarity has been reversed im guessing it wont charge , will look into this to see just how far he went with this alteration , I would really like to keep standard , less electrolytic action , this is interesting could you explain this in more detail please

[mike.perry]

With a pos earth car there seems to be more deposits on the points and other components than with neg earth cars. This has something to do it the direction of travel of the electrodes.
Ok I have dug myself a hole and it is time to stop digging. Perhaps someone else can expain it a bit more scientifically

[tysonn]

Plenty on Google about it.Just look it up.

[craig12]

so i see , other than the radio (i can get round this as im fitting a ipod doc) i see no reson to do this , so i think i will go back to standard (also saves the fuel sender unit problem) just wonderd why it was done in the first place

[Boomlander]

I was told by an even older-timer that a positive earth system produced a more consistent and even spark at the plugs at the expense of some slight increase in electrolytic action between the battery and the body.......????????
Jethro is Positive Earth as the creator intended and has an isolator on the battery so it is disconnected when not in use but of course to add modern accessories like a radio or sat nav you would need to convert to negative Earth.

[craig12]

the sat nav maybe a problem as i do use one a lot

[tysonn]

Not really its all encased in plastic.No risk of shorting against the body.