Negative earth

[MuddyMachine]

My series 11 is still positive earth I was told to that you can chage it to negative earth  by turning the batt round connecting the earth to the negative, then tap the live cable 4 or 5 times onto the positive terminal. this changes the dynamo somehow and you now can fit an altenator. Making ithe vehicle negative earth.

Is this true? thought I would ask before I try as Im not upto speed when it comes to electrics

[mark.yellow.series.3]

no i dont think so,

i think there has to be modifcations to the alternator, and maybe some other things.

rich p should be along soon to help, hes just done his.

[Rich_P]

Yes I'm here.  Firstly, Mark... A Series Alternator never worked with positive earth. ;)  The dynamo is what can run on either positive or negative earth.

It's been a few months now since I got mine done, but this is what I remember.

Firstly, disconnect the battery.  Then you need to reverse the small wire connections on the coil (I think).  Reconnect the battery, but have it with the earth as negative.  Then feed a cable from the positive to the dynamo terminal and tap it three times.  Each time you should get a small spark.

Reconnect the battery fully and turn on the ignition... it should work unless I've missed some thing(s) out.

[Paul Woodward]

It's the field terminal (the small one) that you need to "flash" to re polarise the dynamo. Yes you do need to swap the coil terminals round.

[MuddyMachine]

Cheers gents,

Does this effect any of the electrics on the vehicle, like ignition, lights and dash stuff?

Can i connect other electrical items(eg spot) as I would on a normal neg earth vehicle?

Cheers again

[Rich_P]

Once you have reversed the polarity, you can connect equipment up as if it had always been negative earth.

In regards to fitting additional electrical equipment, please remember that the dynamo only produces enough power to keep the battery level the same when you have wipers, lights and heater going.  Add years of wire corrosion and the resistance increases, the result is that the dynamo's output is unlikely to be enough to recharge the battery with the standard equipment all at work, let alone with additionals.

[thermidorthelobster]

You'll need to turn the tyres around, otherwise the vehicle will run backwards.  :D

[MuddyMachine]

Im looking to re-wire the whole vehicle, would i be better fitting an altanator at the same time?

I dont want to drift any further away from its originality iff i can help it.

Cheers

[Rich_P]

Yes, fit an alternator, unless you want absolute spot on rivet counting originality.  An alternator gives a lot more flexibility, and makes jump starting a vehicle far easier too.

[MuddyMachine]

Cheers for the advice. :D

[blackbob]

fit an altenator much better charging :D

[S188]

About the only other thing not mentioned that is fussy about polarity are the power sockets on the dash (depending on what you run off them) if they still work (or a cigar lighter if ones fitted) as the +ve should have been grounded for +ve earth setup. Change them round to avoid acidently breaking something you plug in one day.  The only important resions to do a neg earth conversion is to fit an altinator or something like a radio as they usally only like -ve earth.

Also remember your battery posts aren't quite the same size so you can't just put the battery in the other way (easily).  Its worth sorting this out properly as one day you might forget when refitting the battery, I've done it before, landy wasn't happy!