Thread: Series 2 +pos to earth

Originally Posted by stevep

Hi all,

I have just bought a series 2 1958 SWB. I assume that it was positive to earth when it was built. It now has a holden 186 engine with an alternator but has NO battery. The engine looks like it has been in and running for a long time so the wiring had been sorted but I dont want to put the battery in the wrong way & blow it all up!!The holden alternator would have been neg to earth so does that mean it should be neg to earth?

How can I tell if it is neg or pos to earth???or which was round to put the battery?

thanks in advance

Steve

It will be negative earth, I don't think you'd find an alternator in Australia that wasn't negative earth. Check the output terminal of the alternator for sure, it should be marked B+ or similar.

As above. If it has an alternator, and certainly if it has a Holden alternator, it will be negative earth.

(If it has a generator, it may be either positive or negative earth (all Landrovers with generators were positive earth up to 1967) but is trivial to change)

John

thanks Guys for the comments. I am 99% sure its an alternator - short & silver-ish - not long & black like any generator I have seen & has what appears to be an external regulator (silver rectangular box). I will try it on the week end & see what happens.

regards
Steve

if its a holden its negative earth...

the best way of checking is the coil.

the top of the coil will be marked +ve and -ve (or just +/-) the side has the wiring that goes to the ignition switch will be opposite to which is earth on the battery (ie if the +ve goes to the key/ignition then its a -ve earth vehicle) the lead that goes down to the points on the dizzy will indicate the earth polarity (if the -ve pole goes to the points then its -ve earth)