Positive earth to negative earth conversion

[GeoffHickson]

G'day all.

I have a S2 shorty with a Holden motor and will be converting to back to a original 2.25lt donk which has positive earth and a generator. Landy at present has neg earth & alternator and would like to keep it hat way. Not to sure what I need to do/change on the 2.25 lt motor (coil wires etc). Any advice would be great.

Cheers Geoff

[JDNSW]

Essentially, the only change you need is to get a suitable alternator and mounting for the 2.25. In theory you need to reverse the coil leads, but it will almost certainly make no detectable difference.

Obviously, the rest of the wiring is working with negative earth, but in fact the only wiring change required when converting from positive to negative earth is to reverse the connections to the ammeter (if retaining the originally positive earth generator, you need to reverse the remnant magnetism in it). The fuel gauge on the positive earth Series Landrovers does not worry about polarity.

Presumably the wiring has been modified to suit the existing alternator, but if the current alternator does not suit the mounting on the 2.25 engine (best to simply use brackets from a S3) and you change alternator, you need to be aware that the required wiring may need to be slightly different.

John

[GeoffHickson]

Thanks John, I was hoping it was going to be that simple, but I wasn't sure. I can't seem to get my head around positive earth.

Cheers Geoff

[JDNSW]

Just one other bit of information to add to my post above - if anyone is worrying about whether the starter needs a particular polarity, the answer is - starters work exactly the same on either polarity.

John