what is this wire for?

[Thomas77GR]

It is an old (original) wire, it comes from the starter and is in the same bundle where the blue/white wire goes to the alternator (fusible link). There is already a red cable feed to the alternator from the starter so it's got me thinking. My battery ran empty the other day so could this be an issue with the charging circuit? It is for an A series CIH. thanks

Edited June 10, 2022 by Thomas77GR

[cam.in.head]

hard to tell but yes it looks like the main wire between the alternator output and the battery positive ( i assume 'a's are negative earth ?) 

there should be a small link between the alernator side terminal and the main terminal.the other blue/ white goes to the dash charging light.

also an earth lower down on the alternator casing to the engine bracket.

[Thomas77GR]

Hi, thanks for your reply, does not seem to be the cable that connects on the battery positive as when I attempt to do that, it pulls tight on the other thin wire which attaches to the side of the alternator. Having said that there is no direct cable that comes back from the alternator to the battery, there is a positive cable from the battery to the solenoid starter, a positive from the solenoid to the alternator. Random thought, I used to have air horns fitted a while back, could this be the positive feed to the air horns? Will see if I can get better pictures. A simplified wiring diagram between battery, starter and alternator would be helpful. Yes it's a negative earth standard A series. My voltage regulator behind the dash is goosed too. 

[Jessopia74]

I would have said alternator too, but looking at your wiring there, you already have a link. Looks like it was for relay etc. poss 6v coil system as it might be coming off the starter shunt coil motor side (lower bolt lug)
Either way, get it insulated or disconnected, along with the 2 terminals floating about. Don’t want a shirt to earth and potential fire.

[cam.in.head]

if as jess says there already is a wire from the main battery positive on the starter then providing the alternator is ok and otherwise wired ok ( earth and dash light) then it should be working. 

hard to tell from the pic realy but the red wire taped up in the loom would have been the proper wire originally ,the black wire looks like it was added for some reason. 

Edited June 16, 2022 by cam.in.head