Hi guys, I'm trying to fit an alternator and could do with some help regarding the wiring.

The van is a 78 Bedford CF. I've removed the old alternator (lucas) and have a new one (delco) to fit. I have a wiring diagram and know which colour wire goes where, but there seems to be a terminal missing.

The big terminals are for the battery charging & earth. Then there's 3 small terminals in the L shaped bit. One is for the thin brown wire (battery sensing), which is fine. Then in the diagram there's 2 terminals for the brown/yellow wire (warning lamp) with a loop connecting the 2 (3 wires labeled '3', two of them are just wired to each other), then going back to the warning lamp. Except on my alternator one of these terminals is missing...

So... is the second terminal & loop essential to function? If it is, why isn't it integral to the alternator?

From comparing the alternator to the diagram and the positioning of the wires, it APPEARS that the missing terminal would be attached to the casing of the aternator (but not sure), if this is the case could I just earth it elsewhere on the casing?


Wiring diagram (the left one)
http://i1006.photobucket.com/albums/af187/frog_dude/delcoalternatorwiring.jpg

My alternator
http://i1006.photobucket.com/albums/af187/frog_dude/DSCF2385.jpg

You are playing with fire. Since it's not an exact match, you run the risk of seriously damaging your electrical system.

Instead, why not rebuild the original alternator, by installing new bearings, brushes, and regulator? This is less risky and cheaper ($20 or less).

The one I'm fitting is the original part for the van, the Lucas one that had been previously fitted was a replacement and the wiring had been butchered to fit.

And being 34 years old, parts are not that easily available. You have to go with what you can get.