25ACR Alternator Wiring

[dursleyman]

Thinking of putting the Lucas 25ACR on my TR7 to uprate the output but am a bit surprised when I looked at the wiring connection on the back.

Instead of the usual two big ones and one small, there are two small and only one big one, see the picture.


Big one is obviously the output but which of the others is the warning light? Is this sense wire I have heard about the other one and is it required?

What problems am I likely to ecnounter fitting it?

Russ

1980 TR7 Sprint DHC
Dursley
UK

[wedgewa]

Heater-only cars normally came with a 17ACR. According to my parts book, air conditioned cars could have either a 66 amp 20ACR or a 65 amp 25ACR. The 17 and 20 both use the same regulator so you might want to compare those connectors.