I've had another charging issue on my Pinto. Light comes on with ignition as normal, start the car, light goes dim but not out, rev the engine and light gets brighter. The voltmeter is showing 14V off load and about 13.5 with main lights on. I've checked it against the multimeter and it is the same as the voltmeter. If I take the revs up to around 3000 then the voltage rises to around 15V and if I ain't careful it will cook the battery.

So......I changed the regulator as the obvious culprit, and still the same. Just on the of-chance, I had 2 new regs so I fitted the second and......still faulty!!

I've checked the belt several times and am happy that it is tensioned OK.

Anyone got any ideas please? I'm getting rather P'd off with alternators on this damn car

Are the reg & the rectifier separate? - sounds like you have a diode gone down

Only really get worried about cooking the battery if the voltage rises above 15v
I take it is a 1970s Lucas ACR17 type
The first thing to check is that the lucar connectors are making clean good firm contact.

Beyond that you would need to strip the alternator and check the diodes and brushes out but personally I would just chop it in for a rebuilt unit.

Sounds like what happened to mine it was the diodes it was just easier for me to just get another alternator
Jacko