Bosch alternator

[Yuxi]

Hi all,

I have an old Bosch alternator on the kit car (Sierra Pinto engine). It was charging the battery well but the charge light came on once it was hot, the more load the brighter the light. Even with the light shining brightly there was 14.4v at the battery.

I replaced the brush/voltage regulator pack thinking this would solve the issue but it made no difference.

Measuring voltages at the alternator I have 14.5v max on the big wire at anything over tickover but 20v plus on the wire to the light, hence it is coming on (20v - battery v lights lamp)

Can the thing that controls this voltage be replaced?

Thanks

Steve