92 Volvo 240 Wiring Alternator internal VR instead of Ext VR

sparks894 · Post by **sparks894** » 17 Jul 2015, 14:11

The large red wire would go the battery. The small wire next to it would go to the instrument panel. The blue ground wire would go to the ground on the periphery of the alternator. What would I have to do to negate the external voltage regulator that was being used with the old alternator, which used an external voltage regulator?

93Regina · Post by **93Regina** » 17 Jul 2015, 21:34

sparks894 wrote:which used an external voltage regulator?

1992 240 Volvo - Bosch alternators are conventional 3-phase, self-rectifying type alternators. Bosch 110-amp alternators use 14 diodes. See Fig. 1. All alternators use 3 exciter diodes connected to stator windings. These diodes turn off the alternator indicator light and supply power to the voltage regulator while the engine is running. Bosch regulators are transistorized and integal with alternator.

sparks894 · Post by **sparks894** » 19 Jul 2015, 23:49

Can I just remove the external voltage regulator which is mounted on the side of the engine bay and install the 80 amp (80a) Bosch alternator which has an internal voltage regulator? Also, there is in addition to the red battery wire, blue ground wire, and the spade tipped, thin wire which goes to the instrument panel, a black wire which goes to a fitting imbeded in the engine block which seems to have something to do with oil. Can I just leave that black wire where it is?

93Regina · Post by **93Regina** » 20 Jul 2015, 08:00

sparks894 wrote:external voltage regulator?

Picture please...I have not heard of alternators having an external voltage regulator, in many years.

Yes, an external voltage regulator can be removed and replaced with alternator with internal regulator.

You can put a GM alternator on a Volvo.

sparks894 · Post by **sparks894** » 20 Jul 2015, 10:52

I apologize. What I thought is an external voltage regulator is something which is mounted on the inside wall of the fender. I removed the object and took it to the neighborhood auto parts store. The parts manager who had been working there for many years said he had never seen anything like it. I tried running a ground wire from the alternator case to the negative post of the battery. The voltage regulator wherever it is (it is not on the outside of the alternator) worked beautifully when I ran the motor. Thec battery charged now and when I increased the rpm the charging stayed at about 14.2 volts. I was happy as can be for about two hours then the charging stopped and the voltmeter inside the car stayed at 12 volts.

sparks894 · Post by **sparks894** » 20 Jul 2015, 18:12

Incidentally, I am going from a Denso alternator (the old one) to a Bosch alternator (the new one).

sparks894 · Post by **sparks894** » 22 Jul 2015, 12:44

Everything taken care of and working well now.