After adding a stereo to my car (1965 Valiant 170 slant 6 with power steering/no AC), the power to said stereo cuts off when the brake lights come on, and the RPM's fall under 1100. The stereo comes back on when the I let off the brakes, and RPM's come back up. I believe the alternator (original 35 amp) is not enough to power the stereo along with other electronics. So, I am wondering if a 45 amp alternator would make a difference? If so, the 45 amp has a two groove pulley versus the original that has a single groove pulley. Would the two groove pulley be compatible? Thanks.
Alternator question
- Thread starter klumppm1
- Start date
-
BigBlockMopar
BigBlockMember
Hardly.
Just upgrade to a modern small Nippondenso alternator, upgrade the wiring, install relays and all these 'old car' issues are gone.
Just upgrade to a modern small Nippondenso alternator, upgrade the wiring, install relays and all these 'old car' issues are gone.
BigBlockMopar
BigBlockMember
I also think the wiring to the stereo is of a too small gauge.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
- Messages
- 24,917
- Reaction score
- 12,267
What is the power consumption of your stereo?
What "other" electronics?
What kind of brakelight bulbs?
The point-type ignition system only draws maybe a couple of amps, and the brakelites even less, leaving plenty left over for a typical stereo. But that's only half of it; if the alternator died,the battery should power a typical stereo for hours.
I would check the amp-draw of the brakelites, there may be a short in that circuit.
in the meantime;
Crank the idle speed up, and don't step on the brake
What "other" electronics?
What kind of brakelight bulbs?
The point-type ignition system only draws maybe a couple of amps, and the brakelites even less, leaving plenty left over for a typical stereo. But that's only half of it; if the alternator died,the battery should power a typical stereo for hours.
I would check the amp-draw of the brakelites, there may be a short in that circuit.
in the meantime;
Crank the idle speed up, and don't step on the brake
Slantsix64
Well-Known Member
You need the Later alternator and voltage regulator, I always upgrade them because I always get the same problems you describe can't handle the voltage with the older style. If you still are rocking the points I would upgrade the ignition also at the same time. Two pulley or single will work. Just looks weird not using one of them
Slantsix64
Well-Known Member
Here you go.
I would think you had a weak charging system before stereo install. Most modern electronics need full 12 volts to operate. The light bulbs etc.., OEM to your car will function with low voltage, just pizz poorly. Assuming you still have the OEM gauge, does that needle twitch with turn signal operation? There's your sign.
If you have a voltage drop to regulator and alternators field ( that blue wire ), a higher amp alternator and/or different regulator wouldn't cure anything. Correct what you have first. Then if a higher output alternator is needed, it will work as it should.
@67Dart273 is better at diagnose/troubleshoot charging system than I.
If you have a voltage drop to regulator and alternators field ( that blue wire ), a higher amp alternator and/or different regulator wouldn't cure anything. Correct what you have first. Then if a higher output alternator is needed, it will work as it should.
@67Dart273 is better at diagnose/troubleshoot charging system than I.
-
