65 barracuda not charging PLZ help
Here is a mechanical voltage regulator (2 lug) and you can see the thing makes full boogie 17+ volts for milliseconds then opens to 0, then closes again (~20-200 Hz) to average out the regulation of the alternator power INPUT. The alternator needs a little exciter voltage to make ANY output power. The points style regulated the excitation + circuit, while Mopar switched to negative - regulation with the isolated field alternators and the electronic VR switching (at >2KHz), this was deemed safer as a dead short would not cause a runaway alternator. This provided the more stable output the new for Mopar electronic ignition needed. Pull the top off and watch it while probing and poking the various contacts and watching the DMM voltage while its running.
Here is a pretty good writeup on a mechanical regualtor function. If the alternator proves good (take it to Oreilly or autozone and have them test it for free) uise this and your DMM and start probing and thinking. It will add up and you
ll be all the wiser.
"...all of the old (actually ALL) of the alternator systems work the same way, when you put battery voltage to the field the alternator will put out full output-this can be 16+ volts. when you disconnect the battery from the field the alternator will put out 0 volts. voltage can be varied by how fast the points cycle in the regulator. the actual figure you are looking for with a CHARGED BATTERY is 13.8-14.2 volts. with a low battery the voltage will be considerably higher, right after start the voltage will be higher, the voltage is regulated by the the voltage input by the 3 out of 4 terminals on the voltage regulator and the time differential of open/closed points between the battery and field.
there are 2 common failure modes on a mechanical regulator"
1-a break in the fine armature wire that controlls the points, this will result in 0 charge.
2-pitted points in the regulator, this usually results in the points sticking and you will get a 16+ volt charge, or just erratic readings.
checking for a bad regulator, you do that indirectly:
1-fully charge the battery and hook a voltmeter to it, it should read 12.5-12.8 volts.
2- start the car and look at the voltage on the voltmeter, it should read 13.8 14.2 after stabalizing.
3-if it reads around 16, replace the voltage regulator.
4-if it reads 12, unplug the regulator and jump from the battery to the field terminal.
A-if the voltage jumps to around 16 replace the voltage regulator.
B-if the voltage stay at 12 replace the voltage regulator and alternator (you could just replace the voltage regulator but if the regulator was allowing the alternator to charge at 16 V and it burned out it will damage the new regulator.
these are just the rules for mechanical regulators and have no correlations to todays charging systems..."
Here is a mechanical voltage regulator (2 lug) and you can see the thing makes full boogie 17+ volts for milliseconds then opens to 0, then closes again (~20-200 Hz) to average out the regulation of the alternator power INPUT. The alternator needs a little exciter voltage to make ANY output power. The points style regulated the excitation + circuit, while Mopar switched to negative - regulation with the isolated field alternators and the electronic VR switching (at >2KHz), this was deemed safer as a dead short would not cause a runaway alternator. This provided the more stable output the new for Mopar electronic ignition needed. Pull the top off and watch it while probing and poking the various contacts and watching the DMM voltage while its running.
Here is a pretty good writeup on a mechanical regualtor function. If the alternator proves good (take it to Oreilly or autozone and have them test it for free) uise this and your DMM and start probing and thinking. It will add up and you
ll be all the wiser.
"...all of the old (actually ALL) of the alternator systems work the same way, when you put battery voltage to the field the alternator will put out full output-this can be 16+ volts. when you disconnect the battery from the field the alternator will put out 0 volts. voltage can be varied by how fast the points cycle in the regulator. the actual figure you are looking for with a CHARGED BATTERY is 13.8-14.2 volts. with a low battery the voltage will be considerably higher, right after start the voltage will be higher, the voltage is regulated by the the voltage input by the 3 out of 4 terminals on the voltage regulator and the time differential of open/closed points between the battery and field.
there are 2 common failure modes on a mechanical regulator"
1-a break in the fine armature wire that controlls the points, this will result in 0 charge.
2-pitted points in the regulator, this usually results in the points sticking and you will get a 16+ volt charge, or just erratic readings.
checking for a bad regulator, you do that indirectly:
1-fully charge the battery and hook a voltmeter to it, it should read 12.5-12.8 volts.
2- start the car and look at the voltage on the voltmeter, it should read 13.8 14.2 after stabalizing.
3-if it reads around 16, replace the voltage regulator.
4-if it reads 12, unplug the regulator and jump from the battery to the field terminal.
A-if the voltage jumps to around 16 replace the voltage regulator.
B-if the voltage stay at 12 replace the voltage regulator and alternator (you could just replace the voltage regulator but if the regulator was allowing the alternator to charge at 16 V and it burned out it will damage the new regulator.
these are just the rules for mechanical regulators and have no correlations to todays charging systems..."
