Voltage problems, cutting out when hot
Sorry I missed or forgot you said in the very first post that its a 1998 magnum 360 with Denso alternator and serpentine belt, etc.
Ripple: Each winding in the alternator is produces alternating current. Looking at voltage vs. time on an osciliscope, it looks like a voltage wave. There's three (or more) windings producing overlapping waves. So for all practical purposes the voltage looks steady. But there is a slight fluctuation or ripple.
Flickering or pulstating Headlights
I don't if any Denso alternators are internally regulated. Certainly some are not. Should be able to look that up on an on line catalog.
I've not dealt with them myself. Slightly concerned that the field current draw is higher than the VR can handle. I may be concerned about nothing.
FWIW. Squareback draw
Notice in the alternator specs, the factory test is for current output at 1250 rpm. This is tested by putting an electrical load on the system and regulating the voltage.
Current is measured at the load (placed across the battery) or at the alternator.
5 amps needed for the field and ignition branch off before the battery.
I don't know what the parts store test results are really telling us.
For the time being, prob safe to assume your alternator is working fine.
I've had the same type of question before - its not specific to your experience.
let me dig it out. here it is. This is an internally regulated Delco 12SI alternator. Ripple allowance is similar. Seems high to me, but in reality functions OK.
Here's a test result for a similar SI-12 that is understandable.
Getting back to Chrysler type alternators.
This is for a revised squareback (late 70s until ?)
Ripple is .23 amps,
Current was tested at 13.2 Volts (so it will show higher current output than a factory spec)
Field current draw was 6.8 amps! That seems high compared to the older alternators - but I don't know if it was tested the same way.
Not sure how helpful any of this is to your current situation. Just some background.
Sorry I missed or forgot you said in the very first post that its a 1998 magnum 360 with Denso alternator and serpentine belt, etc.
Ripple: Each winding in the alternator is produces alternating current. Looking at voltage vs. time on an osciliscope, it looks like a voltage wave. There's three (or more) windings producing overlapping waves. So for all practical purposes the voltage looks steady. But there is a slight fluctuation or ripple.
Flickering or pulstating Headlights
I don't if any Denso alternators are internally regulated. Certainly some are not. Should be able to look that up on an on line catalog.
I've not dealt with them myself. Slightly concerned that the field current draw is higher than the VR can handle. I may be concerned about nothing.
FWIW. Squareback draw
Notice in the alternator specs, the factory test is for current output at 1250 rpm. This is tested by putting an electrical load on the system and regulating the voltage.
Current is measured at the load (placed across the battery) or at the alternator.
5 amps needed for the field and ignition branch off before the battery.
I don't know what the parts store test results are really telling us.
For the time being, prob safe to assume your alternator is working fine.
I've had the same type of question before - its not specific to your experience.
let me dig it out. here it is. This is an internally regulated Delco 12SI alternator. Ripple allowance is similar. Seems high to me, but in reality functions OK.
Here's a test result for a similar SI-12 that is understandable.
Getting back to Chrysler type alternators.
This is for a revised squareback (late 70s until ?)
Ripple is .23 amps,
Current was tested at 13.2 Volts (so it will show higher current output than a factory spec)
Field current draw was 6.8 amps! That seems high compared to the older alternators - but I don't know if it was tested the same way.
Not sure how helpful any of this is to your current situation. Just some background.