8n alternator help

[Eman85]

Plenty of info on how to disassemble and test these alternators. Easy to take apart, no special tools past a DVOM and a toothpick or paperclip. Just mark the cases and pay attention to how it's clocked. Easy enough to go with a junkyard alt. and wire it as a 3 wire using a bulb or a diode.

 

[Hobo,NC]

(quoted from post at 21:24:05 06/23/23) Plenty of info on how to disassemble and test these alternators. Easy to take apart, no special tools past a DVOM and a toothpick or paperclip. Just mark the cases and pay attention to how it's clocked. Easy enough to go with a junkyard alt. and wire it as a 3 wire using a bulb or a diode.

We can get way off topic on this.

I prefer a analogy meter for this cuzz I like to see the needle on the meter sweep : ) You need a small battery charger to check the rotor and a soldiering gun to solder the lugs on the stator leads just cuzz you can.

This is why in the 70/80's you could make good money running a repair shop. If you got slow you could store labor by rebuilding starters, alternators, transmissions and engines. When you got busy you had your labor stored on a shelf. You would go broke doing that today and end up stuck with your stored labor/parts.

 

[DaveZ (CA us)]

Just knowing that the voltage changes does not tell you what is going on. Electrical circuits need a combination of volts and amps to do work. You know how the voltage is changing, but nothing about what the amps are doing. If the amps are lower than they are supposed to be, there may not be enough to power the system.

Normally in an electrical circuit, if a load (like charging a battery) is placed in a circuit, the volts will drop and the amps will rise. In this case as the battery charges, the amps will slowly decrease and the voltage will slowly increase.

But if the alternator or the battery is weak, we may never get to a good voltage. Or perhaps there is something else in the circuit that is draining the power? If there is another drain in the circuit, why is it only draining when the battery connected?

You need to know how many amps the alternator is producing when you connect the battery into the circuit. Is the alternator producing its rated amps?

As suggested before, if you leave the battery connected with the engine running, does the battery voltage climb to a higher level after 20 minutes? That would suggest that the alternator is trying to charge the battery.

Your comment about the alternator making more noise when the battery is in the circuit suggests that the alternator may be producing more amps, but is it enough to charge the battery?

Unfortunately, all I have is questions.