Alternator upgrade frustrations...

Feeling my age time.dead horse
On generators -
They are built with permanent magnets in them. They will start your vehicle if you pull them far enough or roll it down a long enought hill with a dead or almost dead battery. They don't need a separate voltage source to work, the magnetism they all ready have will provide current and voltage needed to charge and start. They are also DC don't need to be rectified, just regulated. Alternators are AC and need to be rectified, along with being regulated.

The guy from the FLAPS probably hasn't ever seen a generator.R)

 

I saw this topic earlier and it got me to thinking, I didn't remember what the heck I did to wire up my alternator. (I guess my age is starting to creep up on me). Anyways, I went home and had a good look at my wiring harness. I still have it attached to the dash panel leaning on my garage wall, so I was able to see every bit of the harness from this perspective. Lets see if I can recall the wire routing.

Alternator pigtail, pos. #1, white wire is spliced into gray wire which feeds to the indicator lamp, which is grounded by a black wire. Red wire, pos. #2, is cut short and is terminated by a 1/4" ring terminal, which is connected to the output terminal of the alternator, that goes to the battery, or in my case of the Tuxedo Park, this wire goes to a junction on back of the light switch. (This got me too, this wire is preexisting). From there, a 10-12ga wire goes to the BAT. I have completely removed all unnecessary regulator wiring.

The same applies to my 1968 Chevy C10 with the exception that the tell-tale wire on it is brown.

I am not sure if this is of any help, but I hope it helps shed some light.

 

Are you sure the black wire connects the indicator lamp to ground? It should connect to the "on" position of the ignition switch. If it's grounded, the indicator lamp would light when the alternator is working.

 

It should not be grounded as said. To the on term of ign sw. I believe this gen lite wired to ground would cause a slow drain on the battery. At any rate, the #1 term at alt goes to one side of alt lite in dash and the other wire from alt lite goes to the on term of ign sw.

 

You are correct on that. When I looked at it last week I did not trace the black wire and assumed that it was ground. Upon further inspection as I stripped off the insulation to replace bad wires I had discovered that it did terminate at the ign. switch. Sorry for any confusion. I guess this would have been a common assumption, seeing that that wire was black, and black is typically a ground wire. Once again, my appologies for misleading you.

 

Thanks for confirming that. All's right with the world.

 

:dead horse::dead horse::dead horse:


Sorry to resurrect this thread but I felt it held the content I really needed and I thought this info could help if answered here.

Anyway, in reference to the above quote my engine will die if I remove the battery while running. Also, I have the indicator lamp hooked up to terminal #1 and it is on all the time when the engine is running. Is this correct or should the light only indicate when the alt. is not charging properly? I seem to have a slow drain somewhere possibly it is this light? I replaced this alternator today because I thought it was bad. I don't know now. My FLAPS checked it and it indicated it was bad. I checked the voltage at the alternator and it is a steady 12.49-12.5v at idle with the new alternator.

BTW I have nothing hooked to terminal #2 and this is how the jeep came to me. I assume this was working for the previous owner.

Any thoughts?

Thanks

Todd

 

You need to connect a wire from term #2 and connect it to the Bat term on back of alt along with that heavy red wire that goes to the battery +.

 

X2
:hurrican:

 

Is the light supposed to be on all the time?

 

No, the light should be on only when the alternator is not making electricity, or when it is making too much.

The other end of the light should be connected to switched +12V. If you apply 12 volts to the lamp while the engine is not running, this will provide some current to the field windings in the alternator. This current will cause the lamp to light, and will also produce the magnetic field the alternator needs.

Once the alternator is spinning, it will internally generate the current necessary to sustain this field. This will raise the voltage on pin 1 to 12V (nominally) and the lamp will extinguish. If the alternator does not generate this voltage, the lamp will light because the filed windings will still draw current through the lamp. Also, if the alternator generates too much voltage, the lamp will light indicating this opposite failure.

In reality, you might see a slight glow in the lamp even when all is OK, but it should not be nearly as bright as when the alternator is not spinning, and probably won't be visible unless you look closely.

As mentioned, terminal 2 should at least be connected to the BAT terminal on the alternator. Your measured voltage seems a bit low, which could be caused by terminal 2 not being connected.

If the light is on all the time, check that the other side of the light is connected to a switched +12V source. That is, it should connect to the IGN terminal on the ignition switch.

Does your engine still die when you disconnect the battery, even with the new alternator?

 

hmmm....I am going to do the same thing tomorrow; wiring up my alternator. Wish me luck!

 

Only when the engine is not running and the key is "on". Once you start it and begin to rev the engine, the lite should go out. Your volt meter chould read 14.2 to 14.8 (there abouts) at the battery if the alt is charging.

 

Nope 12.5 rock steady. I still haven't hooked up the #2 wire. I will repost when I do that. The light is on all the time but it could be that the light is hooked to the wrong spot. I am still trying to figure out how the PO drove it like it is.

Thanks

Todd

 

hooked up #2 light's out and steady at 15.1 volts.

Thanks

Todd

 

see if this helps they have a whole write up on one wire and three wire alts it helped me get my truck wired http://www.madelectrical.com/electricaltech/onewire-threewire.shtml and heres a diagram its a crude diagram but it works

 

ok so the "sensing wire" is going where? looks like a terminal block where the "BAT." on the alternator and switch and the positive for the battery are intersecting. My sensing wire is jumping right over to the stud on the alternator, and then the "RED" wire is going to the "BAT." on the switch. Should I run another wire from the positive terminal clamp on the battery to the "BAT." on the switch. (hope thats not too confusing)

what is a "bulkhead connector"? and can you ignore the Gen warning light and use an inline fuse and diode/resister that goes to the "IGN." on the switch? and then splice in the voltmeter into the wire that carries the inline fuse?

I thought something wen to the positive on the coil?

this is begining to make sense.

 

Actually you can delete the brown wire entirely. Not needed for the alternator to do it's thing. Just an indicator. A volt meter hooked up any where in the circuit will work just as well.
My Sixty just has the internal connections in the alternator and the heavy BAT wire connected to the wiring harness. There is an amp gauge on the dash it goes to, then to the bat connection on either the light switch or ignition switch. I would have to completely dismantle the wiring harness to be able to tell for sure.