Alternator upgrade frustrations...

I have read a whole bunch of threads on this, and it seems pretty simple, but my alternatro is not charging my battery. I switched out my generator and voltage reg. for a 3 wire 63 amp 10si alternator. The mounting was pretty simple, and I think I wired it right, but I have no juice.

Here is what I did...

Bat terminal on alternator to + on starter solenoid

The #2 spade terminal to the + on the starter solenoid

The + from the battery to the + on the starter solenoid

The bat terminal from the ignition goes the the battery +

The center (I think s) terminal from the ignition goes to the starter solenoid(on the right terminal)

At first I didnt have the 1 spade terminal from the alternator going anywhere, but I did send it to my amp indicator light, and still nothing...

Does the 1 spade terminal from the alternator need to be grounded?

I do have the ground from the alternator grounded...

What am I missing?

The battery terminals read a fluctuating voltage from around 3 volts to 12.volts when running, and is gradually drained when any power is used.

When running, if I turn the lights on, the battery drops quickly also, and would probably kill the engine if I let it go...

Sorry for the silly questions, but any help would be appreciated

Thanks

 

That wire from #1 on alt does go to the gen light. Does it come on when you turn on the key? Looks like you have it all ok but dont know about your ign sw wires.

 

for simplicities sake, I did not attach the wire from the 1 spade terminal...

i pulled everything off of the ignition except the positive batt wire from battery to batt on ignition, the wire on the center post of the ignition marked s that goes to the starter solenoid, and the ignition wire that goes to my coil...

after this simplified attempt to isolate everything, the jeep will jump off, run fine, but when I reattach the headligts, the headlights are dim and gradually dim down more and more until I turn them off(my voltage meter broke today, so I can't be more specific)

going tomorrow to take alternator(it is 4 days old) to flaps to have them bench test it, as I cannot see anything else(I had the battery tested 4 days ago) that could be wrong unless the battery test was innacurate

Any ideas about what is going on here?:?:?:?

 

I assume you've revved the engine to excite the alternator?
Posted via Mobile Device

 

yes...even drove it around town a bit, I imagin the rpms got up to at least 4500

 

Wouldn't be the first time a bad alternator came from FLAPS. Even when they test them on their machines.

Here's the diagram I used with my 10SI, sounds the same as what you've got already:

 

that was what I was going with, backed up by at least 5 other diagrams also...I removed everything elecrical from this simple arrangement, and I still have nothing...

Just to makes sure, the amp indicator lamp terminal can be empty, correct?

 

Mine has been empty for 2+ yrs, no problems.

 

"Wouldn't be the first time a bad alternator came from FLAPS. Even when they test them on their machines."

I'm thinking the alternator is bad, You should get 14 V with the engine running.

 

Unless I'm missing something, I think the problem is the (lack of a) connection to terminal 1. This terminal should not be left unconnected, nor should it be grounded. It should be connected to a current-limited switched +12V source.

Typically, this will be connected to one side of the indicator lamp. The other side of the indicator lamp should be connected to a switched +12V source (probably the IGN terminal on the ignition switch).

It's probably not a good idea to connect terminal 1 directly to the switched source. If you don't want to use an indicator lamp, you should probably put a resistor in series with it.

For a quick experiment, you could connect an indicator lamp between terminal 1 and the hot side of the ignition coil.

 

"Unless I'm missing something, I think the problem is the (lack of a) connection to terminal 1. "

I have 3 Jeeps that have been "upgraded" to 10 SI alternators, none of them have anything connected to the #1 terminal and all 3 worked fine. They can be hooked up with simply 1 wire from the + batt terminal on the battery from the + side of the solenoid to the batt terminal on the back of the alternator. They seem to work better with a jumper from the #2 terminal to the batt terminal on the alternator but the wire from the #1 terminal to the indicator lamp is optional

 

I believe that the #1 terminal has to be hooked to the indicator lamp in order to excite the alternator

 

getting conflicting info here...anybody else want to chime in?

 

http://www.madelectrical.com/electricaltech/onewire-threewire.shtml

More information here

 

Disclaimer: my JEEP has a generator, and I've resisted the temptation to mess with the alternator in any other vehicle, so my "knowledge" is derived from research (theory?) rather than experience.

As I understand it, you need to apply power to terminal 1 to get the alternator started. This provides the field current which magnetizes the rotor. Once the alternator is generating electricity, it provides its own power to maintain this field.

If an alternator works without a connection to terminal 1, it is probably because of residual magnetism in the rotor, which enables the alternator to generate enough power to "self-excite". Some alternators might have a higher residual magnetism than others, which could account for some alternators working without terminal 1 connected.

As I understand it, the "proper" way to wire a 3-wire alternator is to connect terminal 1 through an indicator lamp to switched power, and terminal 2 to a common tie point (such as the starter solenoid's battery terminal or the input terminal of a fuse block.) The regulator will strive to maintain the voltage on terminal 2 at the set voltage, so it can compensate for line losses. For this reason, connecting terminal 2 to the batt terminal will certainly work better than leaving it unconnected, but ideally it should be further "downline".

JMHO

 

This photo shows how my Jeep's are wired with the #2 terminal is jumpered to the Batt terminal. The reason this is confusing is there is confusing information out there. If you look at Jayhawkclints attachment it shows the #2 terminal jumpered to the Batt terminal, if the #1 terminal is jumpered the Battery will drain.

 

The way I interpret Jayhawkclint's diagram, terminal 2 is jumpered to the Batt terminal, as you indicate, but terminal 1 is connected through a resistor and indicator lamp to switched power. It's maybe not clear because the wire crosses over, but there's no connection indicated.

 

"the way I interpret Jayhawkclint's diagram, terminal 2 is jumpered to the Batt terminal, as you indicate, but terminal 1 is connected through a resistor and indicator lamp to switched power. "


That is correct but if you read carefully Mad's description in the link I posted it states the wire to the indicator lamp is optional and not required.

 

No, you don't. You can hook up terminal #1 to the gen lamp in order to get a "no charge" idiot light, but you don't have to. I'm not speaking in theory, this is personal experience on multiple GM engines. Sure, you might not get a "true" sense reading or whatever if you want to get into with the theory, but in practice, the batt stays charged plenty enough to start the jeep every time, run the headlights when it's dark, fire my HEI when I go down the road, etc. I get around a 13.8vdc charge at idle, IIRC, with no #1 hooked up.

 

I assume you mean this paragraph from the madelectrical site:

I interpret this to mean that the indicator light is optional (red text above), but the switched source is not (green text above). Again, when it works without this, it's probably due to residual magnetism.