EA81 alternator wiring?

[aiiadict]

I can't find a diagram anywhere, and I've searched through the threads here with no luck...

 

EA81 alternator.

 

there are two wires. 1 thick white wire, 1 white/redstripe.

 

there are actually 3 wires, but two have been combined (by Previous owner)

 

2 conductor white connector (plug in)... this has a thick white wire coming off of it, and a thin white/redstripe

 

1 connector labeled BAT, with thick white wire coming off it (held on by nut, covered by rubber boot)

 

the thick white wire from the white connector is joined to the white wire coming from the BAT connector.

 

How do I wire this thing?

 

Is there an internal voltage regulator?

 

(links to wiring diagram would be appreciated!)

 

thanks,

 

Rich

[HatchDan]

Is the alternator on the car already? Mine has a thick black wire on the BAT terminal and your other two are correct at the plug-in. All three will disappear into the wiring harness, is this what you mean by the BAT wire being joined to the white plug-in wire? If your leads coming out of the wirirng harness match this discription you have it wired correctly. I guess the question is what do you want to wire the alternator into; are the wires you decribe coming off the alternator and going nowhere as in one pulled from a junkyard? Need some clarification.

[RavenTBK]

I dont have a diagram per se, but if you look into the USRM for my GM alternator swap, theres a couple pics with descriptions that might help you out and be what you're looking for.

 

On the flip side, the big wire BAT is the output terminal that goes to the battery.

 

On the plastic connector, the thick wire is the field sense wire, that energizes the alternator when the ignition is on.

 

The thin wire goes to the idiot light on the dash.

 

Depending on what you're trying to wire it into, you can just as easily hook the BAT stud directly to the battery, and jumper the thick wire from the connector to that stud, leaving the thin wire disconnected/taped off.

 

Hope this helps.

 

.rTBK

[aiiadict]

On the flip side, the big wire BAT is the output terminal that goes to the battery.

 

On the plastic connector, the thick wire is the field sense wire, that energizes the alternator when the ignition is on.

 

The thin wire goes to the idiot light on the dash.

 

 

Hi,

 

This is the information I was looking for... Thank you.

 

I don't understand why the alternator's "field sense" and "voltage output" terminals would be tied together. The subaru must have this wire running through a relay?

[aiiadict]

 

On the flip side, the big wire BAT is the output terminal that goes to the battery.

 

On the plastic connector, the thick wire is the field sense wire, that energizes the alternator when the ignition is on.

 

The thin wire goes to the idiot light on the dash.

 

Thanks!

 

the car (83gl) must have had a relay supplying +v to the combined "field sense" and batteryoutput wire. Otherwise the fieldsense would always have power and drain the battery with ign off.

 

So this alternator has an internal voltage regulator?

 

Rich

[aiiadict]

So this alternator has an internal voltage regulator?

 

I poked around in the forums some more and found that all subaru alternators after 81 have internal regulator.

 

BAT to + on battery (some say through fusible link)

thick wire (top of T on connector) to switched ignition

thin wire on white connector goes to idiot light circuit (a light bulb and a resistor, in the dash)

 

Rich

[Cougar]

The main output wire tied to the battery should also run through a fusible link to protect that wire since it is tied directly to the battery.