external to internal regulator

[Uberoo]

My 81 hatch originally had an externally regulated alternator.While I was doing the EJ swap I chucked the externally regulator in the trash and wired up the EJ alternator to work independent of the original wiring.Anyway Right now I am re-doing some of that because I got tired of having to disconnect my battery otherwise it would go flat.

 

I am wondering what wires on the body side of the externally regulated plug need to be connected to each other so everything works as it should.

 

Thanks in advance.

[mikaleda]

I'm not sure what your asking, I just put an ej alt in my 80, the only wire you should need in the v/r harnness is the charge light wire. I wired my sense wire and charge wire straight to the battery with heavy gauge wire, if you want I can post some pics of what I did, my alt came from an impreza 2.2. The main wires you need hooked up are, the charge light wire, the sense wire, and the charge wire. You'll need to find out what wires are what on your alt. what did your engine come out of?

[Tsuru]

If you are losing battery charge when not running your have a shorted diode pack in your alternator.

The Diodes act twofold, as an A/C to D/C converter and as a one way valve preventing leak through to energize the alternator when not running.

 

OR

 

there is something remaining "on" when your key is on the O-F-F position, playing electron vampire with your battery.

my guess is the alternator remaining in a charged field coil state with the ignition switch off.

 

If I am incorrect in this please someone for goodness sake correct me as I have been spouting this ever since I can remember.

(Please be gentle, and sure to utilize small words. as I am slow of study these days. Being overfull of self affairs, my mind is likely to lose it)

 

quietly,

timothy

[Uberoo]

it was going flat because i wired the sense wire so it was constant hot.In the factory setup that wire is 12V switched.As I typed that I remembered what to do.Find the wire in the connector that has continutity to the orginal sense wire and find a wire that is 12V switched from the connector and slice them together.

[mikaleda]

My sense wire is constant hot, it should have direct connection to the battery to correctly adjust voltage. Your alt must be differant.

 

Edit: I was just thinking, the switched power isn't for the sense wire it's for the charge light wire, that is what activated the feild windings in the alt to make it charge, this needs to be hooked up through the charge light to work properly or you need to wire it to a switched hot with the correct resistance. If you wired your charge light wire straight to a 12v power source, that could cause the internal VR to burn out and creat a dead short that will kill you battery. I did that the first time I tried the swap in mine.

Edited May 7, 2013 by mikaleda

[Gloyale]

My sense wire is constant hot, it should have direct connection to the battery to correctly adjust voltage. Your alt must be differant.

 

Edit: I was just thinking, the switched power isn't for the sense wire it's for the charge light wire, that is what activated the feild windings in the alt to make it charge, this needs to be hooked up through the charge light to work properly or you need to wire it to a switched hot with the correct resistance. If you wired your charge light wire straight to a 12v power source, that could cause the internal VR to burn out and creat a dead short that will kill you battery. I did that the first time I tried the swap in mine.

 

No you are wrong Mikeleda.

 

The Charge wire and the sense wire on 90-94 EJ alts are 2 seperate circuits.

 

Charge wire is White/red in the EA cars.  IN an EJ swap you do not need to do anything except connect this White/red wire to the terminal that the B/W wire on the EJ alt used.  DO NOT give 12v to that line direectly.  If you measure voltage while disconnected  on that wire with key ON you get a bit less than 12v, but that is only because the 12v is passing through the lamp, trying to get back to ground.  That wire isn't actualy providing the sense function.  It does serve to excite but won't surfice for regulation. 

 

You need the sense wire that was originally yellow in the EJ cars.  On early alts this needs to be switched power.

The sense wire is indeed tied directly to the same yellow wire that supplies the ECU with IG. switched Voltage.

 

Later EJ alts eliminated this Yellow wire, and tied that function right into the Battery line.  I believe though that these alts are diesigned to function this way so they don't drain batteries like the early ones would if hooked up all the time.

Edited May 7, 2013 by Gloyale

[Uberoo]

thank you very much!

[Tsuru]

Thats it, as I recall the alternator in a kitplane I was messing about with had what I considered to be funky wiring at the time.

The field was switchable to effectively kill the alternator, it would still spin, but not charge.

I wasn't certain why that was until the owner of the plane explained it to me.

"It's an 'OH HECK, THERE IS AN ELECTRICAL LEAK' Switch. for when you do not want any more juice going to the electrical system and leaking all over they sky"

(I was about 12 at the time and it seemed plausible...for about 30 seconds!)

But it seemed a nifty idea, and a good theft deterrent if you don't mind walking the 15 to 50 miles to find your vehicle.

 

I like the coil to ground technique myself, (or coil output to seat cushion.)

 

many ways to get creative here.

 

Glad you sorted it!

 

quietly,

timothy

[mikaleda]

No you are wrong Mikeleda.

 

The Charge wire and the sense wire on 90-94 EJ alts are 2 seperate circuits.

 

Charge wire is White/red in the EA cars.  IN an EJ swap you do not need to do anything except connect this White/red wire to the terminal that the B/W wire on the EJ alt used.  DO NOT give 12v to that line direectly.  If you measure voltage while disconnected  on that wire with key ON you get a bit less than 12v, but that is only because the 12v is passing through the lamp, trying to get back to ground.  That wire isn't actualy providing the sense function.  It does serve to excite but won't surfice for regulation. 

 

You need the sense wire that was originally yellow in the EJ cars.  On early alts this needs to be switched power.

The sense wire is indeed tied directly to the same yellow wire that supplies the ECU with IG. switched Voltage.

 

Later EJ alts eliminated this Yellow wire, and tied that function right into the Battery line.  I believe though that these alts are diesigned to function this way so they don't drain batteries like the early ones would if hooked up all the time.

Well that must be why, mine is a 95. If you read my post I said connecting the charge light wire directly to 12v will fry your internal regulator, I know I did this the first time I tried it.

[Gloyale]

 

This is the layout for a 90-94 legacy.

 

Switched power on the yellow wire is for the sense wire. THIS should be hooked to IG.switched power or it can cause a drain.

 

Black/white wire is the Charge light. 2 seperate cicuits. The current coming through this line is Switches, but it's the negative side of the Charge light, so any voltage measured on that wire will be the "return" current to ground, and will go to zero when grounded illuminating the light. DO NOT HOOK 12v pos to the CHARGE post.

Edited May 13, 2013 by Gloyale

[mikaleda]

This is the layout for a 90-94 legacy.

Switched power on the yellow wire is for the sense wire. THIS should be hooked to IG.switched power or it can cause a drain.

Black/white wire is the Charge light. 2 seperate cicuits. The current coming through this line is Switches, but it's the negative side of the Charge light, so any voltage measured on that wire will be the "return" current to ground, and will go to zero when grounded illuminating the light. DO NOT HOOK 12v pos to the CHARGE post.

If you read my last post I said that I had an alt out of a 95 so it is different, the way I have mine hooked up IS correct my alt works perfectly, BUT that is a differant alt.

 

Gloyal, please do not take this personal, but you really need to read a little more thoroughly before you comment. I'm sure you are correct about 90-94 alts, I do not know about those in particular, but I do know how my 95 alt works.

Edited May 13, 2013 by mikaleda

[Gloyale]

If you read my last post I said that I had an alt out of a 95 so it is different, the way I have mine hooked up IS correct my alt works perfectly, BUT that is a differant alt.

 

Gloyal, please do not take this personal, but you really need to read a little more thoroughly before you comment. I'm sure you are correct about 90-94 alts, I do not know about those in particular, but I do know how my 95 alt works.

Sorry I missed that I had already posted this info. 

 

And you are correct, in 95+ Alts the sense wire is jumpered directly to the battery, and not tied to the IG. circuit.

 

Still though, the cahrge wire is not the sense wire and it isn't switched 12v.  It's the ground leg of the charge light and will only measure voltage until the ALT grounds it when Key on/eng off.  Start the car, voltage goes high on that post and turns off the light. 

[mikaleda]

Sorry I missed that I had already posted this info. 

 

And you are correct, in 95+ Alts the sense wire is jumpered directly to the battery, and not tied to the IG. circuit.

 

Still though, the cahrge wire is not the sense wire and it isn't switched 12v.  It's the ground leg of the charge light and will only measure voltage until the ALT grounds it when Key on/eng off.  Start the car, voltage goes high on that post and turns off the light. 

Yes I agree, easier done than said I know the charge wire doesn't sense voltage and isn't switched 12v I just reread my info and I didn't describe it very well, sorry for the confusion.

[Tsuru]

Hats off gentlemen, to single wire Delco alternators

Long may they spin...

I wasn't excluding the ladies in that statement. For long standing etiquette establishes that they are not required to remove their hats (bonnets if you will) for solemn and somber remembrances, but times being as they are, and all things being equal, they may indeed participate in the removing of hats for to remember the simple greatness of the AC Delco internally regulated, self exciting, single wire alternators if they should choose to do so. 

 

spin on little alternator...spin on....

 

 

(heehee)

timothy

[Uberoo]

single wire alts suck for low speed charging.If your idling with a single wire alt with your lights on the car will go flat because a single wire alt doesn't start charging until 1500-2000 rpm.

[mikaleda]

Single wire alts are best in tractors wich stay at a steady rpm range higher than a cars idle

Edited May 18, 2013 by mikaleda

[Tsuru]

And yet again I am reminded how I am ignorant in many things. I used them on marine applications, small high rev fours mostly, so my experience with them is rather limited...it doesn't change my love for them though. I like simple.

I did have an electronics savvy friend of mine modify one for his own use, and put it in his vehicle (1960s Ford Falcon Futura) and it did fine, but like I said, he modified it somehow, I never asked. He was Missile Tech at Vandenberg AFB, There was much I didn't ask him...

 

I am now that much smarter on single wire alternators...

(yay! thanks!)

 

Wow what a dolt I can be!

 

heehee,

timothy