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EJ alternator on a EA82?

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can it be done?

is the EJ alternator internally regulated?

does anyone have a pin out for the plug on this alternator?

 

just throwing that out there.

 

thanks in advance

 

Ben

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Probably not worth trying to make it work.

 

You can put in an XT6 or a Nissan Maxima? Alternator if you want more output and they are much less work, and if you dig a bit, you can probably find posts showing how to install and wire them properly.

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Probably not worth trying to make it work.

 

You can put in an XT6 or a Nissan Maxima? Alternator if you want more output and they are much less work, and if you dig a bit, you can probably find posts showing how to install and wire them properly.

 

I read the posts about those options, I was just curious if anyone had done this.

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I have an EJ22 with alternator on the stand at the moment. I also have a Maxima alt on my EA81. I took measurements of both and it looks like either would bolt right up. I think it would just be a matter of sorting out the wiring.

 

Someone is working on it here I think.

AU Subaru

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EJ alternators are not all the same, electrically.

 

That said, wiring them in is not that hard. Wiring ANY internally regulated alternator is quite simple.

 

 

So, it's "just" the case of building a bracket and finding/making a pulley. good luck :-\

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when i first swapped the EJ into my brumby i tried to use the EJ alternator.....it boiled my battery....the EJ alt requires a signal from the EJ ECU to tell it how much to charge....if it doesn't get that signal it charges at 16.6V:eek:....and your battery boils its head off:mad:

 

i swapped the pully off the EJ alt onto the EA alt ( and had to shorten the spacer behind the pully to bring the engine and alternator pully into alignment)

 

i've been keeping an eye out for a nissan 90 or 100 amp alt but no luck yet

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when i first swapped the EJ into my brumby i tried to use the EJ alternator.....it boiled my battery....the EJ alt requires a signal from the EJ ECU to tell it how much to charge....if it doesn't get that signal it charges at 16.6V:eek:....and your battery boils its head off:mad:

 

i swapped the pully off the EJ alt onto the EA alt ( and had to shorten the spacer behind the pully to bring the engine and alternator pully into alignment)

 

i've been keeping an eye out for a nissan 90 or 100 amp alt but no luck yet

 

this is the kind of thing I was looking for, thanks

I too will keep my eye out for a nissan alternator.

 

thanks

Ben

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when i first swapped the EJ into my brumby i tried to use the EJ alternator.....it boiled my battery....the EJ alt requires a signal from the EJ ECU to tell it how much to charge....if it doesn't get that signal it charges at 16.6V:eek:....and your battery boils its head off:mad:

 

this is absolutely false. The alternator only needs a 12v reference signal to maintain proper voltage. On early legacies, it's tapped into the ignition coil power wire. has nothing to do with the ECU

 

you either had it wired wrong, or the regulator in your alternator had failed (happened in my dad's legacy...ruined a battery before we installed a volt gauge and realized what was happening).

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I had a alt from a SVX on my RX for about a month.

If you dont wire it right, you will fry fusible links.

I'm still having problems with mine after the swap, my black link dies after about 2mo (yes, its wired correctly).

I'm currently tossing around the idea of using the EJ breaker/relay box.

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It's not hard to wire in the EJ alternator to the L series wiring. This is how I did mine when I did the conversion, no ECU reference wire either:

 

ejtolalternatorwiringdi.jpg

 

This is for the series 1 and 2 alternators of the Gen 1 Liberty/Legacy.

 

Hope this helps.

 

Cheers

 

Bennie

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this is absolutely false. The alternator only needs a 12v reference signal to maintain proper voltage. On early legacies, it's tapped into the ignition coil power wire. has nothing to do with the ECU

 

thats what i was told prior to doing the swap....after boiling the battery i took the brumby into a very good local auto sparky...and he took one look at the alternator model and told me it wouldn't work without the an ECU to control it

 

so i had to put my old one back in with the new motor

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I looked at my 1992 FSM, and sure enough there is a wire coming from the ECU that ties into the alt circuit that is NOT there in the ea series cars. So there is SOMETHING else that helps with the charging circuit. I couldn't find much more info on this wire or what it does, but it does exist and it is not found in the ea wiring.

 

It's not hard to wire in the EJ alternator to the L series wiring. This is how I did mine when I did the conversion, no ECU reference wire either:

 

ejtolalternatorwiringdi.jpg

 

This is for the series 1 and 2 alternators of the Gen 1 Liberty/Legacy.

 

Hope this helps.

 

Cheers

 

Bennie

 

Since you came up with this el_freddo, why is it needed with the EJ stuff and not the EA? What wires do the letters correspond to?

 

I am interested in knowing why this is needed on the EJ stuff and not the EA stuff...

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I looked at my 1992 FSM, and sure enough there is a wire coming from the ECU that ties into the alt circuit that is NOT there in the ea series cars. So there is SOMETHING else that helps with the charging circuit. I couldn't find much more info on this wire or what it does, but it does exist and it is not found in the ea wiring.

 

It's not a signal coming from the ECU. It's just a 12 volt reference for the voltage regulator. It is tied into that circuit to insure that the voltages going into the ECU and ignition coil stay as close to 12v as possible.

 

 

Neither of the EJ swaps that I did myself had the alternator wiring tied into the engine/ECU wiring. One is close to 100k miles since the swap, the other over 30k.

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Since you came up with this el_freddo, why is it needed with the EJ stuff and not the EA? What wires do the letters correspond to?

 

When you look at the plugs on the EA alternator there are only two wires, the EJ alternator has three. Each letter corresponds to one of the wires as depicted on the plug sticker listing that each alternator has on them. It works a treat for me!

 

And as Numbchux has said, I too have not got a wire from the ECU to the alternator and have no issues running the EJ22 or the alternator.

 

Cheers

 

Bennie

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+1

All you need for an Ej alternator to work is a wire from acc on the ignition to the alternator. if you don't do this the alternator won't charge.

 

At first I just connected the wire directly to the battery. But when then engine is not running it will draw some current from the battery this way.

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sorry to revisit this.. again....

 

 

my EJ alternator only has 2 wires.

 

Milwaukee-20111021-00072.jpg

 

it seems the B/Y is the charge light, that would leave the other one to be the ign wire?

 

 

my 2 wires go into the stock ea connector. where does the other wire in the EA harness end up down the loom? at the ecu?

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Lots of contradicting info so far in here.

I see:

 

-some say it cooks the battery

-some say it works they have had it now for while no issue/

-some say it takes out fuseable links after a few months

-some people say the EA has 2 wires, and the ej has 3 wires, but look at the evidence above in the square with 2.

-etc.

etc

 

 

 

Now, any internally regulated alternator, with a failed regulator, will cook a battery, and maybe we are seeing some of that, it is a common fail.

 

Now, maybe we are seeing some that just have not run with it long enough to even know if they are cooking the battery. I can see that too.

 

what I don't like, is how much differing outcomes people have. And i do want to know the right answer, which so far cannot be gotten with the info here.

 

Plus there are 90-94 EJ round connector alts, and then the newer square plugs to throw into the mix as well.

 

Someone clear up what is being discussed.

 

 

brent

Edited by bheinen74

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The large white wire in the EA harness plug just ends up crimped back to the main alternator output wire.... usually back about 24" or more inside the harness. The white/red is the charge indicator/field flash wire.

 

GD

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i hear ya dude.

 

my main question is regarding bennie's diagram of the EJ and EA wiring. with the EJ having 3 wires in the connector. since mines got 2 (from 2000 Outback) im a bit confused.

 

the meter on the dash is near the top of 12v when driving, but when i turn on the acc is sitting slightly below 12v and drops down to like 8 or 9v when turning the starter initially.

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Do you have it wired as Bennie suggests?

 

 

regardin my alternator situation. it seems as my dash gauge reads lower than it should. my voltmeter on the battery shows 12v but its readin lower on the gauge, also when i hit my starter, the gauge drops almost down to 9v but the meter doesnt drop that much at all. i DO think i just need a new battery in general though. the water levels looked kinda low in it. maybe i can fill it up a little.

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I need help Im boilin my battery , how should it be wired? I have a EA82 spfi DL with a EJ engine so a round plug its a 90 help please

 

If you are boiling your battery, then you don't have the sensing wire hooked up most likely. The alt doesn't know when the battery is charged, so it just keeps on charging. Make sure you have it wired up like el_freddo's diagram…

 

As for the plugs, cut and splice to make it work...

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Ok, so what everyone needs to do is remove their alternator and have a look a the diagram in the sticker under it.

 

This sticker will give you a set of codes for each wire, a code that will line up with the below diagram in some way or another - I'm not 100% for the 2 wire alternator, the ignition wire might be built into the internals of the alternator.

 

Once you've checked out both stickers between the EA and EJ alternator and compared it to this diagram you should be able to work out what you're going to do to wire in the EJ alternator to the EA harness.

 

For an example, and while this is usually the method of sorting out an issue (sorry xbeerd) with a photo, in this case you simply cannot state that your alternator has two wires or three, the alternator's wiring diagram is what is key to this issue.

 

my EJ alternator only has 2 wires.

 

Milwaukee-20111021-00072.jpg

 

If your alternator has lost it's sticker, which can happen, you need to find someone with the same alternator or a wiring diagram for that model of alternator to work it out. If the letters don't line up, as in there are different letters used then they will have to be found out before you can match it up with the diagram below. I would like to note again that the below diagram isn't the answer to all alternator wiring conversions, it is for the Gen1 and I believe Gen2 alternators...

 

It's not hard to wire in the EJ alternator to the L series wiring. This is how I did mine when I did the conversion, no ECU reference wire either:

 

ejtolalternatorwiringdi.jpg

 

This is for the series 1 and 2 alternators of the Gen 1 Liberty/Legacy.

 

Now it did take me some time to get my head around it - it's the same as doing the wiring for your first EJ conversion, those who have done one or more will still remember their now naive questions asked before getting into the thick of it.

 

I hope this helps out, it all comes down to the wiring/plug diagrams!

 

Cheers

 

Bennie

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I rewired my alt now its charging a steeedy 14.5 Volt is that goood or whats the correct chage voltage rate?

 

Should be between 14.4v and 14.5v. So you are good to go!

 

Just make sure you keep an eye on it to make sure its not boiling over!

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