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RenaissanceMan

Does anyone know about the alternator swap?

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So I dont know if other people out there have problems with the older mechanical regulators failing on you, but did anyone already know how easy it is to change over to the newer ea81 and ea82 internally regulated 60-65 amp alternators? heres the simple writeup on it. I dont think this will work on anything 75 or older because they might have had a different connector that I havent looked at.

 

1.Disconnect the Battery

2.Remove your ea71 external regulator alternater.

3.The bracket that holds the adjusting side of the alternator needs to be removed, and like.. hit it with a BFH while in a vice or something. Just a minor adjustment needs to be made.(the internal regulator alternators are about an 1/8th inch wider than the older ones)

4. Put the bracket back on the motor, bolt on the new alternator, and hook up the wires, yes they just plug right in. If yours has a wire for the ground on the alternator, you can change that connector over to an eyelet or something and bolt it on, but its not necessary if your engine is grounded like it should be. (the adjustment will be on the outer reach because of the belt size, if you want to get a 1/2 inch shorter belt you probably can, but didnt have a need to.)

5. Take off the external regulator on the passenger side, clip off the connector and throw that junk in the garbage, but keep the connector with signifigant pigtails. If your regulator had a noise suppression capacitor bolted to it, just bolt that back on the fender.

6. Take your ex regulator connector in hand, and all you have to do is make 3 connections, just 3.

Take the blue wire and connect it to the black with white stripe wire.

(crimp, solder, wire nut, masking tape, w/e)

Take the white wire and connect it to the yellow wire. (if your yellow wire

has a fuse on it, take that off, you dont need it)

Take the white with red stripe wire and connect it to the white with black

stripe wire.

7. Insulate your connections with some shrink tube or electrical tape and plug the connector back into its other end on the harness. If your harness also had a separate black wire going to the regulator, you can ground that to the chassis as well, thats simply the same wire you saw on the other end grounding your alternator.

8. Plug your battery back in, and thats it. Your set. The fuel pump turns on with the ignition, and the light goes out after the engine is running for a couple seconds.

 

 

In only 8 steps you too can have a Gen1 vehicle with a 65 amp alternator for your bumpin stereo right?

 

 

-Mike

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Oh thank you!! I didn't know what to do cause I just threw the EA81 alternator into my brat and IEEE! I didn't know you had to change the wiring too. thanks a bunch - this is gonna help a lot!

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Hey did you you have any problems with your idle after the swap?

 

After I did the swap, my idle varies considerably. Whe I start it up I idle at 800-900 rpms, but when I turn on the accessories, It goes down to about 500-600 rpms. If I drive for a while with no accessories on the idle goes to about 1100-1200 rpms, but when I throw on the accessories it goes down a few hundred rpms. Also, if I've driven for awhile and then idle for awhile, the rpms go from 1100 to 900 really slowly.

 

Any ideas? could I have connected the wrong wires? Did this happen to anyone else? I tested the alternator and it was fine.

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It kinda sounds like its doing what its supposed to be doing. The low Idle when you first start up is the choke idle up not being adjusted properly or something. But when you let it sit after driving it it goes from 1100 to 900 slowly, thats what its supposed to be doing. On the carburetor there is a "dashpot" that, after accelerating, holds the idle high for a couple seconds before letting it drop down to set idle. This prevents excessive emissions. Was your brat not doing this before?

 

-Mike

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It kinda sounds like its doing what its supposed to be doing. The low Idle when you first start up is the choke idle up not being adjusted properly or something. But when you let it sit after driving it it goes from 1100 to 900 slowly, thats what its supposed to be doing. On the carburetor there is a "dashpot" that, after accelerating, holds the idle high for a couple seconds before letting it drop down to set idle. This prevents excessive emissions. Was your brat not doing this before?

 

-Mike

I'll put in my 2 cents, since I helped test the alternator on this brat. That should be "goes from 1100 to 900 s-l-o-o-o-o-o-o-o-o-o-o-o-o-o-o- " ...well, you get the idea. In fact, I don't think I ever heard it drop. Longer than just the lag to control emissions.

 

That said, I gotta add that it didn't seem at all alarming to me.

 

btw, electrically it was doing the right things. At idle, it was making about 2-3 amps at about 14.7 volts; turned on the accessories and the idle dropped down a good bit, but made about 25 amps at about 13.5 volts. No clue what those alternators should do, but when we asked for power, it stepped up, so I figure it works.

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Will a alternator from a EA-82 engine work for this swap Mike? If not I guess I will have to hunt down the correct alternator before I finally give this one a shot. You should post pictures of this proceedure too.

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any internally regulated alternator will work... hell if you want to throw a delco alternator on there all you would need to do is buy the connector at the auto parts store and put on one of those alternators instead... truth laid out simple... all internally regulated alternators are almost identical, you just gotta know which pins to use and where they go.

 

-Mike.. (I might be able to get a picture in a couple days.. things are going kinda busy right now cause later this week I drive out to a "Fly in" as the Rotordyne subaru engine representative.)

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while you're at it, put on the xt6 alt instead

I used a washer as a shim, added a case ground, and ran a alternator output wire from a vw, 8ga iirc, and another alternator output wire, and used a side post battery plug as an insulating adapter, works great

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It seems like everyone can use this forum search function but me... I have never been able to find anything useful using the search.

 

Anyway, yeah it eliminates the function that keeps the fuel pump from running without the charging system functioning.

 

This has its ups and downs. My thoughts were, with the points ignition you dont want to be leaving your ignition on anyway. Also all my gen1 carburetors leak the fuel out of the float bowl, so using the normal safety system it would take for ever to get it to start because I would have to crank it long enough for the fuel to make it back up to the carb.

 

I guess the down is that if you got into a fender bender in a bad situation it would keep pumping fuel, and if you werent concious to turn off the ignition then you could be in for a world of hurt.

 

hmm..

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I'm trying this swap on my ea71. i took off the external regulator but i have 2 black with white stripe wires. one is clearly a white stripe, the other is a slightly greenish white stripe. which one do i connect to the blue wire, and which one should get grounded. in addition there is a separate black wire comming off of the regulator with a female end on it that is not connected to anything. if you look at the wire pattern on the back of the circular connector (clockwise) it goes blue, black/white stripe, yellow, white/black stripe, white/red stripe, white, and in the center is the black with the slightly greenish wire. the solid black wire commonig off of the old regulator with the female end is not part of the circular connector, but it comes out of the same cluster of wires on the side of the regulator. I wish i had a digital camera to post a picture. any links to wiring diagrams, or help?

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I'm bumping this to see if I can figure this out for my car right now.

 

Here is my wiring:

 

whattowire.jpg

 

I need to figure out what to splice and where...

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