1 wire alternators

[karolko]

I am loking to find a new replacement to my old and tired alternator. i have read from and old post that most late 80's cadillacs and 86-88 fwd buick and olds cars had alternators that would work just fine.

two questions that i would like clarified, first, our TR have only one wire going into the alternator plug, but from my memory, all the other alternators i have seen in the junkyard have 2-3 wires coming out of the plug? Are they still interchangable while using my 1 wire plug? or do i need to make wiring modifications?

Second, WTF is re-clocking??? I know stupid question.


Thanks alot boys,

Adrian

 

[ijames]

No help on the wire question but clocking refers to the relative orientation of the connectors on the back cover of the alternator and the mounting ears attached to the front cover. To reclock, you take out the four bolts holding the covers together, hold the back cover, and spin the front cover. Just don't pull the covers apart too far or the brushes pop out of place and you have to take it all the way apart, reseat them, hold them with pins through the holes in the back cover, reassemble, and pull out the pins. Many cars used the same alternator, just clocked differently to line up with all the possible wiring harness and mounting bracket choices on different engines. Rather than stock two or three different parts, the aftermarket just supplies one part number and you reclock it as needed before installation.

 

[karolko]

ijames, that is a perfect explanation of how to re-clock. Now that this has been figured out, all i need to know is the 1-wire gig.


Thanks alot,

 

[BiGBoY]

Yeah a lot of GM Cars use one wire alternators. All GMs I had in my life so... Cavalier, Firenza, Sunbird, '80 350 LeSabre, '89 307 Caddy, '82 Park Avenue and of course my 78 Century with a stock 63 amps unit...

A One wire alternator simply means that it only requires one hot wire from the alternator to a postive battery connection. It can be also refered as Output Wire (a car can be connected to the positive side of the battery or to the positive side of the starter solenoid)...and thats surely your case.
Yeah you have a multiple connections to your alternator, but not all intended to charge your battery.

-One wire (hot wire) that supplies current for the battery
the others are:
-one for ignition input that turns on the alternator/regulator assembly
-one used by the regulator to monitor charging voltage at the battery
-one wire the regulator uses to ground the charge warning lamp

Hope it helps !

 

[karolko]

Hmmm this is all interesting, I understand that the one large red wire that jsut goes onto the battery terminal for charging and all, but all the other wires on the plug, is what had me confused, but what you are saying is that even if these other junkyard alternators have more that one wire coming out of the plug, that it is still compatible? By the sounds of it, the other wires are only for a voltage indicator light, is that correct?

Slowly i am getting to my answer.

 

[Race Lutz]

ijames, that is a perfect explanation of how to re-clock. Now that this has been figured out, all i need to know is the 1-wire gig.


Thanks alot,

I was thinking the same thing. Good job ijames!!!

 

[BiGBoY]

the easiest way to find an alternator that fits your need is to look carefully to your alternator.
As my Buick is garaged away from me for winter I can't show you mine sorry

So with your alternator in hands looks where the hot wire is. And see where the other connection is (the multiple connection)and the way its made. Find one with the sames connections, keep it simple.
In Looking for the same kind of alternator, G-body car is a good place to look at. But there are a lot of GM with the same alternator connection like cars of the same years of your car. (for example I could have change my alternator for a 80 Trans Am 301, same same same thing for my buick)
Olds car had 63 amps units, newer had something like 92, and last GN over 100 amps I don't remember.
If you choose to go with a brand new one take a look at this web site, especially to the 105 special alternator, 105 total amps, and 42 amps at idle
Performance Distributors - High Performance and Racing Ignition Systems

 

[turbofish38]

The most plentiful direct swap plug and play alternators out there are the 120A units used in the 86-93 Cadillacs with the 4100/4500/4900 V-8. All you need to do is swap the pully.And fan if you like the stock look. Probably the second most common alternator are the 140A jobs used on the 94-96 LT1 B-Body(ImpalaSS,Caprice,Roadmaster). No need to swap the pully on that one. Don't pay any attention to the position of the wires on the plug.

 

[karolko]

turbofish, thanks for the help,

while we are on the subject, i with my car, i have no stereo, only power windows, ecu, headlights and most importantly the coil pack,

in my particular case, would there be any reason why i should be running the highest amperage alternator possible???


Thanks alot boys,

Adrian

 

[turbo96max]

alternator

great thread. i thought gns brought 120 amps alternators already? either way the 95 b body will work plug and play?????

 

[turbo39151]

the 140 amp unit off the 95-96 Impala is a direct plug and play. I bought mine brand new so I would have a lifetime warranty from Napa. I also upgraded the positive and negative ground wires from the wimpy stock stuff to 2 gauge and 4 gauge wires. No issues- ever!

 

[Red Regal T]

the caddy alternators are supposed to be 120 amp. The pulley is wrong and it's a pain to get off. Most times, you have to go to an alternator shop to get them to remove it. Besides those chevy alternators, which are used on many GM front drive models and vans, mentioned (I use one on my GN) many times you can get a 120 amp off Buick front drives. They have the correct pulley so you don't have to bother with it. As far as this one wire question, you simply insert your plug into the "new" alternator. The proper pin in the alternator will feed the juice to the plug.

 

[turbofish38]

The easiest way to remove the pulley is to use an 1/2 drive air impact. Just grip the pulley and pull the trigger. Off in less than a second. As far as the 120A Buick unit just look for the 120A stamped onto the mounting ear. They aren't as common as the 108A unit. As far as finding the correct pulley if you look along the lip of the pulley you should see 3 digits stamped there. Those are the last 3 digits of the part number. Just match up the numbers. BTW the 108A and 120A use the same pulley.:smile:

 

[Red Regal T]

The easiest way to remove the pulley is to use an 1/2 drive air impact. Just grip the pulley and pull the trigger. Off in less than a second. As far as the 120A Buick unit just look for the 120A stamped onto the mounting ear. They aren't as common as the 108A unit. As far as finding the correct pulley if you look along the lip of the pulley you should see 3 digits stamped there. Those are the last 3 digits of the part number. Just match up the numbers. BTW the 108A and 120A use the same pulley.:smile:

Not true with the Cadillac pulley. You need a special tool alternator shops have. They are not held on with the nut. Removing the nut has zero effect. They have a wedge retainer holding the pulley on.

 

[turbofish38]

No special tools other than an impact gun and socket....and of course air. I'm sure Bweavy can vouch for me as I just did one in the shop an hour ago. Slicker than snot I tell you. When I get the time I'd like to do an alternator restoration thread in the How To forum showing how to do it.

 

[Bweavy]

No special tools other than an impact gun and socket....and of course air. I'm sure Bweavy can vouch for me as I just did one in the shop an hour ago. Slicker than snot I tell you. When I get the time I'd like to do an alternator restoration thread in the How To forum showing how to do it.

No Joh I did hear him in the back playing with an impact. I was wondering what you were doing back there. I offered him a 140 or a 200 amp alt new but he said no because the case wouldn't be date coded.
We went diving Saturday & he lucked out & found it mostly pulled ready to go.

 

[Red Regal T]

No special tools other than an impact gun and socket....and of course air. I'm sure Bweavy can vouch for me as I just did one in the shop an hour ago. Slicker than snot I tell you. When I get the time I'd like to do an alternator restoration thread in the How To forum showing how to do it.

You seem pretty sure. Well, you are incorrect. Just to be clear, I'm talking the alternators taken from Cadillacs, Sedans, Eldos, and Sevilles. They have a totally different pulley fastening system and again, a special tool is required to remove the pulley.

 

[Red Regal T]

No Joh I did hear him in the back playing with an impact. I was wondering what you were doing back there. I offered him a 140 or a 200 amp alt new but he said no because the case wouldn't be date coded.
We went diving Saturday & he lucked out & found it mostly pulled ready to go.

The question is, what was he doing with the impact? I know he wasn't removing any pulleys from Cadillac alternators with it. :biggrin: