[FC] One Wire Alternators

[Chris & Bill Strickland]

> > And wouldn't the whole "one wire" thing be incorrect if I have to
> > hook up other wires to make it operate correctly?
>
>
>  You're correct there - I'm not sure why they're called one wire. You
>  really need to hook up three wires.


Because (here is where I don't say, "people are stupid") it is NOT a 
one-wire alt if it has three terminals, B+, R, F, and ground.

One Wire alternators have a special self-energizing regulator, the 'one 
wire regulator', that takes the place of the ignition connection and 
leaves no place to hook up the idiot light.  One Wire units are truly a 
one wire hook up to the battery, period, if you bolt the alternator to a 
grounded engine.  They have no other place to make a permanent 
electrical connection.  They are not a two or three wire unit as is 
appropriate for running the Fan/Alt (belt) light on a Corvair, and it is 
a mistake (we all make them) to call them something they are not.  They 
also work best on vehicles that are not parked for extended periods of 
time.  More at http://www.alternatorparts.com/FAQ.htm#one%20wire

It is easy to convert a "one wire" to a "three wire" -- just replace the 
internals  with the appropriate parts. Should someone want to, 
instructions for going the other way, One-Wiring Your Own Delcotron 
10-Si Alternator, can be found at 
http://www.classictruckshop.com/one_wire_page2.php

Now, that said, the unit under discussion, putting out 18 volts with a 
single wire connected, is probably defective and needs to be or replaced 
or repaired.

The only advantage a one wire alternator has is reduced wiring and 
clutter in the engine compartment, so to that end, it would seem silly 
to add a relay to the system, at least to me.

Perhaps a primer on "Wiring the Si series alternator"  would be helpful 
-- http://www.alternatorparts.com/FAQ.htm#how%20to%20wire

On a Corvair, connecting the key switched Fan warning light to the the 
#1 terminal on a two or  three terminal internally regulated Si 
alternator, along with hooking up the battery wire and having a good 
bulb, will give you a working alternator with a minimum of wiring.  If 
you have a good regulator, a connection to the #2 terminal is not 
required -- it can be "jumpered" to the B+ terminal if you feel a need 
to hook up another wire, but it should not be necessary.

Bill Strickland