oletrucks
[Top] [All Lists]

[oletrucks] alternator wiring

To: Old Trucks List <oletrucks@autox.team.net>
Subject: [oletrucks] alternator wiring
From: J Forbes <jforbes2@mindspring.com>
Date: Thu, 12 Jun 2003 11:11:03 -0700
> Date: Wed, 11 Jun 2003 18:38:19 -0400
> From: "Tom C." <c_tom@bellsouth.net>
> Subject: [oletrucks] el camino alternator wiring...off subject??
> 
> I hope this isn't off subject, but if anyone knows how to wire this i know
> some guys on the list do. If it is to far off subject please accept my
> applogies, and anyone would like to answer please ping me off list....thanks
> I have access to a 1984 305 Chevy motor. It runs good and is in an El
> Camino, which i think is the same as a Chevelle. It runs great, but some
> alterantor wiring may be wrong.
> I hope this don;t confuse anyone....

I have the same alternator on both of my oletrucks, so it's on topic 
(just pretend you've already installed the engine in an oletruck)

> On the back of the alternator there is a clip with two wires and another
> slightly larger wire that is by itself on a post.. The wire that is by
> itself goes from the alterator to the pos side of the batt.
> The little connector on the alternator, has two wires coming from it. One of
> the wires looks like it goes to the Amp gauge and the other wire loops over
> to the other wire on the alternator post, which don't seem right.
> Problem is the wire coming from the + side going through the connector which
> in turns goes to the alternator gets very hot, almost to the point of
> melting. The amp gauge also drops to about 10 or less amps when the lights
> are on.
> 
> With all that being said, does anyone know the correct way this alternator
> is suppose to be wired??

When you say "amp gage", I'm not sure exactly what you mean.  GM quit 
using ammeters a long time ago, so you might be talking about the 
voltmeter in the 84 El Camino.  If so, then it sounds like it's not 
charging properly, if the battery voltage is about 10 volts with the 
lights on.

Just a quick electrical refresher:  Amps are how we measure current, 
which is how much electricity is flowing through the circuit.  Voltage 
is how "stong" the electricity is, and in most automotive circuits it is 
usually about 12 to 14 volts. So, and ammeter will show you how much 
current is flowing into or out of the battery (for example).  A volt 
meter will tell you how much voltage is available to do work.

On the 10-SI alternator, which was used on GMs from 1973 till sometime 
in the late 1980s, there is a two wire plug in connector, and one screw 
terimnal.  The screw terminal connects to the battery, this is the 
alternator output connection.

One of the two wires on the connector is a voltage reference (the 
alternator is marked "2" and "F" at this connection), so the internal 
voltage regulator will know whether to charge or not.  This red wire 
connects to the battery also, and it can be connected to the screw 
terminal for convenience (this is how my trucks are wired).

The other wire on the connector ("1" and "R" marking) is either brown or 
white, and energizes the regulator.  This wire connects to the ignition 
circuit (energized only when the ignition key is "on) through a 
resistor, or a resistor wire, and/or the "ALT" idiot light.  It should 
NOT be connected to an ammeter!

If the wiring is ok, it is possible that the alternator is bad.

If this doesn't get you straightened out, keep asking questions...
-- 
Jim

Visit the Selectric Typewriter Museum!
http://www.mindspring.com/~jforbes2

59s in AZ
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959

<Prev in Thread] Current Thread [Next in Thread>