1 wire alternator wiring...

[mikracer]

I recently purchased a 58 Apache fleetside and I was going through some of the wiring under the dash to clean up the prior owners "work". It was down right scary, so I started cleaning up more and more until I got to the 1 wire alternator.

I traced the wire into the cab and up behind the dash. From there, it was hard to follow, but I eventually found that it led straight to the ammeter gauge. The other side of the gauge led to the +12 side of the starter. So the battery is being charged after being run through the ammeter gauge. Just wondering if this is the proper way to run the wiring.

[Speedbumpauto]

It's proper if you want to hang on to that ammeter. Should use a min 10 ga. wire. Many switch to a volt meter because of that wiring situation.

[Coupeguy2001]

I would split the load between the ammeter and just a regular 10 gage wire to the starter solenoid.
Usually those one wire alternators are 100 amps, and the ammeter is a 40 amp meter.
If you split up the load, so only half goes through the ammeter, it will indicate charge and discharge, won't be accurate, but wont burn up either.
Usually, the only time the amps should be really high is after a start, but if you add air conditioning, that is 45 amps.
You won't have it very long until the whole thing burns up.
brake lights, 3 amps
headlights and tail lights, 8 amps
cooling fan, 15 amps, approximately
heater motor, 4 amps
ignition, 4 amps
radio with a 100 watt amp, 25 amps
battery charge, 40 amps, dropping to about 3 amps
air conditioning, 45 amps
electric wipers, 7 amps
So you see, you want to be prepared for hot day, cold day, cold day and rain, etc. you get the drift.

[mikracer]

Thanks for the info guys.

Coupeguy... how do I split the load between the ammeter and 10 gauge wire to the starter solenoid? I think the safe route would be to just run the wire straight to the starter solenoid, but I like having all the gauges work on my gauge cluster.

[Coupeguy2001]

you need two wires on the battery lead on the alternator, one goes to the ammeter, one goes to the starter battery lead.
Say you have the ignition on, alternator charging, and lights on.
if you draw 7 amps for the headlights, 5 amps for charging, and 4 amps for the ignition, that's 16 amps.
Part of the load (battery charging) will bypass the ammeter, but the items taken from the ammeter to register a load will register as a negative load.
your charging amps will bypass the ammeter, and go directly to the battery.
This annoyed me for a couple hours, till I reversed the leads on the ammeter.
What this now shows is the amount of draw the load is making on the alternator, except for the battery.
What I did to get a representation of battery state of charge was to install a voltmeter that looks like the water, oil, amps triple gauges that the auto parts sells, and (not recommending this, but how I did it) I used a chassis punch, and punched out my cigarette lighter hole to two inches and put the voltmeter there.
Look at the pic and the gauge says batt chg

If you notice, all newer cars have volt meters instead of ammeters. They don't care how many amps the alternator puts out since the alternator is a constant potential charging system. (that means that the voltage regulator is set up to seek a voltage).
That voltage in turn puts a voltage signal in a different place in the voltage regulator, and tells it what the battery is doing volts wise.
the higher the volts, the lower the charging amps.
The load, (say 25 amps) tends to drag down the battery. when the voltage goes down, the voltage regulator biases the output transistor to strengthen the field coil voltage in the alternator, and it raises the volts in the battery/electrical system to keep the volts at 14 on the battery lead coming out of the alternator.
If the load is constant, the bias voltage is steady.
Say you have the turn signal flasher on, the bias voltage is jumping up and down to keep the battery at 14.
So based on today's engineers, the alternator is working if you have the same voltage day in and day out.

So the battery in my truck runs at 14 volts (on the gauge) from the voltage regulator in the alternator, and the ammeter registers the load on the truck wiring in amps as a positive. with the flasher going, the ammeter moves up and down as well as the voltmeter.
That's how I did it.

[mikracer]

Thanks for the explanation. I did buy a 3 gauge pod from summit and its waiting to be installed. Its either going in the glove box or under the dash, just not sure yet. I'll follow your instructions and wire a second charge wire straight to the battery/starter and swap the leads on the ammeter.

[tmoble]

What coupeguy said. Plan is to transfer heavy loads either charge or discharge off the amp gauge. It was meant to work with a 12V generator that would having a really good day to produce 20 amps. It didn't really need to do any more than that because the only time there were heavy charge loads were if somebody left the lights on and killed the battery, jumped it off and disconnected the jumpers. Still not a good plan, alternators really don't like this either.