Re: alternator wiring problem/ Please help!!!
"BAT terminal to constant hot side of starter solonoid.
#1 terminal to the neg. side of a switched indicator lamp.
#2 terminal to constant 12 volt (on the battery) for sense."
OK so far...
#2, should be the larger of the two wires, and can attach to constant or switched sources...
NO MENTION OF DEDICATED GROUND FROM ALTERNATOR TO BATTERY...
No mention of a fusible link inline at the starter solenoid either...
"I should also state that I have a Sunpro amp meter in line on the charge line, to the solonoid."
Now here is a problem...
There is a reason not much comes with an 'Amp Meter' anymore.
Unless you have a 'Shunt' type Ammeter, this may be your problem. The 'Amp Meter' can't handle charging systems over about 35 or 45 amps, and most of us have larger alternators (and loads) than that.
If you have a 'Shunt' type ammeter, the shunt can be causing problems.
Both the amp meter and the shunt can have grounding out issues, and if either one goes (depending on system) it will look all for the world like a bad alternator.
That's why most of us use volt gauges instead of trying to use amp meters.
"When I hook the wires up like this, the indicator lamp is on, and the alternator does not charge. The battery just runs down."
What kind of 'Light' do you have in your system?
Most light sockets ground through their housings, and if this is the case, it's the light socket doing bad things to your system.
See, the #1 wire is the excite wire, and it supplies current to the voltage regulator to get things started.
When the alternator is not generating (as in stopped) this terminal is a GROUND, and your light is 'ON',
When the alternator starts to produce, that terminal becomes 12 volts POSITIVE!
This means if you have a bulb socket that grounds through the housing, you are grounding out the regulator!
What was a ground, keeping the light on, is now positive and the light goes out, but you can't let that circuit go to ground at the light or the regulator can't work.
Look for a socket that has two wires and a plastic housing or insulated housing.
The socket you use must have a CONTROLLED GROUND, and that ground must be attached to the #1 terminal.
You can also try installing a diode at the #1 terminal, with the stripe facing the alternator.
"In my experimenting, I have found that if I hook up the #1 terminal to constant 12 volts, switched or not, the alternator charges at a rate of about 30 amps, according to the meter, and the jeep maintains 14 volts at idle."
This would reinforce what I'm thinking about the bulb socket.
With 12 volts straight to the #1 terminal and no resistor you are going to get continuous 'Full Field' effect from the alternator, and it's going to overcharge the battery.
"This seems correct but why does it work, if the wires are hooked up wrong? Also, when hooked up this way, the BAT terminal gets very hot. Is this tricking a faulty alternator into working? Or is the battery just really dead and this terminal would only be hot until it is recharged?"
You are pretty sharp, done your homework...
You ARE tricking the alternator into producing at the limits of it's ability.
Battery terminal will get very warm (not hot) unless you are over charging it, throwing AC current at it (if the diodes in the alternator are bad), or the connection is faulty (not tight, crud covered, corrosion in terminal or on batt post) or the battery is shot...
"According to the amp meter instructions, the meter should only really read less than five amps at idle."
Five amps is normally about the 'Running Drain' of the average vehicle, with all accessories off.
I'm still leery of Amp Gauges. Like I said, the entire current from the alternator runs through there, and if something goes wrong with the amp gauge, it's going to look a whole lot like a bad alternator.
Here are the recommendations,
1. Take your alternator to the local auto parts store and have it tested. (free)
2. Charge the battery with a battery charger before trying to diagnose the vehicle. (free)
3. Run an 8 or 10 gauge ground wire from the back of the alternator to the negative terminal of the battery. At least as big a wire as you used for the 'Battery Charge' wire. (appx. $2)
4. Install a 12 gauge fusible link in the master charge wire at the starter solenoid. (appx. $3)
5. Take your light socket out of it's mounts (so it can't reach a ground) and see if the problem corrects it's self. If so, you need a controlled ground light socket.(between $3-$10)
Time to test the system...
6. Install Radio Shack p/n 276-1144 diode with the stripe facing the alternator.(appx.$2)
(there will be a stripe on one end of the diode)
This is a safety feature that keeps your charging system from going to hell if the light wiring gets grounded out again.