Charge Wire Change Motorola Alternator

If I got your system right in my head, I know my head ant right, it is almost like my drag car. For a test pull the wire off the ALT output, tape it up good because it would be hot from the SOL side because that is where the batt hooks to right? Run a 10 ga. Wire from ALT output back to the batt and see what happens? Think that would be the same as the drag car and the power for the car gets picked up at the SOL where the batt + and other wires hook to. If works then fuse both ends of wire and run it thru car to look nice nice.

BTW what are you using to draw out the systems in this post? Something you can get cheap like standard MS Visio, not that it all that cheap. Would be nice to redo the print of the drag car wiring and update it as I added MSD setup. That and hard to read now as I did it in pencil & paper got oil on it, yep hard to read!

Dave ----

Still have low confidence in charging system operation.
Added (2) Grounds to pass side block to chassis.
1 braided at starter b-hsg bolt to strut rod brkt frame bolt.
1 batt cable type Alt Pivot Bolt to Idle Arm frame stud.

Could my Charging System and/or ALT Dash Light "problems"
be being caused by the (2) Ballast Resistors "bandaids",
needed in order to make the MSD Box work with
the stock Tach & Motorola Charging System,
attached to the coil end of the stock Coil "+" wire ?

The Stock Coil "+" wire is common with (1) side of the ALT Light circuit.

Note that the stock Coil "+" wire no longer goes to the Coil.
It is only used as a "signal" by the MSD Box.
Coil wires are now Orange and Black direct from the MSD Box.

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I run a Delco Distributor UniLite triggered MSD Box
an use the stock in-dash 1969 AMX Tachometer.

Had (2) issues when MSD box was 1st installed.
1. Engine run-on, keep running with key off.
2. Stock Tachometer not working.

Fix for both issues was found in the MSD Instructions
and each called for the use of a Ballast Resistor,
but not in the common way used to drop feed voltage.

1.) Engine Run-On Fix

Dual Ballast Resistor at Coil "+" end of STOCK Coil wire
both ballast in series and then attached to GROUND.

2.) Stock Tachometer Fix

Single Ballast Resistor ACROSS the MSD RED & WHITE pick-up wires.

This means at the coil end of the original Coil "+" wire
I have (2) connections to (2) different Ballast Resistors,

#1 to prevent engine run-on
(1) double resistor to ground

#2 to use stock tachometer
(1) single resistor across MSD Red & White
    (orig Coil "+" wire attaches to MSD Red)
    (stock current triggered tach)

For the MSD to work with the stock Tach
a 2nd single Ballast Resistor is needed
and one end of it also attaches to the Yellow Coil Wire.

Charging System component and connection checks are ok.
Charging System operation seems intermittent or unreliable.
Trying to find what in the system seems to be preventing
the charging system from increasing output with system load.
Wondering if these (2) non-stock Ballast Resistors
attached to the Yellow Coil Wire,
which is part of the Charging System ALT Light circuit,
may be casuing or part of the problem.

Half tempted to switch back to Points just as a Test
to see if there are any changes in the Charging System operation.

ALT Light "Problem"
I'm getting the "Rambler Glow" on the ALT Light
not visible durring the day, visible at night.

Voltage seems ok sometimes, no in-car gauge.
Voltage does seem to drop when at 2k idle
from what it reads at 700 idle, which is odd.

Voltage at battery drops with high beams and blower on.

Full Fielding showed like 18 volts at the battery.

Main "Problem"
It's like the system is not sensing any increased load
and compensating for it by increasing alternator output.

MSD
All it is with an MSD box is that
the stock coil wires attach to the MSD Box and
the MSD Box has it's own wires that attach to the Coil.
All the MSD does is take-over feeding the Coil.
The MSD has its own Orange & Black Coil wires.
Only these are attached to the coil, nothing else.
The MSD uses the stock Yellow Coil Wire as just a "signal".
The MSD can be triggered 2 ways, Magnetic Pick-up
or non-magnetic like Points, or UniLite, or XRi, etc.
If triggered non-magnetic a pair of wires from the MSD Box,
Red & White, are used to pick up the trigger signal.

To make a factory '69 AMX current riggered Tach work
with the MSD a Ballast Resistor must be wired in
across the Red & White MSD "signal" pick-up Wires.
The stock Yellow Coil / Tach Wire is attached as a "signal"
to the Red MSD wire instead of being attached to the Coil.
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On the Ignition Switch,
coming from the same post as the Pink Resistance wire,
is the Yellow wire that goes to the Voltage Regulator.

This Yellow wire has a "T" union marked "C" on the '69 TSM Schem.
At this "T" the other Yellow wire branch goes to the Fuse Box,
through a 4 Amp fuse, and exits as the Green wire that runs
from the Fuse Box to Instrument Panel, through the ALT Light,
then out of the Inst Pnl through an Orange w/tracer wire
that runs out to the Voltage Regulator.

The Dual Ballast Resisitor attaching the Yellow Coil wire to Ground,
which seems really odd to do but that's what was in the MSD docs,
does cure the engine run-on problem the MSD box first had.
It's just that the dual ballast resistor is not being used conventionaly,
it's not being used to drop coil feed voltage,
it being used to ground the yelow coil + wire
which somehow counteracts the "leakage" or "feedback" of
power through the ALT Light circuit on stock '69 AMC wiring
with a Motorola charging system when the ignition is turned off.

There was more than 0.9 Volt difference,
 1.23 to 1.38 volts diff

15.04 = Volts at Regulator ORANGE Wire at Idle
14.91 = Volts at Regulator ORANGE Wire at 2k

13.81 = Volts at Alternator Output at Idle
13.53 = Volts at Alternator Output at 2k