Voltage Regulator?

67Dart273 said
The battery voltage is not too bad. The alternator output is not too bad. There will ALWAYS be a voltage drop between alternator output and battery in these girls, unless you bypass the entire circuit with a large ga. wire direct from alternator to battery IE no 6 wire, etc

Here is the deal. There is typically voltage drop in the VR / ignition circuit which causes the battery to run high. There are two ways to check for this

1.....With engine warm, battery "normalized" and engine running on fast idle (to simulate low/ med cruise RPM and to insure that VR/ alternator are "up") Measure ignition voltage where it goes to ballast resistor. Measure from ballast IGN "run" terminal to VR ground. If this is in spec (see chart in service manual) 13.8--14.2 when warm, then VR is OK and any other voltage "at battery" means a harness voltage drop problem

2....Second way (how I do this) is turn key to "run" engine stopped. Measure between same point as above (ballast IGN RUN) and battery PLUS terminal. You are hoping for a very low reading. If your read more than a few tenths of a volt you need to get into "why." ----and fix it

Just one way is to use a relay triggered by the key, to power underhood loads

Let's say you measure .5V in test "2." This means that if the VR is actually charging at 14.2, and you have .5V reading with test "2" then that .5V will ADD to the 14.2, and the battery will run about 14.7V

This drop comes from the VR supply path which is ..........battery---------starter relay stud----------fuse link--------through the bulkhead on RED ammeter wire--------through ammeter-------out on BLACK ammeter wire----------to underdash welded splice-----------branch off to ignition switch connector---------through connector, switch, .........back out switch connector..........on "ignition run" (IGN1) .........back out through bulkhead connector.............to underhood ignition loads.

EACH OF THE POINTS above, between the dots is a point of bad connection and potential voltage drop. These drops ADD. IE if you have .2V drop through switch, and another .4V through bulkead connector RED terminal, and .1V through bulkhead terminal for the ignition "run" wire, these all add up in series

@67Dart273 I found your test criteria on another post and I was out checking!
With the key on I get 1.1V at the ign terminal on the regulator. Unplugged I get .5V on that wire.
I get .9V at the blue wire on the ballast, plugged in but not running. Unplugged I get .45V

Interestingly, I get 12.4V basically battery voltage at the ign terminal of the regulator with the wire disconnected, motor not running. Is this normal or is it shorted through?

The underdash wire from the ammeter has been replaced with 10ga and the splice resoldered and 10 ga run back out.
It was spliced with lampcord and wirenuts when I got the car, don't ask..... :eek:
The 2 heavy leads through the bulkhead connector were burned off, and the new wiring is run through a grommet in the firewall.
I have cleaned the remaining bulkhead connector leads.
This is a convertible that sat with a destroyed top, the floors have been replaced, and there is actually some small spots of surface rust above the inst panel under the curved part of the dash.
I'm thinking there is most likely some internal wire corrosion..... :(