My '67 Fury has stopped charging for some reason. Last year I converted it to a solid state voltage regulator and the altenator with the two field terminals. It has been very well until now. The battery is a little over a year old. I had to use a booster pack to start and when running at a fast idle, the amp gauge shows only a slight charge. At the battery terminals I get 12.5 volts at fast idle. The headlights are also dim. Any ideas on how to locate the source of the problem will be greatly appreciated. Thanks.
John

first you may want to jumper the amp gauge and test for voltage at the battery with jumper on and off. could be the bulk head connector too??

Quote:

---

At the battery terminals I get 12.5 volts at fast idle.

---

That's to low, you should see 13.5 to around 14.5 volts. Check your ground on the voltage regulator and check for loose connections on the alternator and regulator. The screws that hold the regulator to the fire wall usually are the ground for the regulator, so check for problems in that area.

There are a lot of places it could go bad.

12.5 is not really charging. Should be around 12.8 or higher to even remotly be considered charging.

At rest with nothing drawing a good battery should put out around 12.7.

Put a 12 gauge wire from the back of the big bolt on the alt directly to the battery and see if you start charging. This will show your components are good. If not then you have some replacing of parts to do.

If it does charge, then you have to trouble shoot your wiring.

First measure your battery voltage.
Then with the key in run, measure the voltage at the VR and the back of the Alt.

Start the car, measure the battery voltage.
If everything works, then your bulkhead is getting voltage into the car, but the question is is it coming out.

Next you have two big lines coming out of your bulkhead connector. check for voltage going in and out. If it isn't making it out, it is either your amp meter, or the bulkhead connector.

Andrew left a few things out.

First thing I'd do is see if the path from the alternator/ wiring/ bulkhead/ ammeter/ battery is good. So as andrew said

WITH engine simulating "low cruise" jumper from the big alternator stud (output) directly to the battery, see if the voltage goes up. Double check by checking the voltage at the battery, and at the stud. They should be close, within 1/2 volt or so

If this is good, see if the alternator will charge. Here's how these work:

Both the regulator ign terminal and ONE terminal of the alternator field "get" switched ign from the key. On a stocker this is the blue wire, so with the ign in run or the engine running, make sure the ign terminal of the regulator is getting battery voltage, and identify which field terminal is doing so--if it is. If so, hook that one up, and disconnect (normally green) wire from the opposite field.

Now with the engine running low-to med. cruise, GROUND the exposed terminal of the alternator field. This should give you battery (12V) from the blue--through the field--to ground. THIS SHOULD CAUSE the alternator to go to "full output" You should see a dramatic rise in voltage at the alternator output stud AND AGAIN this voltage should be close to the battery voltage, say, within 1/2 or as much as one volt difference FOR NOW

If you get this far, and it charges, it's starting to sound like the regulator.

If it does NOT, shut everything off, take your meter, and see if you have continuity through the two field terminals. You MAY just have stuck/ worn brushes, an easy fix. If you DO have continuity, and you did not get any output, verify that the field draws current by jumpering power to it--battery to one terminal, ground to the other. You should see a small spark. Double check, and if no output, you probably have diode/ stator troubles==new alternator

Remove the regulator, scrape the ground clean, hook it up and make sure the connections are tight and double check it. If you are sure it's grounded, if you are sure the (normally green) wire from the regulator to the one field terminal is "continuous" and if you are sure that you are getting "ign run" (battery) voltage to the other regulator terminal, it's time to try a new one.

Hey Guys,
Thanks to all for your detailed posts. I am going to get the car tommorrow (Tues). I will check it out then. Thanks again.
John