Alternator Charging

[nivvy]

Its not charging at 13 volts.. its charging but at 12    

[MEK-Dangerfield]

I'm guessing it isn't charging and you are just reading what is left in the battery.   

If not a bad alternator, then voltage regulator. The regulators are cheap to buy.

I'm guessing you are looking at an aftermarket voltage gauge while the car is running. If so, I don't like this. 


  mike

[nivvy]

I'm guessing it isn't charging and you are just reading what is left in the battery.   

If not a bad alternator, then voltage regulator. The regulators are cheap to buy.

I'm guessing you are looking at an aftermarket voltage gauge while the car is running. If so, I don't like this. 


  mike

both are new... but i had he alternator replaced as the last one wnet bad.... not an electrical expert but what is the best way to tell???

[Changin Gears]

The simplest, quickest way to tell if you are charging is to touch the center of the back of the alternator with a screwdriver or something steel.  When the engine is running the alternator become magnatized and will pull the screwdriver in.  Not running their might still be a little pull.  What is good about this test is you can do it on the side ofthe road or anywhere.

[Bullitt-]

Simple thing, that having your motor apart you may have overlooked, is the motor to body ground strap that goes from the right side valve cover to the firewall.

Have you bypassed your ammeter yet?...might be a good time to do this.
http://www.madelectrical.com/electricaltech/amp-gauges.shtml

[nivvy]

this i my 3rd walmart battery the other 2 went bad an im thinking this one is also... if the battery is no good again will it not show charging on the volt meter???

[hooD]

Simple thing, that having your motor apart you may have overlooked, is the motor to body ground strap that goes from the right side valve cover to the firewall.

Have you bypassed your ammeter yet?...might be a good time to do this.
http://www.madelectrical.com/electricaltech/amp-gauges.shtml

Thanks for the link....I'm going to study it and decide if thats what I want to do on my Cuda. 

[hooD]

this i my 3rd walmart battery the other 2 went bad an im thinking this one is also... if the battery is no good again will it not show charging on the volt meter???

Have you tried putting your battery on a battery charger? 

What happens when you do?  Does it take a charge and then "zero" down to normal?

If your battery charger is throwing a charge into the battery and the battery is holding it, then I would think that your alternator is bad.