About a month ago my battery started discharging. I had the battery checked and it was okay, replaced the alternator (with Auto Zone's lifetime warrantied one) and it started and ran ok, still showed low charge on the gauge. I had to use my jumper box to start it once, then it worked for awhile (still not charging much) but quit again a couple of days ago, so I bought a new battery last night (Auto Zone's mid range) and put it in today. Started into town with it and it showed to be discharging slightly again, so I came back home. Have driven it a couple of miles twice this afternoon, still runs just barely in the normal zone.

Is the alternator bad, or could it be something else, like maybe the voltage regulator? I've never had to deal with that before, so I'm not sure what its symptoms would be. Any ideas would be appreciated.

 

The regulator should be built into the alternator.
Check for bad connections.
Check for loose belt.

 

Make sure the alternator is working. I've bought more than one bad alternator from Autozone. One failed in 24 hours, the next one lasted a couple weeks. The third one was the charm, and it has been working for a year now with no problems.

 

Thanks for the replies. The belt is tight, the connections are good as far as I can see. Just wanted to check and see if there was anything else I needed to look at before I pulled the alternator off again.

 

You need to find the charge wire from the alt in line is a grey or black molded rubber block. Inside is the fusible link. It may have burned up. You then need to figure out why before you replace it.

 

Wouldn't it completely quit charging if that fusible link burned up?

 

I've been having the same problem. did you end up fixing it? if so, what did u do to fix it?
I've gone through 2 batteries and 3 alternators and my battery still won't charge.

 

Clean, check replace battery cables. These may look good; but can corrode internally. Clean ground cable connection point at engine block; and smaller ones at radiator support and firewall.

 

Thanx for the info. I took my truck into an automotive electrical specialist after trying everything and it turns out there was a broken wire somewhere in the headlight circuit that was somehow causing a short and not letting the battery charge, or at least that was what i was told... Something that i had neither the patience or the time to find. not a bad deal either, 60 bucks an hour and it only took the guy 2 hrs. to find and fix the problem.

 

Another thing to check is if you have aftermarket pulleys? Mine was a 4" one on the crank and unless you were keeping the rpms up it would discharge. Put a 7" stock pulley back on and ththe right size belt and everything was fine.