hey guys i need help

i have some kind of voltage draw that killed my battery. i checked the alternator and i was only getting 13 volts at best so i went to auto zone and got a rebuilt. i installed that one (had to replace the 3 wire plug on wiring harness per mfg instructions) and now i have no charge. take it back to auto zone and it works fine on the test machine. reinstall it and redo all the splices to the new plug and still no charge. What do you think is wrong. the new plug fits exactly like the old one i am running out of ideas.

 

Maybe a fuse or fusable link? I am taking a wild guess here since I haven't had this kind of problem with an alternator before.

If I recall from way back, the alternator needs a small voltage applied to it in order to operate and then create the charge we expect. One of the small wires to the alternator is supposed to handle that small current. Figure out where that wire gets it's current and I'll bet that somewhere in that circuit is an open.

Other things to inspect are dirty connections, corroded wires etc.

One thing that has caused me to not charge up a battery is that some batteries get some kind of deposit on the post/clamp, almost like hard plastic or black corrosion. It is not obvious unless you remove the clamp and look. I have only had this problem once in over 30 years of driving(but then I regularly clean my posts). Use a post cleaner and see if that helps. This would be a likely cause of your problem, if you see charge getting out of the alternator and to the clamp but not making it thru to the post. Doesn't hurt to check, and if you have the tool, the cost is free and you should clean the post periodically anyway.

Good Luck.

Jim Henderson

 

Does it have a seperate voltage regulator? On my 84 I have a problem with frying voltage regulators. May want to check that if it does.

 

thanks guys i will check your ideas out.