just replaced the alternator in my 79 truck and its still not charging the battery...does it have to do with the voltage reg? im not familiar with these motors at alllll i just got the truck about week ago. not sure if this is a noob question or not.... any help would be appreciated

 

Well what was it doing to cause the problem in the first place ??

Did you have the old Alternator checked before you replaced it??

It could be almost anything on a truck this age as you stated bad voltage regulator or a bad ground maybe the wire from the alternator to the regulator is fried or the one that goes to the fuse block .

Corroded battery terminals or any other connections.

Break out the Multimeter and start checking.

Good luck

 

It is good practice to replace the voltage regulator when you replace an alternator. Visually check wire conectors and wire for tight connections or damaged wires. Check your fuseable links on the positive battery terminal, check all wires from the alternator to the voltage regulator, from the voltage regulator to the battery, etc. Use a voltmeter, no battery power and check wire resistance. Check all ground connections. If you have any corrosion around any connections or in the plug in connectors, use CRC Electrical cleaner and a copper wire brush to clean the connections. Hope this info helps.

 

change the voltage reg and it still wasn't charging battery. i used my multimeter to check around. alternator was putting out but not getting to bat so i changed the corroded terminals on the + side. pretty much fixed it.... its still only running around 13.4... probably just need to change more terminals. thanks guys