SBC Alternator Wont Hold Charge

[Donks 10+ year member]

i have a 305 v8 SBC. the 0 gauge wire in the trunk was touching the chasis which started screwing with the alternator voltage yesterday, by the time i noticed it was dropping/not charging it was too late. i removed the 0 gauge but the problem still consists. Today Replaced the Alternator with a brand new one and Charged the Battery and still got the same results. when i cut it on it'll stay around 12-13volts when it should be 13.5-14.4volts constantly. My Voltage Usually NEVER Drops below 12.7-13volts. when i hit the brake or turn on the headlights my voltage drops to 8-9.5volts. while im driving it just jumps up and down from 8v-13.7volts it never stays steady. it usually always stays at 14v. ive been to plenty of shops today and they want to charge me a arm n a leg just to fix what im assuming to be a simple problem. ME MYSELF i believe its a wire that has shorted or burned somewhere OR the Voltage regulator is going bad. ..please let me know what you guys think..cause im stuck

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[LBC]

Alts don't "hold" a charge. They generate the charge. You need to test for a short somewhere first (most likely not it if your car routinely starts) and then replace the alternator.

 

[Donks 10+ year member]

i believe the having a short part somewhere maybe right because i already replaced it with a new alternator today already

 

[dbjunior 10+ year member]

How tight is your belt new or old?

 

[Whytellyou]

Get a new battery.

 

[frogcase2002 10+ year member]

What are you checking the volts with. Could be that that's messed up.

 

[Donks 10+ year member]

i found the problem you guys. all it was was the ground for the battery wasn't tight enough. i guess the retard who sold me this car didnt tighten it....thanks you guys. for surely didnt want to spend $150 just for a shop to tell me it was some total other BS just to gyp me for $150 when it was just a loose ground...lmfao