voltage and electrical issue on my 88

[benoit454]

ok here's what's going on...

88 chevy k1500 rebuilt 350 tbi brand new battery, and now has another known good one, tested the alt. at autozone twice, passed. When we try our snapon charging system tester at the battery it reads just over 12 volts running, same as it does not running. While on dad's 84 c10 with either battery mentioned his runs 14.5 or so volts while running.

So, what I gather so ar the batteries are good either one of them, the charging system tester is working, my alt. passed the test twice, so somehow somewhere something in my systyem is messed up.

My alt. works but is not getting power back to the battery? if so how and why?

Maybe loose wire causes this? bad ground or unhooked ground?

sensor?

The thing ran fine, no issues that I know of, just had a knocking noise, turned out to be the starter spring in the bendix or whatever it's called, it was wound behind the plate it rides on and holding the gear out hitting the flexplate. I took the trans and t-case out thinking it was a bad flexplate, put it all back together and now this.

Maybe a fuse is causing this? anyone have any ideas? I have to check it out sometime but I don't get much time now.

When I first put in the new battery and started it, the gauge was bottomed out lower then 8, then it came up to around 10 or so whatever is the middle of 8 and 12 or 14, it stayed there, then when we tried to drive it went to nothing and stayed there. This was a couple days in between but nothing changed that I know of.