wood_e

So When I installed my Reman'd alternator my voltage at the battery was:

Running - no headlights/AC: 13.8v
Running with AC: 13.4v
Running with lights: 13.4V
Running with lights/AC: 13.1v

Now it's:

Idle - 12.7v
AC on 12.4
Lights on 12.4
Lights + AC - 12.2-12.3

What's weird is that when I check the voltage at the alternator with the car on it reads like this:

Large post: 13.8v
Small post: 14v
^perfectly normal numbers!

So what could be the problem here? The cable from the alt to the battery? The alternator itself?

help me please...

wood_e

Battery + to alt + while running = 1.66v

plus the alt post was HOT so theres resistance there - time for a new terminal

4Driver4

Confused as to why you changed the alternator in the first place?

wood_e

the old alt was bad putting out less than 10 volts on the tester

squidix9

Go from point to point and figure out where the biggest loss is.

I got burned by that years ago. My TR7 used to have a dead battery constantly. I kept checking the voltage at the battery clamp and it was always ~14v. Then one day I checked at the actual battery post and it was around 11. A quick cleaning of the terminals and all was well.

nothing

15 minutes south of Vegas last year I had that cable melt on me at the battery end. If corrosion has traveled up the cable at all, the resistance can generate a LOT of heat. Combine that with a hot day and you can have serious trouble. I'm lucky I didn't have an engine fire.

wood_e

I replaced the alt to battery cable and converted to a marine battery terminal

Idle - 13.8v
AC on 13.67v
Lights on 13.67v
Lights + AC - 13.5v

^ much better

Thanks everyone