Alternator light after starter replacement.

[MaconPaul]

I replaced the starter, replaced AOS with a UAOS, removed alternator for access. Also replaced 3 pulleys, water pump, thermostat, all engine bay hoses. Spark plugs, coils, and added 3rd radiator.
The idle is a little rough but no check engine light.
My imagination is hearing an electrical whirring sound in the cabin but don’t hear it in engine bay. And getting an alternator/battery error. The battery has been on a tender. 
Where to start? Did I screw something up?

[jchapura]

12 minutes ago, MaconPaul said:

I replaced the starter, replaced AOS with a UAOS, removed alternator for access. Also replaced 3 pulleys, water pump, thermostat, all engine bay hoses. Spark plugs, coils, and added 3rd radiator.
The idle is a little rough but no check engine light.
My imagination is hearing an electrical whirring sound in the cabin but don’t hear it in engine bay. And getting an alternator/battery error. The battery has been on a tender. 
Where to start? Did I screw something up?

What are your voltages? Resting, idling, driving above 2000rpm? There are gizmos to help with this monitoring - Antigravity Batteries has a battery tracker. Others plug into the cigarette lighter.

Do you have any codes (can be read with Durametric and other (OBDII) readers)?

I've read stories on Rennlist about induced electrical noise in the sound system even when the sound system is not turned on. Might your alternator be damaged or no longer have a high quality ground? Could the noise be mechanical (transmitted noise)? You did change pulleys. Run the car a few minutes without the serpentine belt and see if the noise is reproduced. 

 

 

 

[JFP in PA]

1 hour ago, MaconPaul said:

I replaced the starter, replaced AOS with a UAOS, removed alternator for access. Also replaced 3 pulleys, water pump, thermostat, all engine bay hoses. Spark plugs, coils, and added 3rd radiator.
The idle is a little rough but no check engine light.
My imagination is hearing an electrical whirring sound in the cabin but don’t hear it in engine bay. And getting an alternator/battery error. The battery has been on a tender. 
Where to start? Did I screw something up?

I'd start with checking the alternator, is it putting out 14.5 V DC at idle?  If not, I would check to make sure you properly reconnected the wiring.

[MaconPaul]

I’m getting 12.4volts now, 13volts earlier with car off. 12.3 with ignition on and 12.05 with engine running measured at the battery 

[JFP in PA]

2 minutes ago, MaconPaul said:

I’m getting 12.4volts now, 13volts earlier with car off. 12.3 with ignition on and 12.05 with engine running measured at the battery 

 

Your alternator is not functioning, running you should have 14.5V DC.

 

Pull the alternator, check the wiring connections to be sure they are tight and seated, if they are you are in the market for a voltage regulator..........

[jchapura]

1 minute ago, MaconPaul said:

I’m getting 12.4volts now, 13volts earlier with car off. 12.3 with ignition on and 12.05 with engine running measured at the battery 

That's trouble. Recheck connections. Use Deoxit on the plug-in connectors. Use fine grit sandpaper (and clean off the grit left by sanding) on the nutted connections. Is it possible you shorted something out as you removed the battery? Were the battery cable ends removed at the battery? Is it the original alternator? It might be possible that it's only the voltage regulator module.

[MaconPaul]

My first step was to disconnect negative battery terminal then positive before I started the project. 

[JFP in PA]

6 minutes ago, MaconPaul said:

My first step was to disconnect negative battery terminal then positive before I started the project. 

 

That is correct, and not the cause of your problems...........