86 Monte Carlo charging and cluster issue

My Monte Carlo LS was a fuel injected 4.3. I put my 350 in with a known good alternator and did my swap to ss gauges which I am still working some bugs out. I noticed there is no charge light bulb. When I fire it up the voltage gage stays at battery voltage and the alternator does not charge.

What excites the alternator to make it charge since there is no bulb. Does the brown wire go back to gauge. My Cutlass has gauges and a charge light and every older car I've had, had a charge light. I even read on the Malibu racing cluster conversion that it says to unhook the brown wire from the alternator

Also when the key is on, the tach sets to 0 but when fires it spins all the way around to a 5 o'clock position . Tried with a filter and without and no change

Any ideas

pagrunt said:

So I'm going in the right direction, the warning light cluster was swapped for a gauge cluster. The factory gauge Chevy's had a brown resistor wire running from the C100 to the orange wire in the ignition switch plugs to replicate the resistance the volt light's bulb gave. An option is to repurpose the Check Engine light into the volt light & all could be good. If you still have the #25 circuit wire in the cluster plug , just depin it & move it to the spot where the #419 circuit brown/white stripe wire is & then that will convert it the volt light. To be honest, when I first converted my dash I never knew this & never ran into any charging issues. I don't understand why Chevy's never had an independent volt light like Pontiac & Olds had.

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When I get back to the car this week I will try that and see what happens. My number 25 is still in the harness as the diagram shows it in there . I did depin the 419 as I took the computer out and didn't want the check engine light on all the time

Found the brown wire had been cut under the brake booster. I soldered them back together and alternator charges now. Will probably order another tach eventually as I believe it is a tach issue