Alternator voltage at idle

[reverett]

Ok, I have an 84 K5, relatively stock to my knowledge. After doing some research and searches on this site I tried the recommendations of testing the charging system with a multimeter, here's my results followed by a question or two...

Motor off, voltage at Battery 12.60 (OK)
Motor running fast idle 14.30V (OK)
Motor running fast idle, everything on 14.30V
Motor running reg idle 500-600 rpm, everything on 12.60V
Motor running reg idle 500-600 rpm, I turn everything off 12.60V

So I run around to the cab and give it a little gas...
Motor running reg idle 500-600 rpm, everything off 14.30 V
and it stays there until I turn everything on then it drops...

So my question is, is this normal? Or is something wrong and if it's wrong is it my voltage reg inside the alternator? Or would a higher amp alternator help when at idle?


BTW... for those who probably freeked out when you saw your in dash voltmeter drop to what you think is 8 volts, mine was there but the multimeter read 12.60 V.

Thanks!
Rob...

 

[neverendingproject]

You need to set your idle a little higher. The alternator wont kick in till 750 rpm or so.

 

[Dallin]

Your results aren't that unusual. I'm guessing your alternator is a 10si. Upgrading to a CS140 would probably keep your voltage up at idle. There are plenty of posts on how to do it.

 

[chevyryan]

well if its a 350 you definately need to set the idle higher, that might help