'98 Burb/4.7 Vortec: How To Read The Ammeter?

Just had the alternator replaced.
My sense is that the new one isn't charging enough - backed up by an occasional weak horn, a couple of sluggish starts, and a battery that reads about 12.8
volts instead of the 12.9 it was the last time I charged it.
Could also be some sort of parasitic load when the system's shut down... but it seems to me like the ammeter used to read one notch below "14" and now it's more like 3-4 notches below. (at least I'm *assuming* that it's an ammeter...and not just a voltmeter...)
Anybody know what a reasonable rate is?
--
PeteCresswell

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Ammeter reads current, in amps, Voltmeter reads volts only. Good, fast way to check the charging system is to have the engine running, turn on the high beams, blower on high, wipers on fast,ac at Max. Voltage across the battery, at the terminals, should be about 13.8, with a good belt, and alternator.
Just my 2cents worth!

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On Thu, 03 Aug 2006 02:34:14 GMT, "Andy & Carol"

Not bad but actually voltage varies with tempature.. On a cool or cold day at startup in might show 14.5 to 14.8 volts or more but on a very hot day with a hot motor it might only show 13.0 to 13.2. ----------------- The SnoMan www.thesnoman.com
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Per SnoMan:

Then it's right on the money with today's heat and I'm looking for some kind of parasitic load... which, I think, I've found.... Got this little adapter to power my iPod and send the audio to the dash head unit. Turns out that even with the iPod detached, the thing is drawing current. Not a whole lot to be sure... but I'm going to charge the battery one more time and just take the adapter out of the car (to make sure I don't forget and leave it plugged in...) for a week or so and see how the battery charge holds up.
--
PeteCresswell

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Please!!! This is not rocket science...put away your your high fluting digital voltmeter!! 14.00000 volts is good enough!You are just trying to confuse things. 4 cents worth..

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Per Andy & Carol:

Is the gauge on the dashboard reading volts or charging amps?
I get 13.2 volts across the battery terminals with high beams, ac at max - just after alternate/serpentine belt/tensioner replacement.
Went back and checked again with all of the above plus wipers on max and got 12.9.
Turned the wipers off, and it slowly climbed to 13.0... but didn't get back to 13.2.
Is there a charging rate adjustment somewhere?
--
PeteCresswell

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wrote:

You are fine in hot weather this is about norm and no cause for concern. Also your alt doe snot make max current at a idle so civen enough load at a lidle the voltage will sag a bit and them pick back up as RPM increases (around 2000 engine RPM (give or take) alt pretty much reaches full ourput ----------------- The SnoMan www.thesnoman.com
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