voltage low after new alternator

[rockyklg]

hey all, will try to keep this short.
about 6 months ago i r4eplaced my battery with an optima yellow top. my old battery had worn a hole through it. ever since then it seemed my voltage has become worse and worse till the other day when i was not getting any charge. i made it home running at about 9 volts. alternator was putting out 11.2 volts at 2000. today i installed a reman alternator. installed 8 guage wire direct to batt pos from b post. kept old wiring as well and i am running
12 volts 650rpm
13.0-13.8 at 2000 plus
with lightsw and wipers cuts down to 11 or so.
checked with volt meter at idle and 2000 rpm
everything seems fine but i just dont remember it being this low before. any ideas at what else it could be? is this normal? on a side note where does the stock alt wire go to?? it seems like it goes through the firewall.
thanks

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[dfmorse]

This is NOT normal. Charge voltage should be 14.2>15.0 volts. The voltage will normally level out to around 13.8 if the system is working properly.

Check the belts, may be loose. Have the alternator checked in a shop; u could have a bad one.

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[PhilC64]

Check for a short in your accessories that you run. Lights, wipers, carb fan, etc. if the alternator turns out to be ok. Something is taking a draw on your power.

 

[rockyklg]

thanks for the responses. so what is the best way to check for a short? and if there is a draw will i be able to see it on the battery with the treuck off? checked the belts and they are tight.

 

[Wile E Coyote]

1st off, upgrading the charging wire was an excellent idea.
I can't see where this is a short, or a 'draw on your power'. Have the alt/voltage regulator (VR) checked. If they're good, then you need to find where the VR senses the system voltage. If this sensing wire or it's connection is bad, the VR will undercharge.

 

[rockyklg]

Thanks again for the help. cleaned up the connections for the sensing wire and light wire and the alt is now putting out 14.2-3 and i am showing a strong 13.8 at the battery with lights on. i appreciate it!!

 

[Wile E Coyote]

Thanks again for the help. cleaned up the connections for the sensing wire and light wire and the alt is now putting out 14.2-3 and i am showing a strong 13.8 at the battery with lights on. i appreciate it!!

Booyaa!