Charging Problem Alternator?

[DANNYDOO]

Hi THIS is my 1st post here.I will be answering some questions while IM waiting for an answer to my questions :)

My alternator is doing nothing!

WHen i remove the neg terminal the car shuts off.I charged the batt to 12.7v.While it runs it discharges slowly down to about 10v then I recharge and continue testing.

I checked every fuse under the dash and under the hood.

CHecked the block fuses.Even opened up the block fuses and tested voltage AT THE WIRE.aLL THE SAME

Seems my gf ran something over and the speedometer and tach stopped working last week.

the dashb oard shows the battery light on when the key is on..and when its running..even if i charge it to 12.8v.

I found this interesting link how to change and test..But the diagram is hard 4 me to grasp.http://www.lextreme.com/alternator.html

I just have a feeling its not the alternatoer itself...

also...I just cleaned all the terminals and the battery today..and now the alt does nothing.

yesterday,it was showing 13.5volts when i tested it. I tested it b/c i thought i needed a new battery cause sometimes my battery would be realy weak and couldnt start the car back up.

I JUST HAVE A FEELING MY CLEANING THE TERMINALS DID SOMETHING....???help.

[steve2006]

If the battery is not being charged and the no charge light is on it has to be an alternator problem,there is nothing else that charges the battery,there is a 120A fuse in the engine bay fuse box but when this blows it normally gives a blank dash as well.

If you do a little research you will find the alternator is often damaged by leaking power steering fluid from the pump above it and the cure is to replace the reservoir O ring and replace the alternator.

BTW disconnecting the battery negative whilst the engine is running may damage the alternator diode pack and regulator.

As for the non working speedometer check the 2 speed sensors and the wiring located on the transmission as one of these drives the speedometer.

[DANNYDOO]

Steve,thanks

Changed the alt after testing everything i could find.And shes runnin like a champ!! 14.4v with full load .Battery never spun the engine so hard since ive had it. BTW yes it was saturated with oils!!! old and new...

also....M SPEEDO WENT OUT WITH MY TACH..THE speedo was off by 15mph for months...my gf said she ran something over then both the tach and sppedo were dead 2 days later...will check the botttom speedo cable...but the tach????????????

[curiousB]

You better fix the PS pump leak that ruined your last alternator or you'll be needing a need alternator pretty soon. Many posts here about PS fluid damaging alternators.