Im haveing a problem with my alternator. the auto parts store told me that it was bad so i bought a new one. now that i have the new one in they are still telling me that it is bad. I think it might be a short some where becaue it is only putting out 30 amps instead of 90. If anyone knows what might be wrong or has had this problem advice is much appriciated.

 

I would not be surprised if the new alt was bad out if the box.

Check all the wiring coming from and going to the alternator and your battery.

 

Do you own a voltmeter?

 

yes I do

 

Wait you are in houston, where in houston I have a good friend there that can help you.

 

I wouldn't be surprised if the new one is bad either. It happens quite frequently with alternators actually..............

What VOLTAGE is it reading at the battery with a voltmeter? (and also on your voltage gauge on the dash) Should be in the 13.5 - 14.0 range if the charging system and battery are working properly

 

Im located in south houston clear lake webster area

 

reading 12.5ish at the battery and like 12.5 on the meter when i start it but after a few minute it drops suddenly to 9(all the way down)

 

An alternator will only generate the current that the regulator tells it to. If you only need 30A, you're only going to get 30A.

In order to generate 90A, you're going to have to make sure you're drawing 90A - either with a dummy load or actual electric loading from vehicle systems.

 

the 30a is a number i got from the auto parts place when they tested it when it was n the jeep. i also got it tested off the jeep and it put out 90a so i think that it might be the feild regulator