car dead->put new alternator in car starts: 3 days later dead again

[JoeC5]

Hey whats up guys. Last saturday my truck went completely dead when I turned the key. I put a new alternator in and everything powered-up fine. Didnt even have to charge battery, started right up. Now today truck went completely dead agin. Whats wrong with my truck??? Thanks

 

[FMExplorer]

Joe,
Tough call - if you didn't need to charge the battery chances are it wasn't the altenator to begin with. I assume everything is dead - lights, radio, hazards and so on. If so, it sounds like a faulty connection or ground. I would check your battery cables and connections, clean them and make sure they are tight. Also - take a multimeter and check your voltage across the battery. <12 is bad when not running and < 13 is bad when running.

Jon

 

[offroader_69_me]

Originally posted by JoeC5
. Didnt even have to charge battery, started right up. Whats wrong with my truck??? Thanks

This is known as alternator death, not too sound like a smart-a$$ but next time read the instructions, a uncharged battery causes the alternator to "learn" that voltage which confuses(lack of a better word) the alternator resulting in death, have your battery fully charged and tested if it is ok then I would say replace the alt and make sure the battery is FULLY charged

 

[JoeC5]

Its not the battery. It fully charged and the connections are fine. Its strange, I returned the new alt, and exhanged it for another one. Put it on this morning and truck started right up. Its so weird.

 

[newbz]

I had a similar problem, battery would drain, i'd charge it, and it'd last 3 days. Took it to a mechanic and all I did was open the hood and he asked me if it had been lasting me 3 days between full drains. He told me right away it was the battery, we checked the alternator also and it was good, went and got a new battery, fires up fine, no drains or anything and it's been 3 days. I was using an Exide battery and he said that those batteries tend to good bad real quick and the sides of the battery were bulging out and he showed me all this. Everyone I talked to said it was the alternator first thing but it turned out not to be. So it COULD be your battery i'd have that checked out.....certainly don't rule it out though. It was the last thing I would of thought.

 

[mecforyou]

You didn't need a Alt and never did. Your battery is fine too. Your truck didn't start because the power isn't able to get from the battery + term back to the - term. Do you have lights when it wont start? if not start wigleing wires at the batt to the starter sol and then to the main power box. check the grownd at the battery and on the eng block. if you have lights you may have a bad sol or starter but check for power at the small wire at the sol and if you have power there is it coming out the wire to the starter? Then check the conn. on the starter and if thats good replace the starter.