Charging Question

[oo7thenova]

yesterday I noticed that the Volt gauge on my 5.0 was almost getting to the red, this was a idle ,so Today I bought a new battery. The new battery help very little.

I read on previous post on how to test your alternator, which said to disconnect the positive terminal from the battery while the car is idling and if it stays on , that means the alternator is good and if it dies that means the alt is bad.


So i tried that method and the car died.

can anybody shed some light on this.



It hasn't killed the battery yet since the previous installed a new one.

 

[shallchr]

Looks like a bad alternator or a problem with the alternator harness. The battery is for cranking the car and alternator handles the rest of the work. You can have a local auto parts store test the alternator either in the car or they can bench test it for you. The alternator is responsible for charging the battery after each crank and if the battery was going south for a while the alternator was working overtime to make up the difference. As for a replacement alternator I quit buying remanufactured and went with a new unit. They cost more, but I have had fewer issues with them. Also if you are running pulleys you will definitly see lower voltage at idle as the aftermarket alternator pulley is standardly smaller and requires more revolutions to outut the amps as the stock pulley.

 

[HISSIN50]

shallchr is right. it is worth mentioning that a bad battery can make it seem like the alternator is bad (if the plates are bad, the charge in essence doesnt make it into the battery). you have eliminated that possibility. go get it checked for free at parts store (leave it in car for at least the first test. no need to bench test yet, IMO).

you can hook a VOM to the alt wire and see what the voltage is. then check battery. if there is a big drop, that suggests the wire is gone (from alt to batt junction. called a drop test). often overlooked, but some cars see a drop of over one volt. unacceptable.

good luck. let us know what you find. if you get a parts store alt, make sure they bench test the NEW/rebuilt alternator for you before you leave. as shallchr said, they can be troublesome. i have bought more than one alt, batt, and starter that tested bad from teh store. i have all such parts bench tested before i buy it/them.

good luck.

 

[Michael Yount]

Most parts/battery places (AutoZone, PepBoys, even Sears) can do a load test on your alternator with it still in/on the car - like Hissin' suggests above, drive on by and have them test it. It's the easiest way to know for sure if it's charging properly. And Hissin's advice on having the new one bench tested right out of the box before you leave the place is a good idea. A lot of folks upgrade to the 3G 130A alternator when they replace - you may want to think about that.

 

[oo7thenova]

Yeah its official. My alternator is toast.

i had one of the guys at kragen's test it for me.

so now i'm going to try and get the 3g kit from pa-performance

any pointers on how to install it?

 

[Michael Yount]

Pa-Performance's installation instructions are the best in the business. Just follow them. And I recommend getting their upgrade kit with the 4 or 6 gauge cable to the battery. You don't want to take a chance overloading the stock wiring system with an alternator that's capable of putting out 2 to 3 times the amperage of the stock unit.

 

[HISSIN50]

Pa-Performance's installation instructions are the best in the business. Just follow them. And I recommend getting their upgrade kit with the 4 or 6 gauge cable to the battery. You don't want to take a chance overloading the stock wiring system with an alternator that's capable of putting out 2 to 3 times the amperage of the stock unit.

yeah, what Mr Yount said. LOL (im brain-dead after installing keyless entry, remote starter, etc on the g/f's car all day).
im too poor for the pa stuff, so i will likely use an alt from a SN95 when mine dies. the wiring info from Michael is right on. once you get all the stuff you need TO DO IT RIGHT (some have done it for cheaper, but havent used all the things included in the kit), you will be real close to the kit price.

you may need to do some grinding on brackets to make it fit (i assume not so on the pa stuff, since it' s not poo. i believe Michael runs one (cant remember if you have the starter, alt or both. i know you have one or more). there are many sites with generic 3G instructions.i would suggest doing a search in here (not trying to be a pain, but that will be more thorough than me rambling). i have many on hand, so if that doesnt work, lemme know through posting or pm (posting is better, as i havent been in here much), and ill post the url's. good luck. remember not to remove the stock wiring from the alt to the solenoid, just add to it (there is a resistor, etc in there that is necessary). Jrichker once mentioned running another ground strap as well. i never have confirmed whether this is necessary (im sure all you need to know is covered in PA's instructions as Michael said; i'm just rambling since i havent seen the instructions). enjoy the new power output.

 

[Michael Yount]

Pa-Performance's instructions are complete with detail on how to modify the bracket so the 3G will fit - as I said, they are complete. They also sell a 2G in a 95A version (stock is 65A) - that's what I run. It doesn't require any grinding on the bracket to fit.