some one help me out !!!!!!!!!!!!!!

[454muscle]

This is really a simple issue.
1. Connect a voltmeter to the + and - of the battery. Start the car.
2. See if it maintians over 12 volts. If not, it's not charging. Find the break (bad ground, bad terminal, etc.. check one by one to the alternator).

If you don't have a voltmeter, hook up a small light bulb to the + and - batt. terminal. Start the car, watch it dim. If it dims and does not get brighter esp. when you rev it, it's not charging. Go to step 2.

If it IS charging then your battery could have bad cells. Try another one.

 

[84cutlass454]

cool man thank for the info really appreciate it. I will try that when it get back to warmer weather here in ohio lol

 

[megaladon6]

Actually the alt should run around 14v

 

[84cutlass454]

cool i will defiantly look in to it. i am young and still learning lol. love the help every one and by the way i pulled back the plastic covering for the wires come out of the firewall. i found i purple wire its not wired to nothing....... i am going to check and see if it hot when in the run position tomorrow thanks again fellas ..........Matt

 

[84clonewars]

Hi, I had a similar problem with my 3rd gen Camaro, after a sbc 355 and complete gauge swap I couldn't get the alternator to charge my battery. Come to find out when I did the gauges I didn't hook the two wire alt. up correctly, one wire should go directly to the battery and the other should go to the volt gauge to send the signal to the alt. for charging the battery. If you have after market gauges it should say signal on the back of the gauge atleast my autometer ultralite does. I hope this helps you man good luck getting your ride back on the streets.

 

[custom442]

Once you charged the battery after it died, could you drive the car around the block again? Or at least start it and run it for a bit?

If your car is dying off battery charge and the alternator tested good the first place to look is your alternator and how its wired. My bet is you don't have it wired correctly.

A 3 wire alternator should have:

1) a thick (10 gauge) hot wire from the battery positive terminal to the alternator back post. If your battery is mounted in an odd location, use the starter +12v battery wire. Not a switched source. A fusible link here is a very good idea, even more so if the back terminal is in close proximity to any metal from any grounded source.

2) a switched, ignition hotwire (smaller gauge 14-16 gauge) to the the alternator switch. Usually the top of two side posts if you don't know which terminal is which, go back to the auto part store where you tested it and ask them . Sources to use here are your coil/ignition hotwire, or choke hotwire, a switched +12v. This wire turns the alternator on, and is where I believe your problem is.

1 & 2 are the minimum requirements for wiring a 3 wire. but keep going ->

Next, wire up ground and voltage sensor:

3) a good sized 10 gauge or thicker GROUND (-) directly from the battery, on a bracket bolt holding the alternator in. On cars with lousy grounding circuits this wire loops the alternator directly with the battery, even if its a nice new frame-off still ground the alternator don't trust engine ground.

4) a 10 gauge wire from the voltage sensor terminal (second/lower post of two side posts). This wire is not necessarily needed, but it does help. for example your lights are dimming or some power accessory is slowing and you need more voltage through the system so those parts will receive full 12v and your battery will be over-charged, this wire should be wired from its terminal closer to where you need the extra voltage. Many people wire this to the hot post on the back of the alternator or if there is a hot post on the firewall, neither are wrong.


there is an incorrect way to wire a 3 wire which acts as a generator and bypasses the voltage regulator. This works if there is a short path between the alternator and battery, but it is not ideal and when the battery runs low your car dies faster than with alternator. Post pictures so we can see your alternator wiring.


There are many other reasons it could be dying but this is the first step

 

[custom442]

Hi, I had a similar problem with my 3rd gen Camaro, after a sbc 355 and complete gauge swap I couldn't get the alternator to charge my battery. Come to find out when I did the gauges I didn't hook the two wire alt. up correctly, one wire should go directly to the battery and the other should go to the volt gauge to send the signal to the alt. for charging the battery. If you have after market gauges it should say signal on the back of the gauge atleast my autometer ultralite does. I hope this helps you man good luck getting your ride back on the streets.

the alternator has a voltage regulator in it. There's no need for a voltage gauge. What you did was hook up the regulator's sensor wire to your volt gauge so the gauge reads the output of the alternator, not a bad idea but not necessary in any case. Unless you hooked up the alt 'on' wire to your volt gauge, then that would've been an ign on from the gauge hotwires, probably what you did seeing as it 'worked' after you did this..

 

[custom442]

Actually the alt should run around 14v

depends on the circuit really, different cars/loads/times/temps/surroundings will run more or less voltage. as long as he's running over 12v. The voltage regulator attempts to run 14v from the point of sensor or alt power, which doesn't always mean its running 14v

 

[79loserbluebu]

The way it's wired from the factory is the voltage light completes the ground to the voltage regulator circuit. I had this same problem on my 79' Malibu after we wired the MCSS cluster in.

Check for Ign 12V at the red wire for the alternator. If you don't have it, temporarily tap into the distributor wire with a piece of wire to verify the repair. After that, rewire it correctly.

 

[custom442]

The way it's wired from the factory is the voltage light completes the ground to the voltage regulator circuit. I had this same problem on my 79' Malibu after we wired the MCSS cluster in.

Check for Ign 12V at the red wire for the alternator. If you don't have it, temporarily tap into the distributor wire with a piece of wire to verify the repair. After that, rewire it correctly.

if he has a 3 wire internal regulator there is no need for a remote ground. A ground from the battery to his alternator will be better.