Electrical Problem

[68sunlitgold]

I need your help with a problem I am having with my coupe. I have been having problems starting my car for the past month. It started with a dead battery, the battery was less then 2 years old, so I assumed it was the alternator (it was the original 40 year old alternator) so I brought it in and it was working but not putting out a full charge, so I replaced it. That did not solve the problem so I brought in the battery and was told it had an internal short so I replaced it. That worked for about 4 days until the battery was dead once again. I recharged it but had the same problem. I then figured it was the voltage regulator, so I replaced it, again recharging the battery, 3 days later I had the same problem. I have looked at and cleaned off both the engine, alternator, and battery grounds but still no solutions. Once I jump the car, it will run and I have placed a wrench at the back of the alternator to see if it is working (if a metal object is attracted to the back, like a magnet, the alternator is working), but it will not charge the battery. Since my car is a daily driver and it is usually dark on my drive home, I usually have to turn off everything in the car except the headlights (which get very dime) to make it home to recharge the battery. Does anyone any other ideas? Thanks

Doug

 

[Midnight Special]

...I once had the same exact problem and it t
turned out to be the wiring harness connector that plugged into the regulator. It visually looked good, but the wire crimpings were oxidized... Did you verify it was charging with a volt meter?
13.5-14 volts??

Steve.... Rob...?

 

[robert campbell]

Doug,
First thing I would do is charge the battery back to full out of the car on the bench. After you feel it has a full charge, remove the caps from the battery if they are removable to let any “gas” (hydrogen) vent. If you have a fan or something let it gently blow on the battery for a few minutes to get any gas out. I had a battery blow up in my face installing it once. Very horrifying and quite a large messy explosion. Not to mention I was bent over putting the ground cable on and got a lot of acid in my eyes and face. All is good, but I have new respect!!

Now put it in the car and hook the positive lead up. Now when you try to put the ground lead on, do you get a slight spark? That indicates a slight “draw” on the battery and should not be present. Now if you have a volt ohm meter you can hook it between and measure the draw. My guess is that is small, but measurable. You have something on or a short to ground.

If you have nothing of the sort, then go back to the alternator and voltage regulator. I have came across either one being defective.

If you have a slight draw, post the electrical options on you car. And anything like amplifiers and such. I am sure Steve and Neil will weigh in! They are “electron” heads!!!

Remember, DC stands for "damn confusing"!!!

Rob

 

[rvrtrash]

If you have a factory clock, aftermarket stereo or alarm system on your car, there will always be some voltage draw but to drain as fast as you describe, something else is going on. You will need a voltmeter to troubleshoot this. With the battery fully charged and "nothing" on, you should read 12.6 volts. Take a reading with the ground cable off and if it's correct, hook up the ground. It should stay about the same. Start the car and take a reading with nothing on and then one with your lights, fan and wipers on. It should be 13.5-14.5 volts running and not drop below 13.0 with everything on. Some other things that can cause a charging problem are a loose, slipping fan belt or an alternator that is too small. 35 amp seems to be what everyone buys but I wouldn't go below 42 amp and if you have a stereo or something else, look for about 60 amp. They're more expensive but worth it. You might try replacing the condensor (which is really a capacitor) at the voltage regulator also. I might be creating a high resistance short to ground. When you get this far, let us know what you've found and we'll go on from there.

Steve

Hey Rob, your DC comment reminds me of the old "definition" of FM. It's Frequency Modulation of course but we always called it F***ing Magic.

 

[franklinair]

Be sure the engine block is properly grounded to the frame/chassis. (Remember, the alternator is mounted on the engine, and the Ground path must be completed between the engine & frame.) Another consideration - how's the starter??
Neil

 

[robert campbell]

Neil is all over it!! I install very big "non-stock" ground between the engine and the frame on my cars. If you have a problem it is almost always a ground!!!

Rob

 

[franklinair]

Any resolution to the electrcal problem?
Neil