Alternator repair

[Tony Radford]

When I initially start her up, the needle moves well into charge territory and seems to be working for a minute or so and then it drops back to zero. Normally, it stays a little in positive territory of the gauge just about all the time. It has been for years. If the car has been sitting up for a while, it will initially move way into charge territory just as you'd expect. None of the connections have been disturbed. This morning I re-dressed all of the engine wiring as it was running through a metal tube for appearance and I couldn't tell what was going on inside (short?) so I pulled them out and replaced the tube with plastic spiral wrap. I saw no issues. Even though is started quickly both times I drove it yesterday (short errands), the battery was dead this morning. I have no idea what pulled it down.

I'm still perplexed over the intermittent activity with the ammeter gauge. For some reason, it charges hard for a few seconds and then all of a sudden jumps back to zero. Maybe the battery really is toast. Perhaps I should take it to NTB and have a more thorough test performed. I can't imagine why it would have drained over night with nothing left on. It seems a bit coincidental that I accidentally left my lights on and drained it just over a week ago before all of this started happening combined with the fact that an alternator repair facility said the alternator was working fine.

Damn - I hate gremlins!

[patrickt]

Originally Posted by Tony Radford

Maybe the battery really is toast. Perhaps I should take it to NTB and have a more thorough test performed. I can't imagine why it would have drained over night with nothing left on.

Yes, pull the battery and have it thoroughly tested. If it checks out fine, the next step is to check for a parasitic load that is killing it while it sits in the garage. Your voltmeter is probably capable of measuring milliamperes, or you can pick up an inductive DC amp gauge if you want (see this thread for the one I use: 300 amp X 12 volt Circuit breaker ). If the battery is strong, and there is no parasitic loss, we'll move on to the next step.

[RICK LAKE]

Tony Radford Tony do you have a mini stater on the car?? If yes this only needs about 100 -140 amps to crank over the motor. Your battery could have a bad cell and still have enough power to crank up the motor. If the battery is bad with a bad cell. It will have the charging system running crazy. The voltage regulator in some cases to stop charging the system to prevent added damage to the wiring system. Take the battery to a pepboys or auto zone. If the battery is bad, go to the largest cca that is the same size as what you have now. i am still staying with a charging issue after the battery is replaced. If the power wires are in a steel tube, Cut the wiring harness out of this. I hope the wiring harness is taped inside and will not rub inside the tube. Will wait until battery is tested. Rick L.