Battery Died, jumpstart and ammeter pegged
 

I left my car for a little over a day with the wipers not "parked", and my battery was drained. I have jump started it and the ammeter is pegged at the 40 mark. I'm assuming that the units are Amps, and it scares me since I've put in a 90A alternator in my car (and am concerned with frying the wires).

My car is not at my house and I'm debating whether I'm going to:
1) Not worry about it and drive the car home
2) Pull the battery, charge it, and put it back in my car and drive home

I'm leaning towards #2. What do you think?

Re: Battery Died, jumpstart and ammeter pegged (Chris A)
 

The owner of a local auto electrical shop here tells me that it's really really hard on alternators, and he says especially GM alternators to use the alternator to charge a battery up from such a complete discharge. He very strongly recommends removing the battery and using a battery charger, rather than the alternator in such cases.

Don't know if his perspective is the same on the alternators in our C3 vettes, but this is what he told me about the alternator in my son's Beretta and my Grand Prix.

Re: Battery Died, jumpstart and ammeter pegged (Chris A)
 

Generally I think the Alternator charge wire is rated at 15-20 Amps maybe even up to 40 or 50 max continuous (16 guage wire?). This means you are probably exceeding it. I would expect that if you run it just for 10-15 minutes it would come down quite a bit and be OK , wire just a little hot, but I personally would go with #2. , #1 is also hard on the alternator...:flag


[Modified by Clink69, 2:26 PM 12/14/2001]

Re: Battery Died, jumpstart and ammeter pegged (Chris A)
 

Hey Chris,

Thought you might like to know it looks like I am going to be able to fit the RPM AirGap under my 69 hood. Used a drop base filter and it fits. 3/8" on top. The primary side is too close to the cleaner lid so will remove the choke and grind down to the height of the secondary to give it more flow. :flag

Re: Battery Died, jumpstart and ammeter pegged (Chris A)
 

Go ahead and drive it. The battery will only take that high of a charge for a few minutes and then the meter will slowly drop. I agree, it is hard on a standard auto alternator to charge a battery from dead, so don't do it again.
My $0.02
Gary

Re: Battery Died, jumpstart and ammeter pegged (Garys '68)
 

I have a very experienced alternator guy in my building. He has always told me charging a battery that is so discharged you have to jump it is hard on alternators. Matter of fact IT IS DEADLY to the new design of alternators, exp GM. He has seen many customers come in with unoperating alternators that mysteriously died after the lights were left on and the car was jumped. The alternators in our vettes (C-3) are the old design and are much more durable. But if you can, recharge your battery.

Re: Battery Died, jumpstart and ammeter pegged (Chris A)
 

I had the same experience with a dead battery and alternator overcharging. I would suggest that either you pull the battery and recharge it or replace it if it is a few years old. It is cheap insurance against elec. problems which are a pita.

Re: Battery Died, jumpstart and ammeter pegged (R. Bruno)
 

Alternators are designed to maintain charge - NOT recharge a dead battery. Pull it, replace it with a new one of higher CCA capacity and smile!. Check battery cables while you're at it.......

Re: Battery Died, jumpstart and ammeter pegged (Chris A)
 

Don't be surprised if you have a huge voltage drain coming from your wiper motor. If after charging your battery, it dies quickly, you should disconnect your wiper motor. It's happened to me a couple of times.