Just one of those days - dead batteries!

This day has been a real treat. The batteries in my truck are dead but that is not what this post is about. Tonight I found the battery in my Jeep died too. Turns out I left the ignition on for about 24 hours. I was able to jump start my Jeep but it wasn't doing much, lights were dim and the voltage was hovering around 12 volts with the engine running.

I do have a deep cycle Optima and the alternator shown. I am not sure it is a factory alternator as nothing else on my Jeep seems to be factory. R) So my question is, is it likely I fried something like the voltage regulator or does a deep cycle take longer to charge? I ran the engine for about 10 minutes before shutting it down. The voltage on the batt from just a few minutes ago was 9.5 volts.

The picture below is the alternator I run. It looks like a GM alternator with the internal voltage regulator. Most likely with my luck today, I am thinking both the battery and alternator are toast.

Thanks for the help. It is time for a .

Oh, in case you are wondering what the valve is, it is for my aftermarket heater.

 

That rig came with the Motorola alt originally. Did you pull the wires off the alt terms 1 and 2 on the top? Won't charge without them. If you are running points in the dist and if they happened to be in the closed position, you probably fried them. Deep cycle batteries do take longer to recharge.

 

If you are talking about the connections you see on the alternator, they have never been connected. I didn't remove anything last night.

 

the GM alt you have on there has to have the 1-2 plug hooked up to work..
the #2 term should be hooked to the bat. and the #1 term goes to a bat light on the dash..
they are vary easy to hook up and a great conversion to do away with the orig Motorola alternator.

here is a quick sketch of GM alt wiring



can use any 12v light just mount in the dash.. it will light up when the key is on.. and go off when the motor is running..

 

Thanks for the help on this. First off, those connectors have never been connected to anything in the 3 1/2 years I have owned it. I don't have a battery light either but I think I will work on that right away.

 

That is a 10 or 12 si GM Alternator. If it's been working all these years then most likely that alternator has a "one wire" conversion where some of the internals are changed to eliminate the other wiring. These types of conversions usually require the engine to hit a higher rpm than idle to start working (usually around 1500-2000 rpm). With the battery voltage so low and if you didn't hit the engine rpm mentioned that could be why it isn't charging. I'd charge the battery then start it and rev it up a bit and see if it starts charging. If not, then I'd look into wiring it with the diagram shown above and see if that makes a difference.

 

Thanks nickmil, I just found a link about the one wire and it must be what I have because I haven't had any problems up until now.

 

could be a 1 wire ..
the biggest advantage of the 3 wire is having a light on the dash ..
so if the alt does quit working you will know it..

 

Well, all is good now. I charged the battery and have been driving it around and my voltmeter shows 14 volts. I didn't fry anything else.

I may go with the traditional wiring configuration down the road but this is working for me now.

 

My Sixty has the one-wire with an amp-meter on the dash.
At around 1500 to 1700 the regulator kicks in and the gauge will show a charge.
That is fast idle with the choke set. Or I ease on the throttle peddle until the gauge needle jumps and then remove my foot.monkeys

Was in the JEEP when I got it.:hurrican: