Battery or Alternator

[Deerhunter30]

I'm having some electrical problems and cannot decide if the battery or alternator need to be replaced. I was out of town this weekend and when I tried to start my Jeep Sunday it would not start. The interior lights would not even glow. It is possible that I left the interior lights on, but I am not sure. I jump started it and now it only shows 12 or 12.5 on the volt meter. I ran it for about thirty minutes this morning and still showing only 12 or 12.5. I cannot decide if the alternator is not putting out enough or if the battery is bad. What is your guess?

If it is the alternator is bad, is there a reasonably priced upgrad for my 83 CJ7? I was wondering if there was a better alternator that would bolt up and boost the output some. If there is a better alternator, what vehicle did it come on? I would like to be able to go into the local parts store and tell them I need an alternator off a ?????

 

[wm69]

Take your battery off the jeep and charge it with a battery charger. Put it back on and see what it looks like then. Check the battery cables (clean the ends). If you do still need an alternator I got a 135 amp alternator from www.alterstart.com for $60 that works good, but when I turn on all my accessories (2 sets KC's, headlights, defrost) i'm running right at 12 volts, so I wish I'd got the 180 amp ($129.00 and you have to replace a wire with a heavier gauge). At any rate, if you arent' running a bunch of lights the 135 is better than stock and not real expensive. Oh and if your battery is toast get an Optima. I know they're expensive, but my first one lasted 5 years (hard use too winches, lights, starting problems due to crappy carb etc), and I still got $25 credit towards another one (they have a 6 year warrenty/ prorated).

 

[graewulf]

A few Pics from wheelin in Slade, KY

when I need a higher amp altrnator i'd take it to the local starter/alternator shop and tell them what amperage I need it to output and they will custom wind it to put out what I need...

 

[avyoung]

If you are not sure run down to the local auto parts store and they will usually check for free and tell you which one is bad. Then you do not have to guess.

 

[Bounty__Hunter]

when I need a higher amp altrnator i'd take it to the local starter/alternator shop and tell them what amperage I need it to output and they will custom wind it to put out what I need...

That'll work on Delco alternators that earlier Jeeps used, like CJ's and earyl YJ's. Won't work on later model jeeps with the NipponDenso alternators.

Click HERE and you can rebuild your own alternator to put out up to 105A for under $35. I did it, it's simple.

 

[Deerhunter30]

I went by my local Auto Zone and everything looks good. It appears that I left the interior lights on and it drained the battery. After charging it for a while I guess it is OK.

 

[chinard]

I went by my local Auto Zone and everything looks good. It appears that I left the interior lights on and it drained the battery. After charging it for a while I guess it is OK.

That'll learn ya!!

On that subject, i have seen contol modules for lights and so forth from both quadratec and jcw that allow you to set an "auto shut off" time for each of the control lights. I might just do that for myself sometime cause i've done the same thing...

As far as the alternators, from what i've seen, all of th older model jeeps particularly CJ's have underpowered alternators.
Either get a new one or rebuild yours with a bigger core. Its an easy job, i've taken my old one apart a dozen times before i just said screw it and bought a 150amp powermaster...
Even with the powermaster i had some problems because the battery terminal lead bolt came loose and i had to take it apart to tighten it.
The only tip i can offer if you are going to perform any alternator surgery is to get yourself a long, heavy guage sewing needle to slide into the little hole where the bushings are to keep them in place while you take it apart.