[TheDuke276]

Have a '79 CJ7.

can't get the volts above 11.5

Battery is good
alternator is good
solenoid is good

In one case, I ran the jeep for 20 minutes, stopped for a few, then went to start it again and it was dead!

Someone told me to check the fusable link, but I cant find it anywhere! I'm new to this in some respects, but I don't think I've seen it.

any help out there???

[Geer_hed]

Ummm... If you start the engine and let it idle, what kind of voltage are you getting at the battery? If the alternator is feeding the battery appropriately, and you still think your battery has a parasitic draw, you can do a draw test and see if you have a draw, but it sounds like you're more upset about the 11.5 volts than anything. If your alternator is charging and you don't have a draw, your battery may never get above 11.5 volts, you may just have to replace it with a new one.

But if you have a draw, well, that's a different story. We'll cross that bridge if we get to it...

[TheDuke276]

I swapped out the battery with the one in my truck and got the 11.5 volts as well.

What's funny is that I dont have a radio in it yet.

But I did idle it for 20 minutes and still got the 11.5 volts during the idle.

I did put a tester on the resistor wire in a few spots, and it lit up dimmly. Even on the solenoid connector. I didn't know if that was normal!. Plus, it was a very hot wire to touch with the key in the forward position.

But it may be a draw, because I have had to charge the battery a lot.

[Geer_hed]

Ok, well then, start the engine and let it idle for just a minute or two and then disconnect the positive battery cable while the engine is still running. If the engine dies, your alternator is not charging appropriately, if it doesn't die, then the alternator just moved a couple notches down your suspect list.

[TheDuke276]

OK

I'd like to try and figure something out first that may be part of the problem.

I have a red resistor wire that runs aroudn the block. It then splices off
1 wire goes to the coil.
1 wire goes to the solenoid

When both wires are plugged in, the tester wire is dim on both lines when the key is turned forward (not started).

when I unplugged the wire to the coil, the tester light turned bright white on the wire to the solenoid.

So, could my problem be the coil?????? and if so, how do I test it???

[TheDuke276]

Ruled out the ignition coil!
Figured it was $15 and worth a try.
The Jeep does start a heckuva lot faster now.

But still not getting 12 volts.

also, did the draw test and the tester light did not come on
(disconnected the positive cable from the battery. Hooked up the clasp to the cable and touched the positive battery. The light did not come on)/

[Geer_hed]

Ok, so there was something I forgot to ask. How do you know you're getting 11.5v? Are you reading the Voltmeter or are you confirming the reading with a Multimeter? The reason I ask, if you have a battery in another car that is at 12.67 volts, and you take it out and put it in another car without turning anything on (and you've already confirmed no draw), nothing should change between one reading installed in the first car and the next reading taken after the battery has been installed in another. Just wanted to be clear on that before we go and bark up the wrong tree. You can't put but so much faith in to those old Vmeters.

1) When the jeep is idling, what is the voltage at the battery? That should be your primary concern.

2) Again, try to disconnect the battery postive cable while the engine is running and see if it dies.

If you've got a new battery, you're getting good charge to the battery, and there's no draw on the battery, you might be wasting your time. That's all I'm getting at.

[TheDuke276]

OK,
I just started the Jeep and let in run for a few minutes. The voltage never got above 11.75 (it never hit 12).
Then I did as you asked, I pulled the positive cable wheile it was running ... and yes I stopped running.

So .....

remember, the battery is good, the alternator is new, the coil and the ignition module are new as well.

What shall I try next ... ?????

PS - thanks for the help with this geerhead. I've read a lot of your other posts as well and things are becoming clearer to me.

[Axiom]

hold the gas pedal all the way in while cranking it =]

[TheDuke276]

uhhhhhhhh, what?
are you kidding?

[Axiom]

yes im kidding... =] .

but i have the same problem with my cj... i went and bought a set of thicker battery cables.. a thicker cable from my positive post to my solenoid, and it cranked RIGHT up... also, it could be something as small as a shorted out wire somewhere... thats another thing i had wrong with my first battery... i had a set of fog lamps on my front bumper, hit a tree (cracking the lense) then went through some water and it shorted them out... i took the wires off and i lost drainage.

[Geer_hed]

Originally Posted by TheDuke276

OK,
I just started the Jeep and let in run for a few minutes. The voltage never got above 11.75 (it never hit 12).
Then I did as you asked, I pulled the positive cable wheile it was running ... and yes I stopped running.

This means either:

• Your Alternator is wired incorrectly, and therefore is not charging the system.
• Your Alternator is bad, and therefore is not charging the system.

Either way, you know it's not charging, so you're going to see a voltage drop because the engine is running soley off of your battery, and to make matters worse, the current expended is not getting replaced, so your battery is dieing a slow death. Atleast you don't have a draw, that would be insult to injury.

If you're fairly confident in the install of the alternator (it is pretty straightforward), then can we assume you wired it correctly? If your confident that the alternator wiring is ok, then I would recommend taking the alternator back off the engine and get it tested. Advance and Autoz will do that for you. I would also have them bench test the "new" one before you leave.

[TheDuke276]

starting to realize what Jeep stands for

j - just
e - empty
e - every
p - pocket

I'll be broke soon!

i will, though, investigate the battery cables, but i think they're OK

[TheDuke276]

Thanks geer hed

I'm pretty saure I connected the alternator correctly, but I will recheck the wire going to it.
anything I should be looking for???????

But this goes back to my main question at first.
the red resistance wire splices. one red goes to the coil. one red goes to the solenoid. when they're both connected and I throw the tester on them, they're dim. (KEY IS IN ON POSITION, OBVIOUSLY)
when I pull the one off the coil, the red wire at the solenoid lights up.
or is this normal?

and like last post said, could a battery wire be messed up??

Thanks geer hed

[Axiom]

Originally Posted by TheDuke276

and like last post said, could a battery wire be messed up??

doest have to be just a battery cable.

1) a battery cable on an old CJ could possibly be very thin, and if your negative is just a skinny, then your not pulling all the volts you should be, you need a thicker positive ( + / red ) cable for maximum output.

2) yes, it could be a shorted wire somewhere else, your lights, radio, cb, ANYTHING shorted can leave you with a slow battery leak

3) about the hold the gas pedal all the way in while your cranking it... if its a carbureted engine, you need to push gas into the enging for it to catch fire and turn over, so if it cranks slow still hold the gas pedal all the way in for about 10 seconds then SLOWLY back off of it and hold it about half way in... im not bull-=-=-=-=tin these are the things i have to go through every time i wheel, and i been wheeling with this jeep for about a year now.