Alternator, Battery, or wiring issue?

[SGT]

Alright, I have a 79 CJ7 that has a generation II chevy 350 in it. I did not do any of the conversion on the jeep myself, it was like this when I bought it.

I bought the jeep last summer and drove it all summer with no electrical issues. This winter I was pulling a tree with my winch and the winch stopped working but the jeep was still running so I figured the winch was shot. Once the jeep was parked for a while I decided to try to get the winch to respool. I started the jeep up and it respooled but got slow. So I left it and came back to it a couple weeks later and the jeep battery was dead. I jumped the jeep and ran it for about 30 minutes. I shut it off and tried to start it up right away and the battery was dead. So I put a charger on the battery for over night. I started the jeep up and put a VOM on the alternator. It was reading 11.5v at the alternator and dropping. So I put a brand new alternator in it that I had sitting around and put a new yellow top in it. The alternator is now reading 12.5 volts and dropping slowly. I took the alternator off and took it to a local generator shop and had them test it and look it over. They said it is charging good and everything inside is good. So I put it back on and it still is not charging.

What do you guys think? Short somewhere? I'm stumped otherwise.

Sorry for the long story.

Thanks

 

[caveman]

Not sure if it will be the same, But I had a bad connection on my amp meter and it acted about the same as yours.

 

[Lumpy Grits]

How old is the battery?
Your alt is charg'n the DEAD battery. That's why the low volt reading. Alt chg'n a dead battery is NOT good on the alt.
Chg the battery and then check the alt for volts.
You want no less than 12.5-13.0 vdc at fast idle (1K rpm)
My bet the battery is gone.
Take the alt in and have it tested for AMPS. That's where the alt 'punch'.
Volts are just the 'carrier'. Amps are the 'horsepower'.
LG

 

[SGT]

The battery is a brand new optima yellow top that I put in at the same time at the alternator. They did test the alternator at the generator shop but not sure if was for amps or volts. I would assume both.

 

[Torxhead]

I would suggest disconnecting that winch at the battery and go from there, As your overloading it yanking on that tree could have caused some issues. It does sound like you might have a drain somewhere. Having a battery loose its charge completely can ruin it.

 

[SGT]

I never reconnected it when I put the new battery on.

 

[Lumpy Grits]

NEVER ASSume.
Ask'em, and you want to know the readings.
I would recharge the battery over night on a slow chg. Disconnect the battery to do this.
You could have an issue within the alt, that's draining the battery too.
What gauge cables are you run'n for the winch?
Have the main GND(-)wire come'n from your battery attached to the top post of your starter.
FWIW: All of my starter and winch leads are 1/0 arc-welding cable.
I only use pure copper connectors also.
Sure hope you using the top posts of the battery, and NOT the front side posts.
LG

 

[SGT]

The battery isn't dead yet but it's not getting better. I put new 4 ga on it... I dont know if that would be undersized but they don't feel warm. I am using the to posts.

 

[Lumpy Grits]

4 gauge is to small IMHO. Who made your winch?? It stop'd work'n because of a thermal switch was tripped inside of it. Also when run'n the winch, you want your engine RPM up around 1100-1200 rpm to get the most out of the alt.
Get the battery charged up.
Take jeep for a 10-15 mile drive.
Park it for 24-36 hrs. IF it doesn't restart-You most likely has an internal drain via your alternator.
CHG the battery all the way up again and repeat the drive.
Park it and disconnect the POS(+)side of the battery.
After 24-36 hrs. Reconnect the battery. Will it start??
BTW: What's the AMP rating for your alt? Stock is only 45 amps and that ain't much.
LG

 

[SGT]

Which is a warn 9000. Alternator it's a "custom" Stinger brand - 200 amp, 14 volt. The battery is not draining unless I'm running the jeep for a while which I really haven't ran it too long since I don't want to get stranded or have to call Three As. I'll try your trouble shooting when I get a chance.

 

[Lumpy Grits]

My bet is the alternator is drain'n your battery when the engine is off.
You really need to have it ck'd for it's real amperage output. Lots of those magic 200 amp alternators- ain't.
BTW: I run a 65 amp alternator on my Jeep, and have never had an issue with my Warn 8274.
I'm run'n a Optima red-top.
Please post up your findings-
LG

 

[SGT]

Will do... Thanks for the help.

 

[Torxhead]

Hopefully you have the larger alternator that came with the GM motor and not the oem CJ unit. On the CJ wiring, where the alternator charge line goes to the battery from the starter relay, there is a fusible link that can go bad and could cause charging issues. Another check you can make would be to run a jumper wire from the alternator to the battery negative and see if that helps.

 

[Hedgehog]

Let see:
- New battery
- New Alternator that has been checked by an alt. shop
- Warn 9000 Winch, un hooked
- Battery drains WHILE you are running
- You've charged the battery

That leaves only one possibility, the battery is discharging more than the alternator is providing. But everything is checking out as OK. About the only thing left is, and please don't be insulted here, is your alt. turning while the engine is running? Check your belts. Stranger things have happened. If you can't figure this out, I'd take the whole jeep to the alternator shop and have them test the whole system. You've obviously got a drain while the vehicle is running that isn't being compensated for.

The next thing to do is pull that Chevy paper weight out and put in a real AMC engine, then all your problems will be solved, the sun will shine and admirers will follow a a respectful distance ........... let it be known that I'm just having fun with the whole Jeep VS Chevy thing. There's nothing wrong with a Chevy 350.

 

[SGT]

Belt is new and tight.

 

[Hedgehog]

Is your engine grounded really well?

 

[Cduke88]

See if there is a arc when you connect the battery terminals. If you see a arc then you know something is draining your batt

 

[Jimbos76cj]

Ive got 2 cents... Have you checked your excite wire for power. Im not sure if its been asked or not but you have the standard chevy alt with the 2 prong plug on it? if there is not 12volts going to that wire when the ignition is on the alternator will not turn its self on. also make sure you have a good ground from your alt to your motor. I had a rusty alt bracket blasted and powder coated and when I put it all back together it wouldnt charge. Luckily I bumped a wrench onto the alt body and motor which threw a spark and heard the alt kick on.

 

[Lumpy Grits]

Belt is new and tight.

Any updates?
LG

 

[SGT]

Alright,

I finally had time to get out and work on this thing. I narrowed it down to the voltage regulator.

Basically, me not knowing much about how the alternator works, I didn't realize that the "high output" alternator that I put in it does not have an internal regulator. So instead of messing around with an external regulator I just decided to buy a remanufactured alternator. I put the reman is and shes charging. I think that the old alternator voltage regulator is bad and that is what prompted this whole ordeal to begin with.

At the end of the day I have a slight better understanding of how the alternator works and the Jeep is running.

Now its time for the rest of the items on my list ...

Thanks for the insight guys!