Battery goes dead while truck is parked

[jgb680]

I just traded a jeep for a Chevy K30 CUCV. I put new batteries in the truck today. It started great and ran great, but when I was driving it the light on the dash for the second battery was flashing. I parked the truck for about two hours then tried to start it, and it doesn't have enough juice to start. Any Ideas?

 

[televisionman007]

battery might be going bad, Check the connections and have autozone test the batts

 

[jgb680]

The batteries are brand new, I work for autozone...

 

[jatonka]

sounds like you have access to a tester, check the output of both alternators.

 

[jgb680]

i'm not real familiar with the 24v system... is there more than one alternator? i only saw one on top of the motor.

 

[papabear]

Also check your battery terminals and grounds??

 

[bubba_got_you]

[FONT=&quot]As far as 6.2 electrical problems I only can really help on 12v but there should be 2 alternators. One on each side.unless it is no longer 24v
[/FONT]

 

[jgb680]

i just got the truck today, i will look into it more in the daylight. It is for sure 24v though

 

[Blood_of_Tyrants]

The CUCV uses 24v (two batteries, each with its own 12v alternator) for the starting circuit. Check the voltage on both. If just one is low, put jumper cables across that battery and you may be able to crank it. Then check voltage on both batteries. Chances are that you either have poor connections or a bad alternator. The alternators on the CUCV are not like standard GM alternators so you will have to get one made for the CUCV or have yours rebuilt.

Otherwise the rest of the electrical system is just like the stock GM vehicles.

P.S. It is fairly easy to convert the CUCV to a straight 12v vehicle with a bit of rewiring and a starter change.

 

[jgb680]

In simple terms, what all does it take? I'm wondering if that might be the simpler and cheaper way to go....

 

[Warthog]

Post a picture of your alternator(s).

A stock CUCV has two 12v alternators and two 12v batteries. Some trucks have been converted to 12v systems.

The drivers side alternator (GEN1) charges the front battery. The passenger side alternator (GEN2) charges the rear battery.

You can test the alternators just like a civilian unit. Except that instead of using the case as a ground, you use the Isolated Ground Stud.

All of this has been covered many, many times.

Without more info on you truck, we are just guessing. We need to know how many alternators, how many batteries, how are the batteries hooked up, etc.

****************

Why is it whenever someone has an issue with CUCV electrical system, they want to gut the wiring and start over? Is rewiring the truck easier to do that trying understand the 24v system?

The 24v system is not THAT COMPLICATED. Different yes, but once you spend some time studying the wiring diagrams and working with the system, it is very simple.

 

[Warthog]

...., I work for autozone...

The truck doesn't exist. It isn't in the computer.

Just messing with you. As you know your computers will not give you any usefull information.

Download all the Tech manuals and Parts manuals. Every GM part number is listed for this truck. You should be able to crossreference the numbers.

Haynes and Chilton manuals don't help either.

The Military spent millions of dollars writing Tech Manuals for these vehicles. They are much better than the Haynes.

 

[KsM715]

The Military spent millions of dollars writing Tach Manuals for these vehicles. They are mush better than the Haynes.

The one thing our Gov. has done right.

 

[jgb680]

What does it take to convert the truck to 12v? I'll try to get some pics up tomorrow. It is 24v it has the positive and negative post wired together... Where's the best place to get a manual on it? like i said all this is new to me...

 

[Blood_of_Tyrants]

What does it take to convert the truck to 12v? I'll try to get some pics up tomorrow. It is 24v it has the positive and negative post wired together... Where's the best place to get a manual on it? like i said all this is new to me...

Right here on this site. Start here to download the CUCV manuals.

Steel Soldiers :: Military Vehicles Supersite

Then search for 12v conversion. There are several threads. I wouldn't convert unless the starter is bad. Like I said, it is simple. Replace the starter, remove one battery, the left alternator, bypass the blow plug resistor bank, and a a few rewiring mods and you are done. But 12v starters are fairly expensive while 24v starters are not. Sort of odd.

 

[jgb680]

Thanks for the help guys! I think I can probably figure out my problem now

 

[Armada]

Keep the starting and glow plug system stock if you can. Makes it alot harder to troubleshoot when you start changing things since the manual will no longer apply to those systems. Those systems work better than the civy 12v trucks, especially starting in cold climates. Spend some time with your new truck making sure everything is operating, cycling, and working like it should. Good luck!