Generator dead or just a loose wire?

[elijah]

Hey guys,

I've been fixing up my first jeep, so these questions may be a bit elementary. Sorry if it's been addressed before. I did search out answers prior to posting.

I own a '66 CJ5 , 4 cyl. flathead. While exploring an abandoned golf course I turned it off for a hike w/ my lady and when I came back I got nothing. No ignition click, whirring, strain...nothing. I think it must be a blown fuse. I swap one that I find blown out and still nothing. (I believe it went to the heater.) Next I think dead generator or loose wires. I find a loose wire at the ignition behind the dash that broke off and crudely attach it back. I'm glad the truck wasn't in gear because without a key in it tries to start and nearly does. It starts like a champ and I drive the jeep home on my other car's battery. Later I think it must have just been that loose wire and perhaps my battery is fine. Not so, the new battery I put in the jeep is totally drained.

So, here's my question, could that loose wire at the ignition have killed all power to/from the generator meaning that if I jump start it with my dead battery (which is brand new) and run it for a while it would recharge?

Also, and this question may be dumb, but can I do a simple swap from a generator to an alternator or larger generator that I salvage? Would there be a noticeable benefit?

Thanks ahead of time!

 

[Saddle Tramp]

Not an expert here but a generator puts out direct current while an alternator puts out alternating current. As such if your jeep is set up for DC (generator) then I think if you swap to AC (alternator) the power will need to be converted back to DC to before it can be used with your jeep’s electronics to avoid damage.

Most electrical issues have something to do with bad grounding so I always check that first but I would make sure the generator is putting out power. The other issue could be that the voltage regulator has gone south.

 

[thiswontbetooexpensive]

It's all DC unless you run an inverter to AC. All vehicles, worldwide.


This won't be too expensive Dear! That's what I keep saying. Over and over again.

 

[CJ]

Yep, an alternator has a built in rectifier so it outputs DC.

 

[elijah]

Thanks for the info!

I let the jeep run after a jump for ~15 minutes on my dead battery today. When I tried to start it gave a terribly lame effort. I guess my generator isn't working so hot huh?

So as long as I match the voltage of my jeep's setup I can use any alternator or generator to power my battery? Does anyone have one you would suggest that would be robust and cheap that I might possibly find in a junkyard?

 

[Saddle Tramp]

 

[thiswontbetooexpensive]

Thanks for the info!

I let the jeep run after a jump for ~15 minutes on my dead battery today. When I tried to start it gave a terribly lame effort. I guess my generator isn't working so hot huh?

So as long as I match the voltage of my jeep's setup I can use any alternator or generator to power my battery? Does anyone have one you would suggest that would be robust and cheap that I might possibly find in a junkyard?

When you get it started, take the positive post off of the battery. If it dies, then you have a bad alternator.

If it keeps running, then it's one of two things:
1. The battery is bad. Take it for testing and charge/replace as necessary.
2. You have a drain on the system somewhere. (Think dead short draining the battery)

The fact that it will run after a jump start leads me to believe that the problem is a short that can be determined by diagnosing the fuse block with the key off. Disconnect both posts and tie them together well with metal wire of some sort and check resistance on switches and connections with an ohm meter of some sort.

This is a warning. This is very time consuming and will not be fun. You can take it somewhere to do this for you, but take your checkbook/credit card with you. I work pretty cheap when it comes to stuff like this for myself. If you get a quote for this wire short tracing; I would be willing to bet the price you get will be an hourly charge that will leave you wishing you went to trade school to be a mechanic.

 

[elijah]

Oh man,

the battery is brand new. this sounds like it's going to be...fun. I recently replaced a small 9v fuse under the dash that I think went to my heater also my tail lights never worked, so I guess I've got some likely culprits to check out?

If I'm understanding correctly, it's probably a wire that's grounded that shouldn't be somewhere? Could I disconnect each electrical system (brakelights, headlights etc.) , start the jeep, do some chores and see if it charged enough to restart after 15 mins of running? If I find one that when disconnected lets the batts charge then I've found the beginning of my short problem?

Anyone got a wiring diagram for a 66 CJ5 sitting on their harddrive?

i already wish i went to trade school.


rads,
-elijah

 

[Tinman22]

There is a school for trading?!?! I would have been good at that.