Electrical/Battery/Alternator Issue

hoezaycuervo · 02-09-2008, 07:53 PM

Hey guys, first post and new Jeep owner. I bought a 78 CJ-5 w/ 304 in January hoping to not have to do a lot and slowly learn since its my first jeep and i'm getting into it now.

This week the volts slowly dropped during mid drive and eventually it wouldn't start. Took out the alternator and had it test, bad, so replaced it. Then I jumped the jeep off w/ my car and it ran fine, a little rough, but fine for about 10 min idling. Then I cut off and tried to restart, it struggled so i dumped clutch and it ran, but was misfiring and voltage was barely registering, so I assumed bad battery. Charged/tested/replaced battery expecting it to fire right up with new one and now when I turn the ignition, the lights come on but nothing happens, no click, no effort by the motor to turn over.....i'm lost as to what to do from here. Could the solenoid have been ruined?

**4.7stroker** · 02-09-2008, 08:18 PM

**CAUTION**
Remove the neg cable first and reinstall it last, this will prevent any possibility of a short
**CAUTION**
Remove both ends of both battery cables.
Using a wire brush clean the mating surfaces and the cable ends.
The surfaces must be bright and shiney.
Remove the wires from the starter relay clean connections and reinstall.
Remove wires from alternator clean connections and reinstall.
Reinstall battery cables.

All should be well providing there are no other problems.

Dwayne

CJhollic · 02-09-2008, 09:57 PM

if 4.7's advice doesnt work, try jumping it across the solenoid. If it works, chances are your solenoid is bad.

hoezaycuervo · 02-10-2008, 07:56 AM

Thanks for the input. I rewired the alternator with brand new wires, but will check the starter/battery and clean them up. How do I jump start with the solenoid? I have a 4 post.

hoezaycuervo · 02-10-2008, 10:24 AM

I double checked and cleaned my connections and everything should be good. When I laid a screwdriver across the top 2 post nothing happened (ignition was in "run" position).

Did I do that correctly? I have the positive terminal from battery, positive cable and 1 field cable from alternator on left side, starter cable on right, nothing on the I terminal, then a greenish blue cable on the S terminal. This is how it was wired when I bought it and it ran. The solenoid looks to be pretty new.

CJhollic · 02-10-2008, 11:03 AM

Quote:

Originally Posted by hoezaycuervo

I double checked and cleaned my connections and everything should be good. When I laid a screwdriver across the top 2 post nothing happened (ignition was in "run" position).

Did I do that correctly? I have the positive terminal from battery, positive cable and 1 field cable from alternator on left side, starter cable on right, nothing on the I terminal, then a greenish blue cable on the S terminal. This is how it was wired when I bought it and it ran. The solenoid looks to be pretty new.

With the jeep in park or neutral and the emergency brake on, turn the ignition to the midway position or "run".

With 2 screwdrivers or a pair of channel locks, short the two big posts. One comes from the battery, the other the starter.

This will turn the engine over and send voltage to the coil.

It sounds like you did it right. What happens when you do this?

If nothing, check the connection at the starter and the negative cable at the engine block.

At that point it narrows it down to a couple of things, bad starter or bad or uncharged battery.

hoezaycuervo · 02-10-2008, 02:27 PM

I finally fixed it....I think. My new neighbor came over and tested to find out my coil was stuck "open" so that the starter was always receiving power, which pretty much burned it up. I replaced the solenoid and starter and it fired right up. Thanks for the help guys!

Now...the new alternator is putting out 16V+ maxing out my gauge....should I install a resistor or regulator to tone it down or will it break in and be ok?

**Mike Romain** · 02-10-2008, 02:53 PM

Does the alternator have a warranty? Running a new alternator on a dead battery can kill it and void some warranties. A friend got a big green alternator or some such thing and I read that in the warranty sheet.

16 is far too high. I think I would check it with a multimeter on the back of the alternator to be sure.

hoezaycuervo · 02-10-2008, 07:49 PM

Quote:

Originally Posted by Mike Romain

Does the alternator have a warranty? Running a new alternator on a dead battery can kill it and void some warranties. A friend got a big green alternator or some such thing and I read that in the warranty sheet.

16 is far too high. I think I would check it with a multimeter on the back of the alternator to be sure.

I actually replaced the battery as well through this process, so my electrical system is essentially brand new other than wiring. The only drain the new battery saw was trying to crank with the bad solenoid and starter.

**Mike Romain** · 02-11-2008, 09:33 AM

Quote:

Originally Posted by hoezaycuervo

I actually replaced the battery as well through this process, so my electrical system is essentially brand new other than wiring. The only drain the new battery saw was trying to crank with the bad solenoid and starter.

Well.... I was meaning this statement:

Took out the alternator and had it test, bad, so replaced it. Then I jumped the jeep off w/ my car and it ran fine.

And then: but was misfiring and voltage was barely registering.

For your second start which implies to me the alternator might have gotten smoked when you first put it in on the dead battery.

It happens. I would be testing the alternator before progressing to other things.