Alternator Question

For those of you who have read my recent other post about carb issues and now electrical issues (http://www.earlycj5.com/forums/showthread.php?93446-All-back-together-now-I-m-ready), I am breaking out this topic and question. As part of my refurbishment, I have cleaned up my engine compartment. I've pretty much replaced every electrical part except for the alternator. I know the replacement parts have worked because I have started the jeep many times a few days ago as part of the carb adjustments. Now, only clicks, and sometimes nothing at all when you turn the key. I started pinpointing by swapping the working (but nasty) parts i took off. Same thing no matter new or old parts. I sense a bad alternator. My question is, will a vehicle do nothing when you turn the key with a bad alternator even when a battery is fully charged? Thanks.

 

Nope. You have problem with the battery, or the cables, or the solenoid, or the wiring to the solenoid, or the ignition switch.

This is an intermediate Jeep? Have you tried jumping the solenoid with your jumper cable?

 

73 with a 304. It must be the wiring itself then. I've tried 2 different batteries, 2 different solenoids, 2 different ignition switches, 2 different voltage regulators. The only physical wiring differences I've done include kc lights (which I've disconnected), engine to frame and body to frame grounds, and a tach install (which I connected the feed to an ammeter terminal and have checked for tightness of the connection). I've checked all wire and cable connections. Lights and radio will occasionally work. There is fire across the solenoid when shorting.

 

The solenoid has to be grounded. The ground is through the base. If the base is corroded, it may not work even if the wiring is right.

 

So, if it's setting on a freshly painted fender, I should sand away the paint under it where the metal can contact the fender? Or should the screws securing it suffice touching the fender in the holes? Either way, I haven't checked this.

 

Fresh paint... bad for grounds.......make sure metal to metal contact is being made with the base and the fender.

 

I ran a dedicated ground wire to my solenoid mounting screw for peace of mind.

 

I just went out and sanded around the mounting holes on the fender to get metal to metal contact and no luck. I mentioned my lights not working too. The solenoid wouldn't affect lights too, would it?

 

I see on this wiring diagram that the ignition switch is grounding when the switch is turned to start. http://oljeep.com/gw/74_tsm/22-7-CJWiringDiagram.pdf
Is this wire tied to the dash panel? I need to trace this out to see if its good. I remember seeing the ground terminal on the switch, which does have a wire connected to it. This to me still doesnt explain lights and radio not working. Also i mentioned the tach "floating" under zero sometimes when i turn the key and nothing else happens. Ive sanded battery terminals and posts. Ive got the type of battery terminals that clamp to the cables. They are tight, but do these types pose more problems than a complete off the shelf cable?

 

The terminals i have clamp to the cables using a silver metal, so the copper cables are not directly connected to the lead ends. Could this be a spot where current is not flowing?

 

I never trust the clamp on battery terminals. Moisture and air get wicked through the cable strands and can cause corrosion inside under the casing.
The first thing I do is replace battery cables with some new, factory sealed ones of the proper length. They are cheap,easily changed, and can be found at just about any auto parts store.


The grounding on these jeeps is totally dependent on the metal to metal contact between the body panels. The surface rust and dirt that is trapped between the frame and grille, the grille and fender, the fender and tub, the tub and dash panel are all acting like insulators in your ground circuit. I hard wired dedicated ground points on each body panel that all lights ground to and then run all the points to a buss by the battery.

 

I picked up some new battery cables so i can try after work. I guessed at the lengths: 25" for positive and 38" for negative.

 

Hey Drednot, what exactly do you have connected into your starter solenoid in that picture. Do you have any cable that goes from the volt regulator for the alt plugged into the Starter Solenoid?

 

New cables solved my electrical problem, now back to the carb. Thanks for helping weed out my problems and helping me understand what does what.

 

The starter cable, coil and duraspark module, start, battery cable, 12V main to harness, alt output(fusible link), alt exite, and the ground wire to the mount

Keep in mind that mine is running the later model Delco alternator and duraspark electronic ignition.