Issues with my '74 J20

[ehr400]

Hello, new guy here. I have a '74 J20 360, 4 speed. The issue I have is the other day I was driving around and the lights got real dim. The volt meter was fine though, any ways I pull in the driveway and shut it off and it wont start just click. I replaced the starting solenoid, charged the battery and still click from the starter. Could my starter have a dead short in it causing it draw current? Altenator checks out fine too. Kinda stumped.

[biotex]

Welcome to the madness!
Jeeps are notorious for bad grounds. I would clean every ground first thing. Might even add some extras. Also take the battery in and have it tested.If that doesn't fix, report back.

[ehr400]

Thanks you, I will do that and see what happens.

[Elliott]

If ya try juming it with another vehicle (fast rpm) after letting the jump charge it a lil (and your battery terminals are clean/tight) then you know it's a weak battery.

[ehr400]

Ok will I think i have a new set of issues. First off I put the freshly charged battery that checked out good back in and cleaned/ tightened grounds and connections. Insert key in ignition and turns over slow. Turn ignition to the off position and keeps cranking. then it fires up. Running good and everything, however if I did used anything electrical the volt meter would drop alot. When i turned on the headlights it killed the motor. So I try to start it again. Put key back in and turn it over, turns over real slow, then I turn the key to the off position and it keeps cranking, remove key still cranking. Meanwhile it melted my jump box negative handle.

1. The question I have is, is it possible to have a bad ignition switch?

2. Bad ground still?

3. Voltage regulator/ bad altenator?

At a loss here and this thing has like no electrical anything on it. Any help would be appreciated! Thanks!

[biotex]

The ignition switch mounts on the top side of the steering column under the dash. It is best to unbolt the 2 bolts holding the column up, so you can access it better. There is a rod that slides forword when you turn the key, and that rod attaches to the ign. sw. Two bolts mount the ign. sw. to the column, and those bolts are how you adjust the switch by sliding it forward or rear. If those bolts came loose, you would have a problem, but I would just replace the ignition switch and be done with it.

Once that is adjusted, or verified good to go, then I would look at the starter solonoid that is mounted on the fender. They are cheap, so I would just replace it also.

You probably have a bad starter causing the battery drain, and slow cranking. Take it off and have it tested. Starters can short out internally, and cause those exact issues.

[ehr400]

I was kinda thinking that about the starter also. I will pop it off tonight or tomorrow and see if that is the issue.

Would a bad ignition switch cause it not to charge also? I will check the ignition switch also, seems easy to get to.

Thanks!

[tgreese]

Sounds like you have two separate issues. First is the starting - that the engine keeps cranking when you turn the switch off means something is wired wrong. There is a "S" and an "I" terminal on the top of most replacement starter solenoids. The I terminal is only used on some applications to deliver power to the ignition when starting. The "S" terminal activates the solenoid. With the key off, you should be able to crank the engine by jumping from the battery terminal on the solenoid to the small "S" terminal.

If you disconnect the "S" and "I" terminals from any wires and turn the key on, you should have power to the "+" terminal on the coil. Now jumper the "S" terminal to the battery terminal on the solenoid, and the engine should start.

The "S" terminal should only be hot when the ignition switch is turned to the "start" position. The "+" terminal should be hot in both the "run" and "start" positions, and not when at "off" or "accessory".

I would also disconnect the alternator (tape the wires) to test this. It's possible there's something wrong in the alternator/regulator that is backfeeding to the ignition, but I don't see how it could keep cranking by backfeeding through the charging circuit. More likely you had the "S" terminal connected to the ignition somehow, either in the wiring or through your start box.

hth!

[biotex]

I agree two seperate problems. That is why I say replace the ignition Sw, and or the solonoid, and then the starter. Those are the only components in the loop that I can see causing issues mentioned.

If the ign. sw. is not the culprit, then the solonoid contacts could be sticking closed causing the starter to spin with the key off.
The way I look at it, these are parts that should be changed anyway if they are 35 years old.

[rocklaurence]

I had the same issue on the J10 when I got it. I had a low battery and with the low voltage the starter draws more amps (P=IxE). The high amps welded the solenoid contacts together preventing the starter from stopping. In my case, the + lead to the battery started melting. Replace the battery and the started solenoid as a unit.