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Discussion Starter · #1 ·
For the first time in twenty years and over 170,000 miles, my 1986 cj-7 broke down and had to be towed back to the house (no complaints here, it was and still is a great vehicle).

Anyway, the first symptoms showed up a couple of weeks ago by it not starting the first try, but consistently starting on the third. Now it will start but cuts off as son as I let go of the key. I’m guessing an ignition problem (worn out) or starter solenoid. Any advice no matter how basic is appreciated and thanks in advance.
 

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More than likely ignition module or ignition switch.

Your Jeep used the DuraSpark ignition module.
That module has a seprate circuit for cranking and will start when cranking, but when the key switch moves back to the 'Run' position, the ignition module uses a differnt circuit.
This 'Run' circuit may be 'bad'.

Also, there may be a problem with the ignition switch it's self.

I'd have the ignition module tested first (easiest).

If a new ignition module doesn't do it for you, let me know and I'll give you the test proceedure for the rest of the 'Possibles'...
 
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Discussion Starter · #3 ·
First off, thanks for the advice, I replaced the ignition module as suggested but no joy (only a 22.00 part). I also checked the ignition switch w/ a multimeter and I'm pretty sure it's OK since I can find 12 volts with the key "on" at the coil.

What's interesting (and scary) is if I leave the key "on" for any length of time the ignition wire (red wire) gets so hot it glows and starts to burn. This leads me to believe the problem may be the solenoid since when disconnected, the ignition wire no longer glows red. And there's continuity between both posts on the solenoid which I believe is wrong with the key on.

Thanks again for the help, I'm learning a lot here.

...Mike
 

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[ QUOTE ]
Now it will start but cuts off as son as I let go of the key.

[/ QUOTE ]

I had that one time and it ended up being my Ballast resistor. But I do not think that is an OE part, but rather something the PO installed. It would only stay running with the key in the start position. Unfortunately that's not too good on the starter /ubbthreads/images/graemlins/grin.gif
 

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When you unhook the starter solenoid you unhook everything in the jeep.
The main jeep power wire hooks up at the starter solenoid.

You coil is ground out, either internally or externally.
(Probably internally.)

The other possability is your resistor wire gave up and cooked it's self.
(More likely the coil gave up and took the resistor wire with it!)

Do you have an aftermarket tachometer?
If you do, there could be a third option.

If the coil is grounding out internally (probably the case), the 'Hot' wire going into the coil will get very hot.
The Green ground wire will not be very hot.

The resistor wire going in the coil will get very WARM when you leave the ignition on, but don't start the vehicle.
The coil should get a little warm too, but nothing that will keep you from putting your hand on it.

If you can't keep your hand on the Red wire going to the ignition coil, the coil is grounded out internally.
What usually causes this is a bad ground wire to the head(s).

High voltage can't find a ground at the spark plug, so it grounds inside the coil, ruining the coil windings in the process.

The spark plug wires, coil wire and a bad head ground can all be the 'Problem', or the resistance of all three can add up to the problem.
 
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