Coil fuse keeps blowing!?!?!

Ok, so some background.

1974 CJ5 258 re-wired with an ezwiring 21 circuit harness.

Jeep stored over winter and the battery went down, tried starting it and the battery was shot = lots of cranking with no firing.

Charged battery and Jeep ran fine.

Fast forward a few weeks and now the Jeep will randomly blow the coil fuse on start-up. It will run in CRANK, but once it transitions to RUN, the fuse blows. I had this happen one other time while trying to start it with a battery charger hooked up.

The first time it happened this go around I was at an auto parts store and started it with my headlights on randomly. That blew the fuse. Figured it out, bought new fuses and put one in, fired up just fine. Then I shut it off to try again and it blew one more time. Add 1 more new fuse and I got home.

I tried starting it in my garage a few times and it did fine, then I went to start it for a ride and it blew yet again. I have been out of town and now am back to try to dig into it a bit...

Any ideas on what can keep causing the coil fuse to blow? Bad ignition switch, starter hanging on??

Replaced the coil with no change.

Any help is appreciated before I start throwing parts at it....

 

points or electronic? if points resistor in the power wire?

 

A '74 has points, so I's assume it still is points.

A replacement wiring harness makes things more difficult.

First thing I would do is inspect the wiring from the battery to the coil. I'd look for places where you can have an intermittent short to the body, or other wires. Theat it fails when you drive around suggests that somethng is shorting out due to movement.

 

Do you really have to fuse the ignition to the coil? The earlies are not. The coil produces a reverse (kick back) voltage and it can be quite high. It will sometimes blow your test light and the starter solenoid coil will do the same thing. Not saying you don't have an intermittent short but just wondering....

 

So the primary lead wire going into the distributor had..uh....let's just say a less than favorable electrical connection. Red-did that and it fired right up. Gotta check it a little later and see if it holds....

I have had it not work and work off and on so I don't know yet if that was all that was wrong. Fingers crossed..

 

The factory coil needs to have the proper length of resister wire. Double check the condition of the resister wire. Does your new wiring have the proper resister wire? You can by a coil that does not need the resister wire.