84 CJ7 starter engages in the on position

I've been helping a friend get his 84 CJ7 put back together. Tried starting it today and the starter engages with the key in the "on" position and won't quit until you turn it to "off". Thought it was a bad ignition switch so we replaced it and same issue. I took the column apart and everything seems to be in order there - key switch seems to be working fine and springs back from the start position. linkage rod is straight and not binding and no slop in it. It started and ran fine before (last year). We have not messed with the wiring other than to replace the starter solenoid (probably didn't need to - turned out to be bad connections at the battery) and to re - install the alternator that was taken off to replace the bracket after the non working AC was removed). It's a 6 cyl with a manual transmission. It's a real head scratcher. Thought maybe the solenoid might be wired wrong. Left side big terminal to battery and right side big terminal to starter. blue /green wire from ignition the left post on top and the right post is empty. Un taped the wiring harness and don't see any evidence of shorting anywhere. Does anyone have any ideas where to start looking or what we need to do to trouble shoot??
Thanks

 

Sounds likely you have the solenoid wired to the "run" output instead of the momentary "start" wire, from the switch.

 

The switch still has the factory plugs so the wires couldn't have gotten crossed there and there is only one start wire with a boot on it to go to the solenoid S terminal - no other wires anywhere close. I was thinking it has to be in the wiring somewhere but was not able to find anywhere that the run and start wires could be shorting together. A couple hours of internet searching last night made me wonder if I'm getting a back feed through the ignition module - apparently the start wire runs through the ignition module.

 

Can you test to be sure the new switch is the correct one? i.e. could the switch output be wrong for your existing wiring plug?

 

I probably can since I finally found a picture of the switch with the terminals labeled. However, the old switch (which was working last year) was doing the same thing that's why we bought a new one.

 

Is the rod engaged in the proper hole on the switch?
Did you try adjusting the switch?
Does ACC work properly?

 

Turns out it was a bad ignition box/module on the inner fender. The acc wire was back feeding inside the box to the start wire. Replaced the box and everything is working. I found a reference to that ignition box on another forum that said the start wire ran through the box and the problem could be in the box and after exhausting all other ideas decided to give it a try and it worked. Thanks
JRS