73 K20 wont shut off

[73BigBird]

My 73 K20 with a 350 wont shut off with the key all the sudden. Had the truck about 6 weeks and had not had the issue previously. I just added a second battery, they are wired in parallel with no isolator. I also changed out a fuel sending unit that was not working, not that I think this has anything to do with it but want to give as much info as possible on what has recently been done prior to it starting this.

Truck starts fine, seems to be running fine. When the key is turned off the engine keeps right on and doesn't miss a beat. I can take the key out. When they key is off with engine running the blinkers are off and not getting power, as soon as I turn the key back on the blinkers have power and work. I unhooked the second battery and made sure everything was hooked back up to a single as it was before it started doing this, no change. I replaced the ignition switch today and still doing it.

I cant help but wonder if the recent battery work did something, seems like to big of a coincidence for this to have magically started this right after I was replacing stuff.

Any ideas on what to check next or other threads that deal with this would be greatly appreciated.

 

[bucket]

I'm leaning towards a badly worn, or slightly misadjusted ignition switch. Not the key lock cylinder, but the ignition switch itself.

Can you turn the key back to the Accessory position, or is the cylinder too worn out for that?

 

[73BigBird]

The ignition switch is new, although I may have not had it adjusted right. I had it positioned as the install directions said, which was the same as the old one was whe3n it came out.

The key will go back to the off position where I can get the key out, but will not go back any further. It has been like this since I got the truck.

I think I am going to take a look at the lock cylinder tomorrow. The thing that still confuses me so much is that prior to the latest work it never had this issue. Now every time I start it, it wont turn off.

 

[bucket]

I think you just need to adjust the ignition switch, as long as the key is turning back to Off.

The lack of the ACC is a separate issue. If the cylinder is worn, it commonly can't rotate that direction. Also, the earlier columns have spring clip to retain the lock cylinder. The column housing is very thin and fragile in that area, so if it's broken, you can't actually push in the cylinder so you can turn it back because the whole thing moves around in the housing. The later years (I don't recall when) have a retaining screw for the lock cylinder that does a better job of holding the cylinder in place.

 

[73BigBird]

I'll try adjusting the switch a bit and see if that helps, thanks for the reply!

 

[73Henderson]

Did you get it? My 73 chevy with tilt is doing the same thing, hoping for some pointers on the problem or solutions. Thanks