The only fully assembled lock assembly that I have a key for displays odd behavior in terms of the key position vs column lock pin position. I took a series of four photos showing what happens with the key in different positions:

1. (Top image) With the key in Positions I, II, or III, the lock pin is fully retracted, freeing up the steering. Looks good so far.

2. With the key turned all the way OFF, but still inserted in the switch, the lock pin extends about 1/8" - probably enough to penetrate the column tube but not enough to engage the slot in the steering shaft.

3. With the key pulled out of the switch, the locking pin extends a bit further to about 1/4"- "possibly' enough to engage the slot in the steering shaft.

4. (Bottom photo) Here's the weird part - if the key is re-inserted THEN the locking pin extends to where it SURELY engages the slot in the shaft. I can then remove the key and the pin stays fully extended.

I have another partial lock and switch assembly that doesn't act this way, but it's not a complete assembly. On that one, the locking pin fully extends the first time you remove the key - that seems more correct to me.




Also, in the next photo, I am showing two different locks, the difference being the way they attach to the column. The "slide-on" type is P/N 682656. The "strap-on" type is P/N 1212291. Does anyone know which one is proper for my 1973? They both appear to have the same overall dimensions, same switching, etc. I would more than gladly use the strap on type but I don't have a key to fit.




So how do you tear one of these apart? It appears you can separate the two halves of the lock assembly by drilling out the pin. But to replace the tumbler part it appears I would need to pry out the square plate at the end. Anyone ever done this?