Datsun sure didn't feel the need to go into much detail into these mechanisms, now did they?  I think I may have figured out my problem, but am asking for input from our community experts before I start putting force on things that shouldn't be forced.

I believe my adjuster mechanism is rusted together where it should pivot.  So.  should the adjuster fork pivot on the arm which is attached to the parking cable?  On mine, the end of the fork which contains the adjusting wheel does not move freely on the shaft.  That being the case, the lever arm which spins the adjuster wheel isn't able to return to it's starting position.  Conversely, I can't see that the parking brake will work since the lever won't move with the adjuster fork holding it in place.

Secondly, any helpful tips in freeing these up other than penetrating oil and patience?

    

 

Thanks for the helpful input, guys.

Yes, the arm with the gear on it is supposed to pivot freely on the parking brake linkage, and yes, they rust up and stop working.

This pic was taken to highlight the parking brake seals (it wasn't taken with the intention of showing the pivot function), but you can see how the arm with the gear on it is at a weird angle with respect to the rest of the assy:

As to how to get it free? The usual... Oil, patience, persuasion, heat, etc. I don't have any silver bullets.

Soaking in Penetrating oil, CLR, or Vinegar will all loosen the rust.  It does require some force to pivot though. You could put one end in a vise and wiggle it to help it along.

You could buy some of the Eastwood rust removal solutions and soak it in that and it will come out as clean metal...

Overkill but it has what you want:

 

http://www.classiczcars.com/topic/39668-77-280z-drum-brake-refresh/

 

Great info as always, gents.  Thanks.

The photo documentation is particularly helpful, Blue.