Another good tip for dealing with stuck bleeder screws:
I am working on my 1960 Viking 2 ton, and I have found that if you use a pointed pic-tool (one that is hook-shaped at the end works great along with a straight one), you can scrape away all the rust and debri that has settled into the threads of the bleeder screw. By scraping all that minute particulate off the threads (and especially right up and around the threads going into the brake body), you can then soak it well with PB Blaster and the lube will penetrate much better. Also, when you go to loosen the bleeder screw, there will not be that encrusted crap to resist the turning action.
I like the idea someone mentioned about inserting a small drill bit piece into the bleeder to strengthen it as you apply pressure.
dwight
