[mikethedruid]

Bob, you mean you haven't rebuilt all the bakelite condenser blocks? That should be done to ALL of them to prevent any of these kind of problems. Just because the old paper condenser is in a tar filled bakelite block does not guarantee its immortality. This may or may not solve your immediate problem, but at least it lets you rule out a lot of possible problems. It also acts to prevent future problems as these ancient parts inevitably fail. The only exception I make is the hermetically sealed cans found in Scott receivers which show no signs of leakage. They are pretty much immortal as long as they remain sealed.