A worn pilot bearing can give viberation as the engine picks up rpm.. I have seen em run without pilots in them. I doubt that would be your problem. Your problem does sound like a hyd pressure problem. By pumping the pedal perhaps you can build up enough pressure to open the clutch and allow shifting to occur. If so then replace the master cyl.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

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