hi all.lost all pressure on clutch and was getting bubbles in master cylinder.it was suggested that it was more than likely the slave seals so i replaced them.with the master cleaned and empty i tried to back bleed from nipple with syringe.i could only push so much in then it would start seeping out off nipple threads[pushing hard].no fluid in master.i tried then the filling master and pumping,releasing nipple and so on[no pressure]then i tried sucking out through nipple.was just getting air and fluid[none from master] when i pump master now im not getting bubbles.im confused. yamaha fj1200