| You might find that you need to bleed the master cylinder before you try pumping fluid through the lines to the caliper.
Get loads of absorbant rag and wrap it around your master cylinder, and over any adjacent paintwork, just below the master cylinder banjo. Then crack the banjo bolt, just enough to let fluid seep out and push the brake pedal down SLOWLY. Hold the brake pedal down when it gets to the bottom, nip the banjo up then release the pedal. Do this two or three times and the chances are that any air in the master cylinder will now be purged. Then bleed your brake again from the caliper as normal to finish the job.
If the symptoms remain your seals may be naff | 
Jools
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