Thank you both for your advice. an old and faulty diaphragm had occurred to me. The pen fills and expels 8-10 drops which IGriz used to say was about right. I have tried to blow down the filler and that didnt work.
Will give the pen 24 hours having given the cap a very good clean, if there is any more ink to be seen then the diaphragm must be the culprit.
Tom may have so opined, but he was wrong. You can not effectively measure the amount of ink taken into the pen by how much you get out of the pen. Take a look at this article that I wrote several years ago, and you'll see what I mean.
The cause of the problem could be a bad diaphragm, it could be that the feed is not set properly against the nib, it could be that ink is getting pulled out of the pen because the vent system in the cap is clogged, or it could be that you haven't filled the pen properly i.e. the last pump down, you hold it down and then pull the pen out of the ink, then release the pump. This clears the excess ink out of the breather tube and collector. If you don't do this, the pen may have a tendency to flood.
If blowing down the filler had worked, I would have been concerned. Between the pump rod and the inside of the pen is the diaphragm, which is water and air tight. Parker made a tool to test a diaphragm, which was a piece that fit into a bulb, and screwed onto the threads of the blind cap nipple. You screwed the tool onto the pen, immersed the pen in water and squeezed the bulb. If bubbles came out the tip of the pen, you had a bad diaphragm. If nothing came out, the diaphragm was likely OK.