Nat, i will have a go again when it stops raining, i will measure all my needles with vernier and use smallest/loosest one.
I have also been told that its not unknown for the overflow tube thats fitted in the float bowl to have a tiny split in it ! there fore it would leak even iff needles are all ok.
I have a spare set of 900 carbs with bowls and needles to use. I cant put the 900 carbs back on because they are in 100 pieces now .
thanks for advice.
ps, catch tank isnt a lot of work, its a small empty plastic bottle .