UPDATE
It was the fuel filter. After the float hung a couple more times I went to the parts store to buy a new filter. After talking with the knowledgable clerk I realised my glass tube filter was missing the lock nut. It's supposed to hold the cylinder filter in place and seal it so the gass passes through the filter. Mine had no nut. The filter was laying in the glass tube doing nothing. It was sitting at the wrong end of the tube.
So.... I have purchased a nut to fix it. Will do so soon.
Just a little surprise left over from the previous owner.
