Hi Bernie,
The only rubber is a very short section from the fuel pickup to the first filter. It’s a brand new Citroen part from Franssen. The rest is either copper or SS braided PTFE – all brand new. The engine was overhauled by Michael Geary, perhaps there was a bit of crap in the fuel pump? (Not to speak badly of Michael – he did a beautiful job).
Cleaned it all out and refitted the float. All was good until yesterday. It looks like the float has jammed again. I still have the original carb, which is beyond economic repair. It dig out the original float and see if it’s better behaved than the new copy. It will also be a good opportunity to check for sludge!