Hi Grumpy, I finally managed to get a look at this. Only this afternoon I removed the carb and then the blower housing. It is rigid btw and there is a shaped recess to accommodate the carb bowl. There is no give at all. There is a small rub mark on the housing where the paint has gone back to bare metal.
I removed the blower housing and judging by the bolt heads and marking etc, it hasn't been off before. The gaskets either side of the insulator look fine. I positioned the housing without doing the bolts firmly. I reinstalled the carb and then tensioned the bolts to the blower housing. There is just under 2mm clearance where before there was none. Everything seems to sit as it should.
Ran and tested and its still having the same issue. Only runs on almost full choke. It really hasn't changed at all.
Back to inspecting the carb again.
