Hi NormK,
Yes filing the crown is the same thing as pushing the seat further in by 1mm provided that the float won't hit the body when closing the valve. Best not to file the crown tip. After you've talked about clearance, deflection or float travel, last night looking closely on the different floats, I realised that the floats that we manufactured is slightly shorter than the genuine or any aftermarket floats means more clearance, deflection or travel to allow the needle to drop further down. Maybe this is also the reason why I didn't encounter that sort of problem on all my repairs. Hope you still have the sample float I sent you to try.
Cheers,
TheCarbyMaster
