Hi , looking for a good Amal carb for my D10 or a new one possibly another make if it is a viable option , the throttle top on mine has lost the threads and will not tighten up think it's the thread on the carb body that has gone it's only about 5mm deep of worn thread which can't be correct is it ? and it just pops off , have had to tie it down with tie wraps which is not ideal 😄