d4 shock rebound question

[dan_kitty]

is there a way to fill the shocks from the top and get a 3mm inwards rebound from pulling the shaft all the way out?

trying to do what it says in the tips from the hb website but filling from the top instead, but the shaft doesnt suck back in at all, so can only get rebound from pushing the shaft in, if that makes sense. Im guessing its something to do with air getting in when screwing on the top cap on.

and is it correct after pushing shafts in all the way they should only pop back out 3mm?

dont think ive ever got it correct

ta