Asking for toner........ put a km5050 toner tk717 into the machine and the coupling that drives the toner ctg is too big, wil not add the toner. put a cs 5050 tk 719 toner in and the same deal what the f---. is this i machine differnet from the standard km and cs series machines. the gears at the rear of both toner ctgs look identical and the coupling gear i speak of is on page 34, fig 17 part #12 in drive unit 1 section. help appreciated. thanks t