konica bizhub c451 blue deloper issues

hey guys,first post so dont get picky if i am doing anything wrong here.

i have the above mfp about 2 years now.thing is, it started leaking blue developer really bad.it starts by printing a blue ribbon on the entire bottom of the a4 page (about 250gr/m2). it is about 2-3 cm height by 21cm. after that it gets really bad.
the worse it got so far is about half of the page blue.after that, the developer gave up.i ve consulted with a number of technisians, changed blue developer units a few times, changed toner, had the mfp totally reset, bought developer in a bag to add etc. nothing really works. thing is i cant find anything online for this. has anyone dealt with this?

 

I have had excactly the same problem just with the yellow IU.
First, be sure not to run with that IU, because the developer falls onto some gears that are not easy cleaned or replaced.

Anyway, my problem was that the machine wasnt 100% level, so the developer ended up in one end of the IU unit.
I still ond understand why I only had problem with yellow.

Hope it helps a Little.