C451 problem with black colour

[Zilviux]

Hi I got some problems when i printing images with a lot of black, the black makes dirty whole page even if 4x4 cm black logo it dirty around it! i attached how it looks. here http://www.osis.lt/problem.jpg
Also a lot of small "white holes" it wasn't before.
When i printing with alot of colours, and little bit black everithing is ok.

[minimerlin]

Are you an end user or tech? Have you set paper tray to match media type? Heavy stock if run as normal can cause toner not to fix correctly. Try running test prints in tech mode to check if it is just black (K) or manufactured black (c.m.y).

[Zilviux]

yes it's set thick 4 duplex. and here 100% black not black from cmyk. it doesn't matter heavy or plain, coated or not, this problem only when a lot of 100% black in print. first 2 prints it's good then goes like this. it was before, so was fixing by cleaning transfer belt, and knife for cleaning. (this done the guy from service) and works great, but now comes again it seems that this problem come when goes 100 000 copies.

[kmcopier]

did you install the fringe ? there are also some problems with the black unit drum distance from magnetic roller see your technical informations

[abilashvk]

Friend,
You can check the cleaning blade of black IU , or check the guide plate of fusing unit.Stop jam a Print and confirm it's coming from Dev, or fusing section.Also check the cleaning blade of transfer plate assy,( if needed).Is seems mostly because of cleaning blade of black IU ( check by interchanging the drum unit of black IU along with the black cap of IU--one screw beneath the label of black IU --and interchange the same with another existing colorIU along with the cap) and check

[Si@danwood]

I would say the black I.U is shot. Looking closley you can see chip marks and the smudgy lines are almost certainly blade leakage.If not the black I.U. then possibly the transfer belt unit as i have seen puncture marks causing the spots as well..Si

[Zilviux]

Thanks I'll check everithing today, also shows the code P-21, so maybe the blade don't do work good?

[Zilviux]

Ok i have cleaned it was a lot of dirty. And its help but after 100 goes like this http://www.osis.lt/problem2.jpg and its in same position everitmie but some just a little bit dirt next copy like this and all copies are different but problem in same position always.
May be is something wrong with fusing unit? (this is A3+ print)

[abilashvk]

friend
Hope the trailing edge of copies are smudgy(from your attachment).check guide plate of fusing unit as it may be contaminated with a thick layer of caked toner.STOP JAM a print intermitently to confirm any possiblity of transfer belt blade(less chances).Also the charge corona of black IU seems arching.replace/clean black IU.

[Zilviux]

so i remove one part from transfer belt and now everithing is ok