Bizhub C253 K IU Problem

[minimerlin]

I am having a problem with the Black image units of this machine causing toner/dev to build up on top of the drum at the front of the unit (just 3inch wide.

Just wondered if anyone has had similar fault. I have replaced the iu a week ago after the origional one gave this fault, now I have to go back for the same happening again.

All units are inlife and not chipped. Seems like too much toner/dev at the front of the unit causes a wave effect which pulls the spillage with the rotation of the drum? I will try to get a picture tomorrow as it is hard to describe what is happening. Copy/ print quality is ok on the rest of the page just smudging effect caused by black at the front of the machine. (Looks a bit like the C550/650 K units do at the rear but this is the other way round!) IU is fully home and all connections are clean.

Any Ideas?

[konikilla]

Have you checked the machine with a spirit level?

[minimerlin]

Machine is level in both directions. Fault started a few weeks ago. Last week I find that the problem only occurs when running Thick stock..ie thick1 upwards, the thicker the stock, the worse the fault gets!

[konikilla]

It's sounds very weird. I would take a look at the secondary transfer if it is only happening with heavy stock. I would also the transfer cleaning blade assy. and check your laser unit is clean or just swap it with the one of the others.

[minimerlin]

I agree its a weird one, laser is clean, and the transfer all seems fine, am going to swap out the HV and connectors in case we have a corrosion problem. It has been suggested on another post to adjust the dev blade gap but that seems rather drastic! I will let you know my findings when I revisit next week..my brain needs a reboot I think! Thanks for your input, any assistance in this one is welcome.

[minimerlin]

I agree its a weird one, laser is clean, and the transfer all seems fine, am going to swap out the HV and connectors in case we have a corrosion problem. It has been suggested on another post to adjust the dev blade gap but that seems rather drastic! I will let you know my findings when I revisit next week..my brain needs a reboot I think! Thanks for your input, any assistance in this one is welcome.

Went back to the machine today and did the dev blade tweek as suggested....ran 400 prints on thick 3, 2 & 1
, no problem! I hope that is the fix.