BHC550 Black imaging units.

[krazeekidz3]

HI!! Is anyone still having problems with the Black imaging units on a Bizhub C550. I have installed all the updates and this machine continues to go through Black IUs!!
The IUs last only about half of what they should. They seem totally fine, then all of the sudden they start dumping!!!
Has anyone found a cause or a solution?
Thanks!!

[YouthAttack]

they really are a pain. its worse if the customer prints large jobs. all i can think is probably flashing the firmware to the latest one.

[100spc]

The space between developing roller and drum was below lower limit specification. The centrifugal force causes the toner on the mag roller to be a larger diameter and creates toner build-up around the Drum unit.

I'm told this has been fixed in all IU's made since April 2009.

http://i51.tinypic.com/zwc2h0.jpg

[krazeekidz3]

Awesome, thanks! I'll try this the next time, before I replace the unit. Or should I increase the voltage before it happens?

The units that are going bad should be made after April 2009. One was purchased in Aug. 2010 and one in July 2010.

Thanks, again!!

[emujo]

Notice the poster said decrease. not increase...also there is some school of thought that the K IU is not seated firmly enough to the frame of the MFP. There is a mod that firmly pushes the IU back and holds it in place, but some techs have stated that if this is the cause, just putting a spacer between the lock handle and the IU does the trick. Emujo

[krazeekidz3]

Oops, duh, I meant decrease!! I do have the locking plate installed. Is this poster found on the KMBS website? If so, I must have missed it!!

[spock]

increasing clamp pressure or fitting locking plate helps alot but also add ECG-25 conductive grease to the rear contact pads to stop arcing also has also helped alot... The black IU's are forever prone to problems through with sucking dev, shadowing or P-14 skew codes but they are mostly fixed now.

If not fitting the locking plate, be sure to chock up the clamp on the black IU so it doesn't get knocked loose when changing the waste toner box and losses bias.