Kyocera 5250 stains

[Stefan Kraus]

Since 3 days I have some stains on my printings (see attached).
I did all the service programs but nothing works.
Do I have to change the drum?

 

[Obtex]

That looks like more a developer unit problem. The unit has a recovery blade next to the developer roller, after a long use, theese models tend to fill the gap between the roller and the blade.
A temporary solution is to vacuum the gap.

If that doesnt help. The next best thing is just to change the unit. The new units come with a upgrade so the gap doesnt build up