xerox DC 260, strange cyan color streak problem, any ideas?

Dear xerox experts,

My xerox DC 260 printer has a cyan process direction streak problem. When printing a 960-SRA3-click job (80 booklets) the first 4 booklets (48 clicks) come out fine. In the 5th booklet however a massive streak suddenly appears in the bottom of the page.

After several hundred clicks the streak becomes slightly less visible. This pattern repeats itself (I have seen it throughout several print jobs). K-only prints come out fine.

One additional problem: the 2nd booklet from the bottom (see attachment) shows a lack of yellow toner coverage (gradually gets worse towards the bottom of the page). A am assuming this is not corellated to the first problem.

I attached an image showing 5 booklets coming from this job. It seems that the streak severity depends on the surrounding toner coverage.

Any ideas about how to solve this? I suspect a ROS related problem, but could it be something else (dev tank, drum)? Sorry about the long question, but many thanks in advance!

link to higher quality image: http://i.imgur.com/qAIeyLi.jpg

 

I'm not an expert, but have put a lot of time on a similar machine, a 242. Our ROS issues didn't get better and worse over a run - because of this I'd suspect a drum or developer housing issue first. And those are much easier to troubleshoot.

First you can swap the color drums to troubleshoot very easily so move the color drums one position and see which defects follow or not. Then you can also temporarily move a developer housing between colors to troubleshoot. Block the opening with tape so the toner color inside doesn't get mixed and run a couple prints to see if the defect follows, then swap back. (don't run much this way, only a couple prints to test, not enough for the toner to pile up and cause a problem.) It takes less than 15 minutes... just be careful not to drop any screws

 

Many thanks Jeff for such a quick answer! I will be doing this tomorrow, now let's hope the ROS is ok....

 

Thanks Jeff! It worked! When I moved the drum the defect followed (now the streaks are magenta). I put the defective drum in Y (for the time being). Will be ordering new drums. Surprised though, drum was supposed to have a lot of life left.

 

Excellent.

We usually got pretty good yields out of the xerox drums compared to the machines we had previously, but I did appreciate the fact that the color drums were interchangeable.

We ran mostly runs of 1000+ 11x17 and 12x18 size and photographic content on the color sheets, about half color and half black and white prints. Not too often, but sometimes I would get a line defect on either the cyan or magenta with around 30% yield left and would swap drums so the defect wasn't where it showed since I usually couldn't detect the defect with the drum in the yellow slot for general prints.