C6500/C6501 Black spots on Black Drum

[seniortech]

Becoming a joke now another 3 black drums on 3 seperate C6500 machines today with black spots all over them, tried cleaning as Stirton M suggested, ok at first, but spots were back after several hundred prints, had to resort to changing the drum to cure problem...

[jma676]

Becoming a joke now another 3 black drums on 3 seperate C6500 machines today with black spots all over them, tried cleaning as Stirton M suggested, ok at first, but spots were back after several hundred prints, had to resort to changing the drum to cure problem...

Maybe you have another problem and not the Drums Unit, if you refer a.. One black dot on the surface of the drum.. that yields a white point on the print image according to where it is located.

If the case is many black dots on the image, maybe your problem is the toner or developer.

With a sample image would be easier.

[maily]

Try to change the paper gms on the setting,if missing you need to replace the developer due to overlife span ,co's u reset the counter.

[mapracing]

We have an account with a C6501 that is having the same black mark issue on the drums. We have replaced the Drums several times, Developing units, Developer and corona assemblies. This looks like the same problem with the bad drum lot from awhile ago. If anybody comes up with a solution please let us know.

[Tonerjockey.com]

Wonder what would happen if you swapped one of the color drums for one of the black? Would the spots stay with the drum or would new spots develop on the black drum?

[mapracing]

We have done that it develops with the black drum. We also get it with the color drums but not as often. We went back today and replaced all the filters and vacuumed all the duct work thinking that it might be a heat problem but only time will tell at this point. We did notice that one of the ventilation ducts was clogged so hopefully this helps and the customer allowed us to put a fan behind the machine to blow more air through the filters.

[Tonerjockey.com]

The clogged ventilation makes sense.

[Stirton.M]

I would agree with the ventilation as well.

Though I haven't had this problem in some time, I have noted that on occasion that if I see toner dust building up in and around the process carriage, this is a strong indicator that the toner/ozone filter box on the right side is likely clogged and needs new filters. These should last 200K as they come with that kit, but this is not always the case. I keep a bunch of these filters in my trunk stock for just such occasions and make a mental note to check during calls for other issues. As I said, I have not encountered this drum problem in some time, so the filter changing might be a factor in keeping that issue at bay....or simply a coincidence...I am not sure...aside from knowing that I rarely have to clean the process carriage area to the extent I would have to with severely clogged filters.

[mapracing]

I will keep you guys posted if the filters and cleaning the air ducts did the trick as we are keeping a close eye on this machine.

[racefreak]

I've had this same issue on all my 6501s (only model and the like I work on). All drums are the 102c and I have no fuser exhaust filters and I keep the toner filters clean. These specs show up regardless of age of the drum unit. Some show up 10K after being replaced, others 100k or never. Being in the southern US, humidity is a big factor. I clean the offending drum with alcohol on a t-shirt rag and then replace the drum with a color unit (usually yellow). Make sure you run the set up adjustments and most times it won't come back. If it does, replace the unit. FYI...The toner filter has 8 of the white cloth filters in front of the single ozone filter. If you remove 1 or 2 of the white filters every time you go, by the time you run out, it will be time to replace it according to the counter.

My understanding is SSD is still working on a permanent fix but this seems to work for me.

[HORSE]

Try swapping the black drum with drum that's in the magenta position and putting a new drum in magenta instead.

Wouldn't waste you time debating filters, it nothing to do with that.

[mapracing]

As racefreak has stated. SSD has confirmed there is a problem with the coating on the drums and it has been escalated to Japan. I will keep you guys informed once they respond to my ticket. For now we are just replacing the drums in the color unit and using that drum for Black.

[Stirton.M]

Just had a chance to review some of my course material related to the 6501 differences to the 6500, and according to that, the drum units for the colour were DU-102, and the black was DU-102B.

That said, we are now up to DU-102C. And of course, we, in my shop anyway, did not make any distinction between them. We stuck the same drum in all colours and simply kept an eye on them. It is rare that we get them now....likely due to the changes made to the DU-102C over the previous generations...the older ones, we suffered a lot of blade flipping, spots on the drum were not so much the problem. we compensated the blade flipping for a time by using the blade and plastic couplings from a C500 drum unit, which seemed to resolve both issues.

[Duppsko]

I've had the same problem with one of my machines. But it was always on the yellow drum. Replaced the drum, and it could work for some days or weeks. This was solved when I took a PM and changed the developing unit at the same time. Now it has worked fine since the PM.

[Trek]

Dont think its the drum surface

We have this issue on 2 6501's, we changed the DU-102C in the black position for an old DU-102B but the problem came back.

All developers are changed, all filters clear, fans working ok, ventilation good. Copy quality adjusted properly, but the issue comes back after 2500 prints.

Does anyone have the definate fix for this?