xerox 700 black streaks on image

[lion_heart]

Good day, having some quality problems with my images once black is a part of it. by the pic if you look in the middle of it there are streaks on the (k) takes up about 35% of the image. if the image is a full black, the streaks cannot be seen, but once it gets to a shade of anything less than 80% or so of black it is very visible. I had one tech came in, he cleaned the laser to the top of the black, didn't work, his estimation was the laser might be faulty. A different tech came in and said he believes it is the 1st BTR (k) roller 059k79210 and said to try changing that. Is there anybody there with other suggestions? and aslo can't find 059k79210 online when looking for that part. is that the right part number for the 1st btr k roller? help and suggestions please. thanks


black-quality-sample.jpg

[Exok]

Have you tried a new black drum cartridge? If the laser unit window was dirty it would cause you to get void streaks in black as well as if you have a problem in the black developer unit or the 1st (K) BTR roller. It looks though that you have streaks that are darker than the image intended so I would not suspect laser or 1st BTR. Possible poor IBT cleaning , 2nd BTR cleaning but most likely the black drum.

[lion_heart]

Have you tried a new black drum cartridge? If the laser unit window was dirty it would cause you to get void streaks in black as well as if you have a problem in the black developer unit or the 1st (K) BTR roller. It looks though that you have streaks that are darker than the image intended so I would not suspect laser or 1st BTR. Possible poor IBT cleaning , 2nd BTR cleaning but most likely the black drum.

yes i tried two different drums on this item, the tech also tried a developer (k) unit out of a 7775 that I have here just for a sample print to check problem, and changing the developer unit didn't work either. Poor IBT cleaning means what? change the cleaning mechanism or ibt belt and the cleaning mechanism?

[adriansto]

Print a 40 -50% black test page from machine service menu.
Stop panic the machine and inspect how the image on IBT looks. At 50% densities you will see if the streaks are there. If they are, then change or clean the charge corotron or do same thing for black btr1
If they arent then try to change 2ndBTR.

[Jake2o]

Is it only on black images? Or can you see it on all colours? do a test print number 12 and number 13 or print a page with C,M,Y,K bands on it.
If it is only in one colour then you are looking at something that is for that colour only:-
1stBTR K
Drum K
Developer Housing K
Developer K
ROS unit K/C (they are paired so one unit for 2 colours)

If it is in all colours then you are looking for something common to all colours:-
2nd BTR
IBT belt
All the 1st BTR rollers

An IBT cleaner failing would result in dirty dark or brown marks being visible on prints on top of the image but wouldn't necessarily cause this streaking fault.

When you do a 100% black print it is using more toner then on a 50% tint so it may be very early stages failure of part/s

Have Fun !!!!!

[lion_heart]

Is it only on black images? Or can you see it on all colours? do a test print number 12 and number 13 or print a page with C,M,Y,K bands on it.
If it is only in one colour then you are looking at something that is for that colour only:-
1stBTR K
Drum K
Developer Housing K
Developer K
ROS unit K/C (they are paired so one unit for 2 colours)

If it is in all colours then you are looking for something common to all colours:-
2nd BTR
IBT belt
All the 1st BTR rollers

An IBT cleaner failing would result in dirty dark or brown marks being visible on prints on top of the image but wouldn't necessarily cause this streaking fault.

When you do a 100% black print it is using more toner then on a 50% tint so it may be very early stages failure of part/s

Have Fun !!!!!

it's only on (k) i did the cmky test the bands are only showing on the (k) i ordered a 2btr, and new devloper housing and also 1st btr rollers, hopefully they will be in by next week and will keep everybody updated. for purpose of helping out the forum i will change parts one by one, and let everybody know what is the problem part. thanks guys