[CQ] 6550C has colored streaks on grey background

[copierkat]

Hi all. Working on 6550C today, problem with colored streaks on grey background when printing (see pics). Streaks were on all colors when test printing 1/2 tones. Tried new transfer belt, no help. Working with just black, replaced k drum, grid, screened clumps from dev, scotched k mag roller, cleaned laser slit glass, cleaned 1st transfer roller in transfer assy, no help. Any ideas? Thanks

[Mr_Fixit]

Re: 6550C has colored streaks on grey background

Go into 04 mode and do a 231 on each color and see which colors are affected. Have you dis-assembled the laser unit and cleaned the mirrors inside the laser? I have heard that this has been necessary on the 6530's, I've seen this type of pattern on solids before and it is usually soiled laser mirrors.

[copierkat]

Re: 6550C has colored streaks on grey background

Thanks for the reply. I did a test print for each color, seems to affect every color. I did not take apart laser and clean mirrors, but will try that when I return. I ordered the 4 facing rollers for each color to try. Attached are pics of test prints for each color. Thanks

[Mr_Fixit]

Re: 6550C has colored streaks on grey background

That's a tough one, I was picturing light streaks when I suggested clean the laser mirrors but those halftones look like dark streaks to me and I'd go straight to the charge grid/drum etc but you've already tried that.

Hard to tell from the pictures but do the streaks line up through all 4 colors?

Have definitely had issues with the facing roller on the 3510c but that usually causes consistent fading towards the back of the copies, and anything transfer related should match up on all colors, is this machine in a dirty environment or has a lot of copies on it?

If the streaks are lighter than normal I think your looking at laser/transfer issue, but if they are darker then you are looking at a charge/drum issue

[copierkat]

Re: 6550C has colored streaks on grey background

Very clean environment. The streaks on the black test printout and grey print line up. Not so much on other colors, but hard to tell for sure. Thought for sure it was transfer belt, but like I said, made no difference when replaced.

[Mr_Fixit]

Re: 6550C has colored streaks on grey background

That really looks like dirty grid, do you have another machine you can swap the entire drum unit or dev out and see if it changes? 6550 uses different EPU kits EPU-KIT-FC65-G for CMY and EPU-KIT-FC65-S for the black, when you replaced the grids did you use the correct kits?

[copierkat]

Re: 6550C has colored streaks on grey background

I replaced the K grid and drum. Will see if I can borrow EPU assys from shop machine. Thanks