xerox 790 laser printer imaging problems

[johnrufus]

Hi. I have a xerox phaser 790 color laser printer. In the last few days it starting showing blotchy, white spots in the images, in whatever we print. Looks like a blizzard in the images. Had a service tech come out, found it was showing up around the belt area, could see a pattern on the belt, but not on the drum. They say we need a new belt, expensive and hard to get old one out and new one in.
Does anyone have any experience with this type of problem and what causes it? Wrong kind of paper going through it or something? How to fix it? Is the service tech right, or could it be the belt cleaner or something? Any suggestions would be appreciated.
Thanks,
John Taylor
Mid-Continent Printing

 

[CULTOFLON]

I saw something like this one time... It turned out that a piece of paper got wrapped around the 2nd bias roller... But surely the tech checked it?

 

[johnrufus]

Thanks for the tip. I checked it out, didn't find anything.
I have noticed that for some reason the images come out much better on thicker cover paper than thin paper, coated or not doesn't seem to matter. Maybe something isn't adjusting down to meet the thinner paper properly.
John