My printed page has yellow streaks on it. I have cleaned the roller mat, it just gets junked up again

replace the image unit for yellow and magenta

try this site for parts as a start

Precision Roller Printer Toner Cartridges Parts and Supplies Office...

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/normanj_7893313f0751935f

Run the printers maintenance software and run the align print head option and the run the clean print head option and check again and see if the streaking is still occurring.

Inspect the rollers for dirty or damaged surfaces. Clean up any loose toner or other debris in the machine. Note: avoid touching any roller with bare skin; especially in the fuser section or the photosensitive drum in the toner section. Skin oil can cause poor print quality or premature degradation of the roller surface.

That usually happens when a toner cartridge is getting low or old.
Replace the yellow toner cartridge. If you have done that then the other most likely solution is that you need to change the drum.

If you send a print job or print a report from the copier and there is no streaks then the problem is most likely the thin **** glass to the left of the large glass. It just needs to be claened.

If the streaks are happening when printing and copying then the problem is most likely your drum unit (MK-410) or possibly the fixing unit (FU-410), the fixing unit is the one that gets hot.

As the drum gets old it can cause print/copy issues and the cleaning blade that cleans the drum gets to the point it doesn't clean the drum properly causing streaks.

The heat roller has a teflon coating on it and as the roller gets older the teflon starts to come off and can effect prints/copies.

The drum unit should be replaced every 150,000 pages and the fixing unit every 300,000 pages on the KM-2050.

I hope this is helpful,
Shawn

streaking on the reverse side suggest dirty rollers.

1. remove cartridges form the printer
2. disconnect all cables
3. check full paper path for presence of debris, lint, bits of paper, remove if necessary (you can put printer on it's back or sides for esy removal)
4. mount on long skewers lint free clothing or tissue
5. wet tissue/cloth in isopropyl alcohol and whipe all rubber rollers on paper path till no discoloration to the tissue
6. connect all cables
7. insert inks and print test page

if necessary, you need to clean rollers again, but once is usually sufficient. to keep printer in good condition, you need to print at least one page per week and periodicaly clean the rollers, that depend on amount of printing done.

It's the waste ink getting on the exit rollers instead of going where it should. Canon has a mod for that where you remove the print engine clean the rollers and exit and install a mylar shield so it can't happen again. Probably too big a job for you to do at home..messy too.

The drum roller is damaged. You must be careful and spin the cylinder. do not touch the roller. You probably have a line in the roller that causes this issue. Each time i have seen this problem, this was the cause.

try the transfer belt/roller

The toner forms small lumps and get stuck on the doctor blade of the cartridge. Where there are the lumps it blocks the toner from getting on the roller. Removing the doctor blade and cleaning it with a soft cloth and alcohol can solve your problem.
Send me a mail at [email protected] if you need further help in doing it.