Refilling Cannon 106 cartrige streaks on page.

Question

I have been refilling a Cannon 106 cartridge with the tool kit. The first fill runs great; however towards the end of the ink the ink starts building up and streaking down the page; the text print is there however the whole page starts streaking down the page with a ink cast. Does this mean the roller is old? do they wear out. Why does the ink streak? Is there anything I can do to correct this?