Blurry Black Ink Prints... Hardware Problem?

We installed a new black ink tank and now our prints are coming out blurry. Black prints only... Color seems fine. I've taken out the black ink and reseated it... It's an old Canon IP1000 printer. I've run the maintenance program and tried to unclog the print head but it still isn´t working right.

 

Hey superstar, take a looksee at this --> http://files.support.epson.com/htmldocs/pro76p/pro76prf/trble_5.htm

It is an epson site but i find it a good all rounder when it comes to printer probs like this.

 

may not be cloged, just mis aligned, if the printer or the sofware has a alignment page you can print, i would suggest it.