Do you shake your carts occasionally? The carbon in the black channels can become unsuspended in the ink base over time and clog the dampers.
Two things I would do: First is I would try a black switch to the MK ( they share the same nozzle and line. ) But don’t do additional power cleanings.
If the MK looks good your dampers or line is not clogged. At that point I would simply replace the Pk ink .
If it is still clogged in the black channel with the MK ink, I would replace the “ ink selector unit.” This contains the dampers that filter impurities which often occur the most in the black channel due to the heavy pigment load. I did this and it brought back nozzles that were totally missing. This is a known situation in older printers. Some people replace dampers every couple of years.
The only reason to not consider all this is if your head is delaminated. If you have a nozzle check that shows warped or crooked lines in any of the channels the head needs replacing. One of the main reasons heads become delaminated is doing a lot of cleaning cycles in a seriously clogged head . That pushes pressure into the head and deforms it. I did that on one printer. It’s easy to become impatient and do these heavy cleanings .
Heads can go bad but most clogged heads are the result of clogged dampers not bad heads. Epson won’t tell you that.
If you need to replace the head and the ink selector I’d just spend the cash on a new machine.
John
Hello. I don't use my 9890 for high volume but print regularly. Finally have a black head clog and I can't get it undone. Have tried the Piezo liquid on paper towels, cleanings, new head scrapper, etc but I have a few middle rows in my PK that won't unclog? Any thoughts or tricks? Is it worth it to try to flush with Piezo fluid as its not cheap and could apply towards a new printer. Get a new printer? The added game and speed of a new printer are not a huge selling point for me so would prefer to fix mine if I could. thanks
