HP 570 Yellow Stops Printing

[lknmedia]

Hello!

Our 570 stops printing yellow ... or severely reduces yellow output after a few feet of printing. This happened soon after changing the large ink for both yellow and magenta. I can clearly see the banding and greys are purple/lavender.

Replaced both YM printheads even though all tests show fine. No change.
Replaced large ink with new yellow ..... no change.
Replaced optimizer ... no change.
Replaced intermediate yellow cartridge ... no change.

Not sure what to do next? Out of warranty and my tech hasn't been able to give me an answer yet.

 

[balstestrat]

And if you turn on spit bars on the side of your job, can you clearly see yellow going out?

Can you please run a job and post a pic of the spit bar where yellow goes out.

Make the bars wide so it's clear to see.

 

[cornholio]

Sounds to me like air has gotten into the system.
You can compare the actual y/m printhead weight with a working one. (C/K for example)
If it's lighter, then its likely air in the system.

 

[lknmedia]

And if you turn on spit bars on the side of your job, can you clearly see yellow going out?

Can you please run a job and post a pic of the spit bar where yellow goes out.

Make the bars wide so it's clear to see.

Thanks for the responses ...
I printed solid Y and it started banding.

Here is an example print showing it banding then eventually dropping out even more. Bottom of this print is the correct color.

I am thinking air as well ... How can I purge the air? Haven't been able to find detailed instructions online.

 

[balstestrat]

Before purging air you must inspect the ink like to see if there is a reason why air would enter and go all the way to the printhead.

The thing is, you replaced heads first and everything else after that. Now if the heads already have air in the or whatever, I would replace them again.
You can warranty the heads from HP for free.

I wouldn't completely disregard some other problem like electrical issue in carriage PCA (component warms up and disconnects) etc. It's not impossible however unlikely.