Arizona print nozzles falling out

[Classic1935]

Hi,

we have strange situation on our old Arizona 250GT print heads (Toshiba CA3 and CA4). It happens that the nozzles on more heads falling out on the same position. That's on the ink inlet area. At the start we can get back the nozzles with extensive ink purging at the start of print session. That's helps not long, over time, the nozzles in this area are permanently lost.
Any similar experience and solutions out there?

Thank's!

Classic

 

[ToTo]

Two possible scenarios: ink buildup in this area prevents from ink being fired. Visually inspect if you have ink collected in this area after nozzles get lost. Or missing ink in this region.
Check meniscus filter and replace. Could be also the small last chance filter in the printhead under the plastic cover.
Could be also a dirty air filter on the release valve of meniscus pump system down in the ink pump area.

 

[Classic1935]

Hi,

Thank's for your reply- The ink is missing in this area, We will change all the three filters. I will report the result.

 

[SignMeUpGraphics]

How long do you leave it before they block back up again?
This happens on our white channel only after a few minutes of idle, but never seems to happen to CMYK even after ~2 weeks idle.

 

[swordguy3222]

I've seen this on mine, I have this happen when ink makes it way up along the side of the print head, small seam along the outside of the head. Take a swab and place it in the area where you are missing nozzles, and hold it there. If there's ink build up, it will be drawn out by the swab. Might need a few, but it normally fixes the problem for me when I see this. Happens most with the white heads for me.