We're at a loss for exactly what is causing this, but what we want to do now is eliminate every possibility that there is or was some form of chemical contamination or reaction that is causing a gelling of the ink inside of the printer or cartridge that might possibly explain this repeated issue. It does seem to be isolated at your location. So we want to make sure that you are not reintroducing something into the equation and that you are able to start from fresh. So, what we have done is formulated a new batch of yellow and we are overnight expressing this ink to you along with two new yellow cartridges and PiezoFlush. What we want you to do is start fresh in that yellow position on one printer by following these steps. It is important that you do not short cut this or you may recreate the issue again:
1) Discarding the yellow cartridge and ink that you currently have, fill a new yellow cartridge with the new yellow batch of ink (both of which you should receive tomorrow). This insures the ink supply at the cartridge is confirmed. Do not install this into the printer yet.
2) Install PiezoFlush into a new yellow cartridge (which you should receive tomorrow) and install this PiezoFlush filled new yellow cart into the printer.
[B]a)[/B] Disconnect the yellow line from the ink exchanger and pull PiezoFlush through the ink line with a syringe to clear out any material that may be in the ink line. This will confirm the ink line from the cart to the ink exchanger. You only need to pull through until the PiezoFlush is no longer being stained by yellow.
[B]b)[/B] Leave the PiezoFlush filled yellow cart in the printer at that point.
3) Replace the yellow damper with a fresh damper inside of the ink exchanger, or replace the ink exchanger with a fresh ink exchanger. This will confirm the yellow damper. But whether you replace the damper in the ink exchanger or the exchanger itself will dictate how you perform the next steps.
4) Reconnect the PiezoFlush filled yellow ink line.
[B]a)[/B] [I]If you have replaced only the ink damper[/I], run one Powerful Paired Cleaning followed by a Nozzle Check (to cool the print head) and then a second Powerful Paired Cleaning followed by a Nozzle Check to determine if the yellow print head channel is operable. This will confirm the electronics of the yellow print channel or the print channel itself, as well as the ink delivery supply system from the damper to the print head.
[B]or b)[/B] [I]If you have replaced the entire ink exchanger[/I], run the INITIAL FILL followed by a Nozzle Check (to cool the print head) and then a second Powerful Paired Cleaning followed by a Nozzle Check to determine if the yellow print head channel is operable. This will confirm the electronics of the yellow print channel or the print channel itself, as well as the ink delivery supply system from the damper to the print head.
5) At this point - the ink delivery supply system from the cartridge to the print head is confirmed. But, we will not know if the yellow ink channel in the print head is operable or not until you are able to successfully print the pink PiezoFlush through it. If at this point the yellow print channel is in-operable - the head must be replaced. If at this point the yellow print channel is operable the PiezoFlush can be replaced with the fresh yellow ink (from Step 1) at this time.
6) To replace the PiezoFlush with yellow ink, do NOT use Powerful Paired Cleanings. More than 2-3 can be harmful to the print head because it heats it up. Powerful Paired Cleanings are to be avoided like the plague in X900 and X890 printers as they are known to permanently damage ink channels when used excessively. If at this time, you have any doubts about the yellow channel because of excessive use of the Powerful Paired Cleanings - this print head should probably be replaced sooner than later to avoid premature failure (and these heads are already known for short life.)
a) Replace the PiezoFlush cart with the yellow cart prepared in Step 1). Run the Initial Fill from the Maintenance menu to replace the contents of the yellow ink line with fresh yellow ink. Best practice.
or b) Replace the PiezoFlush cart with the yellow cart prepared in Step 1). Use QuadTone RIP in Calibration Mode with a custom yellow target to print exclusively through the yellow channel until the pink PiezoFlush is replaced by yellow ink. Will not waste ink in the other ink channels.
At this point you will have discarded any previous yellow ink, and discarded the previous ink cartridge, scrubbed out the ink lines, replaced the ink damper, and charged PiezoFlush through the print head. You will have introduced freshly formulated yellow ink in a fresh cartridge through a clean ink supply system to the print head. If this works - we will get you set up on all printers with fresh ink.
Kelly has written you offline to make sure that only one cook is in the kitchen there (a technician to follow this through). We do not know who you are and there are at least three from your Company that have been communicating to us. So, please pass this on to the person who will be the technician on this printer (in the case that it is not you).
Please let us know if you have any questions about these procedures. We really do not want you deviating from these steps 1-6.