ValueJet 1614E Magenta and Black printing problems

[FaneDuru]

We print on Valuejet 1614 since 2011 without big problems. From a couple of weeks we started to face printing problems on Magenta and sometimes on Black. The printer behavior is the next.
It starts OK and after some time (about 3 to 10 sq meters) red color (100% M, 100% Y) starts to become Orange with missing of magenta lines. Very seldom this is also happening on black color. I would like to mention that the problem appears at the end of the red part. I mean the nozzle do not have dried ink, the ink does not go out any more. The nozzle check looks very bad on Magenta and bad on Black (even if the appearance of black did not change visible...).
After one of two normal cleanings the nozzle check looks OK and we can print again for a period of time.

' We are using Onix 10.0.0.89 installed on XP computer.
' The print head has been changed less then two months before.
' The dumpers of those two colors have been changed and also theirs O-rings.
' I can not see air on the ducts.
' The intermediary tank is full.
' I cleaned the head itself gentle pushing cleaning liquid through Magenta nozzles (using a syringe) and sudden pulling the liquid. After this operation it looks that works well for a little more time. But it may be connected with the strong cleaning done after...

I am out of ideas and we have a big order which must be finished during the weekend. It is frustrating to stay all the time near the machine and clean when the problem appears not having ideas about the origin of the problem... Especially during the night.

Any idea will be much appreciated!

Thanks in advance,
Fane

 

[wunder]

you say..after cleaning seen all good......so i think the troublemaker can be the damper....to check it please use new damper and print again...otherwise you can check it by printing unidirectional "slower and the damper can regenerate the ink level inside".....other printing with Print & Wipe function......is your problem solved with unidirectional printing...renew Damper again....

best regards
wunder

 

[Jeff South Florida]

my first thought is to replace dampers. I would the pull ink to the damper with a syringe. Then watch to see if the ink retracts from the damper back to the sub-tank. This would tell me there is an air leak somewhere.

 

[FaneDuru]

you say..after cleaning seen all good......so i think the troublemaker can be the damper....to check it please use new damper and print again...otherwise you can check it by printing unidirectional "slower and the damper can regenerate the ink level inside".....other printing with Print & Wipe function......is your problem solved with unidirectional printing...renew Damper again....

best regards
wunder

I changed the dampers of that two colors. I did that the day before yesterday... When I did that I also replaced the O-rings. Do you mean the dumper can be wrong?
I will try to 'regenerate' the ink level printing unidirectional. Now we (try to) print bidirectional (Onyx) with Maktac banner 2 profile, wave 2.
I would try also Print & Wipe but I do not know how to do that... I would like to mention that the level of ink inside dumper (visible side) is about at the middle of it. What is strange is that the level of Cyan is lower but we never had problems with that color...

Thanks for your interest in helping me!

 

[FaneDuru]

my first thought is to replace dampers. I would the pull ink to the damper with a syringe. Then watch to see if the ink retracts from the damper back to the sub-tank. This would tell me there is an air leak somewhere.

I pulled ink through the down side in order to fill the damper (using a syringe). I did not follow the ink retraction trying to insert the dumper in the head connectors as rapid I could. When I dismantled the dumper, even if I tried to strangulate the pipe (with a medical clamp) the ink migrated towards the sub-tank. I mean the air went in that direction... Is that a sign that it may be 'an air leak' somewhere there? When you say 'an air leak' do you mean a wrong connection where the air can go inside or a small air bubble remained in the system (maybe inside sub-tank...)? If yes, how would I take it out? In the past I pulled all the ink of that tank, the handle of the syringe could not be pulled any more. I had to start the machine, I received the error message saying that the sub-tank is empty and I could do the dumper filling only after that... Is that a way to take out the air?

Thanks for helping me, too!