Cyan dropping out on Mutoh Value Jet 1640

[Production]

I am having a problem with my cyan dropping out of my Mutoh ValueJet 1640 once another color is introduced to the print. Does anyone have any ideas on how to fix this problem? It is happening on 2 of my printers, but not on the other two? We have already tried changing to a new batch of ink. Humidity is 45%. Replaced dampers. This only happens with cyan, and always when it gets to a different color.

 

[Solventinkjet]

We will need a little more information. Can you upload pictures of the issue? What does your nozzle check look like? How old is the maintenance station and head? Are you using a bulk system or cartridges?

Normally the culprits of drop out are dampers/o-rings and maintenance station but I have seen partially clogged manifolds cause the same issue.

 

[Production]

Sorry, new to the forum. Attached is the photo. After it drops out the left nozzle check is gone and the right is completely there. Bulk Ink. Head was replaced beginning of Feb, and I am not sure how old the maintenance station is.

 

[Production]

also, before I started this print, the nozzle check was perfect.

 

[Solventinkjet]

Definitely check your ink lines by taking the head carriage cover off. The lines should be solid colors with not even a small amount of air in them. The dampers should be about half full. If there is air in the lines, the damper is failing or the o-ring between the ink line and damper is failing. It could also be the bulk system failing but since there are so many types of bulk systems, it's hard to troubleshoot.

Also, if the maintenance station hasn't been changed in a year or two, I would replace it completely or just the cap top to save money. The maintenance station is responsible for pulling ink through the system and can cause some drop out issues if it is starting to pull weaker than it needs to. If you need parts check out our website: ValueJet 1604 Parts

 

[Production]

I will replace the o rings and see if that does anything different. The ink lines are full and we have done multiple ink charges to make sure of that. Thank you!

 

[Production]

That did not work. Still dropping out right when a different color is introduced. Same spot, every time. It can however print 40 feet of pure cyan with no problem, but once it comes to a "logo" or a different color, it [cyan] drops out.

 

[CRD]

All the 4 machines run from same rip station?
It looks inkflow on the printout is starving but if it Always happens at the same spot then it is rip or electronic related.
If print is 1 meter cyan and then other color and problem happens?
If print is 50 cm cyan and then other color and problen happens?
Just check that.

Paco

 

[devahoch]

Mutoh RH II One color drop-out

I have some problem for one head in RH II 64. When I check noozle, magenta droping out with all noozles, this problem still here with me. When I replace another head into this position ( head C/M) that print normaly, I think, problem is on head. Now I wait for new Manifold for replace old and test head. I can't print, only when I discontinouted magenta ink. Please, Help me!!!

 

[Production]

All 4 machines run from the same computer but I have two different rips. And I can print 1m and then a color and it drops out, but I can also print 50m then a different color and it drops out. It is only dropping out when a new color is introduced. And that color could be "white" or no color, and it still does the same thing.

 

[CRD]

If you swap both machines on the rips what happens, this is not a machine problem.

Paco