Ink gets sucked back into cartridge??

[Sante230]

Hey guys, First off, Sorry for only coming when I have issues and not really adding to the value of the forum. I'll start bumming around more often.

My Mutoh 1204 With OEM Inks New maintenance station and new dampers is have an issue with my black ink.

My ink ran out on black and the printer thought I still have 5 % left. I swapped ink and changed the dampers at the same time (Had new dampers and I figured I would need to do a little charge anyways.)

3 Little charges and 5 or 6 strong charges I am still having issues. I can fill the lines full of ink but if it sits for about 15 seconds it will start to drain back to the cartridge. I swapped back to a different damper and have the same issue. I checked on the orings and it looks like it in good condition. (Maybe they look good when they aren't?)

It seems to only be pulling back on one of the 2 black ink lines. Would a cracked manifold do this?

Thanks again for saving my butt guys.

 

[Solventinkjet]

If you didn't change the o-rings when you changed the damper, I would change those first and see what happens. The dampers keep the ink from flowing back to the cartridge. If there is an air leak, the ink acts like there is no damper and the o-ring is usually the point where air leaks occur.

Also, get a bright flash light and check the manifold for damage/cracks. Check the ink line for damage/cracks as well as old lines can dry out and crack. If all else fails, in rare cases the o-ring can pinch the ink line and create a divot which causes the o-ring to not seal the connection properly. You can cut the tip of the ink line off and re-connect the damper for a better seal. Note: I take no responsibility if you cut your ink line too short and the damper can't be placed back on the head properly!

 

[Sante230]

Thank you for the ideas! I changed out the oring and it solved my air in lines / ink retreating however now the dampers stay full but no ink will drop into the print head. I swapped dampers and it didn't change. It is my first black one that doesn't fill with ink regardless of what damper is in that location. If I manually put in down on the manifold it will print ok for a second till that ink runs out because it still won't pull from the damper. What might cause this issue?

 

[Sante230]

Problem solved. The new MS cap was not sealing around the head of the printer all the way. It sealed around all of them but the set of black ink on the head. I changed it for the old cap and it cleared up my whole problem.