Need Help Yellow ink draining out directly into waste tank for no apparent reason

[JohnBoy1972]

We have a Mimaki JFX 500 2131. It has been a good machine overall. When we first got it about 6 months into ownership ... the yellow ink started being a problem. It was dripping out of the head and onto the substrate a bit, not a lot but worrisome. Anyways now the machine has an issue and the Mimaki reps can't figure it out. Basically you have to pull the chip out of the yellow ink tank when you are not using it, to prevent the machine from draining all the yellow ink into the waste ink tank. Makes no sense. Mimaki has not come up with a solution yet and it is causing huge problems. Any info to shed light on this matter would be greatly appreciated.

Thank You
John

 

[Solventinkjet]

Are you getting any error codes? Sounds like you might have either an air pressure issue or possible a bad subtank or subtank sensor to me.

 

[JohnBoy1972]

Are you getting any error codes? Sounds like you might have either an air pressure issue or possible a bad subtank or subtank sensor to me.

Yes air pressure problem, Just had all the subtanks changed out and one solenoid valve not sure what the name of it is but the subtank sensor might be the answer not sure if that got changed or not have to verify.

 

[Solventinkjet]

Yes air pressure problem, Just had all the subtanks changed out and one solenoid valve not sure what the name of it is but the subtank sensor might be the answer not sure if that got changed or not have to verify.

The first thing I would do if I was out on a service call for that machine would be to do an air purge to get out any air that may be in the system and then run the positive and negative pressure adjustments. If you can't get the pressure right and it isn't stable, you probably have an air leak or clog in the system somewhere. If it stays steady and within spec, everything should be good in that regard.