Another Problem Ink going the wrong way.

[serverjohn]

Hey guys I have been searching in the archives and I am just not coming up with a solution.

I have a Mimaki JV3 160-SP.

I was changing out some o rings to hopefully solve some ink starving problems and stumbled on to another seemingly un related problem.

One of my yellow ink lines was empty! I have determined that this has happened somewhat recently just from the prints I have been running.

So I think maybe it is a bad cartridge. I replace with a new one and replace the o-ring since I had it apart. I got everything back together and start to draw the air out with a syringe.

Here is the kicker. after what seems like forever i get the ink into the damper. Whoohoo! Then after a couple second the ink gets drawn back up the line!!

Grrr.

Please help my head is going to explode shortly.

 

[housemusikid]

Do you have a large syringe? Sounds like air in the lines. If you do have a large syringe (like 60cc) attach a tube to the end of it and the other end on the damper that fits into the printhead. Pull back but do not put more air into it.

 

[serverjohn]

Thanks for the response.

Maybe I wasn't clear.

I drew all the air out with a syringe. When all the air is out I remove the syringe and the ink is drawn back up the line.

 

[housemusikid]

Thanks for the response.

Maybe I wasn't clear.

I drew all the air out with a syringe. When all the air is out I remove the syringe and the ink is drawn back up the line.

I AM SO SORRY! I was reading your post and talking to someone else at the same time. My apologies.

 

[housemusikid]

Have you checked pumps? The needle that opens the ink cartridge? The capping station? I am sure you have...just throwing out ideas.

 

[genericname]

The damper shouldn't allow air to come up through its opening, filling the line. The only this will happen is if the pressure of the air outside the line is much greater than the pressure inside the line. Either it's a bad damper, you still have o-ring problems, or it's at the feeding end of the cartridge.

Check the length of the needle in the cartridge assembly, and compare it with the needles in the working assemblies next to it. I'm willing to bet it's shorter, which would mean that the washer holding it in place has cracked, and the needle is now recessed inside the assembly housing. This can cause all manner of ink feed issues, and is usually the result of excess negative pressure, either from a clogged line that the head is trying to print from, or from one too many syringe pulls.

 

[serverjohn]

Solved...

I had an extra damper and it now works fine. Thanks genericname!

 

[MikePro]

did it fix your ink starvation problem?

if it wasn't the o-rings/dampers... it could be your capping station not making a proper seal to the head.

 

[dukeboy86]

Yes, most of the times when you pull ink on a jv3 and it goes up it's a damper problem not being able to maintain the negative pressure (because in this model the cartridges are at a higher point (thus less pressure) than the dampers.