P9900 yellow acting up.

[dgberg]

Yellow drops completely off the nozzle check. A clean or two and it will partially come back.
Now on the yellow tests I am printing it starts the yellow than drops out completely.
Put a brand new OEM yellow 700ml cart in the event I had a cart pressure problem with my refillable.
Hope it is not another head. I have way too much K3 ink in stock to get rid of this thing now.

[Stephen G]

Can you show us the nozzle check print please?

[dgberg]

I can show you it but the yellow is completely blank.

[deanwork]

What is it with these yellow channels!

I’ve got an Epson 9890 with a yellow coming and going that’s driving me nuts  ( third party monochrome inks tyat don’t clog  ) and a 7890 with half the yellow missing ( Epson inks )  that I can’t get back without possibly removing the dampers which I really don’t want to attempt.

John

I can show you it but the yellow is completely blank.

[dgberg]

I can do a clean and get a little bit of yellow on the nozzle check. I then try to print one of the above images and get yellow to start but it drops completely out. Do another nozzle check and yellow nozzle check is blank like shown.

[tastar]

It could be that you got air in the line from a bad refillable. If a couple of paired power cleanings (or printing a solid yellow test sheet to pull yellow ink through the lines) don't fix it, then it might need a new damper assembly (selector unit).

[dgberg]

It is now printing again but I feel on borrowed time.

[deanwork]

If you hear an unusual sound with the pump every now and then  that means you have an air leak in one of the carts.

It is now printing again but I feel on borrowed time.

[Garnick]

Hello Dan,

When I bought my 9900 in Jan. 2010 I had no idea what a nightmare I was about to encounter.  However I will not bore you and others with the hoops I had to jump through along with Epson and D1.  At one point after the first head replacement (one of three in the first year) I encountered a similar situation that you might be up against now.  The yellow line connector from the cart was replaced as well, and then I had two air bubbles that I had to keep track of.  Occasionally they would cause the yellow nozzles to basically disappear in the nozzle check pattern.  All of this to say that you should be able to detect an air bubble in the yellow line if there is one.  Just use a high intensity light and follow the line from the cart to the head if possible.  The other lines are more obvious, but one can also detect an air bubble in the yellow as well. 

[dgberg]

Thanks, will check that out. It does pretty much the same thing. Prints good then drops completely. I have probably sent over 100 ml down the tubes trying to clear this.
My machine is also a 2010 vintage. I had the head replaced about 5 years ago so I have gotten my money out of it.

[deanwork]

Is it doable to fix this air in the line situation yourself. I think that may be my issue also with one of my printers using refillable carts. The nozzle comes and goes.

Hello Dan,

When I bought my 9900 in Jan. 2010 I had no idea what a nightmare I was about to encounter.  However I will not bore you and others with the hoops I had to jump through along with Epson and D1.  At one point after the first head replacement (one of three in the first year) I encountered a similar situation that you might be up against now.  The yellow line connector from the cart was replaced as well, and then I had two air bubbles that I had to keep track of.  Occasionally they would cause the yellow nozzles to basically disappear in the nozzle check pattern.  All of this to say that you should be able to detect an air bubble in the yellow line if there is one.  Just use a high intensity light and follow the line from the cart to the head if possible.  The other lines are more obvious, but one can also detect an air bubble in the yellow as well.

[Garnick]

Is it doable to fix this air in the line situation yourself. I think that may be my issue also with one of my printers using refillable carts. The nozzle comes and goes.

Unless it's somehow related to the pressure on the bladder, I've never heard of any procedure that would actually clear an air bubble in an ink line.  Of course that doesn't mean there is no such procedure, only that I've never seen it described.  At one point I also had a bubble in the orange line, but that one was easy to trail, so I knew that once it got close to the head I would probably see some negative results.  Interestingly enough, I never had any issue with that line, so I don't know how or why the bubble didn't cause at least one dropped nozzle, but it didn't.  I my opinion, if you do detect an air bubble, the only thing you can do is follow it along its journey until it get to the head and perhaps expect to see the results in your next few nozzle checks.

Of course it could perhaps be a damper issue.  in the 9900 there are no dampers as such but I don't recall the name of that particular part.  However it does basically what the dampers did before the 9900 series, so it could perhaps be an intermittent issue with that same part as well.     

[deanwork]

Called the ink selector unit. It’s a real hassle replacing it, IF you can get the part from Compas micro and they aren’t cheap at all. You have to drain the lines etc and hope you don’t break something else in the process. Then you could find out the pump is bad, or the head, or both.

If you do a google search for this you will find a lot of frustrated people trying to deal with this nonsense. I’m not going to work on these things anymore. The only way to own an Epson large format is keep it in warranty always.
or pay a fortune for a repair tech which most of the time they just start replacing parts until it works. It’s a sad situation all around. I really don’t see any sign of improvements in the P series from what I’ve read in these forums.

https://forum.luminous-landscape.com/index.php?topic=67136.0

Unless it's somehow related to the pressure on the bladder, I've never heard of any procedure that would actually clear an air bubble in an ink line.  Of course that doesn't mean there is no such procedure, only that I've never seen it described.  At one point I also had a bubble in the orange line, but that one was easy to trail, so I knew that once it got close to the head I would probably see some negative results.  Interestingly enough, I never had any issue with that line, so I don't know how or why the bubble didn't cause at least one dropped nozzle, but it didn't.  I my opinion, if you do detect an air bubble, the only thing you can do is follow it along its journey until it get to the head and perhaps expect to see the results in your next few nozzle checks.

Of course it could perhaps be a damper issue.  in the 9900 there are no dampers as such but I don't recall the name of that particular part.  However it does basically what the dampers did before the 9900 series, so it could perhaps be an intermittent issue with that same part as well.   

[datro]

Called the ink selector unit. It’s a real hassle replacing it, IF you can get the part from Compas micro and they aren’t cheap at all. You have to drain the lines etc and hope you don’t break something else in the process. Then you could find out the pump is bad, or the head, or both.

Yes, replacing the Ink Selector can be tricky, but it is doable, and it doesn't actually require draining the lines.  I replaced the Ink Selector and the head on my 7900 a few years ago and I basically followed the 7900 Field Service Guide document which indicates that draining the lines is "optional".  See page 98 of the FSG for a picture of how you wrap the tubes after removing them from the Ink Selector.  The key thing is that even after removing the ink line, it is still higher than the cartridges, so the ink will not drain.  Just wrap them as pictured to catch any drips and you'll be fine.

You will need four things to replace the Ink Selector:
- Ink Selector replacement (from Compass Micro)
- New O-Ring gaskets (2) (from Compass Micro) or clean the old ones before replacing
- Long phillips screwdriver to get to one of the screws on the Ink Selector (also ideally with a magnetized tip)
- Torque screwdriver for getting the correct torque on the screws which tighten down on the O-Rings when reconnecting the ink tubes (see the Service Guide document [which is a different document than the FSG] for the correct torque value)

You could probably get by without the torque screwdriver, but you need to be careful not to over tighten those screws, otherwise you may get leaks or blockage of ink flow.  Make sure to don't forget to put those O-Rings back on when reassembling!  Ink tubes connected without the O-Rings would definitely result in undesired ink inside your printer!

You need to be reasonably handy at doing this kind of work, so only attempt this if you can follow the FSG and Service Guide documents, prepare properly, take your time, and be gentle.  The Ink Selector is a bit fragile on the back side (closest to the head).  I would also recommend watching the infamous" Eric" video (here) which has useful information.

Generally speaking, if I had a channel (like the Yellow being discussed in this thread) that completely dropped and then comes back repeatedly, I'd strongly suspect the Ink Selector.

Dave

EDIT:  Just now realized that the original "Eric" video which used to be fully available on Eric's web site is no longer available.  Instead it looks like Eric has posted a short video that advertises his full video for a rental fee    ... Sorry about that...should have reviewed the video link before posting it.