Mimaki JV3-160sp - printing issues

[SbtVeroBeach]

Hey there!
So.. I am recently having some issues with the printer.
It's my workhorse, so with it being down, I am pretty screwed at the moment.

What it's doing:
It will print some things perfectly fine, full color, heavy ink, etc.
My test print strip is 100% on all inks.

Other times, it is printing, then half way through the print it acts like it's only printing at half color. Or a certain color ISN'T printing so there's a very noticeable color shift in the print and that specific print is ruined.
It goes from full color to a dulled out, grainy, half-color print. (I will attach a photo I took from a print job today)

What I've checked:
Naturally first checked to be sure all heads were printing 100% (they are)
I checked the pumps next - I checked to be sure the were working like they should. They do not seem to have anything wrong with them. I cleaned up the gears and some ink that had gotten back there, but that fixed nothing.
I can not visibly see any air in the lines, when I run a test cleaning the ink runs through the lines exactly like it should with no noticeable gaps or air pockets.
And like I said, the gears turn like they're supposed to.

Any suggestions on what my next step should be?
Could one of my pumps be going and I just don't see it since I have the machine closed up back there for printing?

 

[jfiscus]

I would say there is a leak in your ink system, in the lines or in the dampers.

 

[MikePro]

might be a pump/capping station issue, not properly refreshing the siphon-effect of your ink supply, and causing "ink-dropout" issues when the demand for ink exceeds the supply.

else, you could be running on an empty ink cartridge that the machine thinks is still full. as the machine senses the volume left in the bag in the cartridge, mechanically, via a trigger that could not be functioning properly.

 

[SbtVeroBeach]

Definitely can rule out the empty ink cartridge idea.
Those are good to go.

Is there a simple way to see if there's a leak in an ink line?
It does not just do it to one specific color.. it's done it on (the photos attached for instance) was 100% black, but will also do it on full color images..

 

[SbtVeroBeach]

I would say there is a leak in your ink system, in the lines or in the dampers.

Like I mentioned in my last reply -
is there a simple way to check this?
I changed out dampers on my yellow printhead this morning - so those are brand new.
I could change out the other dampers if needed...
But, about a leak in the line(s).. any simple way to check for that?

 

[SbtVeroBeach]

might be a pump/capping station issue, not properly refreshing the siphon-effect of your ink supply, and causing "ink-dropout" issues when the demand for ink exceeds the supply.

Any tests I can run on the capping station?
I know I have not replaced anything up there in quite some time.
I've only been running the printer the last year, but have been around it for 2+ and we have not changed any parts out on it for quite a while.
As far as I can tell just from looking at things, there's nothing visibly wrong or out of sorts. That's why I am having such an issue trying to figure this out.

 

[jfiscus]

You're gonna have to look under a loope and see what color is dropping out. And then go from there checking/replacing.
I don't know how to check, as we've never had this problem here.

 

[MikePro]

You're gonna have to look under a loope and see what color is dropping out. And then go from there checking/replacing.

most definitely looks like the black, as I don't see any hint of the rich-black CMY values in your disappearing print.

a good start to check if the pumps are working properly, is to run a buncha diswaywash cycles. if the capping station allows you to fill the caps with cleaning solution, pump them empty, and repeat... then you should be good.
if it were me, I would then confirm this by opening up the back of the printer to expose the ink pumps and running some fillupink cycles on the black channel.... observing whether the black ink is drawing thru the pumps properly.
this could also expose a capping station issue: during this operation, you may notice the black ink coming down through the pump/waste line a bit staggered/bubbly, compared to normal solid-streams of ink during normal function, as the captop is not making a proper seal with the printhead & drawing air in through gaps in the contact with the cap/printhead. if so, this can be attempted to fix-easily by slightly tugging up on the black rubber captop (not removing it, but slightly dislodging it from it's current position), and once the printhead carriage parks back on top, it should snug itself fit. (making note that capping station/printheads should be pristine, or at least free of chunky ink-buildup.)

keep the thread posted of your findings. love to hear if my jv3 rants actually help, even now almost 3 years since I last powered mine up.

 

[MikePro]

It does not just do it to one specific color.. it's done it on (the photos attached for instance) was 100% black, but will also do it on full color images..

damn, problems are usually easier to solve when i can isolate to a single printhead BUT this could possibly confirm ink pump issue... as one pump controls two ink channels. OR multiple captops on your capping station aren't making a proper seal.

 

[SbtVeroBeach]

damn, problems are usually easier to solve when i can isolate to a single printhead BUT this could possibly confirm ink pump issue... as one pump controls two ink channels. OR multiple captops on your capping station aren't making a proper seal.

Any idea what the general "lifetime" of the capping station is?
This printer has definitely got some miles on it, and as far as I know that's never been changed. If it has, only once.
Printer is about 7 years old - and has worked full time those 7 years.

I had the back of the printer open yesterday and while running just a "test clean" cycle all the hoses seem to be working exactly like they should.
I did not see any wet ink from a hose leak or anything. I also could not see any noticeable air bubbles or gaps in the hoses while the ink was pumping through.

When I run the daily "custody wash" cycle and fill the capping station with cleaning solution, I have no issue with any left over solution. It pumps through just like it should.
There's no puddle left over.

 

[SbtVeroBeach]

Another strange phenomenon that I notice (which potentially should have said in 1st post)
When I do run into the print issue I am having - where it dies out and looks to only be printing about half color - if I cancel the print, run a custody wash so I can clean it up, and also run a test cleaning (where the ink just pumps through and I am not adding cleaning solution anywhere), I can usually run the same print job that just messed up through the printer again with no issue.
But after I print one or two small to medium size jobs, I run into the printing issue on the next job...

This is why I am confused. haha
I can't figure out where the issue is originating.
Would the capping station be good for a couple print jobs then lose it's suction on the printheads once it's printing more?

 

[SbtVeroBeach]

Today's first problem.

 

[Solventinkjet]

Change the dampers and o-rings. Even if there is no air in the lines, the dampers can still be failing and causing the issue. Bad dampers cause most of ink drop out issues during prints. I also wouldn't rule out pumps and cap tops as they can look like they are working properly but it is impossible to tell if they are pulling the right amount of ink through. When was the last time you changed the capping station and dampers? If the answer is over a year, start with those parts first. They should be changed regularly anyway and it should fix your problem.

 

[MikePro]

+1 dampers & captops are a good place to start.
cheap parts to replace out of "routine" maintenance (i only replaced 3/4 captops, and about a dozen dampers during printhead replacements over the course of the 9 years operating that machine)
*noted, when/if you DO replace the dampers... be extremely careful to only pull straight up & insert straight down off the printhead. broken manifold on the printhead is a common result of being too rough with the dampers.

 

[SbtVeroBeach]

So I thought it'd be a good idea to print strips of 100% of each color (CMYK) - attached photos of the results.
Wanted to see if it was 1 color in particular..

The first pass, everything printed just fine. 100%
Second pass through the yellow started going, then the black and cyan.
I was hoping to pinpoint 1 individual pump if that was the case.. Looks like I can't do that since the yellow started acting up too. I believe the Magenta would've been next if I had let the print continue.
Does this look like it may be the capping station and dampers?
I just put brand new dampers on Yellow yesterday morning. -___- ugh

I find it hard to believe there'd be a leak in all of the hoses or anything like that..
I could be wrong.
Or maybe BOTH pumps are crapping out simultaneously?

 

[SbtVeroBeach]

Change the dampers and o-rings. Even if there is no air in the lines, the dampers can still be failing and causing the issue. Bad dampers cause most of ink drop out issues during prints. I also wouldn't rule out pumps and cap tops as they can look like they are working properly but it is impossible to tell if they are pulling the right amount of ink through. When was the last time you changed the capping station and dampers? If the answer is over a year, start with those parts first. They should be changed regularly anyway and it should fix your problem.

When I change out the dampers - is there anything else I should look for while I've got the carriage opened up?
I just changed the dampers on my Yellow yesterday. Unfortunately I think it's something more than the dampers since yellow is still going out on me.
*See my last post with photos of my CMYK test prints

 

[SbtVeroBeach]

+1 dampers & captops are a good place to start.
cheap parts to replace out of "routine" maintenance (i only replaced 3/4 captops, and about a dozen dampers during printhead replacements over the course of the 9 years operating that machine)
*noted, when/if you DO replace the dampers... be extremely careful to only pull straight up & insert straight down off the printhead. broken manifold on the printhead is a common result of being too rough with the dampers.

I've never done any maintenance or part switching on the capping station..
Fairly simple to switch out?
If it's multiple parts that need switched, would you suggest doing something before the other?
$$ isn't really an issue considering I NEED to get this machine back up and running. We'll do what we have to do..

 

[MikePro]

I've never done any maintenance or part switching on the capping station..
Fairly simple to switch out?
If it's multiple parts that need switched, would you suggest doing something before the other?
$$ isn't really an issue considering I NEED to get this machine back up and running. We'll do what we have to do..

yeah, really easy.
captops are just held in place by a cover and a couple screws ( each captop is spring-loaded with two standing-springs, be careful when popping cover as to not lose them!).
dampers just pull straight up & out, o-ring snug-fit. gentle, as to not crack the black plastic manifold these sleeve-onto. (best to power-down/unplug/discharge your machine by pressing the green power button a few times to remove any charges, remove ribbon cables, and place masking tape over ribbon cable ports for this. dampers drip ink and ribbon cables are really good at channeling a drop of ink down into the electronics of the printhead)

not 100% sure if these will fix your issues, but they're inexpensive parts that can rule-out a few issues when you know they're working properly.

 

[SbtVeroBeach]

I've never done any maintenance or part switching on the capping station..
Fairly simple to switch out?
If it's multiple parts that need switched, would you suggest doing something before the other?
$$ isn't really an issue considering I NEED to get this machine back up and running. We'll do what we have to do..

Thank you. Will try these options first.

 

[SbtVeroBeach]

yeah, really easy.
captops are just held in place by a cover and a couple screws ( each captop is spring-loaded with two standing-springs, be careful when popping cover as to not lose them!).
dampers just pull straight up & out, o-ring snug-fit. gentle, as to not crack the black plastic manifold these sleeve-onto. (best to power-down/unplug/discharge your machine by pressing the green power button a few times to remove any charges, remove ribbon cables, and place masking tape over ribbon cable ports for this. dampers drip ink and ribbon cables are really good at channeling a drop of ink down into the electronics of the printhead)

not 100% sure if these will fix your issues, but they're inexpensive parts that can rule-out a few issues when you know they're working properly.

Mike -
Is there different parts for the capping station?
Or am I replacing the whole thing?
I am looking on SolventInkjet.com and I only see the full capping station replacement.
Is that correct?