Mimaki JV 33 - 130 | Both yellows are not working

[Sage Print and Sign]

Hello,

We have a Mimaki JV 33- 130 Printer , its an older machine and for some reason the yellow ink is not printing, it sometimes prints a few lines then it stops and the yellow dampers look somewhat empty on both sides of the print head. We have done the following troubleshooting and i am hoping someone has another idea that we can try out.

1- Ran Cleaning soft, hard and overnight print head soak and 80 min soak.
2- replaced the 2 yellow dampers about 6 months ago and waiting for new dampers. When i hold the damper button and the button behind the ink cartridge, the ink doesn't go through into the damper.
3- replaced the nut and washer that connects the hose to the white connector above the damper.
4- swapped the white connector with a different connector from a different colour and that colour is still working fine.
5- ran cleaning solution through the hose for both yellows and removed any air that could possible be in the line by using a syringe and the ink was flowing nicely.
6- replaced the capping station
7- the pump was replaced about 2.5 years ago or so but we ordered a new pump
8- The print head was replaced 2.5 years ago (the whole assembly, head and chip)

If anyone else has any ideas then please let us know.

 

[Neil]

Unplug the 2 yellow dampers from the head and swap them for the cyan. Plug the yellow dampers into the cyan head nipples and vice versa.
See if the cyan ink will print through the yellow channels to verify that it's not the head or electrical related. It's probably not.
Check the cap seal is air tight, pump tubes are flowing and no air leaks under the cap. It's probably that.
Go into service mode and open the yellow cartridge valves. unplug the yellow dampers and pull ink through. Invert them so the air goes out the top.

 

[Forty One]

I had the needle that goes into the ink cart get all gummed up and the valve wouldnt open/close properly.

Sounds like you have a supply issue. Try swapping the dampers around in the different channels.
This will confirm tht the head is good, also the dampers and captop.
Prime the dampers with ink and see if the head is printing via test prints etc.

I ended up disasembling the entire ink feed from the cart down to the head. Replaced the ink line, dampers... the whole lot. Then I checked that tiny valve on the cart.
Little soak and pushed fluid through it with a syringe. problem sorted.

Now, that may not be the solution to yours, but do the problem solving and you'll find out where the problem is

 

[Terry01]

Check and ensure the ink solenoid is energizing and opening..You can jam them open for a test.

 

[DL Signs]

It won't flow ink into the damper unless the valve is open. If you take the panel off the back side behind the ink cartridges you'll see all the solenoids that open the valves, first run a print with nothing but a yellow square and see if the yellow ones are opening, if not you have either a bad solenoid or electrical problem. If it's opening, you can hold it open it by pressing on it, have someone hold it open, or tape it open, then see if ink will run into the damper while it's open. If not, then it's most likely a bad needle valve where the ink cartridge attaches, or it's gummed up, or there's a blockage in the line.

My first hunch would be a needle valve, they're a mechanical wear item, and do fail from time to time, more often than the solenoids. Good news is if it's a solenoid or valve, they're not very expensive, and not difficult to replace. SoventInkjet (a merchant member here) sells them, and gives awesome support. The solenoids are around $25, and the needle valves are around $40, they also sell ink lines if that's the problem.

 

[Sage Print and Sign]

Unplug the 2 yellow dampers from the head and swap them for the cyan. Plug the yellow dampers into the cyan head nipples and vice versa.
See if the cyan ink will print through the yellow channels to verify that it's not the head or electrical related. It's probably not.
Check the cap seal is air tight, pump tubes are flowing and no air leaks under the cap. It's probably that.
Go into service mode and open the yellow cartridge valves. unplug the yellow dampers and pull ink through. Invert them so the air goes out the top.

Thank you! i tried this and both Cryan and yellow stopped working. We got our new dampers in today so i replaced them and ran a nozzle wash and it looks like Cyan is slowly coming back again.

 

[Sage Print and Sign]

I had the needle that goes into the ink cart get all gummed up and the valve wouldnt open/close properly.

Sounds like you have a supply issue. Try swapping the dampers around in the different channels.
This will confirm tht the head is good, also the dampers and captop.
Prime the dampers with ink and see if the head is printing via test prints etc.

I ended up disasembling the entire ink feed from the cart down to the head. Replaced the ink line, dampers... the whole lot. Then I checked that tiny valve on the cart.
Little soak and pushed fluid through it with a syringe. problem sorted.

Now, that may not be the solution to yours, but do the problem solving and you'll find out where the problem is

when i put in the dampers, i was able to get ink flowing smoothly. I also did notice some ink on the yellow needle where it plugs into the cartridge so i cleaned that too.

 

[Sage Print and Sign]

It won't flow ink into the damper unless the valve is open. If you take the panel off the back side behind the ink cartridges you'll see all the solenoids that open the valves, first run a print with nothing but a yellow square and see if the yellow ones are opening, if not you have either a bad solenoid or electrical problem. If it's opening, you can hold it open it by pressing on it, have someone hold it open, or tape it open, then see if ink will run into the damper while it's open. If not, then it's most likely a bad needle valve where the ink cartridge attaches, or it's gummed up, or there's a blockage in the line.

My first hunch would be a needle valve, they're a mechanical wear item, and do fail from time to time, more often than the solenoids. Good news is if it's a solenoid or valve, they're not very expensive, and not difficult to replace. SoventInkjet (a merchant member here) sells them, and gives awesome support. The solenoids are around $25, and the needle valves are around $40, they also sell ink lines if that's the problem.

yes, it flows into the damper when i hold the valve down. could the needle be clogged on the inside and it's not taking enough ink?

 

[Smoke_Jaguar]

Sometimes the rubber seals in the solenoid valves swell and don't flow ink well. Instead of using your hands, have someone turn the valve on in the #Test menu with the line disconnected and a container to catch the ink held below the valve. Not going to spray out or anything, but it should drip decently quick (multiple drops per second, or a thin stream). Using your hands to press down the valve as opposed to the solenoid might be biasing your test as the amount of force might be much more than the solenoid actually applies. If you have flow, odds are your needle/valve/solenoid are fine. If you have low flow, you'll see ink cutting out mid-print as the dampers cannot refill quickly enough.

If you're comfortable with it, the solenoid valves are just held together with Philips screws and can be dismantled and cleaned. On printers with subtanks (not this model, uses dampers), we will clean up the ports, wipe down the seals and re-stretch the springs a bit so they seal better.

These heads absolutely require a good ink priming, so check and doublecheck the cap to make sure it is sitting right. When doing a cleaning cycle, watch the tubes to see if ink is being drawn through the system (if the lines aren't clear, stuff some paper towels in the top of your waste tank to see if they get covered in ink). Since all channels on the head share the same capping station, if 3/4 channels are flowing freely and one is not, those 3 channels will flow and take up the vacuum before the other ones. Essentially, the flow has to be somewhat balanced for all channels to prime properly.

 

[Neil]

Thank you! i tried this and both Cryan and yellow stopped working. We got our new dampers in today so i replaced them and ran a nozzle wash and it looks like Cyan is slowly coming back again.

It'll be your cap seal, like it always is. Have you cleaned around your head edge? checked your cap top?

 

[Forty One]

swap the dampers around. That will tell you if the ink flow is the problem or if it's a capping or head issue