Need Help Random Ink drop out VS-640

[2B]

One of our VS-640 printers is acting up and we are unsure the cause.
we have been experiencing random color drop outs and then we can run a combination of manual and menu cleaning. then all is good and we have full nozzle firing

the printer is running OEM Inks with an 6 color configuration Lc-C-Lm-M-Y-B-C-M

the print head was changed March 2016, along with all of the dampner, wipers and cables
about a month ago the dampers, wipers where changed again.


yesterday we had full print nozzles.

this morning did test print and one of the M heads was acting up.

started printing a banner and got about 7 feet into the print then the Black channel dropped out.

tried doing numerous cleaning and as you can see some of the channels would come back and then go away


before we buy another print head is there any suggestions on what / how this happened and more importantly how to fix it.
banner 7 feet print
banner 7 feet print1
Post Banner 1
Post Banner 2
Post Banner 3
Post Banner 4
Post Banner 5
Pre Banner Test

 

[2B]

If you hover over the thumbnail you can see the file name which also tells the order of the images

The Capping station was changed when the dampers were changed

 

[Joe House]

If you syringe from below the captop, do you get air or ink or resistance?

 

[2B]

The production manager has not tried pulling ink through the capping station using a syringe.

So far he has pulled ink into the dampers when the dampers are off of the head with a syringe, then reattaching the dampers to the head and then doing a medium clean to pull the inks through into the capping station

 

[2B]

he just tried pulling the ink through the capping station with a syringe (machine on and off) and there is constant resistance on the syringe

 

[Joe House]

Does any ink flow through?

 

[2B]

whenever a head clean is selected on the menu option then yes there is ink on the capping station and in the drainage bottle

trying to do so with a syringe, on the bottom of the capping station, then no all that happens is line resistance and no ink

 

[Joe House]

Are you syringing from the captop directly or doing it from below the pump? If ink comes through when doing a cleaning then it should come through with the syringe. If you move the head out of the way and put some cleaning fluid in the captop, can you pull that through?
If he's been removing the dampers, the o-rings could be missing or otherwise jacked up. Also, if you look at the nozzle plate, are there any signs of damage? or scratches?

I'm just trying to think of things to look at. This is a bit difficult without the printer in front of me. I hope this is helping.

Joe

 

[Joe House]

Something's amiss here. If ink flows through to the waste ink bottle when cleaning, it should flow through when pulling with a syringe. Are you pulling directly from the captop or trying to pull through the pump? If you move the carriage aside and put cleaning fluid on the captop, can you pull that down with a syringe?
Do you see any signs of a head strike when looking at the bottom of the nozzle plate? If he's been pulling the dampers out, the o-rings could be missing or otherwise jacked up. Check those out.
Also, on the VS, there's a manual choke valve that closes all the lines. There's a sensor that should tell the printer if it's in the closed position and alert you to open it though. It's on the left end of the printer (I'm thinking on the outside wall) there should be a hole that will take a 4 or 5mm Allen wrench that will open or close the valve. (But again the sensor should tell you whether or not that is open or closed.)

I'm just tossing stuff out there at this point. I'd really need to get in front of it and look for myself at this point. It may be time to get a Roland Dealer tech in there to check it out.

 

[2B]

UPDATE,

ordered all new dampers, cables, encoder strips, head, etc... virtually everything one can replace.

though a process of replacing each piece and testing, the issue was found on the print head, there appears to be the smallest of corrosion on the plastic coating the cable that connect to the top of the print head and this looked to have shorted one of the connection points from the cable to the head

have ran the machine 24/7 since repaired and (knock on wood) there has been will be zero issues