Vs-540i Unusual printhead problem

[Adam Edge]

Hi guys,

Having an unusual problem with LC on Vs-540i. Before i describe the issue please note I have been working on my machines to several years and pretty familiar with them. The images will give you a better idea. I've always used OEM link but tried Sam ink. only used on LC and LM. Currently Sam ink in LC. Was it just bad timing or Sam ink damaged the printhead?

Contacted Sam ink, they sent another LC cart and cleaning carts to do a flush.

Steps taken:
Replaced all dampers
Replaced cap station
Replace Choke on LC
Replaced LC ink cart with a new batch from Sam ink
Removed ink line from back of cart to see if there is a ink flow issue
Flushed using 440ml cleaning crts
Several auto and manual clean cycles

After doing all that nothing has changed. Contacted Sam Ink, a second time. they saying it either the print head or the print board.


Image 1:
First test print of the day after sitting overnight

image 2
Pulled ink with syringe, test printed without auto clean, all nozzles fire until i do a print or test print then nozzle missing again

image 3
Pushed ink from top of head then test print without auto clean

image 4
test print looks ok but all grey redish so LC starving

image 5
Nozzle test after above test sheet

image 6
Nozzle test after "Normal Clean"

This is how it is every time no matter how many Auto or Manual clean cycle.

 

[GTSTech_1]

Sorry but none of the pics are working for me......When you remove the connection on top of the printhead, are you getting Lc ink to flow from the connection? If so then perhaps the problem is electrical.

Just my .02

 

[woolly]

far too much cross contamination mostly at the front right edge unfortunately several possibilities.
as you said you have pushed ink from the top internal seals of the head may have failed.
poor pump scavenging, dampers not sealing not uncommon for the old o ring to stay on the head or internal valves failed, can't comment on the ink only ever used oe,
i have now given up on non oe cap tops and not really convinced by the non oe dampers but the price difference is a killer.

 

[Adam Edge]

far too much cross contamination mostly at the front right edge unfortunately several possibilities.
as you said you have pushed ink from the top internal seals of the head may have failed.
poor pump scavenging, dampers not sealing not uncommon for the old o ring to stay on the head or internal valves failed, can't comment on the ink only ever used oe,
i have now given up on non oe cap tops and not really convinced by the non oe dampers but the price difference is a killer.

Hi woolly

no i didnt really push ink, it was always doing that. i only push ink from the cart end as a last attempt ever so slightly with a small syringe, result was same as pulling ink, all nozzles fired.

I dont think there is air leaks bcaz when i choke all colours and only allow ink flow in one line, then i pull ink with syringe the resistance I feel is consistent on all ink lines expect LC. When i choke all except LC and pull ink there isn't air bubbles but instead a lot of back pressure/ resistance.

about the o-ring, first i swapped dampers with another, result was same, then purchased all dampers new and replaced them at the same time and all colours ok except LC, nothing changed by replacing dampers.

 

[Adam Edge]

I even swapped LC ink line with C at cart end but same result. It told me there was no ink flow issue on the lines up until damper/head

 

[woolly]

the fault is across the bottom right corner 4 colours involved even the black is going across which is normally a cap top issue or pump.
is there a re-circulation pump on that channel ? where it would have been a silver and what is the eighth colour

 

[Marcos Shirt]

You have cross contamination. It can be due to bad sealing on the capping (review the 3 axis parking position, specially the vertical sealing -too close is bad due to pad fibers causing capilarity, and too loose brokes the vacuum sealing needed), or the tubes from capping to pump have air leak or clogged with dry ink, or the pump not working well.

 

[Adam Edge]

the fault is across the bottom right corner 4 colours involved even the black is going across which is normally a cap top issue or pump.
is there a re-circulation pump on that channel ? where it would have been a silver and what is the eighth colour

yes its not used, only 7 colour, no white or metallic, re-circulation pump on channel 8 with cleaning fluid. If it was the cap top or pump why only one channel is bad. Dx7 so only 1 head and 1 cap top. Two pumps connected to 1 cap top. I've swapped pump lines numerous times

 

[Adam Edge]

You have cross contamination. It can be due to bad sealing on the capping (review the 3 axis parking position, specially the vertical sealing -too close is bad due to pad fibers causing capilarity, and too loose brokes the vacuum sealing needed), or the tubes from capping to pump have air leak or clogged with dry ink, or the pump not working well.

problem is LC is starving of ink, after pulling ink with syringe and all nozzles fire with ink and i do a small print LC stops flawing into the head so it doesn't put down ink on all nozzles. its either ink flow issue or some low current/electrical problem

 

[C5 Service&Repair]

looks like the manifold in the head is broken. either that or your cross contamination is so bad that your dampers are also contaminated with the wrong color ink.

 

[FrankW]

Check the nozzle plate for damage. Sometimes deep scratches guide to cross contamination.

 

[Marcos Shirt]

problem is LC is starving of ink, after pulling ink with syringe and all nozzles fire with ink and i do a small print LC stops flawing into the head so it doesn't put down ink on all nozzles. its either ink flow issue or some low current/electrical problem

Well, if your only remaining problem is Lc starving (I don't think it is an electrical issue as when you fill the printhead manually, it prints) go and review backwards from the nipple: dampers, tubing, valve, needle and cartridge to see where the ink gets trapped. Also, perhaps you have an air leak in the ink circuit.

 

[Adam Edge]

Update: Internal printhead damage. head replaced. happens just under the nozzle plate, 1 channel leaks into the other.