K head stopped printing

[Airborneltp]

So my black print head just stopped working. It was working fine then would not show up on a test print. It slowly died out. I thought it was a clogged issue so I cleaned it up real good and checked the capping station and everything…. Still nothing….
Then I went behind the machine and pulled ink through and had no issues…. Did a test print and it worked for acouple test prints then died…. I figured I was losing suction and replaced both dampners and once again pulled through the back of the machine….
I get a lot of ink coming though and it has no bad test print so the heads are not clogged… but its not holding ink during print… it just wont print at all…
Now when I pull through the back of the machine I still get the same ink coming through but now it will not do a good test print….
Im wondering if it’s the capping ring and if that needs replaced…. The pumps work fine as they hold solution during the wash cycle or soaking cycle…. So I don’t know what to do.

 

[Airborneltp]

really.... 35 views and not a single suggestion?

 

[DougWestwood]

air bubbles?

Hey There,

Sounds like air bubbles in the line. Seems you have done all the normal fixes for that.
Maybe there's a faulty damper? Loose hose connection? Do you see any leaks?
Leaky air filter?

Would be good to know what make/model/size printer you have.
Mimaki, I'm guessing.

- Doug
Vancouver

 

[DougWestwood]

check for cracks in plastic parts

Also,take a close look for cracks in plastic parts. Seams, corners, undersides all can hide cracks which will let in air. I would say look at the TOP of things, since a crack/leak on the BOTTOM would cause visible ink drips/puddles. Cracks on the top of a plastic part would let in air.

Good Luck!
- Doug Vancouver

 

[Airborneltp]

Yea my bad... i have mimaki jv3-160sp i replaced all dampners but im begining to think i cracked a manifold... but it was doing this before i did anything.... im at a loss right now....

 

[Airborneltp]

just pulled dampners to check manifolds, the manifold is intake, no breaks anywhere, and i have new dampners..... my pumps work because of nozzle wash test and im lost... i checked all cables into the slider board so... i dunno.... im boout to pull like 40cc's of black ink through the pumps in a minute if i cant figure something else out

 

[MikePro]

could just be a bad connection between your capping station and the printhead, essentially not properly refreshing the siphon-effect of your ink supply to the printhead.

try running a fillupink through the black printhead. if i'm right, you should be hearing a hissing noise at the printhead and not seeing ink drain through the waste line.
quick-fix, for me, was to slightly shift-upwards the black cap on the capping station. the printhead will snug the fit when it parks back on top.

 

[DougWestwood]

ink filter?

Hey,

Where is the ink filter on this model? If you've checked the dampers
and the air filters, maybe a leak near the ink filters?

Also, is there a rubber gasket around the capping station?
I had a red head drop out when suction was lost at the capping station.

Check for a slight band of dried ink around the edge of the gasket.
The one causing my problem was thinner than a small rubber band.
Very slight. Tech pulled it out in one long piece.

- Doug

 

[Airborneltp]

Ok so i just did somthing strange and risky.... I looked EVERYWHERE!!!! i mean inside and out and when i was examining my capping station i noticed splatter from CYAN dampner replacement from around the time it stopped working.... there was splatter on the ENCODER STRIP behind the head carriage.... so i took a microfiber cleaning swap (or the one recommneded... not cotton) and began dry rubbing it lightly on the strip... ALOT of it came off. So i dampened the swab and cleaned more. Waiting till it was completley dry and turned the machine on. And wouldnt you know it? it worked the first test print....

now i dont know if that has anything to do with it, but it was fixed right after i cleaned the encoder strip. So.... there ya go

 

[Airborneltp]

hey thanks Doug for following up with me. I did notice alot of gunk and gave all my rubber seals a real good and deep clean, their practically new, and alot i noticed a small change it never was 100%.

 

[DougWestwood]

Awesome!

Great! Glad you found the problem.
Even happier you shared the results.

Rock On!
- Doug
Vancouver