New print head - black missing vj1614

[Digiprint]

stuck on this and as usual a friday afternoon. Installed a new printhead and the black is not firing (about 10% nozzle check, others perfect)
changed the damper (2nd) so am guessing problem is with the sub tank. I remember someone saying you can prise open the valve with a screwdriver to allow flow.

am i missing something. i am using mutoh ink bulk system. I do not want to manually draw ink through the printhead at this stage for obvious reasons

thank you to all you helpers out there

 

[Solventinkjet]

Most likely you have a bad cap top or maintenance station. The black is on the edge of the print head which means it is going to be one of the first colors to go when the cap top fails. Even if the maintenance station pulled all the other colors down properly doesn't mean it is working 100%. Unless you are getting a subtank error, it is most likely not a subtank error. There are sensors that tell the printer if it is working properly.

 

[Digiprint]

thank you so much, a new maintenance station it is then, i had a feeling it was suspect, but as 3 colours were 100% didn't give it further thought. Will let you know how it goes

 

[Digiprint]

so, here's the update, fitted a new maintenance station, ink is being pulled through fine, but still no test pattern on black, I can't understand, i am now wondering if it could possibly be anything electronic, fuse etc. the blk damper seems less full than normal, but there is absolutely nothing on test print. the machine is only 3 years use, with less than average use, surely not time to dump it yet

 

[guitarguy69]

Have you tried to pull ink through the bottom of the damper with a seringe yet? could be air lock.

 

[Digiprint]

yes, pulled ink thorough, and expected at least something on nozzle check, but there was nothing. have no doubt that ink is flowing. could it possibly be a damaged printhead. the head is new

 

[guitarguy69]

Can you print a utility mode nozzle check? That should tell you a lot. Also are you missing the nozzles on one bank of black or both? Could be the ribbon cable or board, but let's narrow this down.

 

[Digiprint]

Can you print a utility mode nozzle check? That should tell you a lot. Also are you missing the nozzles on one bank of black or both? Could be the ribbon cable or board, but let's narrow this down.

will try that in the morning, however both banks are not firing, not even a drop. I did put a new ribbon cable when i installed the head. I would have said fuse if there was a fuse for each colour, but i don't think thats the case

 

[Digiprint]

update and more troubleshooting. using a new damper noticed that black ink isn't being drawn through. One thing i was wrong about - the 2 pump tubes don't seem to pull 2 colours each through. i was seeing one tube red so assuming M and Y was being pulled through, and the other black assuming C and K were being pulled through, but this isn't the case, as although the tube was black, the damper was still empty.

anyhow using a syringe at the after damper point on K i am hearing an air leak. It appears to be in the area of the sub tank. It is a pain to see whats going on, but that will be my afternoon job.
Anyone have any idea how to get a good look at the area around the sub tanks, all the plastic covers are off now

cheers

 

[guitarguy69]

I would use some solution on the maintenance station and pull the two small lines off of the drain area and work all the gunk out, then run some cleanings to help clear the lines, with solution in the capping station prior to running the cleanings.

As for the air leak, keep at it and use a stethascope, or something similar and trace that leak down. I have never dealt with that area, except to replace a sub tank solenoid. Let us know how things turn out for you.

 

[Digiprint]

I would use some solution on the maintenance station and pull the two small lines off of the drain area and work all the gunk out, then run some cleanings to help clear the lines, with solution in the capping station prior to running the cleanings.

As for the air leak, keep at it and use a stethascope, or something similar and trace that leak down. I have never dealt with that area, except to replace a sub tank solenoid. Let us know how things turn out for you.

Just had the mutoh techie in. Seems the problem lies with a faulty sensor switch in the sub tank. So, will see if he is right, when he comes with a new sensor

 

[Digiprint]

Just had the mutoh techie in. Seems the problem lies with a faulty sensor switch in the sub tank. So, will see if he is right, when he comes with a new sensor

and the leak, was probably not a leak, but a sucking straw sound caused by pushing ink in and out of the sub tank bag

 

[henryp]

Strange, a faulty sensor on the subtank should result in an error message, I would have thought,

 

[Digiprint]

Strange, a faulty sensor on the subtank should result in an error message, I would have thought,

anyhow that's the opinion of engineer 1. Engineer 2 came this morning, and in all probability the problem is with the printhead/maintenance station as we switched dampers etc.

Just to recap - a new printhead was fitted, no K, a new maintenance station was fitted, still no K

so my question to y'all before i take the printhead out

is there any sort of adjustment, whether menu based or mechanical to align the cap to the head?

as I really think unlikely I was shipped a dud head

cheers

 

[Digiprint]

so another update.

removed (brand new) head

gently pushed solvent through all 8 channels. The 2 K channels are blocked.

so seems to be a screwed printhead, or manifold.

I wonder how helpful the supplier will be?

 

[Jeff South Florida]

Good luck with that. If they do not take care of you, I would separate the manifold and head. Try to push ink through the black channel of the manifold. I find they get clogged. I have cleaned the channels out with a strand of wire and pushed cleaning fluid through. Make sure you wear eye protection because the hose has popped off the manifold and sprayed me. When you reassemble make sure the manifold gasket is in correct.

 

[henryp]

I might have missed it but are you using genuine Mutoh Eco or 3rd party inks?

 

[heyskull]

I am a bit confused with your problem.
If this is a new head and it is blocked on the black channels I would send it back to wherever you purchased it.
It is most certainly dud.
Do not separate the manifold from the head firstly the gasket between them is not a rubber type (at least it wasn't on the one I split apart) it has been placed on in liquid form by a machine and you would not be able to reproduce. Also this would invalidate any warranty still available with the head.
As for the faulty sensor on the subtank this should come up as an error and if the subtank valves are working the error should come up as "subtanklo (then the colour which is showing the error)"
The subtank valves can stick and mine do but their is a menu in maintenance mode to exercise the subtank valves.

On another note you say "a new printhead was fitted, and a new maintenance station was fitted" but you haven't said you replaced the head cable.
If not I would definitely replace the head cable with a genuine mutoh one as a lot of faults with heads are caused by the cable failing due to sovents.

Also I didn't realise mutoh offered a bulk ink system for this machine?!

SC
[h=2][/h]

 

[Digiprint]

not surprised of the confusion, there has been a lot of fault finding going on

anyhow it is definitely the printhead, we've put the old one back, and all is fine albeit missing nozzles, which is the reason, i wanted to put a new one in the first place.

I guess the reason it took long to find the problem is that no-one expected a brand new mutoh print head to be faulty, but most definitely the black channels are 100% blocked

A new print head cable was fitted at the same time.

The bulk system was offered at time of purchase through local supplier, and i am using 1L mutoh inks.

Totally agree, about not removing manifold, that is for a last resort deciding between dustbin, or have a go.

I am in touch with the supplier, and I am sure they are reasonable

cheers

I am a bit confused with your problem.
If this is a new head and it is blocked on the black channels I would send it back to wherever you purchased it.
It is most certainly dud.
Do not separate the manifold from the head firstly the gasket between them is not a rubber type (at least it wasn't on the one I split apart) it has been placed on in liquid form by a machine and you would not be able to reproduce. Also this would invalidate any warranty still available with the head.
As for the faulty sensor on the subtank this should come up as an error and if the subtank valves are working the error should come up as "subtanklo (then the colour which is showing the error)"
The subtank valves can stick and mine do but their is a menu in maintenance mode to exercise the subtank valves.

On another note you say "a new printhead was fitted, and a new maintenance station was fitted" but you haven't said you replaced the head cable.
If not I would definitely replace the head cable with a genuine mutoh one as a lot of faults with heads are caused by the cable failing due to sovents.

Also I didn't realise mutoh offered a bulk ink system for this machine?!

SC

 

[Jeff South Florida]

I clearly said " If they do not take care of you, I would separate the manifold and head." With this being said, I am confused about something you just said. You said you have a Mutoh 1614. The Mutoh high capacity system will not work in there without major modifications. I question whether this is a Mutoh system.

On to the real problem. If it is a VJ-1614 you can syringe ink in to the damper directly from the bottom of the damper. I would then let it sit and see if air gets in the line. If so it is obviously pre-damper and not a head issue. Now this could have caused a head issue and allowed ink to dry in it. On the same note, if you can syringe the ink it is probably from the damper down. After it sits and no air gets in line, put the dampers back on the tubes leading to the manifold. I would then syringe it again. See if ink goes through those tubes. This should answer all of your questions.