HP Scitex FB550 Light Cyan Not Printing

[rkgraphics]

Hello,
We've had an HP Scitex FB550 Flatbed Printer for about 2 1/2 years. It has recently began printing colors wrong and after a jet health test I can see the Light Cyan is the problem. Half of the bars from the jet health test are missing. I've cleaned the print heads and ran purges with no results.
Just wanted to check if anyone may have some suggestions as to what could be the problem or how to fix it.

Thanks in advance.

 

[flyplainsdrifta]

you can try to empty then fill the printhead thru the service menu. could be air trapped. anything happen that preceded the issue? head strike? run a bag of ink dry?

 

[greysquirrel]

Hello,
We've had an HP Scitex FB550 Flatbed Printer for about 2 1/2 years. It has recently began printing colors wrong and after a jet health test I can see the Light Cyan is the problem. Half of the bars from the jet health test are missing. I've cleaned the print heads and ran purges with no results.
Just wanted to check if anyone may have some suggestions as to what could be the problem or how to fix it.

Thanks in advance.

nozzle print? you can run n 4/c mode. color is quite well...

 

[ellsmako]

sorry dude head is gone bye bye

 

[signman315]

Chances are it's a bad head...they are unpredictable. I've had a single head last years and I've had them last 6 months under the same conditions. We literally never had true head strikes, sometimes a scuff but never a true strike...but the scuffs are sometimes worse. A scuff will drag partially cured ink into adjacent jets which could clogs jets and ruin a head. But anyway the heads have heaters in them to warm the ink to the proper viscosity for jetting, even if your jets and the rest of your head are completely perfect, the heating elements get weaker over time and the ink becomes too thick to jet when it's not warm enough. If your workspace is cold at night or cold in general those heating elements have to work harder to warm the ink. And like any heating element it can go bad in spots or on one side, which would result in the exact problem you're having. Heads are expensive both parts and labor, so I would recommend eliminating all other possibilities first. Such as the ink filters, check your ink filter counts and replace the Lc filter before buying a head. Are both Lc heads having this issue? If it's only one then we can more confidently say it's a bad head, if both are having the issue then we need to look at starvation and the ink delivery system.

 

[Eduardo Massuda]

Chances are it's a bad head...they are unpredictable. I've had a single head last years and I've had them last 6 months under the same conditions. We literally never had true head strikes, sometimes a scuff but never a true strike...but the scuffs are sometimes worse. A scuff will drag partially cured ink into adjacent jets which could clogs jets and ruin a head. But anyway the heads have heaters in them to warm the ink to the proper viscosity for jetting, even if your jets and the rest of your head are completely perfect, the heating elements get weaker over time and the ink becomes too thick to jet when it's not warm enough. If your workspace is cold at night or cold in general those heating elements have to work harder to warm the ink. And like any heating element it can go bad in spots or on one side, which would result in the exact problem you're having. Heads are expensive both parts and labor, so I would recommend eliminating all other possibilities first. Such as the ink filters, check your ink filter counts and replace the Lc filter before buying a head. Are both Lc heads having this issue? If it's only one then we can more confidently say it's a bad head, if both are having the issue then we need to look at starvation and the ink delivery system.

I Had the same problem with this Cyan and Low Cyan heads,
YES CONFIRMED COLD ENVIRONMENT can damaged the heads.....
end up changing 4 heads.... all 2 C, 2 Lc,
Back last year HP had a bad batch of Cyan inks, that maybe end up been one of this inks.
GGS Texas had some, but all fixed as far I know.

but the real problem is actually a top screen on top of the print heads,
So i'm in the missing to flush the head,
mean: there is 2 ports intake inks in the head.... when inks goes in
we have a screen to filter the ink particles size and the heater assembly, followed by the jets.

I got 2 litters CH122A, ($45/EA) to run a line from one sided of the port exiting to other side
and repeat from other side back to other to remove as much possible

and see if I can wash the Crystals out of the screen and see if I can get the same head back in service.
I keep this updated the results.

Also like to post a solution for the ink Vacuum, Since it burns when inks goes to the motor, or clean this vac every 6 months..... Here is the fix.
** just need to Add a longer tube inside the first bucket making sure inks flows down.
avoiding ink fly to the vac port to the Vac pump.
Good luck all....

 

[AMGearhart]

I had this issue with regular cyan. Right in the middle of a print, it started to fade out to nothing. A nozzle check showed ink was flowing, but not at a strong level. It was actually lighter than the light cyan.

I was told that the cyan often settles and clogs the nozzles. It was suggested that I first check if the expiration date was near. Then that I shake my cyan box well, for a minute or two. And to make sure to shake it regularly at least once a week. They to empty the printhead of ink. Then fill. Then repeat at least 3 times in a row. Then to purge two or three times. I don't know if this will help with your situation. But this is what the tech had me do to fix my cyan.

 

[greysquirrel]

Hp has had a run of ink that has issues for these units...before you spend money on it give them a call...or just run the printer in 4/c mode...you will be pleasantly surprised by the output

 

[2M]

Like AMGearhart said, on these machines when the center of the print head is dropping the heads are going bad. Even if you run the health check and they are firing the condition still occurs. The last I knew heads were $1750 per head, and replacing them is not that bad, but calibrating them is not easy. it's a fussy procedure and it comes down to hands on experience. The service manual is not easy to follow and leaves important information out. The first time I replaced heads on one of these it took me about 10 hours to get them calibrated.

If they are not dropping in the center it could be a vacuum or thermoster issue. For me the bad cyan ink only caused color change when I swapped bags. I don't know if that cased jet clogs.

M

 

[Eduardo Massuda]

Like AMGearhart said, on these machines when the center of the print head is dropping the heads are going bad. Even if you run the health check and they are firing the condition still occurs. The last I knew heads were $1750 per head, and replacing them is not that bad, but calibrating them is not easy. it's a fussy procedure and it comes down to hands on experience. The service manual is not easy to follow and leaves important information out. The first time I replaced heads on one of these it took me about 10 hours to get them calibrated.

If they are not dropping in the center it could be a vacuum or thermoster issue. For me the bad cyan ink only caused color change when I swapped bags. I don't know if that cased jet clogs.

M

Learned this week, we have some Cyan and Magenta bad ink batch, I flushed the head with air ( service mode ) and refilled ( ( lot shake all the inks) a new one, after that all problems went away.....
So before anyone decided to change the head, flush the inks on the line and install a new ink bottle. * and claim the ink warranty.

Also learned the heads have heaters, and so in printer area must stay warm.

 

[CORKONBAG]

I have the same issue with white ink, when i make the injectors health recovery it gets better but after a while it clogs again. I never had this problem and this happened after changing the ink box. Anyone with the same problem? The techs say that the problem is the head because no one reported this problem before. I am now about 1 month without printing whites because of this. white ink almost gone in cleanings and losing a lot of money.

 

[balstestrat]

I have the same issue with white ink, when i make the injectors health recovery it gets better but after a while it clogs again. I never had this problem and this happened after changing the ink box. Anyone with the same problem? The techs say that the problem is the head because no one reported this problem before. I am now about 1 month without printing whites because of this. white ink almost gone in cleanings and losing a lot of money. View attachment 149701 View attachment 149702 View attachment 149701 View attachment 149702 View attachment 149703 View attachment 149707 View attachment 149706

I would suspect the head as well.

 

[CORKONBAG]

I would suspect the head as well.

Is there any way to confirm this without replacing the head?

 

[balstestrat]

Is there any way to confirm this without replacing the head?

Well if you have already almost used the new white cartridge that you replaced you should have circulated enough ink to cancel ink issues out.
I don't really see any other option than trying with another white cartridge and emptying and filling that in couple times (there hasn't been any issues with white by HP) and then ultimately replacing the printhead.
Let's see what others say but I hardly doubt there is any other viable solution if you have done everything correctly.

 

[CORKONBAG]

I'm trying to get a new ink box but from a different lot because this one i have now is from the same lot that the one that was replaced because of problems.
I'll keep posted.
Thanks