4900 head clogs starting to get better but

I have a 4900 that slowly is getting less clogged. It was doing fine with an occasional minor clog and then the VM/C completely clogged. All other heads were fine, but in the process of cleaning, I screwed up all of the heads. The VM/C is now about 80 to 85% good, but there are other heads with varying degrees of clogs. The LLK/Yellow is the only set clog free now (that took some time), one or two spots on LVM/LC, the orange and green has the most missing, most in the orange (about 20%), and the PK/LK has about 5% missing. I have not recently changed to MK to see if it is the same and will try that. I have cleaned the capping station and the wiper with piezio flush, and have cleaned the bottom of the print head. I got a humidifier and have the room at about a constant 30% relative humidity. I have been doing regular paired cleanings, about 1 a day, and letting it sit. It has improved incrementally, but this is over a week with increased humidity (It was probably down about 10% when the problem started).

Most of the clogs are on the top of the page, in the same area, so I wonder if I got a head strike or fibers left behind on a towel wiping early on. It is almost a band across 4 or more colors as the spot that is missing on most heads. I run manual cleaning and turned off auto cleaning.

Do I run a complete head cleaning (all colors) or still try to do the paired colors, and do I do an execute powerful? I have done on execute powerful on orange/green, then let it sit, printed a nozzle check pattern (no change) and then later a regular clean, no change. I also have run a cleaning page, where the individual heads print the colors in one image. That seemed to get me a small improvement.

Would it help to scan a nozzle check pattern printout and upload it?

Is it possible to get just a paired set of cartridges to run such as the green/orange to fill with piezio flush? Do I run the adjustment program to fill only those two cartridges or will it then purge all colors? Not sure on the process.


Bill Bogle, Jr.

Sorry to hear you’re struggling with clogs in your 4900, and for not responding sooner.

After reviewing your order history, I see you bought a 220ml bottle of PiezoFlush, and accessory bag including a cartridge filling funnel, syringe and priming tip- but no cartridges.
What I would do to clean two channels is fill those two position refill carts with PiezoFlush, then do several paired power clean cycles to fill the channels with flush fluid unit pink PiezoFlush prints. I would then carefully clean the capping stations, wiper blade and bottom of the print head. If other channels are having problems, and the missing nozzles are in the top of the nozzle check patterns, then it could very well be gunk or paper towel on the print head, or a good scratch from a head strike on paper. With the 4900, the top of the nozzle check pattern represents the bottom of the print head- the side that faces the front of the printer.
Many people flush all channels at once by installing a set of refill carts filled with PiezoFlush, then preforming an initial fill cycle thru the adjustment program- this is the best way to flush a printer.
Depending on the age and history of this printer, you may need to replace the dampers (ink selector unit), and wiper blade- which should be replaced every few years.

I hope this helps, best regards~ Dana