Plugged heads on 4900 units

Before I discard 3 of my 4 4900s…
I have been running Epson printers for roughly 20 years and for most of them I keep three mid sized professional printers as well as one larger wide format. Currently I have 4-4900 printers of which three are active, two of those have plugs that I can not get rid of. Some are persistent and do not change while some move around. I have run countless cleaning cycles, tried soaking the heads with water and Windex, and run complete flushes with PiezoFlush. After a complete flush I get a clean nozzle test but before I get ink completely charged to the heads I am seeing plugs again. One of the printers is running CC pro inks while two are running Epson. We monitor our humidity and try to keep it below 50%. I have read your post answering the person with a clogged 7900 in which you briefly discuss the issues with head failure on X900 units. I also have read various threads that indicate I may have damaged my heads by too much cleaning. Before I throw these away is there anything I am missing or that I should try, and if not is there any indication that these head problems (you refereed to as delamination) have been corrected in the 5000 unit?

Delam has not been confirmed as fixed in the 5000 unit.

I suggest replacing the ink selector and cleaning unit (at the same time) on one of the 4900s and see if this fixes the problem. My guess (if nozzles are able to come back after a cleaning) is that it’s the top and bottom of the print-head and not the print-head itself.

best,
Walker

Thanks Walker, I will try it on one and see what happens.

Hello Walker, since my last thread I have ordered and replaced the Wiper & Wiper Cleaner as well as the Ink Selector Assembly in one of my 4900s. Immediately all of the old plugs disappeared on a nozzle test, however I did have one small plug show up in PK. After running a couple of cleaning cycles with no change in the nozzle tests I ran a couple of hundred 8.5 x 11 prints. Another test revealed a couple of more plugs, VM, VLM, and LC. Cleaning cycles seem to have no effect. Does this indicate a bad pump, or does it sound more like a head issue. I still have a couple of more 4900 units that I would like to service but hate to throw good money after bad.

This is more of a head issue. Raise your humidity very high, do 1 (normal) cleaning and let sit overnight. Test in morning.

Most likely you have some residual stuff in the intake manifold of the head.

best,
Walker

Thanks, I will work on it.

Hi Walker, in the last 8 days I have increased the humidity substantially. The printer with the new Wiper & Wiper Cleaner and Ink Selector Assembly has cleaned up with the exception of one persistent plug in the LC that I just can’t shake.
I also replaced the Wiper & Wiper Cleaner as well as the Ink Selector Assembly in a second 4900. The issue of roaming plugs PB and to a lesser extent the LB remains. If by chance I am lucky enough to get it clean it is plugged again in a print or two. A cleaning cycle, or letting it set overnight changes the amount and location of the open area on the nozzle test, but does not eliminate the problem. I switched to MB for the heck of it with the same results. Any additional suggestions?