Ernst: You probably think of unresolvable clogs in other printers but the x900 when you say that you have encountered many on other than LLK, don't you? Because between myself and another fellow, we have looked at all the posts mentioning clogs on the Epson LF forum for the x900 since the inception of that series, and same thing here until 1 year back, and pretty much only found LLK ones, with the exception in green previously mentioned.
I also have spent hours talking with AIS, who is a De facto telephone center for folks who experience clogging with inkjet, and Scott could not remember any call for any other color but LLK for x900 printers. I'll concede that these are more or less circumstantial evidences, but the odds that all other colors would have even unconsciously plotted to elude my search are not very good, hence my conclusion so far that there is a problem with LLK. I am posting here so that people can prove me wrong, but remember, only x900 (and that does not include 4900 in this case).
I have also made a test on LLK ink, letting some dry at the air in a ramekin, and amazingly, that stuff does not dry, or more exactly does not harden, it becomes way thicker, like grease on a bicycle chain, but it does not harden. It is hard then to imagine how it could do the kind of thing that Eric showed on the head capping station part of the head.
Alan, about the cleaners I used, they have been tested by AIS as being safe with x900 heads for up to 3.5 weeks, and once again, whatever problems was there, existed before the cleaners went into the head. It just does not make sense that they would clog anything, especially two weeks after being introduced in the head. And if they were causing delamination, they would most likely cause clogs randomly, not around the existing problem as is the pattern. Again, I post here to hear some sensible contradiction.
Eric: the cyan and yellow clogs I saw on the picture of your head would most likely have been cleaned by putting the cleaners (007 and 007+) from AIS for two days or less on the capping station. I hate to break you the news so brutally, but hey, if it was just that, we will all have learned nevertheless and your name will remain in our memory for a few centuries. The gunk going out by reverse pressure, that you write about, seems more worrisome.
I also need to emphasize that the LLK issue that I write about, affects relatively few printers as far as I can see, but enough that there is statistical evidence, whether or not one factors in that a lot of printers from this series are under warranty, extended or otherwise. Only Epson mostly hears about the warranty cases which are nevertheless few enough that even they don't feel that there is the plague out there.
Can't wait to read the rest of the story.
