Trying to clean clogged ink supply lines by pulling piezo with syringe from damper end of line

InkjetMall Customer Support
1

I am trying to resurrect an Epson 7800 I was given that sat for years. I tried running a couple of init fills with piezo in a set of cleaning carts and all 4 left side channels printed ok in manual test print, PK was ok with only slight missing spaces, while Y, M and C printed nothing. I pulled the damper assembly and disconnected the supply lines where they attach to the damper nuts at the top/entrance end, put piezo in each of the cleaning carts and then pulled fluid through each line one at a time raising and lowering the ink levers as needed to open and close the line. I was able to clear the M line so I can pull a full syringe (approx. 50ml) of piezo from the carts to the syringe in each of those six lines, but the Y and C will not pull through. I can see air and some ink moving in those clogged lines but cannot see where they might be clogged. I can push some piezo into those lines by putting piezo in the syringe and pushing but only maybe 10ml. I have alternated pushing and pulling piezo for five or ten minutes on each line hoping to loosen up the plug, did that yesterday and then again today but don’t seem to be making any headway of those two lines. Any ideas of how to clear those lines? Should I disassemble the right side cart holder assembly to access the small nipple where the cart attaches and somehow try to pull ink clog or inject piezo into that opening? It looks very small and I am afraid of breaking or messing it up to where it no longer works at all. Can’t find anything on the web regarding trying to replace those two supply lines, seems like I would have to tear down the whole printer to do that and I still don’t know if the head is also clogged, thought I should try to clear the lines first step. Thanks in advance for any advice.

2

In my experience with Piezo flush with my 4800’s, I always found it necessary to follow the advise to allow the flush-time (24-48 hours) to sit, as it needs time to dissolve the ink, as that is what it was designed to do.