7880 air pressure pump assy failure?

1

Is there anyway to diagnose a 7880 air pressure pump assy failure?

After replacing the dampers, flushing box, and cleaning assembly (capping station, wiper, motor, etc. – the entire assembly) and installing Piezoflush carts in all positions a couple of things: 1.) when I do an init fill the flush is not getting all the way to the head – it actually took 3 - 4 power cleans over an entire day and 2.) I am seeing flush after doing a nozzle on channels 1 - 4 (left ink bay) but not on channels 5 - 8 (right ink bay). I removed the tubes going into the top of the dampers on channels 5 - 8 and confirmed that ink is flowing through them (by moving the locking lever up and down. I was also able to suction ink through these lines using a syringe inserted into the bottom (i.e. where it attaches to the top of the damper) of the L-tube and was able to pull ink through the lines (as I could visibly see where the flush started and the ink ended). After re-assembling everything and doing an initial fill I am not seeing any flush flow through channels 5 - 8 (and can see air in these lines).

I am not getting any service error messages.

Let me know if photos would be helpful.

I am wondering if this could be an air pressure pump failure (or early failure)? Is there anyway to trouble shoot this assembly?

thanks!
Michael

2

Michael did you ever solve this? I’m having a similar issue.
Thanks
Andreas

3

Hi Andreas,

The short answer is no.

Here is a longer answer that may help you.

I did find tiny ink “bits” – not a lot, but noticeable – in the return tubes (from the carts to the air pressure pump). Not so much as to block any of the tubes but enough to note that they should not have been there. If you take off the back of the printer where the air pump is located you can see them there. Additionally if you take off each side panels this gives you access to the rear of the cart assembly housings.

I ended up giving the 7880 to a friend as I was moving. He disassembled the pump and found it full of “gooey” residual ink.

When the printer turns on you should be able to hear the air pump turn on (it is located in the left rear side of the printer – when standing in front). If it is weak or you do not hear it, well… It is one of the few components that is easy to change!

I also read on the Epson large format group a series of messages with a similar problem on a 7880. The author noted that he needed to keep the carts at least half full (2/3 or more was even better) to keep the system pressure pump from being overtaxed. The less full they are, the more air pressure is required. My carts were typically 1/4 - 1/3 full, as I primarily used the 7880 to print negatives.

I had a few carts that were very old. I know the inkjet mall redesigned the carts on subsequent printer family (P6K - P9K) as Epson significantly increased the air pressure. These are “bag in box” style carts and significantly reduce or eliminate any excess air. They are backwards compatible but not sure if they go back as far as the X880 family.

I did have cardboard shims under most of my carts to keep them secure in the ink bays. I did note on a couple of carts where the o-ring was that there was ink where there should not have been any.

As you know, power cleans are not your friend. They should be used sparingly and spaced far apart (meaning in my case no more than two per day separated by at least an hour). A better method of moving ink through system is to use the QTR per channel file to selectively print a “block” of ink using standard “typing” paper.

I suspect that I did not have to change the entire cleaning assembly as the motor was still good. Changing the wiper blade and capping station would have been sufficient. And, of course, changing the dampers (which for me was very delicate as it was easy to over tighten the nuts restricting flow or being too loose and having a leak).

Good luck! Let me know if you have any questions.

(I just picked up an original owner, lightly used P6K and I am going to convert it to piezography as soon as my studio gets completed.)