Canon ix4000 purge pads question

[Flatty]

Hello there!

Recently, when I was printing I started to notice that my printer was not printing black propely anymore. There where white lines between the black printed color. I did all those cleaning and deep cleaning and printhad allignments and nothing helped.
Then I stumbled upon this forum and found helpfull posts on how to solve my problem. I took my printhead out and cleaned it with a window cleaning fluid, did the same with the purge pads, until they were properly clean and did not leak any more color.
Then I started to inject the cleaning fluid in the purge pad's holes, which are connected to the tubes that lead the ink to the pads underneath the printer.

Each pad has 2 holes and if you look closely, they are not the same. One hole on each pad works perfectly and the fluid runs nice out from the tubes at the end, but the other hole is a different story. When I inject the fluid there it just backs up and fills the rubber tray, which is holding the pad. I looked at the printer and saw, that there are 4 tubes connected to the purge system, but I only see 2 ends, where the fluid comes out of.
Now my question is, is this normlan and those 2 holes are supposed not to run anywhere, or are those cloged?

I made a photo for better understanding, but can not post is since I am a new member.


Any help appreciated

 

[ghwellsjr]

The two tubes that are closer to the front of the printer go down through the peristaltic pump and out the bottom into the "ink waste tank" which is really a bunch of ink absorber pads that go all across the bottom of the printer.

The other two tubes that are closer to the rear of the printer go to separate valves that allow air to flow into the purge pad cup to prevent the peristaltic pump from sucking ink from the bottom of the print head.

What happens is that the printer normally decides to suck on either the narrow black pigment nozzles or on the dye ink nozzles. I don't think it ever sucks on both at the same time. So if it's time for the black pigment nozzles to be cleaned, it opens the valve on the dye ink side while it runs the peristaltic pump which sucks on both sides but the dye ink side just sucks air instead of ink. Then when it wants to clean the dye ink nozzles it closes the valve on the dye ink side and opens the valve on the pigment ink side.

I think the valves are both normally closed which explains why you cannot inject any fluid into them.

Unfortunately, I, and many others on this forum have been telling people that in order to check the correct operation of your purge pump, you can deposit some Windex or other window cleaning fluid on the pads, see that it remains there for awhile, then close the cover of the printer until the noise stops and then re-open it and the pads should be totally dry. And that's how it worked on all my printers and the printers of my friends that I supplied ink to.

But then I visited a couple friends up North and both of their printers behaved differently. The Windex was not sucked away by closing and re-opening the cover, at least not all on one try. I assumed a clog purge system and so when I got back home, I cleaned up an MP780 that I had bought used but had never used and when I had it apart, I hooked up a loose spare control panel so that I could see the purge pump in action and to my surprise, no Windex was ejected when the "cover" was closed and re-opened. (Actually, just the cover switch since the cover was removed.) The only time Windex was ejected was during the power down process. It didn't happen during power up or just by closing and opening the cover. It, of course, did happen during an actual head cleaning. NOTE: I edited these last two sentences. Sorry for the confusion.

Now I have concluded that the two tubes that go to the valves on all these printers were also clogged which means that whenever the peristaltic pump cycles, it will suck ink out of the print head and not just much more occasionally. This means that the proper test would be to make sure the Windex is not all sucked away just by closing and re-opening the cover but only by doing a legitimate head cleaning.

 

[turbguy]

The two tubes that are closer to the front of the printer go down through the peristaltic pump and out the bottom into the "ink waste tank" which is really a bunch of ink absorber pads that go all across the bottom of the printer.

The other two tubes that are closer to the rear of the printer go to separate valves that allow air to flow into the purge pad cup to prevent the peristaltic pump from sucking ink from the bottom of the print head.

What happens is that the printer normally decides to suck on either the narrow black pigment nozzles or on the dye ink nozzles. I don't think it ever sucks on both at the same time. So if it's time for the black pigment nozzles to be cleaned, it opens the valve on the dye ink side while it runs the peristaltic pump which sucks on both sides but the dye ink side just sucks air instead of ink. Then when it wants to clean the dye ink nozzles it closes the valve on the dye ink side and opens the valve on the pigment ink side.

I think the valves are both normally closed which explains why you cannot inject any fluid into them.

Unfortunately, I, and many others on this forum have been telling people that in order to check the correct operation of your purge pump, you can deposit some Windex or other window cleaning fluid on the pads, see that it remains there for awhile, then close the cover of the printer until the noise stops and then re-open it and the pads should be totally dry. And that's how it worked on all my printers and the printers of my friends that I supplied ink to.

But then I visited a couple friends up North and both of their printers behaved differently. The Windex was not sucked away by closing and re-opening the cover, at least not all on one try. I assumed a clog purge system and so when I got back home, I cleaned up an MP780 that I had bought used but had never used and when I had it apart, I hooked up a loose spare control panel so that I could see the purge pump in action and to my surprise, no Windex was ejected when the "cover" was closed and re-opened. (Actually, just the cover switch since the cover was removed.) The only time Windex was ejected was during the power down process. It didn't happen during power up or during an actual head cleaning.

Now I have concluded that the two tubes that go to the valves on all these printers were also clogged which means that whenever the peristaltic pump cycles, it will suck ink out of the print head and not just much more occasionally. This means that the proper test would be to make sure the Windex is not all sucked away just by closing and re-opening the cover but only by doing a legitimate head cleaning.

Huh?

 

[ghwellsjr]

Huh?

I take it you were confused by my statement that Windex wasn't ejected during an actual head cleaning. It was late at night when I posted that comment. I fixed it. Sorry about the confusion.

Was that the only part that didn't make sense?

 

[turbguy]

Yup!

 

[Grandexp]

But then I visited a couple friends up North and both of their printers behaved differently. The Windex was not sucked away by closing and re-opening the cover, at least not all on one try. I assumed a clog purge system and so when I got back home, I cleaned up an MP780 that I had bought used but had never used and when I had it apart, I hooked up a loose spare control panel so that I could see the purge pump in action and to my surprise, no Windex was ejected when the "cover" was closed and re-opened. (Actually, just the cover switch since the cover was removed.) The only time Windex was ejected was during the power down process. It didn't happen during power up or just by closing and opening the cover. It, of course, did happen during an actual head cleaning. NOTE: I edited these last two sentences. Sorry for the confusion.

I wonder how many have followed your suggestion and made a false diagnosis of their purge units as a result. Nevertheless it is never too late to make a correction. A much precise way to test the purge unit is to fill up a set of cartridges with isopropryl alcohol or simply water. Plug in the cartridges and do a few rounds of deep cleaning. You can then check the level of alcohol or water in the cartridges and tell if the purge unit is working or not. You can't go wrong with this method. The alcohol will vaporize and will not fill up your waste tank.

Now I have concluded that the two tubes that go to the valves on all these printers were also clogged which means that whenever the peristaltic pump cycles, it will suck ink out of the print head and not just much more occasionally. This means that the proper test would be to make sure the Windex is not all sucked away just by closing and re-opening the cover but only by doing a legitimate head cleaning.

Did you find an explanation why the tubes that go into the vales were clogged? If so, as you write, the pump will suck ink out of the print heads. How would the print head develop a clog if ink can be sucked out of the print head? Those two tubes are supposed to be flowing air only. How did they get clogged?

As far as I understand the print head can develop a clog by a faulty purge unit that is unable to suck ink through the print head. If the two tubes that go into the valves are clogged you will only waste a lot of ink but not develop a clog.

 

[ghwellsjr]

But then I visited a couple friends up North and both of their printers behaved differently. The Windex was not sucked away by closing and re-opening the cover, at least not all on one try. I assumed a clog purge system and so when I got back home, I cleaned up an MP780 that I had bought used but had never used and when I had it apart, I hooked up a loose spare control panel so that I could see the purge pump in action and to my surprise, no Windex was ejected when the "cover" was closed and re-opened. (Actually, just the cover switch since the cover was removed.) The only time Windex was ejected was during the power down process. It didn't happen during power up or just by closing and opening the cover. It, of course, did happen during an actual head cleaning. NOTE: I edited these last two sentences. Sorry for the confusion.

I wonder how many have followed your suggestion and made a false diagnosis of their purge units as a result. Nevertheless it is never too late to make a correction. A much precise way to test the purge unit is to fill up a set of cartridges with isopropryl alcohol or simply water. Plug in the cartridges and do a few rounds of deep cleaning. You can then check the level of alcohol or water in the cartridges and tell if the purge unit is working or not. You can't go wrong with this method. The alcohol will vaporize and will not fill up your waste tank.

Yes, there probably have been many that made a false diagnosis and I was among them. If I hadn't believed that false diagnosis I wouldn't have been motivated to clean up another printer and discover that the purge system didn't behave as I expected. I still have plans to take apart another printer and record exactly how the purge system works including how much ink is deposited by a regular cleaning cycle and a deep cleaning cycle and other situations.

My biggest fear is that there may be some printers that I have cleaned up and unclogged the purge tubes and put in new absorber pads and delivered to other friends and yet the tube going to the valve may be clogged. This means that more ink will be going down the purge system into the absorber pads and filling them prematurely. Yuck.

Now I have concluded that the two tubes that go to the valves on all these printers were also clogged which means that whenever the peristaltic pump cycles, it will suck ink out of the print head and not just much more occasionally. This means that the proper test would be to make sure the Windex is not all sucked away just by closing and re-opening the cover but only by doing a legitimate head cleaning.

Did you find an explanation why the tubes that go into the vales were clogged? If so, as you write, the pump will suck ink out of the print heads. How would the print head develop a clog if ink can be sucked out of the print head? Those two tubes are supposed to be flowing air only. How did they get clogged?

As far as I understand the print head can develop a clog by a faulty purge unit that is unable to suck ink through the print head. If the two tubes that go into the valves are clogged you will only waste a lot of ink but not develop a clog.

I believe the tube going to the valve was clogged by the Inkteck pigment black ink that clogged the waste ink pads. I don't know if that tube got clogged before or after the other tube got clogged. My guess is that it happened afterward. Even if the purge system is not working, ink will still be deposited on the purge pads during cleaning or purge cycles because in addition to the purge pump sucking (or attempting to suck) on the bottom of the print head, the nozzles are also firing. If this ink cannot go down the purge tube, it can go down the tube with the valve whenever it is open and it will just sit there until it dries out and clogs the tube. At least that seems like the most reasonable explanation to me.