Canon 525/526 printers repeating clogs

Dear fellow refillers,

I am really stuck with a problem I will try to describe.

I tried to clear the printhead of a Canon MX885 where the cyan and magenta were severily clogged.
Everytime when after bathing the nozzle check was OK, after a few pages the clog was there again.

I suspected the ink (old stock from Prodinks/Sudhaus) and ordered new bottles from OCP, flushed carts and refilled.

With the new inks the result was even worse, I abandoned the printer and took a MX995 with only 900p from my stock.
After replacing the carts with conservation fluid, I placed freshly flushed and refilled cartridges and the nozzle check was perfect.
I tried @The Hat's cartridge test pattern to check the ink flow, but the cyan had some stripes.
After placing the cyan cart into a IX6550 the test was OK, so the cartridge was OK.
(I installed the IX6550 to have a comparision but did not yet did further checks to see if the problem will build up there also).

I did a cleaning, but the cyan continued with stripes.
After a deep cleaning the cyan and magenta were blocked.

By bathing I could revive the magenta but the nozzle check of the cyan was too light.
New bathing revealed that nearly no cyan color was coming out of the head and pushing on a wet kitchen paper showed the cyan flow was limited and there is no cyan print on the paper.

Both the old and new ink is clear.

So it seems to me the ink is reacting inside the printhead into an unresolvable clog.
I bath now in distilled water with a drop of dishwashing fluid and 25% isopropanol.

All help appreciated.

Please post nozzle checks and the cartridge test pattern.

Are there rubber/silicone O-rings that surround the print head's ink inlet port? This is where the cartridge circular ink exit ports connect to the print head.

Have you tried new cartridges? How about trying a different old but known working cartridges?

Are the electrical contacts on the print head and printer clean (not oxidized)? Use either a lint free cloth and isopropyl alcohol or use a soft pencil eraser to clean the contacts if needed.

palombian said:

I bath now in distilled water with a drop of dishwashing fluid and 25% isopropanol.

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Use more liquid dish washing soap to a concentration you would as if washing dishes. I would not add alcohol since it might prevent the enzymes in the liquid dish washing soap from working.

Here the cartridge test and the nozzle check.

I changed cartridges with another printer, both sets worked flawless in this one.

I added more soap (and no alcohol anymore).
Also set the head of the MX885 I abandoned to soak again.
I made a small tool to pump liquid through the ink inlets: it comes out at the nozzle side for all colours.
Will see tomorrow.

Also found an old head (with error) with better O-rings.

palombian said:

Here the cartridge test and the nozzle check.

Click to expand...

1) The cartridge test image shows the typical funnel shaped loss of ink that I associate with ink starvation usually due to a poorly performing cartridge. It could be due to a partial obstruction within the print head that worsens as you print. The solution is to flush and refill the cartridge (make sure the sponge is seated properly) or use a new cartridge. You can also try a known working cartridge.

Maybe there is a combination problem of ink starvation from the cartridge AND defective nozzles. The first thing to do in diagnosing this is to rule out a cartridge issue by trying a new cartridge. Then you can be more certain he print head is the issue.

2) The nozzle check shows a small defect in the Cyan. If this is due to ink starvation from the cartridge then the defect will be variable sized based on length of time since the printer was last used or how long the printing session continues. The idea here is that ink has a difficult time either traversing the sponge and/or sponge uptake of ink from the spongeless side. Once again, try a new cartridge or a freshly flushed one.

If the nozzle check defect is due to burned out nozzles or an electrical malfunction in the print head or logic board then the defect will remain constant sized no matter what fixes you try.

palombian said:

I changed cartridges with another printer, both sets worked flawless in this one.

Click to expand...

Which printer's cartridges worked flawlessly in what printer???


Just curious -- is your purge system working OK?

palombian said:

I added more soap (and no alcohol anymore).

Click to expand...

FYI - The Hat let his print head soak for a week. Patience is key!

Morning results (after soaking the night in water with dishwashing soap):

- the "abandoned" head from the MX885, where I also forced liquid through, had 0 cyan and magenta in the nozzle check as before
- the MX895 (where you've seen the images before, and I did not dare to force liquid since it obviously does not help) was worse than before: see an excerpt of about 10 nozzle checks (only this, no cleaning or whatever)

This is with NEW OCP ink.
Until now it works well in the IX6550, a similar printer.

Seems I invented an auto clogging refilling system .
I am really puzzled and lost all confidence in refilling Canon dye printers and consider to stop losing my time.


There is an offer on a Maxify MB5150, I think I will buy one for my daughter in law.

Still think this is ink starvation due to poor cartridge function. Nozzle burnout does not come back from the dead, function, and then die again, over and over. Poor electrical contact might behave this way, but I would think it would be all or none, not the funnel shaped gradual loss of ink as seen best with Magenta. If there was an electrical failure then it would be constant loss of ink. And, a malfunctioning purge system may cause the loss you are seeing as well as a poorly performing cartridge.

Did you check the purge system as I hinted at before?

Did you try new cartridges? I would try NEW Cyan and Magenta, NOT the same old ones even if they worked in a different printer.

You also did not answer my question about "which cartridges in what printers" I asked in my previous post.

palombian said:

I also forced liquid through

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I do not know what you did but I am not a fan of aggressive measures that might damage the ink channels in the print head. Please describe in detail what your soaking entails.

It seems you've given up even though you have had good but imperfect nozzle checks. I still think a long soak is reasonable to try without the forcing of liquids. And, try NEW cartridges, maybe before you soak the print head again.

I’m looking on and have to agree with @stratman, it seems like a classic case of ink starvation and not the print head at all, you could in fact be making the situation worse by forcing liquid into the print head.

I wouldn’t use the cyan and magenta carts till they were completely purged and refilled again, use cheap compatible aftermarket carts as a good replacement till the issue is resolved...

Since it's Sunday, I agree with @The Hat agreeing with me.

The purge system seems OK, I sprayed some liquid on the pads, it is gone the next time (also, the PBK and Y work as normal and they share the same suction pad).

The printhead was only soaked, no forcing actions.

I placed new OEM carts for C and M, no change, not even after a cleaning cycle.

The same carts who caused the defects above in the MX895 were placed in a IX6550, see cartridge test below (high quality settings).

The cartridges are OEM's, 2 days ago flushed with tap water, demineralised water, pharmacist solution, dried until 11g and refilled up to 20.3g using the German method from new bottles with new syringes.

palombian said:

I placed new OEM carts for C and M, no change, not even after a cleaning cycle.

Click to expand...

If the carts are not to blame, then soak the head in warm water and Fairy liquid soap for a couple of days and make sure to cover the ink inlets...
While the head is soaking print ten test sheets on your IX6550, with the suspect carts installed.