Canon BCI-6 yellow ink turns black

[Mosskeeto]

I have a Canon i950 printer that I use on and off for photo printing only. For a long time I only used Canon inks and this problem started gradually and is now become a major issue. In the last year I've co-mingled only one third party ink brand in my printer and that one is G&G. The Yellow ink cartridge will change to a blackish color in as little as 2 weeks time, as occurred most recently. The Canon service rep said I should take it in for service and on a different website the responses from people who had the same problem seem to indicate a hairline crack in the printhead. I see that someone here mentioned the problem last year and I was wondering if the aircleaning method has ever fixed this issue.
Also: I've done all the usual cleanings, nozzle checks, etc. and I notice that sometimes there appears a missing spot of color in the nozzle check pattern, i.e.- the grid will not be absolutely perfect.

 

[Grandad35]

http://www.nifty-stuff.com/forum/viewtopic.php?id=347

 

[Mosskeeto]

Yesterday I decided to try the more advanced cleaning method using compressed air. After quite a bit of ink was expelled, and doing the usual re-tests and regular cleaning, I used paper towels to clear some of the ink in the sponge well. I noticed that the ceramic print head rest was dark and any yellow ink was undetectable, so I also cleaned that area with a paper towel. I changed to a fresh Yellow BCI-6 and printed some 25 5x7 photos plus some 8x10s. Overall the quality was OK but they were too reddish although they got a little better further into the run.
This morning I thought I'd inspect the inks and no surprise- the yellow ink was beginning to turn black on the sponge side and the ceramic rest was very dark with blue, red visible but no yellow. Does this example eliminate everything but a printhead problem?

 

[Tin Ho]

Problem like this is often caused by a faulty ink cartridge. Swap the black with another one. This may be a quick fix.

 

[RC]

To Mooskeeto:

I have encountered the same problem and the cause was e defective cartridge, in your case either the yellow or the black, more likely the black.

Another cause may be the rubber seals in the printhead. With time they may get slightly compressed, therefore not pressing has hard on the cartridge and not creating a good vacuum seal. I have found that this can be corrected by simply summering the seals in hot water for about 5 minutes. When you take them out of the water let them get cool before you put them back in the printhead.

What this does is, it allows the seals to regain some of its original shape, therefore pressing a little harder on the cartridge.

Hope this will be of some help.

By the way, this can happen very easily if you use SkyHorse cartridges.

Robert

 

[Mosskeeto]

I don't think my problem is related to a leaking ink cartridge as I have replaced Black ink tanks before (that were still 1/2 full) because I thought the color was off- becoming tinged with violet. I only used OEM inks for the first 2 years and just starting using G&G recently; the problem began while I still used Canon inks exclusively. The ink tanks in there now are co-mingled but show no outside evidence of leaking. I sounds as if some of you had success without replacing the printhead. Did your ceramic head stop look as dark as mine?