Canon i850 - need to change print head?

[linefeed]

I have a two year old Canon i850 printer. Every few days some of the colours do not print correctly. Cleaning the print head overcomes the problem but only for a few days. Deep cleaning does not seem to help any more than ordinary cleaning. Black prints OK. I only use Canon carts and the problem has persisted through several change of carts. Do I need to replace the print head? Thanks for any advice.

 

[Manuchau]

You might need a new print head, but there are some solutions posted on the board if you're willing to do some searching...there are specific instructions on how to soak the printhead to dissolve any buildup, and how to blow the nozzles clean with compressed air....keep looking and good luck.

 

[fotofreek]

Manuchau's tip is a good one. Lots of info here about cleaning the print head when the cleaning cycles don't do the job. After a few light cleanings and a deep cleaning you are well advised to move on to remedies that Canon never told you about! You probably have a stubborn enough partial blockage that the cleaning you have done only partially opens the clogs. Just wastes lots of very expensive ink. If you get the printer to print reasonably well for a few days with the cleaning cycles it can probably be restored to proper function with the cleaning techniques you will find here.

 

[Grandad35]

Every few days some of the colours do not print correctly.

Could you define what happens in more detail. Do you see banding, does the overall color change, etc.? Does the nozzle check appear normal? Is there any sign of cross-contamination?

Pull each cart and look for a strange color at each cart's discharge. After the cleaning cycles and when the printer is working properly, print a nozzle check and keep it for reference. When you see the color problem, the colors on the nozzle check will be different if you have an ink cross-contamination problem.

 

[linefeed]

No there's no banding but a change in the colors. Red becomes a rusty color and yellow almost disappears. Can't recall how the nozzle check looks I've had the problem for so long that I just go straight into the cleaning routine. I wouldn't know whether there's cross-contamination, but in what way would the procedure to tackle that differ from a blockage?

 

[Grandad35]

If it's cross-contamination, the usual cause is that the sponge that covers the nozzles when the head is in the parked position is saturated with ink - see the first photo in (http://www.nifty-stuff.com/forum/viewtopic.php?id=161) for a picture of these sponges. Since you don't have any banding, it doesn't sound like conventional "clogging".

The first step is to identify the cause of your problem - let us know what you see when you run the tests that I previously described.

 

[linefeed]

Color problem apparent 7/20. Ran nozzle check yellow appears orange, black appears navy blue, otherwise OK. Did cleaning, repeated nozzle check, all colors & black OK.

Pulled carts, all look OK. Next time problem appears (later today?) I'll examine carts before cleaning.

 

[Grandad35]

Since you didn't say that the nozzle pattern was missing some areas, I'll assume that it was a full pattern. The shift in color indicates an ink contamination problem. Since your problem cleans up with a single cleaning cycle, it appears to be a small contamination that only makes it into the nozzles. It probably does not reach back to the carts, so you may not be able to see it by pulling the carts.

Open the printer cover to get the carriage to its "cart load/unload" position, then pull the power cord. This will allow the carriage to be freely moved and prevent the printer from trying to move the carriage during the next step. Slide the carriage to the far left to get it out of the way and give you access to the right side.

Wear rubber gloves and use several paper towels to carefully blot up the excess ink in the sponges that cover the print head in its parked position (see my previous post). This should eliminate the source of the problem, at least for a while.

When you plug the printer back in and press the "Power On" button, it will run an extended cleaning cycle on its own since it was powered off with the head uncovered.

HTH

 

[linefeed]

I've done as you suggested using several paper towels. I could only see two sponges one about 3/8 inch by 1 inch, the other about 1/2 inch square but I guess they must be the ones. After the switch-on cleaning cycle the print was fine, but after leaving it for an hour it was as before ie the yellow appears as orange. Either I didn't get all the ink out or there's some other problem.

 

[Grandad35]

Because of the color change, it appears to be an ink contamination issue rather than a clog, but I'm running out of ideas on how to fix it. I suppose that an internal leak could have developed inside your print head, but that seems rather unlikely.

Try spraying some glass cleaner (like Windex) into the sponges, then blotting the excess cleaner/ink mixture. Repeat a few times to get the top of the sponges clean, then see if the contamination is still present. If it is coming from the sponges, this should reduce the contamination. It might also be a good idea to pull the print head while the printer is unplugged and use compressed air to blow all of the ink from the print head, just in case there is a buildup of contaminated ink somewhere in the head. Use a cotton swab dipped in rubbing alcohol to clean the electrical contacts on the back of the print head while it is out of the printer.

Does anyone else have any ideas?