Canon Pixma MP620 PG nozzles

[PeterBJ]

Clogged nozzles normally show a random distribution. An electronic failure in the print head and/or logic board will normally show as one or more bands totally missing, one or more bands split horizontally at the middle and one half missing or being lighter than the other half. For pigment black defects a "picket fence" is also often seen:

In my opinion your pigment black shows randomly distributed missing nozzles. This makes me think your printer suffers from clogging and not electronic defects. So I think there is a good chance that a new print head will cure the printer if the old print head cannot be saved.

 

[stratman]

I had tried the paper towel and window cleaner method but made no difference.

Have you tried liquid dish washing soap soaking? You may have nothing to lose and only to gain at this point.

 

[barfl2]

I agree with stratman. There is no need to use a lot of kilobytes to show the unprinted part of the nozzle test sheet. Instead I suggest to use the scanner settings shown in this post. This will hopefully give a better picture of the health of your print head. If you are familiar with service mode operations, the test print from service mode with its extended nozzle check is a good supplement to the regular nozzle check from the printer driver's maintenance tab.

Maybe all is not lost. Your uploaded nozzle check maybe shows only severe clogging and no electronic defects. You might be lucky and have success with cleaning the print head. In stead of pharmacist's cleaning solution you can also use a window cleaner with ammonia.

 

[barfl2]

Thanks for resetting Navigator I have got version Ex.2.0 and unfortunately it appears a lot different to your version. However I have been able to select Un sharp mask off and Descreen On. Image adjust not there. However I have manually made the following adjustments scanning 150dpi from 300dpi Brightness -2 Contrast 4 blur 0 Showthrough 0 new scan follows.

 

[stratman]

Cropped nozzle check allows a better look.

My recommendation remains the same.

 

[barfl2]

Cropped nozzle check allows a better look.

My recommendation remains the same.

 

[barfl2]

Stratman I am trying your Fairy liquid suggestion plus some 5% Ammonia. Rinsed head first in warm water. Then immersed the print head in an aluminium tray on kitchen roll paper folded 4 times. Gently pumped head and down, most action seem to be coming from the Magenta nozzle. For a flow test I use needle covers with the ends cut off, they fit nicely on the small nozzles. Filled these with a syringe and clear water and got steady flow until empty. I do not have any clear plastic 3/8" clear tubing. Improvised by drilling a piece of nylon rod 3/8" it fits OK but is opaque. However the 4ml capacity does not seem to be emptying, or if so very slowly. So I am assuming PG still blocked? I would have thought the much larger tube/nozzle would have flowed faster that the smaller ones. Will leave to soak but perhaps more aggressive tactics are needed. Thanks to PeterBJ tip I have ordered a New head which I hope I can keep in reserve if I can unblock the PG nozzle on this one.

 

[stratman]

You may be the first to add ammonia to dish washing liquid soap for print head clearing. I wonder if that will work in concert or at odds with the enzymes in the soap or some other action of the soap.

i do not perform a flow test as you describe so cannot advise. I would think that a print head that prints most pigment black nozzles is able to pass solution. Maybe there is not enough pressure in the column of fluid to pass the fluid. If you were able to flush the pigment black nozzle with water before soaking then there is patency of some of the channels of the nozzle. Did you flush the print head till little or no ink appears? Is it possible the temperature of the water used to flush the print head "cooked" the pigment ink into a hardened clot? (I have used cold and lukewarm water for flushing and soaking)

Soaking the print head in an inert container, with the solution level above the ink inlets of the print head, with occasional plunging of the print head on the paper towels, changing the soapy solution when it gets a little dirty from ink, and letting it soak for at least a day has worked for me. YMMV since your problems may be different.

Glad to hear you are able to get a genuinely new print head. Whatever happens with your print head will not be in vain. You are at least contributing to the knowledge of the forum. Thank you.

 

[barfl2]

You may be the first to add ammonia to dish washing liquid soap for print head clearing. I wonder if that will work in concert or at odds with the enzymes in the soap or some other action of the soap.

i do not perform a flow test as you describe so cannot advise. I would think that a print head that prints most pigment black nozzles is able to pass solution. Maybe there is not enough pressure in the column of fluid to pass the fluid. If you were able to flush the pigment black nozzle with water before soaking then there is patency of some of the channels of the nozzle. Did you flush the print head till little or no ink appears? Is it possible the temperature of the water used to flush the print head "cooked" the pigment ink into a hardened clot? (I have used cold and lukewarm water for flushing and soaking)

Soaking the print head in an inert container, with the solution level above the ink inlets of the print head, with occasional plunging of the print head on the paper towels, changing the soapy solution when it gets a little dirty from ink, and letting it soak for at least a day has worked for me. YMMV since your problems may be different.

Glad to hear you are able to get a genuinely new print head. Whatever happens with your print head will not be in vain. You are at least contributing to the knowledge of the forum. Thank you.

 

[barfl2]

Thanks for your comments. Spent all day on this Print Head tried Fairy with 5% strength Ammonia, W5 Window Cleaner (The Hats favourite) Isopropanol Tried Push/Pull with a syringe. The paper underneath showed little colour and definitely not the shape of the PG nozzle. Rinsed off with cold water, dried with paper towels finishing off with a hair dryer. Installed Head nozzle check about 25% better. I thought I would try more head cleaning so from control panel I did a head clean followed by a deep clean. In each case the output got worse and worse and now is virtually useless. Could there be a problem with PG ink clogging the cleaning station? One further point the last refill was from a New bottle of ink, should I have shaken it before use?.

I am not sure what to do now, not risking a New Head if there is a problem elsewhere. I did flush with the hot tap had rubber gloves on so not sure how hot it was, but boiler temp.turned down for the Summer so it was not that hot.