Could this be the printhead? yellow ink fading and stops

[nippynoo]

Can anyone tell from this test print what the problem is with my MP620?
The yellow ink fades out, and then doesnt print yellow at all, but the yellow cartridge is full of ink.
Is it the printhead? But the yellow starts printing, so presumably isnt blocked?

Here's the test print in much more detail on my uni server
http://itsuite.it.brighton.ac.uk/jjl/tsena/SCN_0012.jpg

Many thanks for any help.

 

[The Hat]

nippynoo

Just looking at your nozzle check I would definitely say you have ink starvation
on your yellow cartridge, so your print head is not to blame.

Which cartridges are you using, OEM or aftermarket and are you refilling them yourself
because this cartridge is just not delivering enough ink to the print head for you.

Can you change the yellow cartridge for another one and then try printing another nozzle check
and come back with some more information to us please..

 

[nippynoo]

Which cartridges are you using, OEM or aftermarket and are you refilling them yourself

I'm using OEM and refilling them using the German method with Image Specialist's inks with squeeze bottles from http://www.octoink.co.uk

Can you change the yellow cartridge for another one and then try printing another nozzle check

I'll try and get another yellow cartridge and try...

I've been thinking some air may have got in last time, as I remember there were some bubbles when I was last refilling, although I cant remember whether that was from the yellow cartridge or another. My bottles were half empty and maybe I didnt hold them vertical enough. Do you think air inside the cartridge would cause the blockage?

 

[The Hat]

You could try refilling the yellow cartridge again but this time when removing the needle continue to squeeze the bottle
as you slowly withdraw it and only stop injecting ink when your needle had reached the outlet hole then remove the needle.

You can do this procedure in about a minute or so then pop the cartridge back into the print head
and try another nozzle, bet it work this time..

 

[nippynoo]

You could try refilling the yellow cartridge again but this time when removing the needle continue to squeeze the bottle
as you slowly withdraw it and only stop injecting ink when your needle had reached the outlet hole then remove the needle.

Thanks TheHat. I tried doing what you said, and the cartridge exit seemed to be flush with ink, and a couple of nozzle checks printed across the full width, so it was looking really promising - but then it dried up again when I did a larger test, and now the nozzle test pattern is doing the same as before... So there's still a block or something? (I'll try a new cartridge as soon as I can get one)

 

[The Hat]

Theres one thing left you could try and that is to tap the bottom of the cartridge on a piece of wood fairly hard
but not hard enough to damaged it and see if that will get the ink flowing again.

The sponge inside your cartridge may not be making good contact with the outlet sponge
and tapping it can cure that problem most times and if that fails well.

The only alternative you have would be to suck out the remaining ink and keep it
then purge clean and dry the cartridge and refill it again..

 

[stratman]

If you tap the cartridge as The Hat suggested to seat a sponge out of position, DO NOT tap on the cylindrical ink exit port on the bottom of the cartridge. If you distort the plastic of this port you may end up with more problems than before.

 

[nippynoo]

I tried tapping the cartridge onto a sheet of rubber but no luck.

I've been thinking - could the German method be the reason the two sponges have separated inside the cartridge, causing the ink starvation? Maybe the needle was too think - and it was blunt ended, not sharp. So required some pressure to get it through, and a bit of wiggling. No wonder the sponge may have lifted. Has this happened to anyone before?

 

[stratman]

Anything is possible. It depends on your technique. If you are getting sponge separation then you aren't doing it right. What instructions are you using - a post or a video?

I use only 18 gauge blunt tipped needles. Never a problem with sponge separation. I will corkscrew the needle to get through the sponge the first time.

 

[PeterBJ]

I wonder if this problem could be caused by the yellow ink, but i think these problems have been solved. Links here: http://www.nifty-stuff.com/forum/viewtopic.php?id=6909 and http://www.nifty-stuff.com/forum/viewtopic.php?id=7022&p=1

I have refilled some CLI-521 Y virgin empty cartridges with Image Specialists ink from Octoinkjet UK. To avoid possible problems I flushed the cartridges very carefully before refill, and have had no problems with them. I don't know if this flushing is necessary, but better safe than sorry.

My refill method is the German method using SqueasyFill bottles and a 2" 21g sharp needle. Just for the purpose of testing I tried using a blunt 22g needle, but even if it is thinner, I found the sharp needle was much better. If you cannot obtain sharp needles, a blunt needle can be sharpened using a fine sharpening stone.