Pixma iP8750 starvation problem

[ninj]

I would be grateful for some guidance. My magenta nozzle check is showing starvation (some ink, with U-shaped gap) which persists no matter which cartridges (551) I insert. I have tried 2 sets of refillables and an OEM. The background to this is that I was having magenta nozzle check problems (a couple of horizontal gaps) so I did my usual printhead soaking procedure (in Fairy liquid and deionized water) and for good measure flushed my refillables, including a final flush with Pharmacist's conditioning solution. I'm guessing there is some sort of airlock in the printhead caused by my soaking/drying? Should I try another soaking? (I will, of course, only be doing nozzle checks until this is resolved.)

 

[The Hat]

Can you post a nozzle check so we can have a look at it properly, it’s probably your cartridges that are the problem they are not supplying enough ink to the head, try inserting a tweezers into the cartridge outlet and pulling the sponge down a bit closer to the outlet, that can sometime help?

 

[ninj]

Thanks for replying. The first nozzle check was done this afternoon with a refillable (please forgive the black splodges - scrap paper). The second was done just now with an unused Canon starter OEM cartridge which I just unsealed for this test. As you can see, the magenta has now stopped flowing completely. I have now tried two refillables and two OEMs so I guess it's probably not a cartridge issue?

 

[The Hat]

As I first suspect, it’s a clear case of ink starvation, as to how to resolve the situation easily, that’s a different matter.

The magenta carts, were not suppling enough ink to the print head at first and have now stopped altogether, there is one thing you can try.

Make sure that is plenty of ink in the clear reservoir side of the cart, then get a syringe with a needle attached and poke that through the air hole over the sponge side of the cart.

Use the needle to push down firmly on the sponge, hold the needle at an angle towards the reservoir side and while still pressing down on the needle try and drag the sponge in the opposite direction, then remove the orange clip and try that cart in the print head.

 

[stratman]

then remove the orange clip

Might want to attach the orange clip after removing the cartridge from the print head and before one goes poking around.

 

[The Hat]

@stratman yes of course, it is necessary to go through the normal refilling procedure first to prep a cart for re-use, the above empty cart was shown for illustration purposes only....

 

[ninj]

Many thanks for the clear instructions. I have tried my best to manipulate the sponge as described but, apart from creating a pocket of space around the air vent, I'm not sure that I've managed to achieve much (apart from a bent needle). I guess the idea is to create an air channel along the ink chamber wall? So far no luck with the nozzle check (still blank). I'll try manipulating another cartridge and report back. It would be great if it turns out to be just a cartridge issue, though the fact that even a freshly unsealed Canon cartridge didn't solve the problem make me wonder if the cause could be elsewhere.

Perhaps there is some sort of blockage in the prinhead (maybe introduced by my soaking/drying)? Would it be OK to place the printhead in a little distilled water and use a syringe (with some sort of adapter) on the magenta inlet to draw water up? I guess another thing to check is the rubber gasket not sealing properly, I think I may have a spare somewhere.

Am I right in thinking that if it were a problem with the purge system then every colour would be affected rather than just one, of have I misunderstood how that works?

Thanks for your help.

 

[ninj]

Good news - I got my magenta back! I did two things, so I'm not sure which did the trick: I had a go at manipulated a second refillable as per instructions, but I also cleaned around the gasket with a cotton bud to ensure a good seal. Despite the good nozzle check I will continue with caution in case the problem recurs.

Thanks again! I'm grateful to have learned a new trick for fixing cartridges.

 

[PeterBJ]

Am I right in thinking that if it were a problem with the purge system then every colour would be affected rather than just one, of have I misunderstood how that works?

Yes, the print head is divided into two sections, one section with pigment black for lain paper only and one section for dye inks C, M, Y, K and GY. The purge unit is divided into the same two sections. A problem with the dye section of the purge unit will affect all the dye inks. They might work ok until the cartridges are empty, but will fail when the purge unit should prime the nozzles after a cartridge change.

Thank you for the feed-back.

 

[mikling]

https://youtu.be/tG7JkC1nbQ4

The above video describes another way to fix it.