Have a Canon 9000 Mark II I use for test prints and general office printing. I use refills on it with OCP ink.
Noticed some streakiness going on and thought it was a head issue. I have another head and all was well for a while, then the streaks came back so I began suspecting the refills.
On one site (Precision Inks), the guy mentions the small air maze vent under the top front labels of the Canon ink carts. I've noticed it leaking at times when I refill. He said when it plugs you get messy output due to the plugged vent. Sounds like the ink cannot drain down onto the printhead if it doesn't allow for air to enter and for the ink to drain out the port at the bottom.
Was wondering if there is a plug of ink in that air vent and if it might be an issue? So how can one unplug it?
I thought about taking a small hot needle and burning a hole in the top of the cart to vent it, and cover it with tape to seal it for storage until used later. Ink will probably run out like it does before I can seal the tank back up, but it isn't on the head then either.
Any thoughts on adding an extra vent hole?
SG
