Instructions of 700ml Refillable Cartridges for Canon iPF 8000/9000
While covering the cap, please do cover it tightly. Then check whether the two holes is parallel with the cartridge edge, if it is not parallel, please remove the cap, correct the seal position and then cover the cap again. Shake the cartridge to check whether leaking happens, if there is, please replace corresponding part.
While installing, if there is insertion force, please examine whether the two holes is parallel with the cartridge edge just like the below picture.