No, the flow is fine. I would go ahead and use the clips as long as you have them. But see my previous one or two posts. Those four little orange dots? Those are what held the cap on the outlet of the new cartridge until you broke the cap off. Go ahead and trim them. EDIT: I see you had problems due to lack of vacuum. I just tried with a dry cartridge, and it briefly holds a satisfactory vacuum, which will pull back the plunger part way. An ordinary syringe fits the clip and will hold a vacuum. I don't recommend using the InkTec syringes for this, as they have no handle that you can use to pull a vacuum. Make sure you have the vent well sealed.