Why my pump isn't pumping?

I have dual d5 pumps that runs into issues if the pumps aren't fully saturated with water (ie primed). I usually disconnect a tube down stream from the pumps and use some suction to pull water though the pumps. Once this is done I reconnect and boot up. If your pump is not primed no water will flow. So my question is are you certain your pump is primed?
 


primed? Pump worked fine before...Now I have two inlets-one from the res and the other one comes from GPU and one outlet connected to the pump top that goes to CPU block....Water comes to the pump,and pushes the water trough outlet port but it seems like there isn't enough pressure because pump makes that squeaking sound like it doesn't get enough of H2O...Tilting the case didn't help at all...
 
I get it worked before but i am still seeing air in both tubes leaving the pump. Not sure how that happened but that is what I see in your pic. This can cause the pump to not pump. Now if you shaked the case that would likely get water into the pump, something I have done myself in the past if my pump was close but not quite primed. Ideally using suction to pull fluid through the pump is best though. Try this now. If it fixes things you know you had air in your pump. If it doesn't fix things you probably need a new pump.
 
My pump is working,but my tube layout is bad....I should have used top inlet for reservoir because I used the same outlet,so the pressure would be higher...Not like this,side inlet and top outlet and inlet,ofc it cant push the air out....Yes,your method is good,but unfortunately I don't have eligible place in my loop for that,,,,with what do you suck the air out?