Pump housing with air in it

[WhoDat?]

I have a pentair challenger.... I thought the strainer basket should be full of water?? It never fills up all the way.... It's like air get trapped in it... I can see water being splashed around through the clear lid... It never loses prime.... But seems to be running loud.... I don't have, or know if I have an air release valve somewhere?? I have a Hayward 24" sand filter.... Im new to this ...
Any info is appreciated!

 

[ROB N]

There should be a little x shaped cap on the top of your filter. If you loosen it when you start the pump and it will release the the air and tighten it back up when the water starts to come out.
Also make sure that the pump basket lid has a good seal with enough lube so that it is not leaking air.

 

[WhoDat?]

Where is the x shaped cap?? I looked for some kind of air release.... I couldn't find it!

 

[ROB N]

Maybe Post a pic of your filter.