Water box?

[capt]

Today I took off the clean out port hatch and saw a lot of water in the bottom of this compartment. Is this normal?

 

[Scottintexas]

Is your transom drain plug out?
Is the tongue raised on the trailer to drain water out the back

Can't see how much is in there
Is your boat stored outside?
With cover?
With rain last couple days I wouldn't be surprised to see some trace of water

 

[Daron]

New guy here. Those big metal cylinders are the “water boxes” right? What are the water boxes for? What do they do? I see threads where people insulate them. Education please.