Hi guys I just bought a 1996 SunBird Neptune 181. I took it out the other day and noticed after I bilged out all the water and pulled the boat out, when I pulled the plug a ton of water came out. I mean alot. When I popped the hatch by the motor where the bilge is it was pretty much dry. This is my first ocean boat but I've never seen this before on any of my past bass boats, there are no holes in the hull or anything weird so what am I looking at? There is a hole on the rear port side with a grommet that is supposed to be there (i dont know what for?) but the water seems to be lower than I am able to see or get to... Any ideas? thanks.