Hi! new member! I need help and advice. Just bought a 1993 17' nitro dc Rick clunn edition. No manual and pretty much impossible for me to find one the previous own had no answers as well. It just needs some tlc which I'm willing to do. My 1st question is on the opposite side of the boat from the gas intake is some kind of vent I think when I got it it had a plastic cap like a water bottle top and it was ducted covering a round threaded metal knob there is a hose attached to it it's not accessable but I can reach in side the hull and feel it. I thought it might be a air inlet to the gas tank so as you use gas it's displaced by the air but doesn't the gas cap do that? There is obviously a fixture that fits on it but it's like looking for a needle in a hay stack! Help!